Extended lowered body temperature increases the effective CS-US interval in conditioned taste aversion for adult rats.
Assuming body temperature correlates with metabolic activities, rate of body temperature recovery was manipulated to assess effects on long-trace conditioning in a conditioned taste-aversion paradigm. Following 10 min. access to a .1% saccharin solution and then 10 min. immersion in 0-0.5 degrees C water, two groups of 16 Wistar-derived, 81-113 day-old, male albino rats received either saline or lithium chloride injections 3 hr. later. These two groups were subdivided on basis of warming rate during the 3-hr. interval. Half of the rats recovered at room temperature (20 degrees to 21 degrees C), and half recovered in an incubator maintained at 30 degrees C. Maintaining a lowered body temperature between the conditioned stimulus and unconditioned stimulus allowed an association to be made at 3 hr., an interval that normally does not support conditioning. In contrast, lowering body temperature and then inducing a fast warming rate did not produce evidence of an aversion. It is suggested that maintaining a low body temperature over the interval between the presentation of the conditioned stimulus and unconditioned stimulus slows a metabolic clock that extends the measured interval at which associations can be made using conditioned taste-aversion procedures.
Hinderliter
Charles F
CF
Department of Psychology, University of Pittsburgh at Johnstown, PA 15904, USA. cfh5@pitt.edu
Goodhart
Mark
M
Anderson
Matthew J
MJ
Misanin
James R
JR
D000818:Animals; D001362:Avoidance Learning; D001522:Behavior, Animal; D003214:Conditioning, Classical; D007036:Hypothermia, Induced; D008297:Male; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013649:Taste; D013997:Time Factors