Visual Attention, Object Recognition, and Eye Movements in Healthy Volunteers

N/ANot Yet RecruitingNCT07756853

National Eye Institute (NEI)40 enrolled

Overview

Background: Vision is vital for many of our daily activities. Researchers want to learn more about how we aim our eyes (that is, what images, such as faces, immediately attract our attention) and how we direct our attention (that is, what we see and what we ignore). Objective: To study how healthy adults process and respond to visual images. Eligibility: Healthy people aged 18 years with no vision problems. Design: Participants will have 5 to 10 clinic visits over 2 to 4 months. Some participants may have up to 25 visits. Each visit lasts about 1 hour. Participants will be screened. They will answer questions about their medical and eye history. They will have a standard eye exam; eye drops will be used to dilate the pupils. (They may skip this exam if they have had an eye exam at the NIH within the past year.) Participants will perform eye movement tests. They will sit in front of a computer and view images that appear on the screen. They may be asked to respond to what they see by speaking, moving their hands, looking in a certain direction, or pushing a button. Their eye movements will be tracked. For some tests, participants heads may be held steady using a chinrest and head strap. For some tests, they may wear a cap fitted with cameras that use invisible lights in front of their eyes.

Study Description: This study will determine how our vision is automatically drawn toward certain types of visual stimuli, such as faces and other socially relevant stimuli. We hypothesize that this tendency is driven by simple and basic visual features that are processed at very short latencies, rather than by complex and elaborate visual processing. We will test this hypothesis by asking subjects to perform simple behavioral tasks-pressing buttons on a button box or directing their gaze - while looking at visual images presented on a computer screen. Objectives: Primary Objective: To determine how visual information about socially relevant visual stimuli alters the timing and kinematics of saccadic eye movements. Secondary Objective: To determine how visual information about socially relevant stimuli alters the allocation of visual selective attention. Endpoints: Primary Endpoint: Measurement of significant deviations in the trajectories or latencies of saccadic eye movements that are specific to basic features of socially relevant visual stimuli. Secondary Endpoint: Measurement of significant changes in the performance of visual attention tasks that depend on basic features of socially relevant visual stimuli.

Study Type

OBSERVATIONAL

Eligibility

Sex: ALLMin age: 18 YearsMax age: 100 Years

Medical Language ↔ Plain English

* INCLUSION CRITERIA: In order to be eligible to participate in this study, an individual must meet all of the following criteria: * Stated willingness to comply with all study procedures and actively pay attention to visual stimuli and respond as appropriate. * Participant has visual acuity of 20/25 or better in both eyes. * Participant must be 18 years old or older. * Participant must understand and be willing to sign a written informed consent document. EXCLUSION CRITERIA: An individual who meets any of the following criteria will be excluded from participation in this study: * Participant has an ocular, visual, or oculomotor problem that in the opinion of the Principal Investigator (PI) and/or clinical associate investigator would interfere with the participant s normal eye movements, visual perception, or required tasks. * Participant has a history of eye patching (amblyopia or lazy eye). * Participant has a non-ocular condition (e.g., neuropsychological conditions) that in the opinion of the PI and/or clinical associate investigator would interfere with the participant s normal eye movements or visual perception.

Outcomes

Primary Outcomes

Measurement of significant deviations in the trajectories or latencies of saccadic eye movements that are specific to basic features of socially relevant visual stimuli.

By measuring the trajectory of eye movements made in the presence of socially relevant visual stimuli (e.g., faces) versus similar visual stimuli that are not socially relevant (e.g., houses), we will test how socially relevant stimuli can impact visual processes that are automatic and occur at very short latencies. Depending on the size of these eye movement measurement effects, we will obtain a sufficient number of observations per subject for each condition, and/or obtain observations from 10-30 subjects to verify the robustness and replicability of the outcomes.

Time frame: ongoing

Secondary Outcomes

Measurement of significant changes in the performance of visual attention tasks that depend on basic features of socially relevant visual stimuli.

By tallying the answers and response times of participants as they make visual judgments in the presence of socially relevant visual stimuli (e.g., faces) versus similar visual stimuli that are not socially relevant (e.g., houses), we will test how socially relevant stimuli can impact higher-order visual processing such as visual attention, perception, and decision making.