Trial Outcomes & Findings for Modulation of Emotion Perception in Humans Via Amygdala Stimulation (NCT NCT05292183)
NCT ID: NCT05292183
Last Updated: 2025-09-22
Results Overview
Valence of each image is assessed by each subject using a Likert-type rating scale with a range of 1 to 7, where 1 represents most negative valence, 4 as neutral, and 7 as most positive. Valence categories are defined in the following manner: negative = 1.0 to 3.0, neutral = 3.1 to 5.0, negative = 5.1 to 7.0. Activation is measured by gamma frequency power (mµV²/30-100 Hz) at 0-1000 msec following image presentation in the basolateral amygdala electrode contact and compared to baseline defined as -500 msec to 0 of image presentation. Gamma power is transformed to z-score (baseline to following image presentation) for individual observations. Z-score of 0 indicates no change from baseline. Positive z-score indicates activation of the basolateral amygdala compared to baseline. Gamma frequency range is defined as 30-100 Hz in intracranial EEG. Power was estimated via a multitaper time-frequency transformation approach. Statistics was done using linear-mixed effects models (LMEs).
COMPLETED
NA
16 participants
0 to 1000 MS following image presentation
2025-09-22
Participant Flow
Of 15 patients who completed the study, EEG data was of adequate quality for analysis for four (4) patients, behavioral data with amygdala stimulation was available for nine (9) patients.
Participant milestones
| Measure |
Entire Study Population
This is the group that was recruited and were able to complete testing
|
|---|---|
|
Overall Study
STARTED
|
16
|
|
Overall Study
COMPLETED
|
15
|
|
Overall Study
NOT COMPLETED
|
1
|
Reasons for withdrawal
| Measure |
Entire Study Population
This is the group that was recruited and were able to complete testing
|
|---|---|
|
Overall Study
Adverse Event
|
1
|
Baseline Characteristics
Modulation of Emotion Perception in Humans Via Amygdala Stimulation
Baseline characteristics by cohort
| Measure |
The Entire Study Population
n=15 Participants
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 and no stimulation. All participants received sham and actual stimulation, however, the order in which the stimuli (with or without stimulation) were presented to the participants was computer randomized. The order in which the stimuli were presented was unique to each individual participant
Electrical Stimulation: We will use a computer randomized stimulation of specific areas in the amygdala while showing a computer randomized set of pictures.
No Electrical stimulation: we will use a computer randomized sham stimulation of specific areas in the amygdala while showing a computer randomized set of pictures
|
|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=5 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
15 Participants
n=5 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=5 Participants
|
|
Sex: Female, Male
Female
|
6 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
9 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
1 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
14 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Black or African American
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
White
|
14 Participants
n=5 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=5 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
1 Participants
n=5 Participants
|
PRIMARY outcome
Timeframe: 0 to 1000 MS following image presentationPopulation: Electrophysiological data is available in 4 participants.
Valence of each image is assessed by each subject using a Likert-type rating scale with a range of 1 to 7, where 1 represents most negative valence, 4 as neutral, and 7 as most positive. Valence categories are defined in the following manner: negative = 1.0 to 3.0, neutral = 3.1 to 5.0, negative = 5.1 to 7.0. Activation is measured by gamma frequency power (mµV²/30-100 Hz) at 0-1000 msec following image presentation in the basolateral amygdala electrode contact and compared to baseline defined as -500 msec to 0 of image presentation. Gamma power is transformed to z-score (baseline to following image presentation) for individual observations. Z-score of 0 indicates no change from baseline. Positive z-score indicates activation of the basolateral amygdala compared to baseline. Gamma frequency range is defined as 30-100 Hz in intracranial EEG. Power was estimated via a multitaper time-frequency transformation approach. Statistics was done using linear-mixed effects models (LMEs).
Outcome measures
| Measure |
Gamma Power in the Amygdala According to Valence Category
n=4 Participants
This measure reflects changes in the activation of the amygdala when viewing images of specific emotional valence across all subjects. In our study, activation on intracranial EEG is measured by change in the power of the gamma band. This band is defined as frequency ranges from 30-100 Hz in intracranial EEG. An increase in gamma power reflects increased local neuronal activity during the cognitive process in question. Here we present neutral, positive, and negative valence images and determine change in gamma power for each valence category. Significant changes in gamma power from baseline is measured as z-score compared to baseline.
|
|---|---|
|
Z-score Gamma Power in Amygdala Per Valence Category
Gamma power positive images
|
1.21 z-score
Standard Deviation 0.23
|
|
Z-score Gamma Power in Amygdala Per Valence Category
Gamma power, negative valence images
|
1.88 z-score
Standard Deviation 0.78
|
|
Z-score Gamma Power in Amygdala Per Valence Category
Gamma power, neutral images
|
1.24 z-score
Standard Deviation 0.24
|
PRIMARY outcome
Timeframe: Valence ratings were assessed immediately following the viewing of each image during performance of the task.Population: These patients represent recruited patients that underwent stimulation of the amygdala during viewing of images of different valence.
Here we assess the effect of basolateral amygdala stimulation on valence ratings. Participants rate the emotional valence of each image in a Likert scale range of 1-7 (1= maximum negative valence, 4=maximum neutral valence, and 7 maximum positive valence) for each of the 96 images. We randomly apply electrical stimulation during perception and of 50% of the images presented. We analyze the effect of stimulation on image rating in the following manner: we grouped the images into three categories, negative (1 to 3), neutral (3.1 to 5), and positive (5.1 to 7) based on subject specific ratings. 2. We then used a multivariate model to assess the effect of stimulation on perception of neutral, negative, and positive categories across 9 patients.
Outcome measures
| Measure |
Gamma Power in the Amygdala According to Valence Category
n=9 Participants
This measure reflects changes in the activation of the amygdala when viewing images of specific emotional valence across all subjects. In our study, activation on intracranial EEG is measured by change in the power of the gamma band. This band is defined as frequency ranges from 30-100 Hz in intracranial EEG. An increase in gamma power reflects increased local neuronal activity during the cognitive process in question. Here we present neutral, positive, and negative valence images and determine change in gamma power for each valence category. Significant changes in gamma power from baseline is measured as z-score compared to baseline.
|
|---|---|
|
Effect of Amygdala Stimulation on Perception of Valence
Neutral no stimulation
|
3.27 units on a scale
Standard Deviation 0.78
|
|
Effect of Amygdala Stimulation on Perception of Valence
Neutral stimulation
|
3.64 units on a scale
Standard Deviation 0.48
|
|
Effect of Amygdala Stimulation on Perception of Valence
Positive valence; no stimulation
|
5.26 units on a scale
Standard Deviation 0.67
|
|
Effect of Amygdala Stimulation on Perception of Valence
Positive valence; stimulation
|
5.08 units on a scale
Standard Deviation 0.94
|
|
Effect of Amygdala Stimulation on Perception of Valence
Negative valence, no stimulation
|
2.02 units on a scale
Standard Deviation 0.66
|
|
Effect of Amygdala Stimulation on Perception of Valence
Negative valence, stimulation
|
2.08 units on a scale
Standard Deviation 0.59
|
Adverse Events
Stimulation
No Stimulation
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Stimulation
n=15 participants at risk
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.
Electrical Stimulation: We will use a computer randomized stimulation of specific areas in the amygdala while showing a computer randomized set of pictures.
|
No Stimulation
n=15 participants at risk
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.
|
|---|---|---|
|
Respiratory, thoracic and mediastinal disorders
Covid-19 Infection
|
6.7%
1/15 • Number of events 1 • during testing sessions for this study or 1 day
|
6.7%
1/15 • Number of events 1 • during testing sessions for this study or 1 day
|
|
Nervous system disorders
Seizure
|
6.7%
1/15 • Number of events 1 • during testing sessions for this study or 1 day
|
6.7%
1/15 • Number of events 1 • during testing sessions for this study or 1 day
|
Additional Information
Dr. Krzysztof Bujarski
Dartmouth-Hitchcock Medical Center
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place