Comparison of the Effectiveness of Exposure to Low-LET Helium Particles ((4)He) and Gamma Rays ((137)Cs) on the Disruption of Cognitive Performance.
In this study, the effects of radiation exposure on cognitive performance were evaluated. Rats were exposed to either helium ((4)He) particles (1,000 MeV/n; 0.1-10 cGy; head only) or cesium (137)Cs gamma rays (50-400 cGy; whole body), after which their cognitive performance was evaluated. The results indicated that exposure to doses of (4)He particles as low as 0.1 cGy disrupted performance in a variety of cognitive tasks, including plus-maze performance (baseline anxiety), novel location recognition (spatial performance) and operant responding on an ascending fixed-ratio reinforcement schedule (motivation and responsiveness to changes in environmental contingencies) but not on novel object recognition performance (learning and memory). In contrast, after exposure to (137)Cs gamma rays only plus-maze performance was affected. There were no significant effects on any other task. Because exposure to both types of radiation produce oxidative stress, these results indicate that radiation-produced oxidative stress may be a necessary condition for the radiation-induced disruption of cognitive performance, but it is not a sufficient condition.
a  Department of Psychology, University of Maryland, Baltimore County, Baltimore, Maryland 21250.
Bernard M
BM
Rabin
a  Department of Psychology, University of Maryland, Baltimore County, Baltimore, Maryland 21250.
Kirsty L
KL
Carrihill-Knoll
b  Human Nutrition Research Center on Aging, ARS-USDA, Tufts University, Boston, Massachusetts 02111.
Barbara
B
Shukitt-Hale
D000818:Animals; D002588:Cesium Radioisotopes / Q000009:adverse effects*; D003071:Cognition / Q000528:radiation effects*; D003359:Cosmic Radiation; D005720:Gamma Rays / Q000009:adverse effects*; D006371:Helium / Q000009:adverse effects*; D018499:Linear Energy Transfer; D008297:Male; D018782:Maze Learning / Q000528:radiation effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D002588:Cesium Radioisotopes; D006371:Helium