Localization of the Reward Positivity to ACC

NCT04684797 | Unknown DMC

• 1 other identifier: BC-09088
• Study Type: interventional
• Target: 40
• Locations: 1 country
• Sites: 1

Brief Summary

The exact function of the anterior cingulate cortex (ACC) is one of the largest riddles in cognitive neuroscience and a major challenge in mental health research. ACC dysfunction contributes to a broad spectrum of neurological and psychiatric disorders, such as depression, ADHD, Parkinson's disease, OCD and many others, but nobody knows what it actually does. Recently a new theory has been developed about ACC function; the HRL-ACC (Hierarchical Reinforcement Learning Theory of ACC). This theory proposes that the ACC selects and motivates high-level tasks based on the principles of hierarchical reinforcement learning. The ACC associates values with tasks, selects the correct tasks and applies control over other neural networks (such as the dorsolateral prefrontal cortex and basal ganglia), which execute the tasks. The values of these tasks are attributed based on "reward prediction error signals", which are sent from the midbrain dopamine system to the ACC. These signals can be recorded using scalp-EEG as an "event-related brain potential" (ERP), which is called the "reward positivity". Until this day, the exact origin of the reward positivity is not yet known. Studies have delivered strong indirect evidence that the reward positivity is generated in the ACC. However, there is an important lack of direct evidence to support this hypothesis. The goal of this study is to provide direct evidence that the reward positivity is generated in the ACC by letting a group of patients with refractory epilepsy perform the virtual T-maze task (which is known to elicit reward positivity) and simultaneously recording intracranial video-EEG.

Conditions

Refractory Epilepsy

Keywords

Anterior Cingulate Cortex; Reward positivity

Outcome Measures

Primary Outcomes (1)

• Distribution of reward positivity amplitude

  Calculation of amplitude of reward positivity ERP-component recorded by intracranial electrodes and scalp-distribution of amplitude across all subjects

  Date of inclusion to date of second session (about one month)

Secondary Outcomes (1)

• Location in brain most likely to represent source of reward positivity

  Date of inclusion to date of second session (about one month)

Study Arms (1)

Intervention group

EXPERIMENTAL

Each participant will undergo two sessions, consisting of performing the virtual T-maze task, scalp-EEG recording and/or intracranial video-EEG recording.

Behavioral: Virtual T-maze task

Interventions

Virtual T-maze task BEHAVIORAL

Patients will have to perform the virtual T-maze task, which is known to elicit reward positivity. During this task, the patients will see a virtual T-maze on a computer screen and have to choose at every junction whether they go right or left. Depending on the direction they choose, they either get positive or negative feedback (reward or no reward). This feedback is chosen completely at random, on a 50% reward/50% no reward basis.

Intervention group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years or older
• Patients with refractory epilepsy
• Planned hospitalization at CNM for invasive video-EEG recording with subdural, epidural and/or depth electrodes
• Patients have to be able to give informed consent themselves
• Imaging after placement of electrodes (CT and/or MRI) has to be available

You may not qualify if:

• Patients known with dementia or severe cognitive and/or psychiatric disorders that makes it impossible for patients to participate in this study
• Active alcohol and/or drug abuse

Sponsors & Collaborators

• University Hospital, Ghent: lead
• University Ghent: collaborator

Study Sites (1)

Department of Neurology, University Hospital Ghent

Ghent, Oost-Vlaanderen, 9000, Belgium

RECRUITING

MeSH Terms

Conditions

Drug Resistant Epilepsy

Condition Hierarchy (Ancestors)

Epilepsy; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases

Study Officials

• Alfred Meurs, MD PhD

  University Hospital Ghent, Department of Neurology

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Alfred Meurs, MD PhD

CONTACT

+3293326482; alfred.meurs@ugent.be

Joyce Oerlemans

CONTACT

+3293325607; joyce.oerlemans@ugent.be

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 21, 2020
• First Posted: December 28, 2020
• Study Start: March 4, 2021
• Primary Completion: September 30, 2024
• Study Completion: September 30, 2024
• Last Updated: January 5, 2024

Record last verified: 2024-01

Locations

BE (1)