In the past fifteen years there has been considerable interest in neural circuits that initiate behavior patterns. For many types of behaviors, this involves decision-making circuits whose primary elements are neither purely sensory nor motor, but represent a higher order of neural pro cessing. Of the large number of studies on such systems, analyses of startle circuits compose a major portion, and have been carried out on systems found throughout the animal kingdom. Startle has been an im portant model because of the reliability of the behavioral act for laboratory study and the...

In the past fifteen years there has been considerable interest in neural circuits that initiate behavior patterns. For many types of behaviors, this involves decision-making circuits whose primary elements are neither purely sensory nor motor, but represent a higher order of neural pro- cessing. Of the large number of studies on such systems, analyses of startle circuits compose a major portion, and have been carried out on systems found throughout the animal kingdom. Startle has been an im- portant model because of the reliability of the behavioral act for laboratory study and the...