Modulation of Emotion Perception in Humans Via Amygdala Stimulation

Dartmouth Health

Status: Completed

Conditions: Refractory Epilepsy

Treatments: Other: Electrical Stimulation

Study type: Interventional

Funder types: Other; NIH

Identifiers

NCT05292183

STUDY02001399

1R21MH124674-01A1 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

This study will enroll patients with epilepsy who are being evaluated for epilepsy surgery and have intracranial EEG electrodes. In this study, the aim is to record brain signals from areas important in social and emotional processing and to understand how electrical brain stimulation - called neuromodulation - affects such processing. Patients enrolled in this study will be asked to view images depicting a variety of emotionally positive, negative, or neutral themes. As the patient views these images, a small amount of imperceptible and painless electric current will be used to map function of certain parts of a human brain. The overarching goal of the study is to determine if neuromodulation can be used in certain areas of the brain to treat cognitive disorders such as memory loss and post-traumatic stress disorder.

Full description

One to two study tasks will be performed by each participant to help us understand how the brain processes emotion and how stimulation effects emotional processing.

These study tasks will last up to several minutes each, and generally require participants to view pictures while EEG recordings are made from the electrodes placed in specific areas of the brain. The routine video/EEG monitoring and brain function testing should not be disrupted or prolonged by the study testing, and if a participant has a seizure during the testing, it will be recorded as usual for review by participant's providers.

The following study procedures will likely be carried out in each individual case:

1. Recording from areas important in social and emotional processing.

   A computer monitor will be used to present pictures of people engaged in social interaction. Additionally, the researchers will present individual participants with well standardized tasks designed to understand the nature of emotions. Some of these images may be emotionally disturbing. Should participants become uncomfortable with viewing such images, participants would be provided with a choice to not participate in this study.

2. Using brain stimulation to map function of certain parts of your brain.

   A brain stimulator will be used -normally used to map where important brain regions are located-to understand new functions of the brain. Each participant will be presented with pictures on a computer screen. As participant(s) views these pictures, the brain stimulator may be activated (this is not something that is felt by a person) and an electrical stimulation through the implanted electrodes will be delivered to specific regions of the brain. Research team will be measuring how brain stimulation may affect each individual's emotional response to a specific stimulus.

3. Completing the Emotion Self-Rating (ESR) Scale.

This questionnaire will be given to ensure the stimulation doesn't increase any unpleasant emotional experience for participants. This will take place before and during the stimulation of a specific part of the brain.

Enrollment: 16 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age of 18 years or older
• FSIQ 75 and above or any equivalent test of generalized intelligence as determined by the PI to adequately predict engagement in the task
• Able to give independent consent for participation in the study

Exclusion criteria

• Additional neurological disorders (such as dementia, stroke, brain tumor, etc.)
• Any psychiatric condition that would limit their ability to provide consent and/or perform study tasks within normal limits. This would be based on presurgical psychiatric assessment.
• Anything else, that in the opinion of the principal investigator, might preclude them from participating in the study

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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16 participants in 2 patient groups

Stimulation

Experimental group

Description:

This part will include 24 randomly chosen images from each of four categories (total of 96 images varying in valence and arousal) and will be presented block-randomized amygdala stimulation.

Treatment:

Other: Electrical Stimulation

No stimulation

No Intervention group

Description:

This part will include 24 randomly chosen images from each of four categories (total of 96 images varying in valence and arousal) and will be presented without amygdala stimulation.