Dominant topographical projections from the ventral nucleus to area EM confirmed physiological reports that it may be considered a primary auditory area (AI).

But how posterior (and other) auditory areas represent acoustic space remains a matter of debate.

Primary visual cortex projects sparsely to A1, whereas higher visual areas innervate auditory areas in a field-specific manner.

The laboratory Norway rat had a larger percentage of dorsolateral cortex devoted to both somatosensory and auditory areas than the wild-caught Norway rat.