NCT05092100

Neural Mechanisms for Reducing Interference During Episodic Memory Formation

• Status: Enrolling By Invitation
• Phase: N/A
• Study type: Interventional
• Enrollment: 737 (estimated)
• Sponsor: University of Oregon · Academic / Other
• Sex: All
• Age: 18 Years – 80 Years
• Healthy volunteers: Accepted

Summary

Healthy individuals from the University of Oregon and surrounding community will be recruited for participation in behavioral, fMRI and eye tracking experiments that investigate human memory. Recruitment will involve emails, flyers, and local advertisements. Individuals between the ages of 18-80 (or 18-35 for some studies) will be eligible. The broad objective of the research is to understand how humans form distinct memories for similar experiences. Experimental sessions will involve studying and trying to remember various images (e.g., images of natural scenes). The intervention will involve manipulating the similarity and/or learning protocol for the studied images. Outcome measures will include (a) behavioral measures of memory, and/or (b) fMRI measures of hemodynamic activity, and/or (c) eye tracking measures of gaze direction. Experimental sessions will last approximately 1-3 hours.

Detailed description

Objective: The goal of the research studies is to understand how memories are formed for similar experiences such that interference (confusion) between these memories is minimized. Of particular interest is the role of the hippocampus (a brain region important for memory). Participants: Healthy individuals from the University of Oregon and surrounding community will be recruited through fliers, emails, and advertisements. For some of the studies, individuals between 18-80 years of age will be recruited. For others, individuals between 18-35 will be recruited. Design: All studies will involve studying and trying to remember various images (e.g., natural scenes) displayed on a computer screen. Memory decisions will be made and recorded using a computer keyboard or external button box. The similarity of images and/or the specific learning procedures (e.g., number of repetitions, order of study, etc.) will be manipulated. Experimental sessions will be conducted in behavioral testing rooms (with or without eye tracking equipment) and/or in an MRI scanner. Outcomes: Measures of interest will include (a) behavioral responses, (b) fMRI measures of hemodynamic responses, and/or (c) gaze direction as measured by eye tracking equipment. Behavioral responses will consist of simple memory decisions, such as indicating whether or not an image has been seen before or trying to remember associations between images. fMRI data will be analyzed using multivariate pattern similarity analyses. Eye tracking data will be used to measure the specific spatial locations of images that participants fixate on.

Conditions

• Behavior

Interventions

Type	Name	Description
BEHAVIORAL	Visual stimulus similarity	Visual stimulus similarity will be varied in order to test for effects on memory. Learning protocol (the order and frequency with which stimuli are learned) will also be varied.
OTHER	fMRI	fMRI will be used to measure patterns of BOLD activity during learning.
BEHAVIORAL	Eye tracking	Eye tracking will be used to measure patterns of eye movements when viewing images.

Timeline

• Start date: 2021-09-29
• Primary completion: 2025-12-01
• Completion: 2026-01-01
• First posted: 2021-10-25
• Last updated: 2024-09-19

Locations

1 site across 1 country: United States