The Dynamics of Representational Change Underlying Recall

NCT07442266 | Recruiting

• 2 other identifiers: STUDY000008495P30GM149405
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to examine how repeated memory retrieval changes visual representations in the brain in healthy adult participants. Specifically, the study aims to determine whether repeated recall strengthens or transforms neural representations in visual cortex compared to a time-matched control condition. The main questions it aims to answer are: 1) Does repeated retrieval produce cumulative changes in visual cortical representations compared to a control condition matched for elapsed time? 2) Do these representational changes differ for simple spatial stimuli and complex natural images? Researchers will compare neural activity patterns during repeated retrieval to those during a control retrieval condition to determine whether repeated recall leads to systematic changes in representational structure beyond those attributable to the passage of time. Participants will: 1) complete two fMRI sessions. 2) Undergo a localizer session including anatomical imaging, population receptive field (pRF) mapping, and a visual category localizer task. 3) Study cue-stimulus pairs consisting of either simple spatial patterns or natural images. 4) Recall previously studied stimuli multiple times during repeated and control retrieval conditions while undergoing fMRI scanning. Brain activity patterns during study and recall will be compared to assess how repeated retrieval influences the structure and tuning of visual representations.

Conditions

Episodic Memory

Outcome Measures

Primary Outcomes (1)

• Representational Change in Visual Cortex

  Difference in multivoxel BOLD activity patterns in visual cortex between repeated and control retrieval conditions during fMRI.

  1 hour

Study Arms (1)

Experimental Memory Retrieval Task

EXPERIMENTAL

All participants will complete a visual memory encoding and retrieval task during fMRI scanning. The study uses a within-subject design in which each participant completes both a repeated retrieval condition and a time-matched control retrieval condition. This design allows comparison of neural representational changes associated with repeated retrieval while controlling for elapsed time.

Behavioral: Visual Memory Encoding and Retrieval Task During fMRI

Interventions

Visual Memory Encoding and Retrieval Task During fMRI BEHAVIORAL

Participants will study cue-stimulus associations and subsequently retrieve the associated stimuli while undergoing fMRI scanning. Retrieval will occur under two conditions: (1) repeated retrieval, in which stimuli are recalled five times, and (2) control retrieval, in which stimuli are recalled twice with timing matched to the repeated condition. Neural activity patterns during study and recall will be measured using BOLD fMRI.

Experimental Memory Retrieval Task

Eligibility Criteria

• Age: 18 Years - 40 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may not qualify if:

• Under the age of 18 or over the age of 40
• Does not live in the United States or is not a native speaker of English
• Diagnosis of a neurological disorders, a history of head trauma, or diagnosis of psychiatric disorder
• Imperfect and uncorrected visual acuity, color blindness, or imperfect hearing
• Magnetically or mechanically activated implants or other untested metal implants
• Claustrophobia

Sponsors & Collaborators

• Brown University: lead
• National Institute of General Medical Sciences (NIGMS): collaborator

Study Sites (1)

Brown University Magnetic MRI Research Facility

Providence, Rhode Island, 02906, United States

RECRUITING

Central Study Contacts

Serra E Favila, PhD

CONTACT

(401) 863-3486; serra_favila@brown.edu

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

Model Details: Within-subject experimental design in which all participants complete all conditions during fMRI.

Study Record Dates

• First Submitted: February 24, 2026
• First Posted: March 2, 2026
• Study Start: February 3, 2026
• Primary Completion: August 1, 2026
• Study Completion: August 1, 2026
• Last Updated: March 2, 2026

Record last verified: 2026-02

Locations

US (1)