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

Summary

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.

Detailed Description

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.

Eligibility Criteria