Differential effects of ventral and regional dorsal striatal lesions on sucrose drinking and positive and negative contrast in rats

Abstract

The striatum mediates several different components of appetitive ingestive behavior in a region-dependent manner. Previous work has implicated the dorsal and ventral striatum in both consummatory and appetitive aspects of motivated behavior. In this study, we compared the effects of excitotoxic, fiber-sparing lesions of the ventral, medial, and lateral striatum on consummatory responses to sucrose solution rewards. Consummatory responses were measured in terms of volume consumption and licking behavior, and in a successive contrast paradigm. Ventral striatal lesions shifted the intake- concentration function to the left but did not affect positive or negative contrast. Lateral striatal lesions reduced volume consumption, apparently as a result of motoric impairments of licking efficiency, but had no significant motivational effects. The effects of medial striatal lesions were less clear cut, but they probably included both motor and subtle motivational deficits.