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Cerebellum cognition and consciousness

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Cerebellum cognition and consciousness Powered By Docstoc
					              File for BM – Web (19.2.10)
                              14 figure in all
Power point updates of Figures. 1-11 from Brain/Mind

Plus three supplementary figures:
(a) Cerebellum and cerebrum in sleep/dream process
(b) Daydreaming, imagination and intuition
(c) Input to cerebral/conscious system from the cerebellum:
   (issues relevant to attention deficit aspects of schizophrenia)
Fig. 1 Basic homeostatic circuit
(arranged top to bottom, whereas book version arranged right to left




          New Actual value             Required value attained

                        Comparator              Reference standard            Innate
                                 Error signal
                                                                              Control
                                                                              System
                             Corrective response generator
                                                           Response
                                                           Information
                                                            (cas)
        sensors                                                      effectors

                   Consequence
   NEW STIMULUS                  ENVIRONMENT                     REFLEX RESPONSE
Fig. 2 More complex homeostatic circuit involving a learning based system
(arranged top to bottom, whereas book version arranged right to left)

            Actual value                Required value

                           Comparator          Reference standard                        Learning
                                                                   Response
                                                                   Information (sicas)
                                                                                         Based
                                Error signal             Memory                          Control
                                                                                         System
                            Corrective response generator
                                                                  Response
                                                                  Modifying
                                                                  Information
             Actual value             Required value              (lcas)

                      Comparator               Reference standard
                                Error signal                                     Innate
                                                                                 Control
                            Corrective response generator
                                                                                 System
                                                            Response
                                                            Information
                                                            (icas)
       sensors                                                         effectors


      STIMULUS                ENVIRONMENT                       LEARNED
                                                                RESPONSE
Fig. 3 Simplified homeostatic circuit involving innate and naturomorphic
systems.
(arranged top to bottom, whereas book version arranged right to left)




                               Naturomorphic System
                               Learning based control
                           sicas

                                Reflex Level Control
                                                                   ncas
                                                        icas

                     sensors                            effectors



                    STIMULUS       ENVIRONMENT          RESPONSE
Fig. 4 Simplified homeostatic circuit involving, innate, naturomorphic and
abstract systems.
(arranged top to bottom, whereas book version arranged right to left)
                                                                          Abstract system can
                                                                   acas   exert it own direct
Abstract system can
                                    Abstract System                       control (acas) on the
Selectively attend to               Learning Based Control                effectors, and
information from:                                                         inhibit/over-ride
external environment           acasb                                      Naturomorphic system
                                                            sncas
                                                                          output
OR, from;
Naturomorphic system               Naturomorphic System                    OR: Abstract system can
                                   Learning Based Control                  bias the output (acasb)
                                                                           of the Naturomorphic
                               sicas                         ncas
                                                                           system.

                                    Reflex Level Control                   Potential for
                                                                           sub-programming
                                                                           or rote learning
                                                            icas

                         sensors                            effectors



                        STIMULUS    ENVIRONMENT             RESPONSE
Fig. 5 Part of simplified homeostatic circuit (as in Fig. 4) modified by the
addition of filter to allow for the process of attention


Filtering process:
Abstract system                              Abstract
selects information                          System
for attention
based on abstract           Input
system priorities           Filter                                      Naturomorphic
                                                        sncas
                                                                        system receives
Abstract system may
                                          Naturomorphic                 unfiltered input, and
                                             System                     outputs ‘significant’
(or may not) choose to
                                                                        stimulus information
redirect its attention
                                                                        (sncas) for abstract
according to its abstract
                                                                        system attention.
evaluation of the
information brought to
its attention by the
naturomorphic system




                             sensors                        effectors



                            STIMULUS                       RESPONSE
                                       ENVIRONMENT
Fig. 6 A homeostatic circuit involving innate, naturomorphic and abstract
systems, elaborated to allow attention, sub-programming of the naturomorphic
system, and two levels within the abstract system
                                                                          Retains developmentally
                                                                          early level of abstraction
                        Filter                                            to provide ‘translation’
Abstract system                                                           from Naturomphic level
directed rehearsal of                                                     of information
desirable behaviour                  Abst             Abst                (low discrimination
sequences                                                                 ‘in-effect’ abstraction) to
This creates automatic               High             Low
                                                                          highest level abstraction in
skill production by                                                       Abstract system
naturomorphic system.
BUT, disproportionately
weights these behaviours,            Naturo          Naturo               Retains a naturomorphic
so the naturomorphic                 SubProg        (untouched)           memory that reflects
subsytem no longer                                                        environmental
reflects the natural                                                      contingencies
Environmental
contingencies
                                      Reflex Level Control




                           sensors                            effectors



                         STIMULUS     ENVIRONMENT            RESPONSE
Fig. 7/8 Simple diagram of the brain, showing brain stem, cerebellum and
                                cerebrum
Fig. 9 Schematic model of the brain in terms of brain stem, cerebellum.
(Further simplified from Fig. 9 in Brain/Mind)




                                    Cerebrum




                                       BS                Cere-
                                       &                 bellum
                                       Nuc




                               Sensors       Effectors
Fig. 10 Simplified homeostatic circuit involving innate,
naturomorphic and abstract systems (left hand side as in Fig 4)
redrawn in an arrangement comparable with the simplified model
of the brain (right hand side as in Fig 9)
                                         Abstract
                                         System

             Abstract
             System



           Naturoorphic                                        Naturo-
            System                          Inn.               morphic
                                            Sys
                                                               System
          Innate System




sensors                   effectors   Sensors      Effectors
Fig. 11 Brainstem, Cerebellum and Cerebrum as control subsystems:
Elaborated for hemispheric and evolutionary subdivisions
   (with rearrangement according to simplified brain structure)


                            Cerebrum              Cerebrum
                            Left Hemi             Right Hemi
                                                                       Includes ascending
                                                                       output of vermis
   Includes Archi-cortex,            Cerebrum                          in dreaming
   e.g. Hippocampus.                Assocn. Ctx
   Penfield’s ‘Key-of-access’       & Hippocps
   to sub-cerebro-cortical                                           Neo
   ‘centrencephalic system’’
   memories                                                          Cere-
                                                                     Left
                                                           Archi-&   Hemi
                   Brain                                   Paleo-              Neo
                                                                               cerebellum
                   Stem                                    Cere-               grows with
                     &                                     bellum              Cerebro-
                   Nuclei                                  (Vermis             cerebellar
                                                                               interaction
                                                           & Floc)
                                                                     Neo
                                                                     Cere-
                                                                     Right
                                                                     Hemi
                                 Sensors   Effectors
Supplementary Fig. (a): Cerebellum and Cerebrum in Sleep/Dream Process
(updating the abstract system)

                        During dream sleep the cerebrum (pre frontal cortex?)
                        cannot inhibit (or alter) the input it receives from the cerebellum,
                        (and experiences the information input as though it is from the external world)


Cerebellum sends
                                         Cerebrum                                   NE (LC), NA
updating information                                                                and/or Ach
to Cerebrum in form                                                                 Facilitates
of polymodal                                                                        PGO & D/REM
sequence (Virtual                       Cerebellum
Reality) with visual,                    (vermis?)
auditory, motoric,                                                              Serotonin/5HT (Raphe)
and emotional                                                                   Initiates SWS to prepare
content                                                                         for subsequent D/REM.
                                 Brain Stem & Spinal Cord
                                        Pineal                                  Later, provides for
                                        Locus Coeruleus (LC)                    S/NREM, between
                                        Raphe system                            D/REM phases

                   sensors                                            effectors
                                                                                    WITHIN SLEEP
                                                                                    CONDITION, MOTOR
                                                                                    SYSTEM OUTPUT
               SLEEP CONDITION                                                      TO EFFECTORS IS
               REDUCED                  ENVIRONMENT                                 INHIBITED
               ENVIRONMENTAL
               STIMULUS
Supplementary Fig. (b): Daydreaming, Imagination and intuition/insight
(When conscious attention to Information input from external environment is reduced)


                                                                         The sub-conscious
                                       Cerebrum                          generates
                                      Conscious Control                  responses to situations,
                                                                         and has an opportunity to
                                                                         forward them to the
                                                                         conscious level as
   Conscious                                                             daydreaming,
   attention to
                                     Cerebellum                          ‘spontaneous’
   external                        Subconscious Control                  imagination, (including
   environment is                                                        inner voice)
   reduced
                                                                         The forwarded
                                                                         information could be
                                   Physical /Reflex Control
                                                                         experienced as
                                                                         subconsciously
                                                                         originating
                                                                         Intuitions/insight

                        sensors                              effectors



                      STIMULUS     ENVIRONMENT              RESPONSE
Supplementary Fig.(c): Input to cerebral/conscious system from the cerebellum:
Issues relevant to attention deficit and aspects of schizophrenia


            Reduced attention to sensory input may allow cerebellar information into consciousness

                 Reduced sensory input may allow cerebellar information into consciousness

External stimulus
normally ‘drowns’                                                                            Modified
cerebellar input                                                                             neuro-
to conscious level       Filter           Cerebrum
                                                                                             transmitter
                                          Conscious             Ascending output of          levels may
                                                                cerebellum
Due to updating ‘pressure’
                                                                                             strengthen
strong cerebellar ascending                                                                  cerebellar
                                          Cerebellum            Sub-conscious
output may break into                                                                        output
                                                                imagery,
conscious awareness and                   Sub Consc.            (viusal/auditory)
disrupt attention to input
from external environment,                                      Possibly words/speech
or possible ‘merge ‘ with it
                                  Physical & Reflex control



                      sensors                                         effectors



                      Sensory
                      STIMULUS