Dr Max Garagnani:

Modelling language in action: simulating the emergence and dynamics of action-perception circuits in a neuroanatomically grounded model of fronto-temporal cortical areas

Abstract

I will briefly present a neural-network model that we developed to simulate and explain, at cortical level, word learning and language comprehension processes as they are believed to occur in motor and sensory primary, secondary and higher association areas of the (left) frontal and temporal lobes of the human brain. The model was built to closely reflect well-documented connectivity and neurobiological features of the corresponding cortices, including correlational synaptic-plasticity mechanisms for learning.

I will then describe how this model can (1) simulate the spontaneous emergence of memory traces for words as distributed, strongly connected action-perception neural circuits (Hebbian “cell assemblies”) whose behaviour well accounts for neurophysiological responses to familiar words and unknown lexical items, and (2) mechanistically explain why the cortical processes underlying the spontaneous formation of an intention to speak preferentially originate from association / multimodal (and not primary motor) prefrontal and temporal areas, providing the first computational account for the emergence of cortical functional specialisation for intentions and decisions.

In the final part I will illustrate how the same neurobiological principles, applied to an extended architecture augmented with sensory (visual) and motor areas, can explain also the emergence of “embodied” – as well as “disembodied” – semantics: our simulation results show how the grounding of the meaning of novel words in sensorimotor brain systems follow directly from the effects of simple neurobiological mechanisms at work within anatomical structures and driven by action and perception processes.

NOTE: The guest talk will take place in Auditorium K, AUH, Building 7, Nørrebrogade