Accession Number : ADA319033

Title :   Smooth Eye Movement Response to Complex Motion Sequences.

Descriptive Note : Final technical rept. Jun 91-Jun 95,

Corporate Author : HUGHES TRAINING INC MESA AZ TRAINING OPERATIONS DIV

Personal Author(s) : Lindholm, Julie M. ; Wetzel, Paul A. ; Askins, Timothy M.

PDF Url : ADA319033

Report Date : SEP 1996

Pagination or Media Count : 39

Abstract : To examine the spatiotemporal properties of the motion sensors for the smooth pursuit system, we presented horizontal motion sequences in which successive target displacements were in accord with a composite waveform representing the sum of a constant velocity ramp and a sawtooth. The sequences differed in global velocity (GV = ramp velocity = 0 or 4 deg/sec), local velocity (LV = ramp velocity + sawtooth velocity = -8 or -4 deg/sec, for GV =0, and -8, -4,0, 8, 12 deg/sec, for GV = 4), and local-segment duration (12 values between 67 and 700 msec). When the duration of a local-velocity segment was relatively short C less than or equal to 133 msec, for GV =4 deg/sec; less than or equal to 200 msec, For GY =0 deg/sec), mean pursuit velocity matched the GV. As the segment duration increased, mean pursuit velocity shifted gradually toward the LV. Changes in cumulative saccadic amplitude mirrored the changes in smooth pursuit velocity. The spatiotemporal-frequency spectra of the motion sequences suggested that the pursuit system responded in accord with the drift velocities of very low spatial frequencies. The spectra of the space-time retinal images suggested that pursuit was maintained not by the absence of retinal image motion but by the presence of appreciable spectral energy for components with a drift velocity of approximately zero.

Descriptors :   *OPTICAL TRACKING, *EYE MOVEMENTS, AIR FORCE RESEARCH, OPTICAL TARGET DESIGNATORS, PERFORMANCE(HUMAN), WAVEFORMS, OPTICAL IMAGES, RETINA, VISUAL PERCEPTION, SPECTRAL ENERGY DISTRIBUTION, FLIGHT SIMULATORS, PURSUIT COURSES, PROJECTILE TRAJECTORIES, BUFFER STORAGE, VISUAL TARGETS, DIGITAL TO ANALOG CONVERTERS, FOVEA, VISUAL ACUITY, IMAGE MOTION COMPENSATION, SAWTOOTH WAVEFORMS, CUES(STIMULI).

Subject Categories : Anatomy and Physiology
      Optical Detection and Detectors

Distribution Statement : APPROVED FOR PUBLIC RELEASE