Health TrialsbyHealthPanel

Exploring the Role of the Prefrontal Cortex in Decision-Making

ConditionsDepressive Disorder, Major Depressive DisorderHealthy VolunteerAging
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age20-75
SponsorUniversity of Bern

About this trial

The goal of this study is to examine whether high-definition transcranial direct current stimulation (HD-tDCS) can influence decision-making for emotionally valenced content in younger and older adults, with or without major depression.

The main questions are:

In healthy adults, does brain stimulation modulate how people respond to emotionally valenced content during a decision-making task? What happens in the brain during modulation? Do these effects differ between younger and older adults?

In adults with depression, does brain stimulation help shift attention towards positive content during the task? What happens in the brain? Are these effects moderated by age (younger vs. older adults)?

The investigators will compare participants who receive real stimulation to those who receive sham (placebo) stimulation.

Participants will:

Receive high-definition transcranial direct current stimulation (HD-tDCS) of the dorsolateral prefrontal cortex (DLPFC)

Perform a decision-making task involving emotionally valenced words

Complete the task while undergoing a brain scan using ultra-high field 7 Tesla magnetic resonance imaging (MRI) to measure brain activity

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

Written Informed Consent

Age between 20-40 or 60-75 years

Fluent in German

Normal or corrected-to-normal vision

Disqualifiers

History of neurological disorders

History of psychiatric disorders

Use of psychotropic medication

Presence of magnetizable implants

Trial design

Design model

Parallel

Treatments tested in this trial

  • Active high-definition transcranial direct current stimulation (HD-tDCS) - anodal F3/F4

    Device

    Participants receive anodal HD-tDCS targeting the left or right DLPFC (F3/F4).

  • Sham high-definition transcranial direct current stimulation (HD-tDCS) - anodal F3/F4

    Device

    Participants receive sham HD-tDCS targeting the left or right DLPFC (F3/F4). The device mimics the sensation of stimulation without delivering active current.

  • Active high-definition transcranial direct current stimulation (HD-tDCS) - anodal F3/ kathodal F4

    Device

    Participants receive anodal HD-tDCS targeting the left DLPFC (F3) and cathodal stimulation targeting the right DLPFC (F4).

  • Sham high-definition transcranial direct current stimulation (HD-tDCS) - anodal F3/ kathodal F4

    Device

    Participants receive sham HD-tDCS targeting the left DLPFC (F3) and right DLPFC (F4). The device mimics the sensation of stimulation without delivering active current.

Treatment groups

444 Participants
are divided into 4 treatment groups
Group A: Active Stimulation (Healthy)Experimental treatment 1 intervention
Group B: Sham Stimulation (Healthy)Sham comparator 1 intervention
Group C: Active Stimulation (Patient)Experimental treatment 1 intervention
Group D: Sham Stimulation (Patient)Sham comparator 1 intervention

Trial outcomes

Primary outcomes

1

Blood-oxygen-level-dependent (BOLD) signal changes during task-based functional magnetic resonance imaging (fMRI)

Blood-oxygen-level-dependent (BOLD) signal changes will be measured using ultra-high field functional magnetic resonance imaging (fMRI) during a cognitive decision-making task designed to engage prefrontal cortex regions associated with cognitive control and decision making. Structural T1-weighted and T2-weighted images will also be acquired for anatomical localization and normalization. Primary regions of interest (ROIs) include the dorsolateral prefrontal cortex (DLPFC), subgenual anterior cingulate cortex (sgACC), amygdala, and hippocampus.

Time frame
During study visit; measured continuously during the 20-minute stimulation period
2

GABA concentration (baseline)

Magnetic resonance spectroscopy (MRS) will be used to measure Gamma-aminobutyric acid (GABA) concentrations in regions of interest at baseline. The goal is to examine stimulation-related neutransmitter changes.

Time frame
During study visit; during a 9-minute magnetic resonance spectroscopy (MRS) session performed up to 10 minutes prior to the 20-minute stimulation period
3

GABA concentration (after stimulation)

Magnetic resonance spectroscopy (MRS) will be used to measure Gamma-aminobutyric acid (GABA) concentrations in regions of interest after HD-tDCS. The goal is to examine stimulation-related neutransmitter changes.

Time frame
During study visit; within 1 minute after the 20-minute stimulation period, during a 9-minute MRS scan
4

Glutamate concentration (baseline)

Magnetic resonance spectroscopy (MRS) will be used to measure Glutamate concentrations in regions of interest at baseline. The goal is to examine stimulation-related neutransmitter changes.

Time frame
During study visit; during a 9-minute magnetic resonance spectroscopy (MRS) session performed up to 10 minutes prior to the 20-minute stimulation period

Secondary outcomes

1

Positive Affect measured by PANAS (baseline)

Positive Affect will be assessed using the Positive Affect subscale of the Positive and Negative Affect Schedule (PANAS). This subscale includes 10 items reflecting positive emotions. Each item is rated on a 5-point Likert scale. The sum score ranges from 10 to 50, with higher scores indicating greater levels of positive affect.

Time frame
During study visit; at baseline, up to two hours before the 20-minute stimulation period
2

Negative Affect measured by PANAS (baseline)

Negative Affect will be assessed using the Negative Affect subscale of the Positive and Negative Affect Schedule (PANAS). This subscale includes 10 items reflecting negative emotions. Each item is rated on a 5-point Likert scale. The sum score ranges from 10 to 50, with higher scores indicating greater levels of negative affect.

Time frame
During study visit; at baseline, up to two hours before the 20-minute stimulation period
3

Positive Affect measured by PANAS (after stimulation)

Positive Affect will be assessed using the Positive Affect subscale of the Positive and Negative Affect Schedule (PANAS). This subscale includes 10 items reflecting positive emotions. Each item is rated on a 5-point Likert scale. The sum score ranges from 10 to 50, with higher scores indicating greater levels of positive affect.

Time frame
During study visit; after stimulation, up to 1 hour
4

Negative Affect measured by PANAS (after stimulation)

Negative Affect will be assessed using the Negative Affect subscale of the Positive and Negative Affect Schedule (PANAS). This subscale includes 10 items reflecting negative emotions. Each item is rated on a 5-point Likert scale. The sum score ranges from 10 to 50, with higher scores indicating greater levels of negative affect.

Time frame
During study visit; after stimulation, up to 1 hour

Other outcomes

1

Verbal intelligence measured by Wortschatztest (WST)

The Wortschatztest (WST) is a standardized test assessing verbal intelligence by measuring vocabulary knowledge in German. It is administered to account for participants' baseline language ability, helping to control for individual differences in German word knowledge that may affect performance in the decision-making task. The maximum possible score is 42, with higher scores indicating better vocabulary knowledge.

Time frame
During study visit; at baseline, up to two hours before the 20-minute stimulation period
2

Number of (participants with) adverse effects

Participants report adverse effects using the Adverse Effects Questionnaire. They indicate the presence and severity of possible adverse effects related to transcranial direct current stimulation (tDCS), including headache, neck pain, scalp pain, tingling, itching, burning, drowsiness, and concentration difficulties. Severity is rated on a scale from none, mild, moderate, to strong. Participants also report the perceived duration of each sensation and whether they attribute it to the stimulation. Open responses for any additional sensations are collected.

Time frame
During study visit; after stimulation, up to 1 hour

Sponsors and contacts

Click on the lead sponsor to view all of their trials.

University of Bern

Lead sponsor

ki:elements

Collaborator

Source ClinicalTrials.gov
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