Supporting Decisions With Transcranial Direct Current Stimulation in Healthy Young and Elderly Individuals

Study Overview
=================
Brief Summary
-----------------
Decisions are part of the daily life. On the neuronal level, activity in the dorsolateral prefrontal cortex (dlPFC) is important during complex decisions (e.g., whether something is emotional for a person or not). We apply transcranial direct current stimulation (tDCS) with the aim to increase dlPFC activity and thereby modulate decisions towards emotional content.

Official Title
-----------------
Supporting Decisions With Transcranial Direct Current Stimulation in Healthy Young and Elderly Individuals

Conditions
-----------------
Sham tDCS, Real tDCS

Intervention / Treatment
-----------------
* Device: real anodal transcranial direct current stimulation
* Device: sham transcranial direct current stimulation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Written informed consent Non-smokers Right-handedness Native German speakers or comparable level of fluency Normal or corrected-to-normal vision Exclusion Criteria: Neurological or psychiatric condition (other than diagnosed cognitive impairment) Past head injuries Magnetizable implants History of seizures Current or life-time alcohol or drug abuse Skin diseases tES in the 3 months preceding or during the present study Caffeine 3 hours prior to training

Ages Eligible for Study
-----------------
Minimum Age: 20 Years
Maximum Age: 30 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Participants are allocated to one of 2 groups: real tDCS or sham.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Real tDCS<br>20 min of 1 mA real anodal transcranial direct current stimulation applied via 5x7 cm rubber electrodes over the DLPFC (current density: 0.028 mA/cm2). Additional ramp-up and ramp-down phase at beginning and end of stimulation lasting for 15 s. Electrodes remain attached to the participant's head for the duration of the decision task. | Device: real anodal transcranial direct current stimulation<br>* A neuroConn DC-Stimulator PLUS (neuroCare Group, Ilmenau, Germany) will be used.<br>|
| Sham Comparator: Sham tDCS<br>30 s of 1 mA anodal tDCS applied via 5x7 cm rubber electrodes over the DLPFC (current density: 0.028 mA/cm2). Additional ramp-up and ramp-down phase at beginning and end of stimulation lasting for 15 s. Electrodes remain attached to the participant's head for the duration of the decision task. | Device: sham transcranial direct current stimulation<br>* A neuroConn DC-Stimulator PLUS (neuroCare Group, Ilmenau, Germany) will be used.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Influence of Stimulation on the Decisions | Number of words which were rated as positive or negative. | 10 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Profile of Mood States (POMS; before stimulation) | Changes in the subjective measure mood, assessed with questionnaire Scores for each item is recorded as 0 for not at all up to 6 for very strong. A Total Mood Disturbance (TMD) score is calculated by summing the totals for the negative subscales dejection (14 items), fatigue (7 items) and discontent (7 items) and then subtracting the total for the positive subscale zest (7 items). | 3 minutes | 
| Profile of Mood States (POMS; after stimulation) | Changes in the subjective measure mood, assessed with questionnaire Scores for each item is recorded as 0 for not at all up to 6 for very strong. A Total Mood Disturbance (TMD) score is calculated by summing the totals for the negative subscales dejection (14 items), fatigue (7 items) and discontent (7 items) and then subtracting the total for the positive subscale zest (7 items). | 3 minutes | 
| Positive and Negative Affect Schedule (PANAS; before stimulation) | Changes in the subjective measure mood, assessed with self-report questionnaire divided into two mood scales. One scale measures a person's positive emotion and the other scale measures the negative. Each segment has ten terms, which can be rated on a scale of 1 to 5 to indicate the extent to which the respondent agrees that this applies to him (higher values means higher agreement). | 2 minutes | 
| Positive and Negative Affect Schedule (PANAS; after stimulation) | Changes in the subjective measure mood, assessed with self-report questionnaire divided into two mood scales. One scale measures a person's positive emotion and the other scale measures the negative. Each segment has ten terms, which can be rated on a scale of 1 to 5 to indicate the extent to which the respondent agrees that this applies to him (higher values means higher agreement). | 2 minutes | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
tDCS