Abstract
The aim of this study is to explore the role of the superior colliculus (SC) in the generation and maintenance of the rat head direction (HD) cell signal. The SC is a major pathway by which visuospatial information enters the limbic system and it contains indirect connections to the anterior dorsal nucleus of the thalamus (ADN), where HD cells are found. To determine the functional relationship between these areas, reversible inactivations of the SC were performed while HD cells were recorded in the ADN. This study found that inactivations of the SC produced a degradation of the spatial signal within the HD system, as evidenced by unstable directional-specific activity relative to the landmarks within recording sessions. This study is the first to report that the rat SC is involved in the integrity of the ADN HD signal.