Neural Mechanisms for Reducing Interference During Episodic Memory Formation

NCT ID: NCT05092100

Last Updated: 2024-09-19

Basic Information

• Recruitment Status: ENROLLING_BY_INVITATION
• Clinical Phase: NA
• Total Enrollment: 737 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2021-09-29
• Study Completion Date: 2026-01-31

Brief 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

Study Design

• Allocation Method: NON_RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Behavioral

This arm will use behavioral procedures to test memory for different visual stimulus conditions.

Group Type: EXPERIMENTAL

Visual stimulus similarity

Intervention Type: BEHAVIORAL

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.

fMRI pattern similarity

This arm will use fMRI and behavioral methods to test memory for different visual stimulus conditions.

Group Type: EXPERIMENTAL

Visual stimulus similarity

Intervention Type: BEHAVIORAL

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.

fMRI

Intervention Type: OTHER

fMRI will be used to measure patterns of BOLD activity during learning.

eye tracking

This arm will use eye tracking and behavioral methods to test memory for different visual stimulus conditions.

Group Type: EXPERIMENTAL

Visual stimulus similarity

Intervention Type: BEHAVIORAL

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.

Eye tracking

Intervention Type: BEHAVIORAL

Eye tracking will be used to measure patterns of eye movements when viewing images.

Interventions

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.

Intervention Type: BEHAVIORAL

fMRI

fMRI will be used to measure patterns of BOLD activity during learning.

Intervention Type: OTHER

Eye tracking

Eye tracking will be used to measure patterns of eye movements when viewing images.

Intervention Type: BEHAVIORAL

Other Intervention Names

Learning protocol

Eligibility Criteria

Inclusion Criteria

Participants in behavioral studies must be:

• healthy and between the ages of 18-35 years old
• native English speakers
• right-handed.

Participants in fMRI studies must be:

• healthy and between the ages of 18-80 years old
• native English speakers
• right-handed.

Exclusion Criteria

For behavioral studies:

• Potential participants will be informed that use of psychoactive drugs, mental health disorders, and chronic or temporary sleep deficits (an average of less than 6 hours of sleep over the past month or less than 4 hours of sleep the night prior to the experimental session) are reasons for exclusion because of the potential influence on cognitive functioning.

For fMRI studies:

• For some sub-studies, individuals older than age 35 will be excluded because of potential differences in cognitive and brain function across age groups that are beyond the scope of the proposed studies.
• Individuals will be informed that use of psychoactive drugs, mental health disorders, and chronic or temporary sleep deficits (an average of less than 6 hours of sleep over the past month or less than 4 hours of sleep the night prior to the experimental session) are reasons for exclusion because of the potential influence on cognitive functioning.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 80 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

University of Oregon

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Brice A Kuhl, Ph.D.

Role: PRINCIPAL_INVESTIGATOR

University of Oregon

Locations

University of Oregon

Eugene, Oregon, United States

Countries

United States

Other Identifiers

06302015.045

Identifier Type: -

Identifier Source: org_study_id