QC at the Cerebellum

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The Cerebellum - UBC Neuroanatomy
-> https://www.youtube.com/watch?v=17mxfO9nklQ

OBSERVE CLOSELY:

  1. In the cerebellum neurons are in a large number parallel GROOVES
    while in the neocortex neurons are in a folded sheet.

  2. In the cerebellum neurons make few connections (100+) along a single direction
    while in the neocortex neurons make many connections (1000+). in any direction.

  3. In the cerebellum adjacent neurons are related to actions or events happening chronological after each other (close to each other in time)
    while in the neocortex adjacent neurons are related to actions or events that are similar (close to each other in space) e.g. “pixels” on the retina.

  4. In the cerebellum neurons are programmed by input from the neocortex (motor output of neocortex is input for cerebellum)
    while in the neocortex neurons are programmed by input from the senses (perception like vision, touch, hearing, taste, balance,…)

  5. In the cerebellum neurons are mainly used for procedural and time sequential execution
    while in the neocortex neurons are mainly used for recognition and reasoning (association and correlation and simulation)

  6. In the cerebellum neurons are arranged in a topology based on time
    while in the neocortex neurons are arranged in a topology based on space.

  7. In the cerebellum perception input is used to activate responses (such a response can be starting a sequential thread in the cerebellum)
    while in the neocortex perception input is used to synchronize sequential steps (each next step is waiting for feedback from touch or muscle position).

  8. In the cerebellum neurons pulse source input (from the hippocampus) is used to enforce a specific type of recognition (e.g. searching visually for your car-keys feeds the visual car key qualia neuron group)
    while in the neocortex pulse source input (from the hippocampus) is used to activate a single step in sequential thread in a neuron groove (pulse stream is directed to the next step by neurons that fire on feedback)

NOTE: do not try google this and come complaining when you don’t find it confirmed (Digitronic proprietary research results have never been published). This description is our personal vision and therefor I do not claim nor request anybody to agree.

(Mark A Peaty) Stephan, I have not yet watched the video [I have to go out in a minute] but just want to say I read an article some time ago which seemed to make very good sense to me.
It said that the cerebellum acts as a monitor of outcomes resulting from cortical command outputs. The crux of the idea is that if the resulting movement, perception, whatever aligns with expectations, ie is the same as previous results of those commands, then the feedback from muscles, etc is prevented from reaching the cortex thus freeing up cortex to deal with unexpected outcomes.
This makes a lot of sense to me; in effect the cerebellum is seen to be guardian of useful habits.
:slight_smile:

(Stephan Verbeeck) Mark A Peaty That is about right, but not 100% correct.
The darwinistic advantage of having a cerebellum is that it indeed offloads the neocortex from tedious motor control actions allowing you to concentrate on other things than lifting foots alternating left right while walking. Without the cerebellum you would not be able to walk properly without focusing on walking (which leaves you pretty defenseless because that would require doing complicated upper body motor commands at the same time).

So the cerebellum learns from the sequence of actions that you do deliberately and builds neuron pathways that can do the same actions in the same sequence but then without the neocortex doing more than here and there gently giving a nodge to slightly correct the cerebellum sequential thread of execution.

But as to quality correction it is the other way around.
It is the neocortex that has to intervene and correct when the sequence (e.g. dancing) was not correct so if you want to alter a previously learned motor sequence then again you have to focus on it and deliberately contradict (overrule) the cerebellum actions and the cerebellum will then also learn these correction (integrate them in the existing sequence/thread of neurons firing).

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this is excellent information, IMO especially because of your #1 observation,

“In the cerebellum neurons are in a large number parallel GROOVES while in the neocortex neurons are in a folded sheet.”,

I say (my theory) that what the cerebellum does is to behave as

  1. a multitimer peripheral sense organ to the neocortex (and underlying structures) such that durations (from fractions of a millisecond to multiples of days) can be sensed via the cerebellum as it marches through it’s ordinary function, [when any engram forms, it carries a start time attribute into the cerebellum, and when the engram is significantly succeeded by another, the other engram is provided with an ‘offset’ timing attribute that is the difference between ‘now’ and the ‘start’]
    AND
  2. a delay circuit which can be complex-ed with motor behavior to facilitate coordination, by adding appropriate waits to the next step in practiced sequenced movements.
    timing requires bland linear circuitry such as the parallel grooves enables.
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“She had to think about every step that she took.”

“The cerebellum is the part of the brain that’s concerned with making movements coordinated and organizing how you balance. I t also helps to organize a few other things such as the way you put words and sentences together.”

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