The Computational and Neural Mechanisms Linking Decision-making and Memory in Humans

Learning to make good decisions in the present, and accurately recalling events and information from the past, are critical aspects of human cognition that are often impaired in many psychiatric disorders. This project aims to identify the how the choices individuals make influence what, and how, people remember by combining disparate techniques in computational modeling and direct brain recordings in human subjects. The researcher developed a dual-task paradigm, probing how decisions in one task affect immediate recognition memory. To examine the neural mechanisms underlying model-free RL's influence on memory, the researcher will record local field potential (LFP) and single neuron activity in various brain regions as epilepsy patients perform the proposed task. The results of this project will identify specific neurocomputational mechanisms unifying decision-making and memory processes.

Study Overview

• Status: Recruiting
• Conditions: Memory, Short-Term
• Intervention / Treatment: Behavioral: Value-manipulation

• Study Type: Interventional
• Enrollment (Estimated): 25
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Salman E Qasim, PhD; Phone Number: 212-824-9531; Email: salman.qasim@mssm.edu

Study Locations

• United States
  • New York
    • New York, New York, United States, 10024
      • Recruiting
      • Mount Sinai West
      • Principal Investigator: Salman E Qasim

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Has seizure activity which is deemed non-responsive to standard pharmacological intervention(s), as determined by treating Neurologist and established clinical practices
• Has elected to receive clinically indicated intracranial EEG (electrocorticography (ECoG), stereoelectroencephalography (SEEG)) and/or temporal responsive neurostimulation (RNS) for medication-refractory epilepsy outside of this research study, as determined by treating clinician(s) and per current clinical practice
• Capacity to provide written informed consent
• Language proficiency in English or Spanish
• Willing and able to comply with all study-related procedures

Exclusion Criteria:

• History of psychosis, such as in the context of depressive or manic episode.
• Active suicidal ideation with intent, suicide attempt within the last six months, or other serious suicide risk
• Inability to provide informed consent or reliably participate in study assessments, as per the Montreal Cognitive Assessment (MOCA; score < 26) or in the opinion of the evaluating neuropsychologist.
• Individuals unwilling or unable to undergo electrode implantation procedures
• Medical contraindications to neurosurgery or for general anesthesia, neurosurgery, or an MRI scan (required for electrode implantation)
• Neurological disorder other than epilepsy or other significant brain pathology, if contraindicated in the opinion of implanting neurosurgeon.
• Women who are pregnant

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Value-manipulation; Participants with epilepsy will complete a behavioral task in which they use a laptop computer to do a decision-making and memory task.	Behavioral: Value-manipulation; During the decision-making task, different choices are assigned different values probabilistically.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Local-field potentials changes	Detection of local-field potentials (LFPs) in the various regions (hippocampus, amygdala, and frontal cortex). Local field potentials are the biological voltages recorded by macroelectrodes implanted in participant's subcortical regions as part of their treatment for epilepsy. LFP changes (measured as increases or decreases in voltage) as a function of participant behavior will be recorded, and in response to the task manipulation of the value of choices during the decision-making task	During task participation, approx. 30-45 min in the first 2 weeks of hospital stay
Firing rate changes	Single-neuron activity recorded from the hippocampus, amygdala, and frontal cortex. Single-neuron activity refers the micro-scale changes in single-neuron action potentials recorded by microelectrodes implanted in subcortical regions. Firing rate changes (measured as difference in spikes/seconds [Hz]) will be reported for neurons as a function of how behavior changes when the value of choices is altered.	During task participation, approx. 30-45 min in the first 2 weeks of hospital stay

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Reaction time	Reaction times involve measuring how quickly the participant makes each choice during the decision-making and memory tasks, in milliseconds. This will be recorded by logging keypresses and mouse inputs to the behavioral computers. Slow reaction times indicate increased cognitive processing.	During task participation, approx. 30-45 min in the first 2 weeks of hospital stay
Number of hit rates for decision-making	Choices in decision-making task involved logging the decision-making selections that participants make. This will be recorded by logging keypresses and mouse inputs (left or right) to the behavioral computers. This will be used to track whether participants decisions change when value manipulations occur.	During task participation, approx. 30-45 min in the first 2 weeks of hospital stay
Number of hit rates for Memory performance	Memory performance involved logging the memory-recognition selections that participants make. This will be recorded by logging keypresses and mouse inputs (old or new) to the behavioral computers. This will be used to track whether participants memory performance changes when value manipulations occur.	During task participation, approx. 30-45 min in the first 2 weeks of hospital stay

Collaborators and Investigators

• Sponsor: Icahn School of Medicine at Mount Sinai
• Collaborators: National Institute of Mental Health (NIMH)
• Investigators: Principal Investigator: Salman E Qasim, PhD, Icahn School of Medicine at Mt. Sinai

Study record dates

Study Major Dates

• Study Start (Actual): October 31, 2023
• Primary Completion (Estimated): August 1, 2025
• Study Completion (Estimated): August 1, 2025

Study Registration Dates

• First Submitted: October 2, 2023
• First Submitted That Met QC Criteria: October 2, 2023
• First Posted (Actual): October 10, 2023

Study Record Updates

• Last Update Posted (Actual): November 15, 2023
• Last Update Submitted That Met QC Criteria: November 13, 2023
• Last Verified: November 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: GCO 22-1028; K99MH132873 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Access to the raw, de-identified behavioral and neural data will be limited to qualified researchers due to the potential for misuse of participant demographic and neural data within 12 months following article publication. Datasets generated by this project will be made available through the National Institute of Mental Health Data Archive (NDA).
• IPD Sharing Time Frame: Within 12 months following article publication
• IPD Sharing Access Criteria: The datasets will be hosted and available free of charge to approved researchers.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No