The speaker, Dr. Kevin Mitchell of the Smurfit Institute of Genetics and The Institute for Neuroscience, Trinity College Dublin, has provided the following abstract:
There is a paradox at the heart of modern neuroscience. As we succeed in explaining more and more cognitive operations in terms of patterns of electrical activity within specific neural circuits, down to the level of cells and synapses, it seems we move ever farther from bridging the gap between the physical and the mental. Indeed, each advance seems to further relegate mental activity to the status of epiphenomenon – something that emerges from the physical activity of the brain but that plays no part in controlling it. It seems difficult to reconcile the reductionist, reverse-engineering approach to brain function with the idea that we human beings have thoughts, desires, goals and beliefs that influence our actions. If actions are driven by the physical flow of ions through networks of neurons, then is there any room or even any need for psychological explanations of behaviour?
I will argue that the reductionist level of mechanistic causality, where the physical state of the brain necessarily leads to a subsequent state, does not constitute a full explanation of behaviour. Inherent randomness and noise in neural circuits, along with the hierarchical, integrative nature of information processing, means the system is not deterministic at this reductive level. This leaves causal slack in the system for higher-order effects and “top-down causation”, without violating the laws of physics or invoking immaterial forces. The causal power of a thought, while realised by a physical brain state, inheres in the meaning of that state for the organism. These two systems of causality are not in conflict and neither is privileged over the other - one describes mechanism and the other provides explanation. I will discuss the implications of this view for free will and the emergence of agency.