Zenith Grant Awardee

Woodrow Shew

University of Arkansas

Project Title

Physical Constraints on Mental Information Capacity and Information Output

Project Summary

How is a thought translated into bodily action? What keeps in check those thoughts which do not translate into action? Answers to these questions strike at the heart of how we behave and interact with the world. From another perspective, the brain is just a complicated chunk of atoms and, as such, constitutes one of the most complex information processing entities in the physical world. Here we propose experiments which aim to discover new principles governing information transfer from the brain to the outside world. Our promising initial experiments as well as previous work suggests that the physics of phase transitions (e.g. water to steam, paramagnetism to ferromagnetism) holds the key to profound new progress on this aim. By tuning the nature of the synapses which mediate interactions among brain cells, we may tune the brain through a phase transition. Our experiments will directly test the new idea that when the brain is poised at the tipping point of a phase transition, it is most capable of translating thought into action.

Technical Abstract

The cerebral cortex is a highly non-equilibrium physical system. Creation, dissolution and flux of information (entropy) among cortex neural circuits is ceaseless. Some of this information enters the brain via the sensory nervous system and some of it is output via the motor nervous system. Here our aim is to delineate fundamental mechanisms, both biological and physical, which limit or facilitate information transfer from the cortex to the body. Based on our published experimental and theoretical work as well as promising preliminary experiments, we hypothesize that the cortex normally operates in a dynamical regime near the critical point of a phase transition. By doing, the brain-body system may achieve maximal information transfer from cortex to behavior. We will test this by pharmacologically tuning the cortex of awake, behaving rats away from its normal operating regime and experimentally quantify this information transfer. We will measure motor cortex dynamics with microelectrode arrays and body dynamics with a precise multicamera motion tracking system. Information theoretic data analysis will be used to assess brain-to-body information transfer. Our expected results would establish a previously unappreciated foundational role of critical phenomena in how organisms function and affect information in their physical environment.