Role of anterior piriform cortex in the acquisition of conditioned flavour preference.
Flavour aversion learning (FAL) and conditioned flavour preference (CFP) facilitate animal survival and play a major role in food selection, but the neurobiological mechanisms involved are not completely understood. Neuroanatomical bases of CFP were examined by using Fos immunohistochemistry to record neuronal activity. Rats were trained over eight alternating one-bottle sessions to acquire a CFP induced by pairing a flavour with saccharin (grape was CS+ in Group 1; cherry in Group 2; in Group 3, grape/cherry in half of animals; Group 4, grape/cherry in water). Animals were offered the grape flavour on the day immediately after the training and their brains were processed for c-Fos. Neurons evidencing Fos-like immunoreactivity were counted in the infralimbic cortex, nucleus accumbens core, and anterior piriform cortex (aPC). Analysis showed a significantly larger number of activated cells after learning in the aPC alone, suggesting that the learning process might have produced a change in this cortical region. Ibotenic lesions in the aPC blocked flavour-taste preference but did not interrupt flavour-toxin FAL by LiCl. These data suggest that aPC cells may be involved in the formation of flavour preferences and that the integrity of this region may be specifically necessary for the acquisition of a CFP.
Department of Psychobiology, Cognitive and Behavioural Neuroscience Programme, and Mind, Brain, and Behaviour Research Centre (CIMCYC), University of Granada, Spain.
Cristina
C
Mediavilla
Department of Experimental Psychology and Mind, Brain, and Behaviour Research Centre (CIMCYC), University of Granada, Spain.
Mar
M
Martin-Signes
Department of Pharmacology, and Centro de Investigación Biomédica (CIBM), University of Granada, Spain.
Severiano
S
Risco
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D002755:Choice Behavior / Q000187:drug effects; D003213:Conditioning, Psychological; D018021:Lithium Chloride / Q000494:pharmacology; D008297:Male; D066195:Piriform Cortex / Q000187:drug effects / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D017208:Rats, Wistar; D013649:Taste / Q000502:physiology*
D016760:Proto-Oncogene Proteins c-fos; D018021:Lithium Chloride