The Emergence of Abstract Structure Knowledge Across Learning and Sleep
Phase: NA
Conditions: Memory Consolidation
Sponsor: University of Pennsylvania

 
 
 
 
 
Grant Title: The emergence of abstract structure knowledge across learning and sleep 
 
NCT number: NCT05746299 
 
Date: November 11, 2021 
 
 
 

Aim 1
Aim 2
4.1 Brief Summary
4.1
Brief Summary
The objective of this study is to determine whether learning a 
category with a certain structure in Stage 1 improves learning of 
a new category with the same structure in Stage 2. The primary 
endpoint is accuracy on the missing feature task in Stage 2. 
The objective of this study is to evaluate the contribution of sleep to the 
consolidation of abstract structural representations. The primary endpoint is 
accuracy in the missing feature task in Stage 2, administered after the delay 
period. 
4.2 Study Design
4.2.a
Narrative Study Description
Participants will be randomly assigned to a Congruent or 
Incongruent Structure Group.  The intervention consists of a 
missing feature task in Stage 1 in which each participant learns a 
novel category whose structure is determined by their assigned 
group. In Stage 2, we will use another missing feature task to 
expose participants to a new category whose structure is 
identical to the category learned by the Congruent group in Stage 
1.  We will assess the effect of our intervention by comparing 
accuracy on the missing feature task across groups in Stage 2. 
Our planned sample size of N =100 results in statistical analyses 
with N =50 which is sufficient to detect our expected effects. 
Aim 2 includes Stage 1, a delay, and Stage 2. Participants are assigned to 
different experimental conditions such that some particpants learn only Lattice 
categories in Stage 1 (Incongruent) while others are exposed to a Modular 
category (Congruent). Participants are also assigned to Awake or Sleep groups.  
Categories in Stage 1 are paired with different auditory tones to be used later in 
TMR in the sleep groups. All participants learn a new Modular category in Stage 
2. The Awake participants (Incongruent and Congruent) remain awake during the 
2 hour delay between Stage 1 and 2.   Sleep participants are given a nap 
opportunity during the delay while sleep stages are monitored with EEG. For 
particpants who learned a Modular as well as a Lattice category in Phase 1, TMR 
will be used to selectively activate the Lattice (Incongruent) or Modular 
(Congruent) category. Participants in the Sleep Control group learned two Lattice 
categories in Phase 1 one of which will be reactivated with TMR.  We will assess 
the effect of our intervention by comparing missing feature task accuracy in 
Stage 2 across groups. Accounting for an expected 20% attrition rate in the sleep 
groups, we plan to collect data from 173 participants, resulting in a final planned 
sample size of N =150. This results in statistical analyses with N =30 which is 
sufficient to detect our expected effects, based on previous studies using these 
methods. 
4.2.b
Primary Purpose
Basic Science
Basic Science
4.2.c
Interventions
Intervention Type
Behavioral
Behavioral
Name
Learning either a Modular or Lattice category in Phase 1
Awake vs. Sleep, Lattice vs. Modular category in Phase 1, and TMR for either 
abstract Modular or Lattice structure during the sleep period
Description
Participants will either learn a Modular or a Lattice category in 
Phase 1. Then all particpants will learn a new Modular category 
in Phase 2. Ability to learn the new Modular category will be 
assessed to determine effect of intervention. 
The Awake vs. Sleep intervention determines whether participants remain awake 
or take a nap during the delay period. The Lattice vs. Modular intervention 
determines whether participants learn two Lattice categories in Phase 1, or one 
Lattice and one Modular category. The TMR intervention determines whether 
TMR is used to reactive a Lattice or Modular category during the nap session. 
After the delay, ability to learn a new Modular category in Phase 2 will be 
assessed to determine effect of interventions.  
4.2.d
Study Phase
Other
Other
4.2.e
Intervention Model
Parallel: Participants will either learn a Modular or a Lattice 
concept in Phase 1.
Parallel: Participants will be assigned to either an Awake-Congruent, Awake-
Incongruent, Sleep-Congruent, Sleep-Incongruent, or Sleep-Control group. 
Number of Arms
2
5
4.2.f 
Masking
Participant, investigator
Participant
4.2.g
Allocation
Randomized
Randomized
Enrollment
100
173
4.3 Outcome Measures
4.3 Name
Structure knowledge for a new Modular category in Stage 2.
Structure knowledge for a new Modular category in Stage 2. 
Type
Accuracy
Accuracy
Time Frame
Final accuracy is collected in a missing feature task which occurs 
25 minutes after the experiment begins and takes 25 minutes to 
complete. Stage 1 and Stage 2 will take 50 minutes to complete. 
Final accuracy is collected in a missing feature task which occurs 2 hours and 50 
minutes after the experiment begins and takes 25 minutes to complete. Stage 1, 
Stage 2, and the intervening delay period will take 3 hours and 15 minutes to 
complete. 
Brief Description
The outcome measure is accuracy (0-100%) on the missing 
feature task in Stage 2. 
The outcome measure is accuracy (0-100%) on the missing feature task in Stage 
2. 
4.4 Statistical Design and Power 
# of subjects
100
150
Expected effect size
0.85
0.85
Power
0.98
0.85
Statistial methods
T-test comparing accuracy between groups (N =50 each group)
T-test comparing accuracy between groups (N =30 each group)
4.5 Subject Participation Duration 
Time to complete study 
1 hour
3.5 hours
4.6 FDA-regulated invervention?  
Yes/No
No   
No   
4.7 Dissemination Plan