Systematic Psychophysical (Visuallearning)

November 17, 2025 updated by: Takeo Watanabe, Brown University

Systematic Psychophysical Investigation of Visual Learning

The purpose of this study is to investigate how our performance changes after our perceptual system is trained in a certain way ("perceptual learning"). In addition, investigators are interested in identifying and characterizing relationships between such changes and neuroimaging signals recorded from the human brain.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

The long-term goal of the proposed project is to elucidate the underlying mechanisms of visual perceptual learning (VPL) for artificial and natural stimuli, which will be instrumental in developing rehabilitation programs aimed at enhancing damaged or deteriorating vision. The specificity of VPL to the feature and location of the trained visual stimulus is a fundamental characteristic of VPL. To investigate the specificity, one effective way is to use an artificial stimulus such as a Gabor patch as the trained stimulus, as it has been widely used to investigate basic visual processing. Simultaneously, to create an impactful rehabilitation program, the resulting improvements must be generalized to untrained features and locations in visual stimuli encountered in everyday life, including natural scenes (NS). However, it remains uncertain whether the same mechanisms underlie the generalization and specificity in VPL for artificial and NS stimuli. In Specific Aim (SA) 1, investigators aim to examine basic mechanism of the specificity using a Gabor patch. According to a prevailing theory, early visual processing (e.g., 0 to 150ms after the stimulus onset) primarily involves input-level feedforward signals. In contrast, late processing (e.g.,150-300ms after the stimulus onset) involves recurrent processing. To better understand the mechanism of the specificity of VPL it is crucial to clarify whether early or late processing is involved. Additionally, it remains unclear whether the specificity of VPL involves excitation on the trained feature and location or inhibition on untrained features and locations. Therefore, investigators will test Hypothesis 1 (H1): Late processing (H1-a) or early processing (H1-b) plays a role in the specificity of VPL, and H2: Excitatory signals (H2-a) or inhibitory signals (H2-b) are involved in inducing the specificity of VPL. investigators will employ two methods. The backward masking (BM) is used to disrupts and reveal roles of late processing. In preliminary results, BM applied to the trained orientation eliminated the orientation specificity in VPL, supporting H1-a. A Rhythmic Synchronization Orientation Decoding Change (RSDC) method is a novel method that examines at which band(s) of rhythmic synchronization from electroencephalogram (EEG) the decoding performances of trained and untrained features and locations change after VPL training. Preliminary results suggest that trained orientation signals are enhanced at both trained and untrained locations during early processing, while those at untrained locations are inhibited during late processing, leading to the location specificity. In SA2, investigators will examine the specificity and generalizability of VPL for NS. Our first step is to test H3: VPL for the dominant orientation in NS is specific (H3-a) or generalized (H3-b) to other orientations. Preliminary results support H3-b. If true, investigators will further investigate the aspects in NS that induce the generalization of VPL. Preliminary result suggests that higher-order statistics, involving correlations between different orientation and spatial frequency channels derived from NS, play a role in the generalization of VPL for NS. Investigators further aim to test H1 and H2 for NS images, using both the BM and RSDC methods.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
400

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • United States
    • Rhode Island
      • Providence, Rhode Island, United States, 02912
        • Recruiting
        • Brown University
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Ages 18 - 60,
  • Normal or corrected-to-normal vision

Exclusion Criteria:

  • Eye disorders (cataracts, age related macular degeneration, diabetic retinopathy, glaucoma)
  • Drug use (psychoactive drugs, neuroleptic medications, prescription medications that might affect cognitive and motor performance)
  • Sleep disorders (sleep apnea, insomnia)
  • Magnetically or mechanically activated implants (such as cardiac pacemakers)
  • clips on blood vessels in the brain
  • intrauterine devices
  • dentures
  • pregnancy

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: N/A
  • Interventional Model: Parallel Assignment
  • Masking: Single

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Behavioral measure
Time Frame: From enrollment to the end of treatment at 2 weeks.
Changes in rates of correct detection or discrimination in behavioral visual tasks after training are measured.
From enrollment to the end of treatment at 2 weeks.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Brown University

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
National Eye Institute (NEI)

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
July 22, 2025

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 1, 2029

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
January 1, 2029

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
May 2, 2025

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 2, 2025

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
May 11, 2025

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 19, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 17, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
November 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 1203000582-02
  • R01EY019466 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

The types of data to be produced in the current project will be behavioral data and participants' demographic information will also be collected. All data will be de-identified before receipt by the repository. Programs for visual stimuli and data analyses will be produced in the project.

IPD Sharing Supporting Information Type

  • ANALYTIC_CODE

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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