Luca Nanetti - Strange materials, curious methods: Information loops in the brain

A more complex scenario is represented by the management of a situation of equilibrium, or, better, if and when a situation of equilibrium must be either kept, or broken. The very act of physical ‘standing’ involves a delicate balance of antagonist muscles; when we want to take a step that balance needs to be broken. A similar scenario presents in decision making. The Italian folklore reports a starving donkey who cannot choose between two equivalent heaps of hay; amusing and paradoxical how it sounds, one can wonder about how much different is actually our behaviour when we spend way too much time hesitating between, say, two different bottles of olive oil at the supermarket: in both cases the protagonist’s well-being depends from disrupting an equilibrium.

The central nervous system provides wonderfully flexible mechanisms to cope with the problematic situations depicted above; the outlines of the main pathways of information flows will be illustrated in the first part of the Colloquium, also using elements of embryology. A short introduction to how the ‘hardware’ wiring of the central nervous system is investigated will close the first section.

The second part will focus on an important brain subsystem: the basal ganglia. This group of structures is responsible for a number of both ‘logical’ and ‘physical’ subsystems, from skeletomotor management (the ‘standing up’ mentioned above), to decision making (the donkey dilemma), to emotion regulation, to … a lot more. Receive and classify information; wait for an equilibrium to be broken by either the reaching of a critical mass, or by the arrival of crucial information; take a decision in terms of ‘positive’ or ‘negative’ advice to other brain structures. This is the crucial role played by basal ganglia.

The last part of the Colloquium will be about an advanced technique, borrowed from econometrics, called ‘Granger Causality’, which potentially can show the direction of the information flow, and consequently which brain structures ‘rule’ the behavior of other parts depending on the cogent situation.