Striatal organization of feeding behavior in the decorticate rat

Abstract

Varying degrees of decortication were performed on rats in order to determine the level at which feeding behavior would first appear. The largest lesion left the hypothalamus and thalamus intact, with all structures rostral, lateral, and dorsal removed. These animals remained permanently aphagic throughout long survival times and were extremely hyperactive. Their hyperactivity could be attributed to released diencephalic appetitive mechanisms. When portions of the posterior region of the corpus striatum were added to the above preparation, feeding behavior appeared and increased in complexity as more tissue remained intact. Hyperactivity was markedly attenuated in these animals. Thus, there is a close correlation in the decorticate rat between the appearance of complex behaviors, such as feeding, and of caudate inhibition of the excitatory mechanisms of the diencephalon.