Effects of aversive stimuli on learning and memory in Arctic ground squirrels.
The present study was designed to assess effects of aversive stimuli on learning and memory in wild-caught Arctic ground squirrels (AGS, Spermophilus parryii) using an active avoidance learning paradigm. Results indicate that animals trained with low-value aversive stimuli (air puffs and lights) retained the task better than animals trained with high-value aversive stimuli (air puffs, lights, and foot shock). Poor retention could not be explained by learning impairment, fear-induced freezing behavior or the effects of massed versus spaced training trials. Wild-caught AGS readily hibernate under laboratory conditions and provide a model of pronounced adult synaptic plasticity associated with emergence from hibernation. Characterization of learning and retention using active avoidance as well as other learning paradigms is a first step towards developing behavioral paradigms to assess cognitive function in this wild-trapped species. The present study shows that captive AGS are sensitive to aversive stimuli, argues for a direct effect on retention and suggests that high baseline levels of stress in a captive population may influence behavioral measures. The results further suggest that future studies of the effects of hibernation on learning and retention of active avoidance tasks employ low-level aversive stimuli.
Zhao
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H
Alaskan Basic Neuroscience Program, Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, AK 99775, USA. fthz@uaf.edu
Bucci
D J
DJ
Weltzin
M
M
Drew
K L
KL
D000818:Animals; D001110:Arctic Regions; D001348:Aversive Therapy; D001362:Avoidance Learning / Q000502:physiology*; D001522:Behavior, Animal; D004193:Discrimination Learning / Q000502:physiology; D005260:Female; D006605:Hibernation / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D010812:Physical Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D012153:Retention, Psychology / Q000502:physiology*; D012589:Sciuridae