Evolution of Evolution of Complex Complex SystemsSystems

Lecture 6: Brain and mindLecture 6: Brain and mind

Peter Andras / Bruce CharltonPeter Andras / Bruce Charlton

peter.andras@ncl.ac.ukpeter.andras@ncl.ac.uk

bruce.charlton@ncl.ac.ukbruce.charlton@ncl.ac.uk

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ObjectivesObjectives

Subsystems of the nervous systemSubsystems of the nervous system Brain structureBrain structure Sensory and motor subsystemsSensory and motor subsystems Information subsystem of the Information subsystem of the

brain: memory and languagebrain: memory and language Language and mindLanguage and mind Identity violation and adaptationIdentity violation and adaptation

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NeuronsNeurons

Specialized cells dealing with Specialized cells dealing with information about the organisminformation about the organism

Special communications: Special communications: neurotransmittersneurotransmitters

Special communication actions: Special communication actions: graded potentials, spikesgraded potentials, spikes

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Nervous systemNervous system

Information subsystem of the Information subsystem of the organismorganism

Higher animals have nervous Higher animals have nervous tissue as a tissue system (tissue as a tissue system ( nervous system)nervous system)

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Subsystems of the nervous Subsystems of the nervous systemsystem

Sensory and motor subsystemsSensory and motor subsystems E.g., olfactory system, visual E.g., olfactory system, visual

system, motor systemsystem, motor system

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Organisation of nervous Organisation of nervous subsystemssubsystems

Ganglions in insects, e.g., olfactory Ganglions in insects, e.g., olfactory lobe, stomatogastric ganglionlobe, stomatogastric ganglion

Each ganglion contains neurons Each ganglion contains neurons communicating about a specific communicating about a specific topic, a part of the self descriptiontopic, a part of the self description

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The brainThe brain

Collection of major ganglions with Collection of major ganglions with specialist integrating components specialist integrating components (integrating ganglions)(integrating ganglions)

E.g., insect brain, octopus brain, cat E.g., insect brain, octopus brain, cat brainbrain

(www.neurobiologie.fu-berlin.de/gruenewald)

(serendip.brynmawr.edu)

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Large brainsLarge brains

Components:Components: Brain stemBrain stem MidbrainMidbrain Limbic systemLimbic system CortexCortex

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Sensory systems – 1 Sensory systems – 1 Components:Components:

Sensory ganglionSensory ganglion Brainstem nucleiBrainstem nuclei Midbrain centresMidbrain centres Limbic centresLimbic centres Cortical areasCortical areas

E.g., auditory system: auditory E.g., auditory system: auditory ganglion, ganglion, cochlear nucleus, superior cochlear nucleus, superior olivary nucleus,olivary nucleus, inferior colliculusinferior colliculus, , medial geniculate body, lateral posterior medial geniculate body, lateral posterior nuclei, reticular nucleus,nuclei, reticular nucleus, auditory cortexauditory cortex

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Sensory systems – 2 Sensory systems – 2

Higher areas are dealing with more Higher areas are dealing with more detailed information using more detailed information using more abstract descriptionsabstract descriptions

E.g., visual system: V1, V2 – E.g., visual system: V1, V2 – oriented bars, continuous lines; V2, oriented bars, continuous lines; V2, V4 – colour, shape; V3, V5 – V4 – colour, shape; V3, V5 – motion, locationmotion, location

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Motor systemMotor system

Cortical motor areaCortical motor area CerebellumCerebellum Lower brain centresLower brain centres Motor nerve ganglionsMotor nerve ganglions M

ore

abst

ract

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Association areasAssociation areas

Cortical areas not directly involved Cortical areas not directly involved in sensory-motor processesin sensory-motor processes

Large part of the cortexLarge part of the cortex E.g., human brainE.g., human brain

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Integration of neural Integration of neural subsystemssubsystems

Association neural subsystemsAssociation neural subsystems Integrates information form other Integrates information form other

subsystemssubsystems

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Communications in neural Communications in neural subsystemssubsystems

Specialized content, special Specialized content, special references, special language of references, special language of activity patternsactivity patterns

The same basic unit neurons The same basic unit neurons communicate by neurotransmitters communicate by neurotransmitters using spikes as communication using spikes as communication actionsactions

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System boundary of neural System boundary of neural subsystemssubsystems

Intense communication within the Intense communication within the subsystem about the sensory subsystem about the sensory perceptions or motor commands perceptions or motor commands related to the specialist topicrelated to the specialist topic

Relatively low amount of Relatively low amount of communications with the outside communications with the outside of the subsystemof the subsystem

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Meaningful and Meaningful and meaninglessmeaningless

Meaningful: interpretations that fit the Meaningful: interpretations that fit the specialist modelspecialist model

Meaningless: unsolvable interpretation Meaningless: unsolvable interpretation problems, i.e., the received sensory problems, i.e., the received sensory information cannot be interpreted / information cannot be interpreted / understood within the limits / the understood within the limits / the language of the specialist subsystem language of the specialist subsystem identity violationidentity violation

E.g., hallucinationsE.g., hallucinations

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Memory and the nervous Memory and the nervous systemsystem

Memory: recordings of earlier Memory: recordings of earlier communications within the communications within the nervous systemnervous system

E.g., memories of earlier neural E.g., memories of earlier neural communications representing communications representing perceptions and actionsperceptions and actions

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Information subsystem of an Information subsystem of an information subsysteminformation subsystem

Interactions between memoriesInteractions between memories Virtual planning of actions using Virtual planning of actions using

memories, evaluation of new memories, evaluation of new perception using memoriesperception using memories

Memory processing Memory processing information information subsystem of the nervous systemsubsystem of the nervous system

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Long-term memoryLong-term memory

Communications between Communications between memories memories short-term planning short-term planning

Memories of communications Memories of communications between memories between memories long-term long-term memorymemory

Dreaming – communications Dreaming – communications between long-term memoriesbetween long-term memories

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Memory and brainMemory and brain

Understanding / interpreting / modelling Understanding / interpreting / modelling the perception and action generation by the perception and action generation by the nervous systemthe nervous system

Short-term memory and long-term Short-term memory and long-term memorymemory

Communications about the functioning Communications about the functioning of the brainof the brain

This is the role of the association areas This is the role of the association areas organized as a systemorganized as a system

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‘‘Who am I ?’Who am I ?’

The main question of the information The main question of the information subsystem of the brain: what neural subsystem of the brain: what neural communications are correct, which communications are correct, which are part of the correct informational are part of the correct informational model model system identity system identity

Deciding what is ‘I’ and what is not ‘I’Deciding what is ‘I’ and what is not ‘I’ Communications about the proper Communications about the proper

interpretation of neural interpretation of neural communicationscommunications

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Actions of the information Actions of the information subsystemsubsystem

Identity definition, identity Identity definition, identity checking, identity enforcementchecking, identity enforcement

Communications questioning the Communications questioning the correctness of interpretations correctness of interpretations generating questioning actions: generating questioning actions: intentional actionsintentional actions

E.g., intentional body movementsE.g., intentional body movements

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Perceptions of the information Perceptions of the information subsystemsubsystem

Analysis of interpretations by Analysis of interpretations by neural subsystems in order to neural subsystems in order to decide what perception decide what perception interpretations are part of the interpretations are part of the proper self, which fit the identity of proper self, which fit the identity of the systemthe system

E.g., conscious perceptionsE.g., conscious perceptions

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Memory and languageMemory and language

Communications between long-Communications between long-term memoriesterm memories

Language: the language of Language: the language of communications about long-term communications about long-term memories – memories of memories – memories of communications between long-communications between long-term memoriesterm memories

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Language and referenceLanguage and reference The language deals with the self identity, with The language deals with the self identity, with

what is intentional and what is not, and what is what is intentional and what is not, and what is consciously perceived and what is not, what is consciously perceived and what is not, what is part of the identitypart of the identity

These communications are based on a specialist These communications are based on a specialist neural communication language representing neural communication language representing the communication signals of the identity the communication signals of the identity systemsystem

In humans this is the identity defining language In humans this is the identity defining language that we use to monologue about ourselvesthat we use to monologue about ourselves

Such communications refer to earlier ones and Such communications refer to earlier ones and their root is the initial question of defining the ‘I’their root is the initial question of defining the ‘I’

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The mindThe mind

The communication system about the The communication system about the conscious identity constitutes the mind conscious identity constitutes the mind – the core of the information subsystem – the core of the information subsystem of the brainof the brain

The mind’s language is the internal The mind’s language is the internal language used to communicate about language used to communicate about long-term memories and identity. It is long-term memories and identity. It is aimed to decide what is part of ‘I’ and aimed to decide what is part of ‘I’ and what is not what is not personality personality

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The mind subsystem of the The mind subsystem of the nervous systemnervous system

Boundary: dense communications about Boundary: dense communications about the identity of the self, rare the identity of the self, rare communications with other parts of the communications with other parts of the brain, i.e., getting the info that is brain, i.e., getting the info that is analysed in many detailsanalysed in many details

It is a subsystem of the nervous system It is a subsystem of the nervous system like the sensory subsystems, but this like the sensory subsystems, but this deals with the information subsystem of deals with the information subsystem of the nervous system the nervous system identity subsystem identity subsystem

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Meaningful Meaningful communicationscommunications

Communications about the identity Communications about the identity that reference other such that reference other such communications and are communications and are referenced by further referenced by further communicationscommunications

These communications fit with the These communications fit with the identity of the systemidentity of the system

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Language grammarLanguage grammar

The grammar: conditional The grammar: conditional continuation distributions are the continuation distributions are the grammatical rules of human grammatical rules of human language in the case of humanslanguage in the case of humans

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Meaningless Meaningless communicationscommunications

Communications that do not fit the Communications that do not fit the identity of the personalityidentity of the personality

These end up with contradictions, These end up with contradictions, communications about which it is communications about which it is impossible to decide whether they impossible to decide whether they are about a part of the identity or are about a part of the identity or not not identity violations identity violations

E.g., self-analysis paradoxesE.g., self-analysis paradoxes

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Happiness and euphoriaHappiness and euphoria

The identity self perception when The identity self perception when limit expectations about the limit expectations about the identity are confirmed, i.e., low identity are confirmed, i.e., low probability conditional probability conditional continuations are experienced continuations are experienced about the identityabout the identity

Euphoria: extreme happinessEuphoria: extreme happiness

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Sadness and depressionSadness and depression

The identity system runs into paradoxes The identity system runs into paradoxes repeatedly or into communications repeatedly or into communications contrary to the expectations, i.e., zero contrary to the expectations, i.e., zero probability continuation probability continuation communications are experienced, which communications are experienced, which do not fit into the identity modeldo not fit into the identity model

Identity violations (faults, errors) add up Identity violations (faults, errors) add up to system failureto system failure

Depression: extreme sadnessDepression: extreme sadness

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SuicideSuicide

Communications about the identity Communications about the identity that lead to the destruction of the that lead to the destruction of the identity system by running regularly identity system by running regularly and frequently into paradoxesand frequently into paradoxes

The identity system is not The identity system is not maintained, which triggers maintained, which triggers corresponding actions of the nervous corresponding actions of the nervous system and of the organism – system and of the organism – complete system failurecomplete system failure

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Multiple-personality Multiple-personality disorderdisorder

Due to paradoxes the identity Due to paradoxes the identity system divides into subsystems system divides into subsystems developing individuallydeveloping individually

Alternatively: a replication of the Alternatively: a replication of the identity system aimed to extend identity system aimed to extend the identity systemthe identity system

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Pharmacological Pharmacological interventionsinterventions

By changing the environment of By changing the environment of the organism’s neurons the neural the organism’s neurons the neural communications changecommunications change

Such changes may favour the Such changes may favour the generation of euphoria (drugs) or generation of euphoria (drugs) or depression (lack of drugs in depression (lack of drugs in addicts) by facilitating the addicts) by facilitating the appropriate communicationsappropriate communications

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Adaptation in the mind – 1 Adaptation in the mind – 1

Conflicting conclusions about the Conflicting conclusions about the identity of the self are resolved by identity of the self are resolved by identity revisionsidentity revisions

Identity revision: elimination of the Identity revision: elimination of the root of the paradoxical situation by root of the paradoxical situation by imposing additional constraints on imposing additional constraints on identity communications (prevention identity communications (prevention of the re-occurrence of the root)of the re-occurrence of the root)

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Adaptation in the mind – 2Adaptation in the mind – 2

Identity revision:Identity revision: Identity definition: ‘I am researcher, and I Identity definition: ‘I am researcher, and I

am not a technician’am not a technician’ Identity checking: ‘I will wear the blue shirt, Identity checking: ‘I will wear the blue shirt,

and have a tie, that fits really with me being and have a tie, that fits really with me being a manager’a manager’

Identity enforcement: ‘I have to sell the Identity enforcement: ‘I have to sell the house, everybody in my circle lives in the house, everybody in my circle lives in the posh part of the city – living here makes me posh part of the city – living here makes me look really ridiculous’look really ridiculous’

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Subsystems of the mindSubsystems of the mind

Communications about the self Communications about the self identity specialized in some identity specialized in some aspects of the identityaspects of the identity

E.g., professional identity, within-E.g., professional identity, within-family identity (in humans)family identity (in humans)

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Brain complexityBrain complexity

Brains without memory and Brains without memory and information subsystem are less information subsystem are less complex; i.e., those with little complex; i.e., those with little associative structures, e.g., jellyfishassociative structures, e.g., jellyfish

Brains with memory and Brains with memory and information subsystem are more information subsystem are more complex; i.e., those with more complex; i.e., those with more associative structures, e.g., catassociative structures, e.g., cat

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Cortex complexityCortex complexity

The cortex is the most developed The cortex is the most developed associative structure in associative structure in vertebratesvertebrates

More associative cortex More associative cortex more more complex brain / nervous system / complex brain / nervous system / organismorganism

More complex identity More complex identity personalitypersonality

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SummarySummary

Nervous systemNervous system Sensory and other sub-systemsSensory and other sub-systems The brainThe brain Information subsystem of the Information subsystem of the

nervous system: mindnervous system: mind Identity violation and adaptationIdentity violation and adaptation Complexity of brain and mindComplexity of brain and mind

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Q&A – 1 Q&A – 1

1.1. Is it true that the nervous system of most Is it true that the nervous system of most animals has a visual subsystem ?animals has a visual subsystem ?

2.2. Is it true that centres of subsystems of insect Is it true that centres of subsystems of insect nervous systems are organized in nervous systems are organized in ganglions ?ganglions ?

3.3. Is it true that insects usually have large Is it true that insects usually have large associative ganglions ?associative ganglions ?

4.4. Is it true that visual illusions are meaningful Is it true that visual illusions are meaningful communications within the visual subsystem communications within the visual subsystem ??

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Q&A – 2 Q&A – 2

5. Is it true that the key question of the identity 5. Is it true that the key question of the identity subsystem is ‘Who am I’ ?subsystem is ‘Who am I’ ?

6. Is it true that the mind is an independent 6. Is it true that the mind is an independent system from the brain ?system from the brain ?

7. Is it true that self-analysis paradoxes lead to 7. Is it true that self-analysis paradoxes lead to damages in the mind system ?damages in the mind system ?

8. Is it true that the lack of reproduction of the 8. Is it true that the lack of reproduction of the identity system due to paradoxes may lead to identity system due to paradoxes may lead to triggering self-destruction ?triggering self-destruction ?

9. Is it true that brains with more associative 9. Is it true that brains with more associative structures characterise more complex structures characterise more complex organisms ?organisms ?