| dc.description.abstract | The perirhinal cortex is a medial temporal lobe structure situated at a very interesting position in the hierarchy of the brain. It receives projections from all sensory modalities and shows strong connectivity with the entorhinal-hippocampal complex, as demonstrated in rats and monkeys. Its connectivity corroborates its well-established role in object recognition, suggested to be dependent on multisensory integration in the region. The perirhinal cortex is also implicated in functions such as complex perceptual processing and representations of task contingencies and contexts, however. Recently, general combinations of different information into single entities - termed unitization - according to task demands has been suggested to underlie these different perirhinal functions. Supporting such combinations of input is a neuroanatomical connectivity substrate that has not yet been characterized in the mouse model. This substrate may be fruitfully examined experimentally for multisensory integration. Here, the afferent connectivity of the mouse perirhinal cortex is examined with a main focus on sensory inputs. Topographical patterns of innervation onto the region are investigated through retrograde tracing from the rostral and the caudal perirhinal cortex. This is supplemented by examinations of available anterograde tracing data in the Allen Mouse Brain Connectivity Atlas (connectivity.brain-map.org). The current findings suggest extensive sensory convergence in perirhinal cortex from all sensory modalities as well as topographical organization of input along the rostrocaudal and dorsoventral axes of the region. Current findings are largely consistent with the rat literature but do show some notable differences. This study provides an important foundation to inquiries into the anatomical substrate of multisensory integration in the mouse – a model with a wide array of tools for genetic manipulation and access that can allow for future investigations of connectivity with greater resolution. | |