The Dynamics of Representational Change Underlying Recall

Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18-40
SponsorBrown University

About this trial

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.

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

None

Disqualifiers

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

Trial design

Design model

Single group

Treatments tested in this trial

  • 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.

Treatment groups

30 Participants
are divided into 1 treatment group
Group A: Experimental Memory Retrieval TaskExperimental treatment 1 intervention

Trial outcomes

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.

Time frame
1 hour

Secondary outcomes

Other outcomes

Sponsors and contacts

Click on the lead sponsor to view all of their trials.

Brown University

Lead sponsor

National Institute of General Medical Sciences (NIGMS)

Collaborator