Experiment 3: Mixed vs Blocked; Dashboard Paradigm

NCT06934213 | Recruiting

• 1 other identifier: 2007P000646-J
• Study Type: interventional
• Target: 50
• Locations: 1 country
• Sites: 1

Brief Summary

The goal is to look for qualitative differences in visual search behavior when one search is performed many times in a row compared to when multiple search tasks are intermixed. Four search tasks are tested. The target is the same in every task but the types of distractors change from task to task. In this version, observers get some degree of choice in what they are searching.

Conditions

Vision; Healthy; Attention

Keywords

visual search; visual attention

Outcome Measures

Primary Outcomes (1)

• Response Time (RT)

  How long it takes to respond that the target is present or absent.

  through study completion, an average of one year

Secondary Outcomes (1)

• Accuracy

  through study completion, an average of one year

Study Arms (5)

Trial Choice condition

EXPERIMENTAL

In this condition, participants are allowed to choose which task to perform on each trial. At the beginning of each trial, the message "Choose your task" appears in the center of the screen. Participants choose one of four tasks by clicking on the corresponding button on the left side of the patch. The button is deactivated when the number of trials completed in a task reached 50. If a deactivated button is clicked, the message "Choose another task" appears at the center again.

Behavioral: Choice; Behavioral: Mixed trials

Block Choice condition

EXPERIMENTAL

In this condition, participants begin by choosing one of the four tasks. Participants do not need to choose a task before each trial; the current trial is drawn automatically from the most recently chosen task until the participant actively chooses to switch tasks or until the full complement of trials for that task is exhausted. At the start of each trial, a "switch" button appears at the center of the display for 700 msec. If participants click on that button within the 700 msec, they are prompted to select the task. If participants does not click the switch button within the 700 msec window, the button vanished and a trial from the current task will be presented. When the number of trials of one task reaches its limit, participants are asked to select another task.

Behavioral: Choice; Behavioral: Mixed trials

Random condition

EXPERIMENTAL

In this condition, participants do not choose which task to perform on each trial. The order of the trials is randomized and assigned to the participant before each trial. Before each trial, the target task is highlighted and activated, while the other buttons remain deactivated. The trial begins only when the participant clicks on the correct task button.

Behavioral: Choice; Behavioral: Mixed trials

Blocked condition

EXPERIMENTAL

In this condition, participants also have no choice. Here, trials of each task type are presented in a blocked fashion. After 50 trials of one type, the task is changed to another task. To keep the motor demands similar to the choice conditions, at the beginning of each trial, participants need to click the highlighted button for the assigned task type. The order of blocks is counterbalanced across participants.

Behavioral: Choice; Behavioral: Mixed trials

Yoked condition

EXPERIMENTAL

Participants in this condition see trials in the order chosen by a participant in the Trial Choice condition. Again, to keep the motor demands similar to the choice conditions, at the beginning of each trial, participants need to click the highlighted task button for the assigned task type though they have no choice in the matter.

Behavioral: Choice; Behavioral: Mixed trials

Interventions

Choice BEHAVIORAL

The observer gets to make a choice about the sequence of trials they see

Block Choice condition; Blocked condition; Random condition; Trial Choice condition; Yoked condition

Mixed trials BEHAVIORAL

The search tasks are either intermixed. Otherwise trials are run in blocks

Block Choice condition; Blocked condition; Random condition; Trial Choice condition; Yoked condition

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Pass Ishihara color vision test

You may not qualify if:

• vision less than 20/25 with correction
• \- history of neuromuscular or visual disorders

Sponsors & Collaborators

• Brigham and Women's Hospital: lead
• National Eye Institute (NEI): collaborator

Study Sites (1)

Brigham & Women's Hospital

Boston, Massachusetts, 02115, United States

RECRUITING

Study Officials

• Jeremy M Wolfe, PhD

  Brigham and Women's Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Jeremy M Wolfe, PHD

CONTACT

6178511166; jwolfe@bwh.harvard.edu

Cailey Tennyson, PhD

CONTACT

617-525-3681; ctennyson1@bwh.harvard.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: There are five conditions. Each condition is a different group of observers.

Study Record Dates

• First Submitted: April 11, 2025
• First Posted: April 18, 2025
• Study Start: June 1, 2024
• Primary Completion (Estimated): June 1, 2029
• Study Completion (Estimated): June 30, 2029
• Last Updated: April 21, 2025

Record last verified: 2025-04

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF
• Time Frame: Data will be placed on the Open Science Framework (OSF) site and should be permanent
• Access Criteria: open

Locations

US (1)