Anti Cortical-centric Theories of the Brain: Yeah Basal Ganglia!


We are active opponents to the neo-cortex, frontal lobes and even cortical theories of behavior in any animals and especially humans.  While the dominant theory, especially in American “neuro-science” and funding, it just seems like most cultural beliefs in human exceptionalism and anthropomorphizing of brain science, aka, really dum.

My reading is that behavior happen really, really fast in the brain regions closest to the brain stem and spinal cord….which seems intuitive, but no to (mainly American) brain science funding sources.  This is a longer argument, but some new basal ganglia research gives us more ammo….grrrr

(Basal ganglia) neurons’ response properties and their influence on behaviour point to the possibility that they could play a fundamental role in evaluating action outcomes.

The basal ganglia, a group of subcortical nuclei, play a crucial role in decision making by selecting actions and evaluating their outcomes…information about the selection and evaluation of actions is channelled through distinct sets of basal ganglia circuits, with the GPh representing a key locus where information of opposing valence is integrated to determine whether action outcomes are better or worse than expected.

The GPh, a phylogenetically conserved non-motor output of the basal ganglia, excites the lateral habenula (LHb) that, in turn, drives inhibition onto dopamine neurons when an outcome is worse than expected. GPh neurons may thus play a key role in evaluating action outcomes by providing a source of “prediction error (PE)” to the reward system, to drive reinforcement learning…Another hallmark of PE coding is that neurons respond when an expected outcome is omitted…

– When an expected punishment was omitted, putative GPh neurons displayed a decrease in firing either compared to when the punishment was delivered or compared with baseline.
– In contrast, upon omission of an expected reward, putative GPh neurons showed an increase in firing rate relative to delivery of the reward, and relative to baseline.

Together, these results demonstrate that GPh neurons encode reward and punishment PEs, bidirectionally signaling when an outcome is better or worse than expected…excitation and inhibition of the GPh have opposing motivational valence, with the former being aversive and the latter rewarding.

Together, our results demonstrate that the GPh is a key locus where information of opposing valence is integrated, from a subset of basal ganglia circuits, to determine if an action is better or worse than expected. The outcome evaluation function of the GPh is likely mediated through bidirectional control of dopamine neurons, in which PE coding is critical for reinforcement learning. The GPh is well placed to bidirectionally influence dopaminergic activity …We propose that an increase in GPh activity when an outcome is worse than expected increases the excitatory drive onto the LHb to inhibit dopamine neurons and discourage actions, whereas decreases in GPh activity when an outcome is better than expected remove the tonic excitation of the LHb to increase dopaminergic activity and reinforce actions

Accelerated Article Preview Letter doi:10.1038/nature19845 A basal ganglia circuit for evaluating action outcomes, Marcus Stephenson-Jones, et al


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