Adaptation to Visual Tracking With a Central Simulated Scotoma
Abstract
Lasers on the battlefield could produce retinal injury that results in a blind spot (scotoma) in a person's central vision. The effect of a central 3 degree artificial scotoma on tracking and shooting with 3 different levels of target path difficulty and the effect of practice on the ability to track with a scotoma are reported. A three-degree artificial scotoma was produced using an SRI dual-Purkinje-image eyetracker. Subjects monocularly tracked a 6 minute of arc target with a joystick controlled cross hair. Eighteen subjects, 6 for each target path difficulty level, made 20, 1 minute tracking runs per day for 7 days. RMS error for the eye to target distance, cross hair to target distance, and the cross hair to target distance when shooting were determined. Eye position was monitored throughout the trial to determine tracking strategy. Three-degree scotomas decreased tracking and aiming performance dramatically for all three target path difficulty levels. The effect of a scotoma was greatest on the first trials when they were introduced and there was improvement with practice. All subjects learned to keep the scotoma away from the target and cross hair so that they would not be hidden by the scotoma. This strategy improved their performance. However, no subjects improved to their level of performance without a scotoma. These results further substantiate previous results indicating that scotomas may have significant impact on the completion of operational missions. Practice and exposure to a simulated scotoma may lessen but not eliminate the decrease in performance resulting from a central scotoma.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2002
- Accession Number
- ADA405068
Entities
People
- Leon N. Mclin Jr.