Systemic Determination of Systemic Determination of Neuronal ActivityNeuronal Activity

In the framework of reactivityparadigm individual's behaviorindividual's behaviorisis aa reaction to stimulus reaction to stimulus. Thisreaction is based on thepropagation of excitationpropagation of excitationalong the reflex arcalong the reflex arc: fromreceptors through centralstructures to effector organs.

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The reactivity paradigm treats neuron as anelement of reflex arc, while its functionis a propagation of excitation.

Thus reactivity paradigm treats neuron quitelogically: neuron, just like an organism,responds to stimuli. Impulses that aneuron receives from other cells act asstimuli, while the response of a neuron isits discharges following the synapticinput.

In the framework of activityactivity paradigmindividual's behavior isindividual's behavior is a a goalgoal--directed actiondirected action. . The principaldeterminant of a behavior is an eventwhich is not in the past with respectto behaviour, that is, a stimulus, butwhich occurs in the future, a a resultresult,which is understood as a desiredrelation between an organism andenvironment.

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А neuron, like any other livinglike any other livingcellcell, realizes a genetic programwhich requires metabolitesrequires metabolitesreceived from other cellsreceived from other cells..

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Neuronal activityNeuronal activity, like a behavior of anorganism, is notis not a a response response,, but but a a way of way ofchanging the relation to environmentchanging the relation to environment,,""actionaction"" that removes discrepancy between"needs" and microenvironment, causingmodifications in blood flow, metabolic inflowfrom glial cells, activity of other neurons.

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Thus, neuronneuron is not an "encodingelement", "conductor", or "summator", but anan organismorganism withinwithin organismorganism, , providingproviding forfor itsits needsneeds withwith metabolicmetabolicsubstancessubstances receivedreceived fromfrom otherotherelementselements.

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Neuron may provide for its metabolic"needs" only by joining with otheronly by joining with otherelements of an organismelements of an organism to form afunctional system.

Achievement ofAchievement of a a result result of abehavioral act appears assatisfying metabolic "needs" ofneurons, and it stops theirstops theiractivityactivity..

Result “from the outside”:

Memory

Motivation

Decisionmaking

Acceptorof action’s

result

Programof the action

Action

Resultof the action

Parametersof the result

Afferentsynthesis

Triggeringstimulus

Environmentalafferentation

Environmentalafferentation

Act n Act n+1 Act n+2T T

Rn

Rn + 1r1 r1 r1r2 r2 r2r3 r3

"From within", at the level of at the level of separate neurons, separate neurons, achievement of a resultachievement of a result appears as satisfying metabolic "needs" of neurons, and it stops their activitystops their activity.

А neuron, like anylike anyother living cellother living cell,

realizes a genetic programwhich requires metabolitesrequires metabolitesreceived from other cellsreceived from other cells.. 1

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The anticipatory nature of reflection that is the principal and specific property of life determines the ability of any individual (both unicellular and multicellular) to prepare for the forthcoming events organized in certain temporal sequences. It is the most fundamental characteristic of the living matter (P. K. Anokhin).

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