Dorsal striatum involvement in response conflict management - A lesion study in rats

Abstract

Action control allows to respond to relevant stimuli while ignoring the non-relevant stimuli in the surrounding environment. In humans this process is generally studied in conflict tasks, such as the Simon task, in which participants respond with a left or right button press to the non-spatial relevant feature (e.g. the color) of a lateralized stimulus, while ignoring the stimulus position. In this study we used a visual version of the Simon task that we have previsously developed in rats to investigate the involvement of the dorsal striatum, a brain area that is central in action control processes. We tested the effect of excitotoxic lesions of the dorsomedial (DMS) and dorsolateral (DLS) areas in learning to control response interference. We showed that both DMS and DLS lesions negatively impacted rat performances, and this effect strongly depends on task practice. These results suggest an involvement of both areas in learning to manage response conflict.