State Dependent Responses

Abstract

One of the oldest problems in ethology is the study of the mechanisms underlying behavioral states (that is, periods of time commonly lasting many seconds rather than milliseconds) in which particular responses or groups of responses are likely to be performed and other behavior is less likely or entirely inhibited. For Neuroethology the greatest interest must lie in the role played in such states by persisting patterns of activation of neural structures. Robert Hunsperger reminds us of the great effect produced in behavioral science by the demonstration by Hess that normally organized sequences of species-specific responses could be evoked in cats by stimulation of the brainstem. The detailed organization of the neural systems involved in a particular behavioral state, such as defense studied by Hess, is now much better understood, as is exemplified during the Study Institute by Uwe Jürgens’ description of the neural basis for vocalization in the squirrel monkey.