Explaining speech comprehension: Electrophysiological, evolutionary, and cross-linguistic dimensions

Marslen-Wilson, W. .

Human speech comprehension is a process remarkable for its immediacy and rapidity. The listener interprets an incrementally delivered auditory input, on time scales of around 200-250 msec, in terms of a complex multi-level representation of relevant linguistic knowledge, modulated by the pragmatic context of speaking and more general knowledge of the world. An explanatory neurobiological account of this remarkable set of capacities will have three main components. The first focuses on the real-time flow of neuro-computational activity that underpins the comprehension process. To answer the critical what, when, and where questions about this process requires spatio-temporally resolved data about this neural activity, combined with multivariate analysis techniques. The second seeks to locate language comprehension as an evolutionary, neurobiological process, distinguishing human-unique neurocognitive processes supporting language function from evolutionarily conserved systems and processes that can be traced back to our primate ancestors. Finally, systematic cross-linguistic investigation of the neural systems and processes supporting language comprehension is essential. We need to engage with the immense diversity of human language, and its implications for the neurocognitive mechanisms involved. While the implementation and integration of these three components is far from being achieved in current research, I will discuss recent progress in this direction.