Persistence of the pattern of feeding in chicks with hyperstriatal lesions

Chicks with dorsal midline hyperstriatal lesions (DMHA) were trained to prefer red to yellow food before being presented with a choice from a plain floor (experiment 1) or a pebble-encrusted floor (experiment 2). On both tests DMHAs showed a relatively stable pattern of choice compared to controls. In experiment 1, controls decreased their intake of non-preferred yellow food on day 1, but this sharply increased on subsequent tests. In experiment 2, controls increased the number of pebbles pecked, and thus, the length of a run of pecks on non-preferred food changed with respect to DMHAs. Chicks with more lateral lesions gave patterns distinct from controls and DMHAs showing an initial disruption of the trained preference. The choice of chicks with more ventral or posterior lesions could not be distinguished from controls. The lack of lability of the trained feeding behavior of DMHA-lesioned chicks is interpreted as consistent with the suggestion that the DMHA may have functions which are similar to the "hippocampus" of mammals.