Brief exposures to theta-burst magnetic fields impair the consolidation of food-induced conditioned place preference.
Theta-burst magnetic fields (1 microT) designed to mimic electrical stimuli employed in vitro to affect long-term potentiation have been previously shown to impair the acquisition of conditioned fear. In the current study, the authors were interested in investigating whether similar magnetic fields could affect the consolidation of food-induced conditioned place preference. Fourteen male Wistar rats were exposed to a theta-burst magnetic field (1 s pulse of 5 trains of an LTP-evoking pattern) continuously or with either a 5 s or 10 s interstimulus interval for 15 min immediately following 6 daily conditioning trials (15 min/day) in a place preference apparatus. Testing demonstrated the durations in the food-paired chamber was significantly shorter for all of the magnetic field-exposed groups compared to the sham-exposed group (they remained for longer periods in the food-paired chamber, typical of normal rats). In addition, the group exposed continuously to the LTP-magnetic field (1-ms interstimulus duration) displayed the least time in the food-paired chamber. The treatments explained 80% of the variance in durations within the experimental setting. These results suggest that exposures to theta-burst magnetic fields elicit amnesic effects for contextual stimuli.
Delparte
J J
JJ
Behavioral Neuroscience Laboratory, Laurentian University, Sudbury, Ontario, Canada.
Persinger
M A
MA
D000818:Animals; D001522:Behavior, Animal / Q000528:radiation effects; D003216:Conditioning, Operant / Q000502:physiology / Q000528:radiation effects*; D004574:Electromagnetic Fields / Q000009:adverse effects*; D055590:Electromagnetic Phenomena / Q000379:methods; D005502:Food; D007859:Learning Disabilities / Q000209:etiology* / Q000503:physiopathology; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors