Neural Mechanisms of Stress Effects Across Hippocampal Encoding and Prediction
Phase: NA
Conditions: Stress, Learning, Spatial
Sponsor: Yale University

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STUDY PROTOCOL
Social Behavioral Template
   
Influence of stress on learning and memory
 Protocol Number
Protocol Number
 
Protocol Version
Version Date: 11/21/23
 Version # 1
Clinical Trials Registration Number (if applicable)
Confidentiality Statement:
We, the researchers on the project Influence of stress on learning and memory, will have 
access to data which contains confidential information that respondents generally perceive 
as personal and private.  We understand that access to this confidential information and 
data carries with it responsibility to guard against unauthorized use and to abide by the data 
security plan.  To treat information as confidential means to not divulge it or make it 
accessible to anyone who is not a project member.  Such a disclosure would violate the 
confidentiality promised to participants and would violate University ethics policies.
We agree to fulfill my responsibilities on this project in accordance with the following
1.
We agree to not permit non-project personnel access to the data, either 
electronically, in hard copy or orally.
2.
We agree to not attempt to identify individuals except in those cases where it is 
necessary in accordance with my role on the research project.
3.
We agree that in the event we inadvertently uncover the identity of an individual, we 
will maintain the highest level of confidentiality of this information, make no use of the 
knowledge and inform the study’s Principal Investigator.
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Synopsis
Purpose
The purpose of this study is to understand how stress impacts different forms of learning 
and memory. Stress is a significant public health issue, and by understanding stress 
effects on different types of learning, the research may help to inform optimized 
treatment of stress-related psychopathology. 
Objectives
The objective of this study is to leverage novel behavioral and neuroimaging assays to 
determine how stress modulates distinct hippocampal learning processes in humans. 
Using a between-subjects design, we will investigate whether exposure to a mild 
laboratory stressor changes the formation of different types of memories; specifically, 
storing individual experiences (episodic encoding) and learning environmental regularities 
(statistical learning). Our central hypothesis is that stress will modulate hippocampal 
responses and connectivity to enhance statistical learning while impairing episodic 
encoding. The following specific aims will be addressed:
Aim 1. Characterize how acute stress affects the relative expression of statistical learning 
and episodic encoding. 
Aim 2. Identify the neural mechanisms by which stress influences statistical learning and 
episodic encoding.
As a secondary objective, we will determine whether individual variability in the magnitude 
of the stress response influences the effects of stress on hippocampal learning.
Study Population
Participants in this study will be healthy individuals aged 18-45. We aim to study this 
healthy cohort in order to understand the baseline relationship between stress and 
memory in neurotypical individuals. 
Number of Participants
Approximately five-hundred participants will be enrolled in the study. We plan to run 
between two and four behavioral studies (N = 46-138 each, depending on the exact 
parameters of the study) and one fMRI study (N = 100). These numbers are based on 
power analyses from similar behavioral and fMRI studies (Sherman & Turk-Browne, 
2020). 
Study Design
In this two-day study, participants will be exposed to a series of displays (e.g., scene 
images) and subsequently be tested on their memory for these displays. Some 
participants may undergo a stress manipulation, known as the cold pressor test 
(described below). Some participants may also undergo fMRI, so we can analyze how 
brain response patterns associated with learning and memory change as a function of 
stress exposure. Please see sections 4 and 6 for more detailed information about the 
study design and methodology. 
Study Duration
We expect the total duration of the study to last 2-3 years. Each participant will participate 
in two sessions. The first session will take 1-2 hours and the second session will take 0.5-
1 hour.
Outcome Variables
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The primary outcome variables will be performance on the behavioral learning and 
memory tasks. Additionally, we will examine cortisol and alpha-amylase responses to 
stress. In the fMRI study, we will additionally examine neural correlates of learning and 
memory.
Locations/Facilities
Some behavioral studies will take place in Sheffield-Sterling-Strathcona (SSS) Hall (1 
Prospect Street) or 100 College Street and some will be run online (on mTurk or Prolific).
The fMRI studies will take place in the FAS Brain Imaging Center in Dunham Lab (10 
Hillhouse Avenue) or BrainWorks at 100 College Street.
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Abbreviations
Abbreviation 
Explanation
fMRI
Functional Magnetic Resonance Imaging: a 
non-invasive brain imaging method
CPT
Cold Pressor Task: a validated and safe 
method for inducing stress in a laboratory 
setting
BIC
FAS Brain Imaging Center
BOLD
Blood-oxygenation-level-dependent signal: 
the outcome measure of fMRI data
TSP
Trisynaptic pathway: the hippocampal 
pathway hypothesized to be involved in 
episodic memory
MSP
Monosynaptic pathway: the hippocampal 
pathway hypothesized to be involved in 
statistical learning
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Glossary of Terms
Glossary
Explanation
Hippocampus
A brain region involved in multiple kinds 
of learning and memory, which we expect 
to be impacted by stress
Episodic Memory
A kind of memory which holds rich and 
detailed information for specific events
Statistical Learning
A kind of memory which is more 
generalized and abstract, allowing for 
prediction of future events
Acute stress
A form of stress that is short-term (i.e., as 
induced in our study); as opposed to 
chronic stress
Alpha-amylase/adrenergic
The adrenergic system is activated upon 
exposure to acute stress. It can be measured 
through alpha-amylase concentrations in 
saliva.
Cortisol/glucocorticoid
The release of glucocorticoids (cortisol in 
humans) is the end product of the 
hypothalamic-pituitary-adrenal axis 
response to stress. It can be measured 
through cortisol concentrations in saliva.
Milgram
Yale’s HIPAA-aligned computer cluster, 
managed by the Yale Center for Research 
Computing
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Table of Contents
Preface........................................................................................................................................2
Synopsis .....................................................................................................................................3
Purpose ...................................................................................................................................3
Objectives...............................................................................................................................3
Study Population ....................................................................................................................3
Number of Participants...........................................................................................................3
Study Design ..........................................................................................................................3
Study Duration........................................................................................................................3
Outcome Variables.................................................................................................................3
Locations/Facilities.................................................................................................................3
Abbreviations.............................................................................................................................4
Glossary of Terms......................................................................................................................5
Protocol Revision History..........................................................................................................9
1
Background.......................................................................................................................10
1.1
Background................................................................................................................10
1.2
Prior Experience (if applicable) ................................................................................10
2
Rationale/Significance......................................................................................................11
2.1
Rationale and Study Significance..............................................................................11
2.2
Risks ..........................................................................................................................11
2.3
Anticipated Benefits..................................................................................................11
3
Study Purpose and Objectives ..........................................................................................12
3.1
Purpose ......................................................................................................................12
3.2
Hypothesis.................................................................................................................12
3.3
Objectives..................................................................................................................12
4
Study Design.....................................................................................................................13
4.1
Study Duration...........................................................................................................15
4.2
Outcome Variables/Endpoints...................................................................................15
4.2.1
Primary Outcome Variables/Endpoints..............................................................15
4.2.2
Secondary and Exploratory Outcome Variables/Endpoints (if applicable) .......15
5
Study Participants .............................................................................................................16
5.1
Study Population .......................................................................................................16
5.2
Number of Participants..............................................................................................16
5.3
Eligibility Criteria......................................................................................................16
5.4
Recruitment Procedures ............................................................................................17
5.5
Consent/Assent Procedures/HIPAA Authorization...................................................17
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6
Study Methods/Procedures ...............................................................................................20
6.1
Study Procedures.......................................................................................................20
6.1.1
Data Collection...................................................................................................21
6.2
Method of Assignment/Randomization (if applicable) .............................................21
6.3
Adverse Events Definition and Reporting.................................................................21
6.4
Reaction Management...............................................................................................21
6.5
Withdrawal Procedures .............................................................................................22
6.6
Locations/Facilities....................................................................................................22
7
Statistical Design ..............................................................................................................23
7.1
Sample Size Considerations ......................................................................................23
7.2
Planned Analyses.......................................................................................................23
7.2.1
Secondary Objective Analyses (if applicable) ...................................................23
7.2.2
Analysis of Subject Characteristics (if applicable) ............................................23
7.2.3
Interim Analysis (if applicable) .........................................................................23
7.3
Data Relevance..........................................................................................................24
7.4
Data Coding...............................................................................................................24
7.5
Data Analysis Tools ..................................................................................................24
7.6
Data Monitoring ........................................................................................................24
7.7
Handling of Missing Data .........................................................................................24
8
Data/Specimen Handling and Record Keeping ................................................................25
8.1
Subject Data Confidentiality .....................................................................................25
8.2
Data Quality Assurance.............................................................................................26
8.3
Data or Specimen Storage/Security...........................................................................26
8.4
Study Records............................................................................................................26
8.5
Access to Source........................................................................................................26
8.6
Retention of Records.................................................................................................26
8.7
Data and Safety Monitoring Plan ..............................................................................27
9
Study Considerations........................................................................................................28
9.1
Institutional Review Board (IRB) Review ................................................................28
9.2
Research Personnel Training.....................................................................................28
9.3
Study Monitoring.......................................................................................................28
9.4
Unanticipated Problems and Protocol Deviations.....................................................29
9.5
Study Discontinuation ...............................................................................................30
9.6
Study Completion......................................................................................................30
9.7
Conflict of Interest Management Plan.......................................................................30
9.8
Funding Source..........................................................................................................31
9.9
Publication Plan.........................................................................................................31
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10
Appendices....................................................................................................................32
11
List of Tables.................................................................................................................33
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Protocol Revision History
Version 
Date
Summary of Substantial Changes
8/25/2021
Adding online testing; video recording during CPT
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1 Background
1.1
Background
Stress is a serious and escalating public health issue, with average stress levels in 2020 
significantly increasing in the US for the first time since national assessments began in 2007 
(APA, 2020). High stress levels are linked to increased risk of adverse physical (Richardson 
et al., 2012; Booth et al., 2015; Gianaros et al., 2015) and mental (Sinha, 2001; Gruber et 
al., 2020; Vinkers et al., 2014) health outcomes spanning diagnostic categories. Although 
the influence of stress on the hippocampus, an important hub for learning, has been posited 
to play a crucial role in mental health outcomes (Goldfarb & Sinha, 2018; Lee et al., 2002), 
this target mechanism remains poorly understood. 
Advances in nonhuman animal research have revealed distinct stress effects across 
hippocampal subregions (Gould et al., 1998; Pavlides et al., 1993; Sapolsky et al., 1990; 
Chen et al., 2010; Ghosh et al., 2013; Gerges et al., 2001; McLaughlin et al., 2005; Pu et al., 
2007). Intriguingly, these discrepancies map onto the trisynaptic (TSP) and monosynaptic 
(MSP) pathways of hippocampal transmission, with stress impairing the subregions involved 
in the TSP and sparing the subregions involved in the MSP. This suggests the novel 
hypothesis that stress will differentially impact learning processes supported by these 
pathways, impairing TSP-dependent while enhancing MSP-dependent functions. Recent 
work shows that these pathways make distinct contributions to different forms of learning, 
providing a unique opportunity to test stress effects across hippocampal pathways in 
humans. 
Specifically, a neural network model of the hippocampus (Schapiro et al., 2017) 
demonstrates that these two different pathways are associated with two fundamentally 
different kinds of learning. The TSP may support episodic encoding, a kind of memory which 
allows for the memory of specific experiences (e.g., your most recent birthday). The MSP, on 
the other hand, may support statistical learning, a kind of memory which allows for the 
abstraction or generalization across many experiences (e.g., what a birthday tends to be 
like). Recent empirical work from the Turk-Browne lab shows that forming predictions about 
an upcoming experience (via statistical learning) impairs episodic encoding of the current 
experience (Sherman & Turk-Browne, 2020), suggesting that stress may both influence 
these learning systems separately and drive competition between them. Thus, in this study, 
we aim to understand how stress differentially influences episodic memory and statistical 
learning, and whether this is reflected in how stress influences hippocampal pathway 
function, as measured with fMRI. 
1.2
Prior Experience (if applicable) 
Please see background section about for relevant prior work from our labs in these domains. 
In addition, we have extensive experience administering the laboratory stress induction 
described here (e.g., Goldfarb, Mendelevich & Phelps 2017; Goldfarb et al 2017; Goldfarb et 
al 2019).
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2 Rationale/Significance
2.1
Rationale and Study Significance 
Stress is a serious and escalating public health issue, with average stress levels in 2020 
significantly increasing in the US for the first time since national assessments began in 2007 
(APA, 2020). High stress levels are linked to increased risk of adverse physical and mental 
health outcomes spanning diagnostic categories. Although the influence of stress on the 
hippocampus, an important hub for learning, has been posited to play a crucial role in mental 
health outcomes, this target mechanism remains poorly understood. In particular, it is 
unclear how stress affects learning computations supported by different hippocampal 
pathways. This study proposes to develop and validate behavioral and neuroimaging 
techniques to test novel hypotheses disentangling stress effects across hippocampal 
learning processes in humans. 
2.2
Risks
Cold pressor test. The Cold Pressor Test (CPT) procedure has been used successfully with 
both children and adults without reported adverse effects (Von Baeyer et al., 2005; 
Kowalcyzk et al., 2006; Siegrist et al., 2006; Silverthorn and Michael, 2013; Goldfarb et al 
2017a,b; Goldfarb et al 2019).  Participants may experience some discomfort during this task 
(submerging their hand in a bucket of water). Participants will be able to withdraw from the 
experiment at any time without loss of compensation (prorated to the length of participation), 
and will have time to rest after completion of the CPT. Participants will be given a paper 
towel to wipe their arm after the stressor is over, and they will be given time to rest.
MRI environment. There are no known risks in the use of MRI per se and 3-T scanners are 
FDA-approved for all ages. However, there are some potential areas of concern. The first is 
the possibility of the static magnetic field attracting ferromagnetic objects toward the bore, 
which includes internal devices. The second is the loud noise made by the gradients during 
imaging. Finally, participants may feel dizzy, get an upset stomach, have a metallic taste, or 
feel tingling sensations or muscle twitches. These concerns exist for all MRI studies and 
routine exams and are not increased by the proposed research.
All studies will follow guidelines set by the FDA with regard to specific absorption ratio, limits 
on gradient slew rate (dB/dt), and acoustic noise. We will use a 3-T scanner that conforms to 
FDA safety guidelines. Such scanners are available for research and clinical studies at most 
major medical centers and research universities and have been used for a number of years. 
Safety procedures will be rigorously enforced. Members of the research team receive 
intensive safety training and periodic re-training. 
Subjects will be screened for contraindications to scanning, including moderate or severe 
claustrophobia, and a history or possible history of intra-ocular, intracranial, intrathorax, or 
intra-abdominal metal or cardiac pacemakers. Although there are no known risks to a fetus, 
if the participant is female and there is any chance they could be pregnant, the safety 
concerns will be explained to the participant and they will be excluded.
Participants and researchers are instructed to remove all metal objects before entering the 
scanner room, which is verified with the walkthrough and wand-based metal detectors. The 
risk of noise exposure is minimized by hearing protection, bringing the sound pressure level 
below FDA limits. Feeling dizzy, getting an upset stomach, having a metallic taste, or feeling 
tingling sensations or muscle twitches are known potential effects of MRI and usually go 
away quickly. Researchers will alert participants to this possibility and request that they 
inform the researchers if they are experiencing any of these effects. 
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During scanning sessions, participants will be made as comfortable as possible, with the 
option of a pad to rest their legs on or a sheet to cover them. The researcher will be in 
communication with the participant between runs throughout the scanning session. 
Participants will be instructed to signal to the researcher in the scanner room if they need to 
stop at any time, by pressing the squeeze ball or button. 
We are always willing to adapt our scanning protocol to any changes in the laws or 
guidelines set forth by the BIC, BrainWorks, the Yale New Haven Hospital, Yale University, 
or the FDA. Furthermore, we make all scanner-related risks clear to the participant during 
the screening and consent so that the participant can make a well informed decision about 
participating.
Incidental findings. This study is not in any way a healthcare examination of the brain, the 
images we collect are not designed to find abnormalities, and the researchers are not 
qualified to interpret the images medically. However, a worrisome finding may be seen 
incidentally during the course of the study. If a worrisome finding is seen incidentally on a 
participant’s scan during the course of the study, the principal investigator will contact the 
participant, inform them of the finding, and recommend that they seek medical advice as a 
precautionary measure. The decision for additional examination or treatment is up to the 
participant and their physician.
Privacy. A loss of confidentiality is a risk of any research study. MRI data can contain data of 
medical importance and also identifying information. This could affect the confidentiality of 
the participants.
All participant data will be anonymized at the earliest convenience and given a de-identified 
participant ID. Only the PIs and members of the research team will be able to link the 
participant ID with identifiable details of the participant. This link will be stored in password-
protected files on encrypted and password-protected computers, housed in locked 
laboratory space. We will plan to share anonymized data with collaborators and post them in 
data repositories required by our grant funding and by scientific journals. MRI data will be 
directly transferred from the scanner to HIPAA-aligned Yale servers. Other data on 
computers in the control room (e.g., behavioral responses, eye-tracking images) will either 
also be transferred securely over the network or get transferred manually onto an encrypted, 
passcode protected flash drive.
2.3
Anticipated Benefits
This project integrates translational stress neurobiology with the cognitive neuroscience of 
memory to test novel mechanistic hypotheses regarding stress effects on clinically 
meaningful functions in humans. Building upon the recent development of behaviors that 
map onto different hippocampal mechanisms, we can systematically examine stress effects 
across forms of learning centered on a single brain region. These results will enable a fine-
grained analysis of hippocampal function and its modulation by stress. By revealing the 
susceptibility of different types of learning to stress, these findings have the potential to 
uncover fundamental distinctions between these learning systems that can be leveraged to 
optimize neural network models and generate novel predictions regarding hippocampal 
function. Elucidating this transdiagnostic mechanism also promises significant clinical 
implications, ultimately facilitating the development of targeted pharmacological and 
behavioral therapeutic interventions to combat risks for stress-related psychopathology. 
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3 Study Purpose and Objectives
3.1
Purpose
Stress presents a serious public health problem that has significantly increased during the 
COVID-19 pandemic. One powerful effect of stress is to modulate the structure and function 
of the hippocampus, a crucial brain structure for learning. This modulation may contribute to 
the etiology and maintenance of mental health problems including posttraumatic stress 
disorder and addiction. However, the effects of stress are complex: across species, stress 
both enhances and impairs hippocampal learning. Furthermore, although elegant work in 
rodent models demonstrates distinct stress actions across hippocampal subregions, the 
measures of learning used in humans make translation challenging. To determine the 
mechanisms by which stress alters learning, and to design interventions for negative stress 
effects, there is an urgent need to understand how stress modulates measures of human 
learning that disentangle contributions of hippocampal subregions. Our goal is to determine 
how acute stress enhances and impairs hippocampal learning, providing a basis for 
optimizing treatment of stress-related psychopathology and harnessing the adaptive 
potential of stress in everyday life. 
3.2
Hypothesis
In this study, we will test the hypothesis that acute stress will have divergent effects on two 
hippocampal learning processes: episodic encoding will be impaired by acute stress, 
whereas statistical learning will be enhanced by acute stress. 
3.3
Objectives
The objective of this study is to leverage novel behavioral and neuroimaging assays to 
determine how stress modulates distinct hippocampal learning processes in humans. Using 
a between-subjects design, we will investigate whether exposure to a mild laboratory 
stressor changes the formation of different types of memories; specifically, storing individual 
experiences (episodic encoding) and learning environmental regularities (statistical learning). 
Our central hypothesis is that stress will modulate hippocampal responses and connectivity 
to enhance statistical learning while impairing episodic encoding. The following specific aims 
will be addressed:
Aim 1. Characterize how acute stress affects the relative expression of statistical learning and 
episodic encoding. 
Aim 2. Identify the neural mechanisms by which stress influences statistical learning and 
episodic encoding.
As a secondary objective, we will determine whether individual variability in the magnitude of 
the stress response influences the effects of stress on hippocampal learning.
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4 Study Design
Overview
The in-lab experiments will consist of two testing sessions on two consecutive days. 
Sessions will occur between 12:00-6:00pm to account for circadian fluctuations in cortisol 
(Lupien et al., 2007). On Day 1, participants will be exposed to a stress or control 
manipulation followed by a learning task. On Day 2, participants will be tested for their 
memory. At the end of the experiment, the experimenter will answer any remaining 
questions from the participant.
Participants will provide multiple salivary samples over the course of the experiment. Saliva 
will be collected using salivettes, which participants will be instructed to hold under their 
tongue for two minutes. These will be stored in sterile tubes in a -20 freezer. The samples 
will be exclusively analyzed for cortisol and alpha-amylase concentrations. 
Both behavioral and fMRI studies will follow the same overall design, which is described 
below.
Online studies will follow a similar procedure, excluding the Cold Pressor Test and saliva 
samples (i.e., they will answer intake questionnaires and perform the learning and memory 
tests). Online studies may follow the two day procedure as described below, or all 
procedures may be done in a single session. Additionally, online participants will not be 
assigned to stress or control groups; we will examine how individual differences in stress (as 
measured via questionnaire data) influence learning and memory.
Day 1
Intake Procedures 
After providing written informed consent, participants will be asked about their demographic 
information, medical and psychiatric conditions using self-report forms through Yale’s 
HIPAA-aligned instantiation of Qualtrics (providing data on age, education, menstrual cycle, 
and significant medical history). We will also assess subjective stress, affective state, and 
substance use. These questions will be taken from standardized instruments such as: 
Alcohol Use Disorders Identification Test (Saunders, Aasland, Babor, de la Fuente, & Grant, 
1993); the Positive and Negative Affect Schedule (Watson, Clark, & Tellegen, 1988); 
Perceived Stress Scale (Cohen, Kamarck, & Mermelstein, 1983); Difficulties in Emotion 
Regulation Scale (Gratz & Roemer, 2004); Trier Inventory of Chronic Stress (Petrowski et al 
2020); and Life Events Checklist (Gray, Litz, Hsu & Lombardo 2004); and Menstrual Cycle 
Questionnaire. Participants in fMRI experiments will also complete the MRI safety screening 
form. 
Each participant will be randomly assigned to a stress or control group. The procedures of 
the experiment will be identical for both sets of subjects, with the only difference being 
whether they experience the ice cold water or warm water arm bath (see Cold Pressor Task 
below). See the flowchart below for the general procedure. 
Cold Pressor Test
To induce stress, we will use the Cold Pressor Test (CPT), a widely used procedure to 
provoke mild to moderate pain and stress in both adults and children. It has been used in 
many studies of autonomic reactivity, and hormonal stress responses. The CPT has been 
used successfully with both children and adults without reported adverse effects (Von 
Baeyer et al., 2005; Kowalcyzk et al., 2006; Siegrist et al., 2006; Silverthorn and Michael, 
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2013; Goldfarb et al 2017a,b; Goldfarb et al 2019). The CPT involves participants 
submerging their fingertip to elbow in a bucket of ice cold water placed (0-2 deg C). The 
water exposure is terminated when the experimenter instructs the participant that the test 
has ended (after 3 minutes). This increases the uncontrollable characteristics of the stress 
exposure. Participants will not be told how much time is remaining during the water 
exposure, and use of wrist watches or other time-pieces is not permitted. Prior to the CPT, 
participants may be informed by the experimenter that they will be video recorded during the 
test. This information has demonstrated to induce social stress (Schwabe & Schächinger, 
2018). Although the participants will be video recorded during the CPT, the video data will be 
discarded without being looked at by the experimenter, as the video recording is merely for 
the purpose of further inducing stress.  As a control condition, participants follow the same 
procedure but submerge their arm in warm water (37-40C). Participants in the control 
condition will not be video recorded. The experimenter will read a standardized script with a 
neutral affect (neither encouraging nor intimidating) to inform the participant of the 
procedure. Immediately upon removing their arm from the cold/warm water, ratings of 
subjective stress will be assessed.
Learning Task
Our tasks involve responding to visual or auditory stimuli presented on a screen or tablet. 
The stimuli may differ across experiments. For example, participants may view/hear 
characters, shapes, photographs (e.g., faces, scenes, objects, abstract images), fractals, 
tones, artificial speech, and videos. The stimuli may be neutral in affect, or may be emotional 
(i.e, images from the IAPS picture dataset). The stimuli will be presented as a sequence, 
with certain kinds of stimuli reliably following other kinds of stimuli (allowing for participants 
to learn features of the sequence). Participants are typically required to make an immediate 
judgment about the stimuli, such as detection, naming, or memorization of a target stimulus. 
Responses are typically made by pressing a key on a keyboard or a button on a button box. 
All of our experiments are divided into blocks of trials, and participants are encouraged to 
take breaks between blocks to minimize fatigue. 
Eye tracking 
In the studies involving fMRI, eye gaze and pupil dilation will be acquired throughout the 
scan using an MR-compatible SR Eyelink system at BIC or BrainWorks. 
fMRI Scanning 
In the studies involving fMRI, participants will perform the learning task while being scanned 
with fMRI. Prior to entering the MRI scanner, participants will walk through a metal-detecting 
gate in the hall. Before entering the scanner room, we will pass a high-sensitivity metal 
detecting wand over the body of the participant. 
Participants will be provided with earplugs to protect their hearing from scanner noise. When 
we will be delivering auditory stimuli in some experiments, we will use either earbud 
headphones embedded in earplugs or over-the-ear headphones over earplugs. They will 
also be given a squeeze button or ball and informed that they can squeeze it to 
communicate with the researchers in the event that they feel uncomfortable or need to stop 
at any point. Participants will be given an MRI-compatible button box which can be used to 
provide responses.
Brain images will be collected using a Siemens Prisma 3T scanner at the BIC or BrainWorks 
with the 64-channel head/neck coil. Structural images will be collected to measure the 
participant’s brain anatomy. Functional images will be collected to provide information about 
brain activity while the participant performs tasks. We plan to use the following types of 
sequences (though we may adjust parameters slightly as needed):
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Scout (auto-align localizer): slices = 128, matrix = 256, FOV = 250 mm, resolution = 0.5 x 0.5 
x 7 mm, TR = 8.6 ms, TE = 4 ms, flip angle = 20°, time = 0:14
EPI (functional scans): slices = 90, matrix = 128, FOV = 192 mm, resolution = 1.5 mm iso, 
TR = 1500 ms, TE = 32.6 ms, flip angle = 55°, multiband factor = 6, time = variable 
MPRAGE (T1 structural scan): slices = 192, matrix = 256, FOV = 256 mm, resolution = 1 
mm iso, TR = 2300 ms, TE = 2.27 ms, TI = 900 ms, flip angle = 8°, iPAT = 3, time = 3:54 
TSE (T2 structural scan, partial volume for hippocampal segmentation): slices = 54, matrix = 
384, FOV = 168 mm, resolution = 0.44 x 0.44 x 1.5 mm, TR = 11390 ms, TE = 90 ms, flip 
angle = 150°, time = 3:49 
We may also collect images with the same slice parameters as the EPI using a FLASH 
structural sequence (to improve alignment) and two spin echo field map sequences with 
reversed A-P phase encoding direction (to correct distortions). 
After the scan, the researcher will debrief the participant, thank them, compensate them for 
their participation (if they are not coming back for a second session), and escort them out of 
the facility.
If upcoming fMRI sessions have been booked, all participants will be given the opportunity to 
be booked as a “back-up”. “Back-up” participants arrive at the scan center for the same 
appointment time as an already-booked participant. They then review and sign the consent 
form. If the already-booked participant does not attend the appointment, the “back-up” 
participant will complete the full experimental protocol at that time. If the already-booked 
participant does attend, the “back-up” will be compensated $10, and be scheduled to 
complete the protocol at a later date. 
Day 2
Memory Tasks
Participants will be asked to complete memory tests near the end of the experiment. This 
might include recognition, in which a subject has to indicate whether the stimulus was seen 
before or not, or recall, in which a subject has to provide missing details about the stimulus 
such as the context it was seen in or an associated item that it was paired with. As on Day 1, 
participants will be asked to respond to visual or auditory stimuli presented on a screen or 
tablet, with responses made by pressing a key on a keyboard or a button on a button box. 
Experiments are divided into blocks of trials, and participants are encouraged to take breaks 
between blocks to minimize fatigue. 
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Study procedures
Visit 1
<Day 1>
Visit 1
<Day 1>
Visit 2
<Day 2>
Conduct informed consent process. Intake questionnaires.
Control grp.
Stress group
Saliva sample 1
Cold Pressor Task (cold or warm water, depending on group)
Saliva Sample 2
Rest (in MRI scanner if applicable)
Saliva Sample 3
Behavioral Learning Task (in MRI scanner if applicable)
Saliva Sample 4
Randomize
Saliva sample 5
Memory Test
Saliva Sample 6
Participant debriefing and payment
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4.1
Study Duration
Each participant will complete 2 sessions. The first session will take 1-2 hours and the 
second session will take 0.5-1 hour. We expect the entire study to last 3 years (including 
data analysis).
4.2
Outcome Variables/Endpoints
Behavioral measures of learning: during the learning task, participants will make responses 
to the stimuli viewed on the computer screen. Responses will be analyzed to assess 
learning-related effects (e.g., faster responses for predictable displays).
Behavioral measures of memory: during the memory task, participants will make judgments 
about whether they remember specific displays or sequences of displays. We will analyze 
their accuracy on these tasks to create a memory score.
Cortisol response: Saliva samples will be collected at multiple timepoints throughout the 
experiment. These samples will be assayed to quantify levels of the stress hormone cortisol, 
which will be used to assess basal levels per participant and determine the efficacy of our 
stress induction. 
Alpha-amylase response: Saliva samples will be collected at multiple timepoints throughout 
the experiment. These samples will be assayed to quantify levels of salivary alpha-amylase, 
a proxy for the adrenergic stress response. These will be used to assess basal levels per 
participant and determine the efficacy of our stress induction. 
Subjective measures of stress: Subjective ratings of stress will be collected after the stress 
manipulation to assess individual differences in subjective stress responses.
fMRI BOLD response: For the fMRI experiment, we will be collecting BOLD data for the 
entire brain during the learning task. Various analyses will be performed on these data to 
assess neural correlates related to learning and memory.
Gaze/pupil dilation: For the fMRI experiment, we may also collect eye-tracking data during 
the learning task. Various analyses will be performed on these data to assess proxies for 
noradrenergic responses and signals related to learning and memory.
Questionnaire responses: Questionnaires such as the Perceived Stress Scale will be scored 
to assess participants’ individual differences in baseline stress levels and determine whether 
they influence learning and interact with acute stress.
4.2.1
Primary Outcome Variables/Endpoints
To characterize how acute stress affects the relative expression of different kinds of 
memory, we will measure statistical learning and episodic memory. Statistical learning will be 
assessed using responses/response times during the learning task, as well as from memory 
tests (see above). Episodic memory will be assessed by recognition memory performance. 
We hypothesize that measures of statistical learning will be enhanced following acute stress 
(as measured, e.g., by greater response time benefits during learning) and that measures of 
episodic memory (e.g., later recognition) will be diminished following acute stress.
To identify the neural mechanisms by which stress influences these different kinds of 
memory, we will focus on hippocampal responses measured during fMRI scanning. We 
hypothesize that measures of functional connectivity between hippocampal subregions CA1 
and CA3 will be lower following acute stress (consistent with poorer episodic memory), 
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whereas functional connectivity between subregion CA1 and the entorhinal cortex will be 
higher following acute stress (consistent with better statistical learning). 
4.2.2
Secondary and Exploratory Outcome Variables/Endpoints (if applicable)
To assess whether individual differences in the magnitude of the stress response predict the 
effect of stress on memory, we will leverage both objective and subjective measures of the 
stress response. We will test whether the change in cortisol and alpha-amylase from pre- to 
post-stress induction and subjective measures of stress – in addition to baseline levels of 
stress as measured through questionnaire data – predict the influence of acute stress on our 
neural and behavioral measures of learning and memory. We will also assess whether 
anticipatory noradrenergic responses (via pupil dilation) differ with stress and correspond to 
facilitated learning.
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5 Study Participants
5.1
Study Population
Participants in this study will be healthy individuals aged 18-45. We aim to study this healthy, 
young cohort in order to understand the baseline relationship between stress and memory in 
neurotypical individuals.
5.2
Number of Participants
Approximately five-hundred participants will be enrolled in the experiments. We plan to run 
between two and four behavioral studies (N = 46-138 each, depending on the exact 
parameters of the study) and one fMRI study (N = 100). These numbers were determined 
based on power analyses from past studies of statistical learning and episodic encoding 
(Sherman & Turk-Browne 2020) and acute stress effects on memory (Goldfarb et al 2019).
Participants who do not meet our eligibility criteria as confirmed during recruitment (i.e., self-
reporting that they are out of the age range or ineligible for MRI studies) will not be included 
in the participant count. For each participant who is excluded after their participation (i.e., 
due to responses on an intake questionnaire), we will recruit an additional participant so that 
the total number of usable participants matched the above-stated desired Ns. 
5.3
Eligibility Criteria
In order to be eligible for inclusion in the study, and individual must meet all of the following 
criteria: (1) 18-45 years old, (2) fluent in English, (3) BMI between 18-35.
Any individual who meets any of the following criteria will be excluded from participation in 
this study: (1) meeting current DSM-V criteria for any substance use disorder (except 
caffeine), (2) having current significant medical conditions or psychiatric symptoms requiring 
medication, (3) current use of medications/drugs that interfere with physiological stress 
responses, (4) peri and post-menopausal women, pregnant or lactating women, and those 
with hysterectomies, (5) metal in body (for MRI safety). Menstrual cycle status and detailed 
history will be assessed for female participants. 
5.4
Recruitment Procedures 
Participants will be identified by responding to flyers (see Appendix 1 & Appendix 2), to a 
web or social media posting, or by filling out a form on our lab website. Prospective 
participants will be contacted via e-mail and/or a phone call to confirm their interest and 
eligibility and schedule a session. Only study personnel listed in this protocol will recruit 
participants.
We will send prospective MRI participants the MRI safety screening and consent forms via 
Yale’s HIPAA-aligned instantiation of Qualtrics. Prior to scheduling an fMRI session, we will 
ask the participant if they would have to indicate “yes” to any of the exclusions on the 
screening form. If so, we will ask follow-up questions about this item to determine whether 
they are eligible to participate. This advance screening is intended to avoid scheduling fMRI 
sessions for participants who will be ineligible. Participants will be told that it is optional for 
them to respond to these questions over email or phone, and that we can schedule an in-
person (non-fMRI) session to review the forms instead. All participants will fill out and sign 
the forms via Qualtrics when they come in for a session. For individuals who are deemed 
ineligible, all information will be destroyed immediately.
Eligible participants will be offered the option of being a “back-up” participant, in which case 
they would arrive at the same time as an already-scheduled participant, in addition to directly 
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booking their appointments. All participants will provide consent upon arrival at their first 
scheduled study visit.
5.5
Consent/Assent Procedures/HIPAA Authorization
Only study personnel listed in this protocol will obtain consent. During the session (upon 
arrival to the study site), participants will receive and sign the consent form via Yale’s 
HIPAA-aligned instantiation of Qualtrics. 
Consent forms will describe in detail the study intervention, study procedures, and risks. 
Written documentation of informed consent is required prior to starting any study 
procedures. Consent forms will be IRB-approved and the participant will be asked to read 
and review the document. Back-up participants will be given a separate consent form 
explaining the procedures and compensation.
The person obtaining consent will ensure that the potential subject is able to read and 
comprehend the consent. Comprehension will be assessed throughout the consent process 
and the participant will be given multiple opportunities to ask questions. The investigator will 
not enroll any participants who are determined to have limited decision-making capacity. 
They will have the opportunity to ask questions before and during the session. It will be 
stressed that any participation is voluntary and that consent can be withdrawn at any time. 
The conversation will take place in a private room to assure the participant’s privacy. To 
avoid coercion, financial incentives for participation will be in line with standard subject 
payments. A copy of the informed consent document will be given to the participants for their 
records. 
For online studies, participants will be presented with an online version of the consent form. 
They will be given as much time as they need to read the procedures, and they will indicate 
their consent by clicking an “I consent” button. 
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6 Study Methods/Procedures
6.1
Study Procedures
Each experiment will take place across two sessions on two consecutive days. The two 
sessions will occur 24h apart and will each be conducted between 12-6pm to control for 
circadian fluctuations in cortisol levels (Lupien et al 2007). Participants will be recruited via 
the procedures described in 5.4. 
On Day 1, participants will be greeted by a member of the study personnel and consent will 
be obtained. Participants will be randomly assigned to either the Stress group or the Control 
group. Participants will become acclimated to the study environment and complete intake 
questionnaires. Participants will then provide a saliva sample (#1) to determine basal levels 
of cortisol and alpha-amylase. Participants randomly assigned to the Stress group will then 
undergo the cold pressor test (arm submerged in 0-2C cold water for 3 minutes), while 
participants in the Control group will have their arm submerged in warm water (37-40 C) for 
3 minutes. Participants in the Stress group may be informed that they will be video recorded 
during the task. Then, a second saliva sample (#2) will be acquired.
Participants will then undergo a brief rest period to allow for the cortisol stress response to 
emerge (Shields et al., 2017). The duration of this rest period may differ across experiments 
so that we can assess the influence on the delay between stress and learning on 
subsequent outcomes. Participants will sit silently or watch a neutral video during this period. 
If participants are enrolled in the MRI study, we may collect anatomical and resting state 
fMRI scans during this time.
Following this rest period, an additional saliva sample will be taken (#3), and participants will 
complete the behavioral learning task. Participants will be exposed to a series of displays on 
the computer screen (see section 4) and be asked to make responses on a computer 
interface. After they complete the behavioral task, they will give one more saliva sample 
(#4), and then be dismissed for Day 1.
Day 2 will take place 24 hours later. Participants will again be greeted by a member of the 
study personnel. After giving another saliva sample (#5), they will then complete a series of 
memory tests. Following the test, they will give a final saliva sample (#6). The procedures of 
the study will then be explained to the participant, and the participant will be given the 
opportunity to ask questions about the study design. The participant will then be 
compensated for their participation. 
Research staff will be responsible for implementing the interventions and collecting 
participant data. All study personnel will complete required human research protections 
training prior to the initiation of participant recruitment, and be trained on study protocols, 
recruitment and consenting, intervention and/or data collection procedures, and data 
handling and confidentiality. A Standard Operating Procedures manual will be developed to 
guide the conduct of the study and used in training. The PIs will supervise junior staff and 
provide re-training in the study protocol as needed. 
Online studies will follow a similar procedure, excluding the Cold Pressor Test and saliva 
samples (i.e., they will answer intake questionnaires and perform the learning and memory 
tests). Online studies may follow the two day procedure as described above, or all 
procedures may be done in a single session. Additionally, online participants will not be 
assigned to stress or control groups; we will examine how individual differences in stress (as 
measured via questionnaire data) influence learning and memory.
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Visit Schedule Table 
Recruitment
(Pre-consent)
Visit 1
Day 1
Visit 2
Day 2
Review Eligibility
X
Informed Consent
X
Demographics
X
Questionnaires
X
X
Saliva Samples
X
X
Behavioral Tasks
X
X
fMRI Scanning and eyetracking (if applicable)
X
Randomization
X
Adverse Events Reporting (if applicable)
X
X
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6.1.1
Data Collection
Questionnaire and demographic data will be collected using Yale’s HIPAA-aligned 
instantiation of Qualtrics. Please see section 4 (Intake Procedures) for a list of the validated 
questionnaires that will be used. Licensure/training is not required for the administration of 
these questionnaires.
Behavioral responses will be made on a computer and responses will be recorded with 
custom experiment programming software designed through Matlab’s Psychtoolbox 
(Brainard, 1997) or Python’s Psychopy (Peirce, 2007), programs widely used in 
psychological research. MRI data will be acquired on the Siemen’s 3T Prisma Scanner at 
the BIC or BrainWorks. Data for online studies will be completed on participants’ personal 
computers, and will be accessed through the Prolific or mTurk interface. Responses will be 
recorded with custom experiment programming software designed through Javascript. 
All data will be coded in a de-identified manner and stored in password-protected computer 
files accessible only to the research team. fMRI data will be stored on the secured and 
HIPAA-aligned Milgram computer cluster managed and certified for compliance by the Yale 
Center for Research Computing. Backups of the fMRI data may be burned to DVDs at the 
scanner and locked in a cabinet in the Turk-Browne lab space. Behavioral data (e.g., button 
presses, verbal reports, eye-tracking images) will either be recorded on computers secured 
in the control room and transferred on an encrypted and passcode-protected flash drive to 
computers in the Turk-Browne lab or on a password-protected laptop computer with full disk 
encryption, which will otherwise be kept locked in the Turk-Browne lab space. All video data 
collected during the behavioral task will be discarded without being looked at within seven 
days of a participant’s participation. 
Correspondence with study participants and a spreadsheet linking participant ID codes with 
identifiable information will be kept on a password-protected desktop computer with full disk 
encryption in the locked research coordinator office in the Turk-Browne lab space. Paper 
consent forms will be stored separately from any data and in a locked cabinet in the Turk-
Browne lab space. Electronic consent forms and demographic forms will be stored on the 
secure Yale Qualtrics server, a HIPAA-aligned tool for survey data collection.
6.2
Method of Assignment/Randomization (if applicable) 
Participants will be pseudo-randomly assigned to the experimental groups such that the 
groups do not differ in age and sex. There will be no blinding procedures, as both the 
experimenter and participant will be aware of whether they are receiving the cold or warm 
water treatment. 
6.3
Adverse Events Definition and Reporting
Adverse event means any untoward medical occurrence associated with the use of an 
intervention in humans, whether or not considered intervention-related. 
An adverse event (AE) or suspected adverse reaction is considered "serious" if, in the view 
of either the investigator or sponsor, it results in any of the following outcomes: death, a life-
threatening adverse event, inpatient hospitalization or prolongation of existing 
hospitalization, or a persistent or significant incapacity or substantial disruption of the ability 
to conduct normal life functions. 
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This protocol presents minimal risks to the subjects and Unanticipated Problems Involving 
Risks to Subjects or Others (UPIRSOs), including adverse events, are not anticipated. In the 
unlikely event that such events occur, Reportable Events (which are events that are serious 
or life-threatening and unanticipated (or anticipated but occurring with a greater frequency 
than expected) and possibly, probably, or definitely related) or Unanticipated Problems 
Involving Risks to Subjects or Others that may require a temporary or permanent interruption 
of study activities will be reported immediately (if possible), followed by a written report within 
5 calendar days of the Principal Investigator becoming aware of the event to the IRB (using 
the appropriate forms from the website) and any appropriate funding and regulatory 
agencies. The investigator will apprise fellow investigators and study personnel of all 
UPIRSOs and adverse events that occur during the conduct of this research project through 
regular study meetings. 
6.4
Reaction Management
The stress induction procedure used in this minimal risk study is a physiological stressor, 
which disrupts the body’s homeostasis via exposure to cold water. It is not designed to 
induce emotional stress responses and is unlikely to lead to adverse stress reactions in 
healthy populations, such as the one studied here. In the case of an emergency, 
psychologists at the Yale Stress Center (including PI Dr. Goldfarb) may be contacted to 
speak to the participant.
6.5
Withdrawal Procedures
Participants who withdraw from the study before completion will be given the opportunity to 
ask questions about the study. The data collected from these participants will not be 
analyzed.
6.6
Locations/Facilities
Some behavioral studies will take place in Sheffield-Sterling-Strathcona (SSS) Hall (1 
Prospect Street) or 100 College Street and some will be conducted online, on mTurk or 
Prolific.
The fMRI studies will take place in the FAS Brain Imaging Center in Dunham Lab (10 
Hillhouse Avenue) or BrainWorks (100 College Street).
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7 Statistical Design
The general statistical approach involves examining differences in our outcome measures as 
a function of stress condition (i.e., whether participants experience acute stress prior to the 
learning task or not). Analyses will primarily be conducted with repeated-measures ANOVAs 
(rmANOVA) and t-tests where appropriate. 
7.1
Sample Size Considerations
For the behavioral studies, we aim for an N = 46 per condition. This is consistent with the 
sample size of the study on which this behavioral experiment is based (Sherman & Turk-
Browne, 2020). 
To determine the sample size for the fMRI study, we conducted power analyses based on 
our previous work demonstrating evidence of statistical learning in the hippocampus 
(Sherman et al., 2020). These results indicate that we would need N = 40 participants per 
group to detect neural effects (d = .45, 80% power). Thus, we will recruit 80 participants and 
randomly assign them to Stress (N = 40) or No Stress (N = 40) conditions. 
7.2
Planned Analyses
We will test the hypotheses that: (1) stress enhances statistical learning (rmANOVA; 
facilitated reaction time for predictable items during learning in the Stress vs No Stress 
group); (2) stress enhances retention of statistical learning (t-test; better discrimination of AB 
category pairs in the Stress vs No Stress group); and (3) stress impairs episodic memory (t-
test; overall lower exemplar recognition memory in the Stress vs No Stress group). Although 
there may be a global effect of worse episodic memory in the Stress group, we expect such 
deficits to be driven in part by an interaction with category type (A, B, or X). That is, if Stress 
potentiates statistical learning, these participants would quickly learn to anticipate the B 
category while viewing the preceding A category item. Thus, rather than focusing on 
encoding the A category item, they would be predicting the B category, leading to greater 
competition between encoding and statistical learning (rmANOVA; greater deficits in memory 
for A relative to X items in the Stress group). 
For the fMRI experiment, we will investigate the neural mechanisms underlying stress effects 
on different forms of learning using a combination of connectivity, multivariate, and univariate 
approaches. Specifically, we will test the working hypothesis that stress will have opposite 
effects on neural processes supporting episodic encoding and statistical learning. Based on 
rodent models, we hypothesize that stress will facilitate the function of subregions and 
connections associated with the monosynaptic pathway (MSP) while impairing or sparing the 
function of the trisynaptic pathway (TSP). 
We will test whether stress induces state-level changes in TSP and MSP connectivity by 
comparing background connectivity (Al-Aidroos et al., 2012) from CA1-entorhinal cortex 
(MSP) and CA1-CA2/3/DG (TSP) in Stress vs. No Stress participants. If state-level changes 
are not detected, we will use a different connectivity approach to separate connectivity 
patterns during different trial types. To probe the functional significance of connectivity 
changes, we will perform our recently developed seed connectome-based predictive 
modeling analysis (Goldfarb et al., 2020), using whole-brain CA1 connectivity during 
encoding to predict subsequent memory performance in Stress and No Stress participants. 
To test whether stress amplifies neural signatures of statistical learning, we will use 
multivariate approaches to characterize neural evidence of prediction. Following prior work 
(Sherman & Turk-Browne, 2020), we will train a classifier in the hippocampus (using a linear 
support vector machine implemented in Python’s scikit-learn module) to distinguish between 
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different scene categories. By training the classifier on voxel patterns in the hippocampus 
from the localizer run (in which no statistical regularities are present) to distinguish amongst 
B categories, we can derive a signature of B category to apply to learning runs. The extent 
to which B can correctly be classified during the preceding A item (when B has not yet been 
presented) serves as a neural measure of prediction. If stress amplifies neural signatures of 
statistical learning, we expect to see greater evidence for the predicted category in the 
Stress, relative to No Stress, group. Finally, univariate whole-brain analyses will include 
subsequent memory analyses (Wagner et al., 1998) (contrasting Remembered with 
Forgotten trials from conditions A/B/X) to test how whole brain processes supporting 
memory differ in Stress vs No Stress participants. 
7.2.1
Secondary Objective Analyses (if applicable)
Further exploratory analyses will investigate whether stress-induced changes in learning and 
memory are associated with the magnitude of the stress-induced cortisol and adrenergic 
response by using these measures as covariates in the above analyses. We hypothesize 
that larger stress-induced increases in cortisol are associated with stronger benefits for 
statistical learning and impairments for episodic encoding. In the fMRI study, we will test 
whether stress exposure modulates stimulus-evoked and ITI-evoked pupil dilation, 
processes previously been shown to be modulated by stress exposure and associated with 
subsequent episodic memory (Henckens et al 2009; Qin et al 2012), although the role of 
pupil reactivity in statistical learning is unclear.
7.2.2
Analysis of Subject Characteristics (if applicable)
N/A
Interim Analysis (if applicable)
N/A
7.3
Data Relevance
By examining differences in behavioral and neural measures of hippocampal learning as a 
function of acute stress exposure, we can test our hypothesis that stress has distinct effects 
different forms of hippocampal learning.
7.4
Data Coding
N/A
7.5
Data Analysis Tools
Behavioral data will be analyzed using R. fMRI data will be analyzed using a combination of 
FSL, AFNI and Python.
7.6
Data Monitoring
The PIs are responsible for monitoring the data, assuring protocol compliance, and 
conducting quarterly safety reviews.
7.7
Handling of Missing Data
 All data will be collected and stored electronically. Data will be missing only in the case of a 
technological failure (e.g., a computer error). Participants with incomplete datasets will be 
excluded from the analyses and replaced.
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8 Data/Specimen Handling and Record Keeping
8.1
Subject Data Confidentiality
Participant confidentiality and privacy is strictly held in confidence by the participating 
investigators, their staff, and the sponsor(s)/funding agency. Therefore, the study protocol, 
documentation, data, and all other information generated will be held in strict confidence. 
All research activities will be conducted in as private a setting as possible.
Representatives of the Institutional Review Board (IRB), regulatory agencies or study 
sponsor/funding agency may inspect all documents and records required to be maintained 
by the investigator for the participants in this study. The study site will permit access to such 
records.
The study participant's contact information will be securely stored at each study site for 
internal use during the study. At the end of the study, all records will continue to be kept in a 
secure location for as long a period as dictated by the reviewing IRB, Institutional policies, 
regulatory, or sponsor/funding agency requirements.
Study participant research data, which is for purposes of statistical analysis and scientific 
reporting, will be transmitted to and stored on encrypted and password-protected computers. 
This will not include the participant's contact or identifying information. Rather, individual 
participants and their research data will be identified by a unique study identification number. 
The study data entry and study management systems used will be secured and password 
protected. At the end of the study, all study databases will be de-identified and archived on 
the Yale Milgram server. All video data collected will be stored on a password-protected 
computer and be discarded without being looked at within seven days of a participant’s 
participation. 
8.2
Data Quality Assurance
To ensure data quality, all study personnel will undergo comprehensive training to ensure 
that the study procedures are consistent for all participants. A standard operating procedure 
for the study will be written as a reference for all study personnel. Within each session, 
participants will undergo practice trials prior to the learning task and will be able to ask 
questions to ensure they understand the task.
8.3
Data or Specimen Storage/Security
All data will be coded in a de-identified manner and stored in password-protected computer 
files accessible only to the research team. fMRI data will be stored on the secured and 
HIPAA-aligned Milgram computer cluster managed and certified for compliance by the Yale 
Center for Research Computing. Saliva samples will not be marked with any identifiable 
information and will exclusively be analyzed for levels of cortisol and alpha-amylase. 
8.4
Study Records
All Qualtrics-based consent forms and questionnaires will be stored in the Investigator’s 
Qualtrics account, which can only be accessed by the Investigator through their credentials. 
Paper-based consent forms will be stored in a locked cabinet in the Turk-Browne lab.
8.5
Access to Source
All questionnaires will be Qualtrics-based and will be stored in the Investigator’s Qualtrics 
account, which can only be accessed by the Investigator through their credentials. No other 
clinical or observational data will be collected.
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8.6
Retention of Records
Upon completion of study and data analysis, a professional information protection, storage, 
and disposal company will be retained to dispose of research files and informed consent 
documentation. These data will be destroyed, after being kept for 5 years after the 
completion of the study.
8.7
Data and Safety Monitoring Plan 
The principal investigators are responsible for monitoring the data, assuring protocol 
compliance, and conducting the safety reviews quarterly.  During the review process the 
principal investigators will evaluate whether the study should continue unchanged, require 
modification/amendment, or close to enrollment.
The principal investigators, the Institutional Review Board (IRB), the Brain Imaging Center 
(BIC), or BrainWorks have the authority to stop or suspend the study or require 
modifications.
This protocol presents minimal risks to the subjects and Unanticipated Problems Involving 
Risks to Subjects or Others (UPIRSOs), including adverse events, are not anticipated. In the 
unlikely event that such events occur, Reportable Events (which are events that are serious 
or life-threatening and unanticipated (or anticipated but occurring with a greater frequency 
than expected) and possibly, probably, or definitely related) or Unanticipated Problems 
Involving Risks to Subjects or Others that may require a temporary or permanent interruption 
of study activities will be reported immediately (if possible), followed by a written report within 
5 calendar days of the Principal Investigators becoming aware of the event to the IRB (using 
the appropriate forms from the website) and any appropriate funding and regulatory 
agencies. The investigators will apprise fellow study personnel of all UPIRSOs and adverse 
events that occur during the conduct of this research project through regular lab meetings or 
via email, as they are reviewed by the PIs. The protocol’s research monitor(s), BIC, 
BrainWorks, study sponsors, funding and regulatory agencies, and regulatory and decision-
making bodies will be informed of adverse events such as injury within 5 days of the event 
becoming known to the principal investigators.
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9 Study Considerations
9.1
Institutional Review Board (IRB) Review
The protocol will be submitted to the IRB for review and approval. Approval of the protocol 
must be obtained before initiating any research activity. Any change to the protocol will 
require an approved IRB amendment before implementation.  The IRB will have final 
determination whether informed consent and HIPAA authorization are required.  
Study closure will be submitted to the IRB after all research activities have been completed.    
Other study events (e.g. data breaches, protocol deviations) will be submitted per Yale 
policies.
9.2
Research Personnel Training
All study personnel will complete required human research protections training prior to the 
initiation of participant recruitment, and be trained on study protocols, recruitment and 
consenting, intervention and/or data collection procedures, and data handling and 
confidentiality. A Standard Operating Procedures manual will be developed to guide the 
conduct of the study and used in training. The PIs will supervise junior staff and provide re-
training in the study protocol as needed. 
9.3
Study Monitoring 
The PIs are responsible for monitoring the data, assuring protocol compliance, and 
conducting quarterly safety reviews. During the review process the PIs will evaluate whether 
the study should continue unchanged, require modification/amendment, or close to 
enrollment.
9.4
Unanticipated Problems and Protocol Deviations
A protocol deviation is any noncompliance with the protocol. The noncompliance may be 
either on the part of the participant, the investigator, or the study site staff. As a result of 
deviations, corrective actions are to be developed by the site and implemented promptly.
It is the responsibility of the site investigator to identify and report deviations within 5 working 
days of identification of the protocol deviation. All deviations must be addressed in study 
source documents, reported to the study sponsor, and the reviewing Institutional Review 
Board (IRB) per their policies.
Unanticipated problems involving risks to participants or others include, in general, any 
incident, experience, or outcome that meets all of the following criteria:

Unexpected in terms of nature, severity, or frequency given (a) the research 
procedures that are described in the protocol-related documents, such as the 
Institutional Review Board (IRB)-approved research protocol and informed consent 
document; and (b) the characteristics of the participant population being studied;

Related or possibly related to participation in the research ("possibly related" means 
there is a reasonable possibility that the incident, experience, or outcome may have 
been caused by the procedures involved in the research); and

Suggests that the research places participants or others at a greater risk of harm 
(including physical, psychological, economic, or social harm) than was previously 
known or recognized.
If the study team becomes aware of an unanticipated problem (e.g. data breach, protocol 
deviation), the event will be reported to the IRB by e-mail.
The UP report will include the following information:
Protocol identifying information: protocol title and number, PI's name, and the IRB project 
number;
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
A detailed description of the event, incident, experience, or outcome;

An explanation of the basis for determining that the event, incident, experience, or 
outcome represents an UP;

A description of any changes to the protocol or other corrective actions that have 
been taken or are proposed in response to the UP.
To satisfy the requirement for prompt reporting, UPs will be reported using the following 
timeline:

UPs will be reported to the IRB within 5 days of the investigator becoming aware of 
the event.
9.5
Study Discontinuation
We do not anticipate any circumstances under which the study may be discontinued. This is 
a minimal risk study, and both the Turk-Browne and Goldfarb labs have successfully 
conducted many similar studies. 
9.6
Study Completion
The study is expected to take approximately 2-3 years to complete. The IRB will be notified 
through the IRES system and a closure request will be submitted.
9.7
Conflict of Interest Management Plan 
The independence of this study from any actual or perceived influence, such as by the 
pharmaceutical industry, is critical. Therefore, any actual conflict of interest of persons who 
have a role in the design, conduct, analysis, publication, or any aspect of this trial will be 
disclosed and managed. Furthermore, persons who have a perceived conflict of interest will 
be required to have such conflicts managed in a way that is appropriate to their participation 
in the trial. The study leadership in conjunction with the appropriate conflict of interest review 
committee has established policies and procedures for all study group members to disclose 
all conflicts of interest and will establish a mechanism for the management of all reported 
dualities of interest.
 All investigators will follow the applicable conflict of interest policies.
9.8
Funding Source
We are applying for NIH funding for this study. In the meantime, the study is being funded 
internally by Nick Turk-Browne and Elizabeth Goldfarb’s labs.
9.9
Publication Plan
After data collection and analysis is complete, decisions will be made about the publication 
process. The PIs Goldfarb and Turk-Browne will hold primary responsibility for publishing the 
study results.
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10Appendices
Appendix #
Title
Section
Topic
1
Behavioral Study 
Flyer
Recruitment
Recruitment 
Flyer
2
fMRI Study Flyer
Recruitment
Recruitment 
Flyer
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11List of Tables
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