An Investigation of Attentional and Inhibitory Processes During Active Visual Search in Humans

Not Applicable

Not yet recruiting

• Conditions: Eye Movements; Attention; Executive Function
• Interventions: Other: Visual tasks

• Registration Number: NCT06587113
• Lead Sponsor: University of Colorado, Denver

Brief Summary

The goal of this study is to investigate the finding that there are large individual differences in how participants move their eyes during active visual search. For example, some individuals tend to fixate, that is point their eyes steadily at a single location, for longer than other individuals before moving to another location. This experiment will use behavioral tasks to measure an individual's attentional and inhibitory functioning, and then see how each of these contributes to between-participant variability in eye movement behavior during visual search.

Detailed Description

To accomplish the goal of understanding the source of individual variability in eye movement patterns, each participant will complete three separate tasks. The first task will require participants to find a target and eye movements will be measured to assess individual differences in fixation duration and other types of eye movement behavior. A second task will evaluate attentional functioning over the visual field by requiring participants to detect briefly-presented targets using their peripheral vision. Finally, a third task will assess inhibitory functioning by having participants attempt to stop eye movements after they have been programmed.

Basic Information
|
Recruitment & Eligibility
|
Study & Design
|
Trial Locations

Study Timeline

• Status Verified: 2024-09
• Study First Submitted: 2024-09-04
• Study First Submitted QC: 2024-09-04
• Last Update Submitted: 2024-09-04
• Study First Posted: 2024-09-09
• Last Update Posted: 2024-09-09
• Study Start: 2024-09-15
• Primary Completion: 2025-05
• Study Completion: 2025-05

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 75

Inclusion Criteria

• 18-65 years old

Read More

Exclusion Criteria

• Self-reported history of neurological illness
• Uncorrected vision problems

Read More

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Study Group	Visual tasks	This study examines eye movement behavior using eye-tracking technology. Healthy participants perform three different tasks, including a visual search task, a stop-signal task, and a useful field of view task. Behavioral performance and eye movements are recorded for all tasks.

Primary Outcome Measures

Name	Time	Method
First fixation duration during visual search	During visual search task	This measure is the average first fixation duration during the visual search task. Possible scores are a minimum of 50 ms with an undeterminable positive number of ms as a maximum. This measure indicates the duration of processing before the first eye movement decision.
Fixation count during visual search	During visual search task	This measure is the count the average number of eye movements participants made per trial during the visual search task. Possible scores range from a minimum of 0 to approximately 40 eye movements, given the time available. This measure indicates the amount of active exploration of the display during search.
Stop signal reaction time	During inhibitory task	Stop signal reaction time is a quantitative estimate of how long participants take to successfully inhibit a planned eye movement. Possible scores range from a minimum of 0 ms to a maximum of about 600 ms. Low scores indicate strong inhibitory ability and high scores indicate weak inhibitory ability.
Useful field of view thresholding	During attention task	Performance in a thresholding task indicates participants ability to detect a briefly presented target among distractors with 80% accuracy. Contrast of the displays varies until performance meets achieved level. Possible scores range from 0 to 100% contrast. Lower contrast indicates better information accrual, while higher contrast indicates worse.
Useful field of view dual task performance	During attention task	Performance in a dual task indicates participants ability to spread attention across the visual field. Possible scores range from 0 to 100% accuracy. Higher performance indicates better information accrual, while lower performance indicates worse.

Secondary Outcome Measures

Name	Time	Method
Average fixation duration during visual search	During the visual search task	This measure is the average fixation duration across all fixations in a trial during the visual search task. Possible scores range from a minimum of 50 ms to approximately 500 ms. This measure indicates the average duration of processing before a saccadic decision is made.

Trial Locations

Locations (1)

University of Colorado Denver; 🇺🇸 Denver, Colorado, United States