Abstract: | In 5 experiments, 110 normal male Long-Evans hooded rats and 125 Ss with lesions of the gustatory neocortex (GN) were compared for their ability to learn aversions to taste cues paired with toxicosis. When the taste presentation was followed immediately by toxicosis, normal Ss and 8 Ss with lesions of the posterior (visual) neocortex learned aversions to sucrose, sodium chloride, quinine hydrochloride, and hydrochloric acid solutions. Ss with GN lesions learned aversions to all solutions except sucrose. In preference tests, all solutions were shown to be discriminable from water by both normal and GN-lesioned Ss. Under conditions in which a 6-hr delay separated taste presentation and toxicosis, normals again learned specific aversions to all 4 solutions, but Ss with GN lesions failed to learn specific aversions to sucrose, sodium chloride, and hydrochloric acid solutions. It was shown that the ability of Ss with GN lesions to learn aversions to sucrose and quinine depended on stimulus concentration. It is proposed that the data can be accounted for by postulating a change in the threshold for taste illness associations following GN lesions. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |