Behavioral measurement of laser flashblindness in rhesus monkeys.
Flashblindness was measured in rhesus monkeys performing a visual detection task. Stimulus field subtense was 3.5 degrees, and mean luminance was 10 cd.m-2. Single-pulse laser exposures (doubled Nd:glass, 530-nm wavelength, 20-ns pulsewidth) were presented in Maxwellian-view and formed a 12.5 degrees diameter spot centered on the fovea. The independent variables were: test grating contrast (10% and maximum contrast); test grating spatial frequency (1, 4, 12 c.deg-1); and averaged laser exposure energy (1-94% retinal maximum permissible exposure). The dependent variable was flashblindness, operationally defined as the time between a laser exposure and the first response in a pair of consecutive correct responses (referred to as "time to criterion"). Time to criterion decreased as the contrast of the grating increased. The longest times to criterion were at a spatial frequency of 12 c.deg-1, next longest at 1 c.deg-1, and shortest at 4 c.deg-1. Both the mean and S.E.M. of times to criterion increased with the laser exposure energy.
Rhodes
J W
JW
Technology Services Division, KRUG International, San Antonio, TX 78279-0644.
Garcia
P V
PV
Cosgrove
D J
DJ
D000818:Animals; D001522:Behavior, Animal / Q000528:radiation effects*; D001766:Blindness / Q000209:etiology*; D007834:Lasers; D008253:Macaca mulatta; D008452:Maximum Allowable Concentration; D010775:Photic Stimulation / Q000295:instrumentation; D013997:Time Factors