Prerequisites for an evolutionary stance on the neurobiology of language

The neurobiology of language has to specify the cognitive architecture of complex language functions such as speaking and comprehending language, and, in addition, how these functions are mapped onto the underlying anatomical and physiological building blocks of the brain (the neural architecture). Here it is argued that the constraints provided by the classical anatomical measures (cytoarchitectonics and myeloarchitectonics) are in our current understanding only very loose constraints for detailed specifications of cognitive functions, including language learning and language processing. However, measures of the computational features of brain tissue might provide stronger constraints. For understanding cognitive specialization, for the time being we thus have to put our cards on measures of functional instead of structural neuroanatomy. The implication for an evolutionary stance on the neurobiology of language is that in a cross-species comparative perspective one needs to identify the factors that gave rise to the properties of the canonical microcircuits in the neocortex, and to the large scale network organization that created the language-readiness of the human brain.