Spatiotemporal Dynamics of the Human Emotion Network

Overview

The overall goal of this study is to elucidate how emotion network dynamics relate to the behavioral, autonomic, and experiential changes that accompany emotions and to investigate how emotion network dysfunction relates to affective symptoms. Affective symptoms are a common feature of neuropsychiatric disorders that reflect dysfunction in a distributed brain network that supports emotion. How aberrant functioning in a single emotion network underlies a wide range of affective symptoms, such as depression and anxiety, is not well understood. Anchored by the anterior cingulate cortex and ventral anterior insula, the emotion network responds to numerous affective stimuli. The recording of neural activity directly from the cortical surface from individuals is a promising approach since intracranial electroencephalography (iEEG) can provide direct estimates of neuronal populations to map the spatiotemporal dynamics of the emotion network at a millisecond level resolution. This study will exam how activity within emotion network hubs changes during emotions and how emotion network properties make some individuals more vulnerable to affective symptoms than others. A multidisciplinary approach is critical for understanding the dynamic brain network to advance neuroanatomical models of emotions and for guiding the development of novel treatments for affective symptoms.

Detailed description

Intracranial EEG (iEEG) recordings make it possible to obtain direct measures of emotion network dynamics not possible with other methods. This study proposes to conduct a multimodal assessment of emotions in patients with epilepsy who are undergoing surgery for seizure localization. Electrodes will be placed in sites based on the clinical needs of each patient and will include sites within and outside of the emotion network. The research study team will examine measures of behavior, autonomic nervous system (ANS) activity, and subjective experience to continuous iEEG recordings to determine how emotion network dynamics relate to emotions and affective symptoms. Affective symptoms are common in epilepsy, with nearly one third of patients meeting diagnostic criteria for a severe anxiety or depressive disorder during their lifetimes. This clinical population offers a unique opportunity to obtain direct recordings of emotion network activity with concurrent measures of emotion physiology and behavior. The aims of this study seeks to determine how emotion network activity relates to naturalistic affective behaviors (Aim 1), whether we can uncover the unique neural signatures of discrete emotions and examine their relation to task-based measures of emotional reactivity (Aim 2), and whether electrical stimulation of emotion network changes network activity and alters emotions, mood, and anxiety (Aim 3). Together, these aims will help to uncover the neural mechanisms that produce, sense, and regulate emotions. These results should heavily impact the current understanding of the neurobiological systems that underlie affective symptoms and, therefore, will have significant implications for identifying biomarkers of system dysfunction to guide development of new treatments.

Interventions

• Behavioral Viewing visual stimuli and electrical stimulation of the brain
  View emotionally evocative videos and undergo stimulation of brain regions involved in emotion. In a 20-minute block (5 total blocks), eighteen 30-second movie clips will be used to elicit different categories of emotions (sadness, fear, disgust, awe, affection, and amusement). Additionally, each hub of the emotion network will be stimulated to identify areas that generate similar emotional states as those elicited by the videos. Each stimulation trial consists of 3 minutes of 1-3 mA, 50 Hz, 100

Primary outcome measures

• Mean Change from Baseline in Heart Rate [Time frame: During inpatient hospitalization, approximately 4-14 days]
• Mean Change from Baseline in Respiratory Rate [Time frame: During inpatient hospitalization, approximately 4-14 days]
• Mean change from Baseline in Electrodermal Activity [Time frame: During inpatient hospitalization, approximately 4-14 days]
• Mean Facial Expression Activity [Time frame: During inpatient hospitalization, approximately 4-14 days]
• Mean Change from Baseline in Neural Activity within the Emotion Network [Time frame: During inpatient hospitalization, approximately 4-14 days]

Secondary outcome measures (1)

• Mean Subjective Experience [Time frame: During inpatient hospitalization, approximately 4-14 days]

Eligibility criteria

Inclusion criteria

• Participants with epilepsy at UCSF undergoing surgical electrode implantation for seizure localization and
• Participants with electrodes implanted in at least two regions of interest who are willing and able to cooperate with study tasks.

Exclusion criteria

• Participants who lack capacity or decline to provide informed consent,
• Participants who have significant cerebral lesions or
• Participants with cognitive deficits that preclude reliable completion of study tasks.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

N/A

Model

Single group

Masking

Open label

Primary purpose

Basic science

Study locations

United States · 1 center

• University of California, San Francisco — San Francisco

Identifiers

NCT: NCT05152992 · R01MH122431 · R01MH122431

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗