Informational aspect of the functional system
The content of a functional system directly depends on the characteristics of the result that the organism is trying to achieve. A specific informational equivalent of this outcome is formed within the system.
Levels of informational content vary depending on the goal:
- Physicochemical level: operates when the result is associated with the maintenance of internal parameters (homeostasis, metabolism).
- Sign (speech) level: characteristic exclusively of human behavioral activity. The ability to associate uttered sounds with objects in the world has led to words becoming an abstraction from reality. They carry semantic and emotional meaning, acting as powerful conditioned stimuli.
Motivation and the formation of the "functional framework"
Dominant biological motivation (alimentary, defensive, sexual) genetically programs the properties of stimuli that will bring satisfaction. This process is constantly corrected and improved through individual learning.
The guiding component (vector) of motivation programs the parameters of the required result. This is necessary for the constant comparison of reality with expectation, behavioral regulation, and error correction.
The interaction between motivation and reinforcement (satisfaction of a need) occurs on a complementary principle, often involving the same neurons of the brain.
Key mechanisms at the neuronal level:
- Change in activity pattern: In a state of strong motivation (e.g., hunger), sensorimotor cortex neurons generate burst-like activity—groups of impulses interrupted by pauses. After food intake, the rhythm changes to an even, regular one.
- Role of pacemakers: Hypothalamic motivational centers act as pacemakers. They "tune" the cortex: neurons that previously did not respond to stimuli begin to perceive them. If pacemakers are experimentally destroyed, brain cells cease to respond to reinforcement.
- Concept of the "Functional framework": Dominant excitation creates a specific cortico-subcortical complex of excited neuronal, glial, and synaptic elements in the brain. Subsequent reinforcing signals record experience onto this ready-made "framework" in the form of a distinct pattern.
Architecture of the behavioral act (according to P.K. Anokhin)
The deployment of a behavioral act obeys strict cybernetic principles and goes through several mandatory stages.
I. Afferent synthesis (AS) This is the initial stage that answers the question "What to do?". Four information flows are integrated in this block:
- Motivation (M): current dominant need.
- Situational afferentation (SA): static environmental conditions.
- Memory (M): retrieval of past experience in solving similar problems.
- Triggering afferentation: a specific trigger stimulus initiating the reaction right now.
II. Decision making (DM) The logical completion of the previous stage. From many possible options (degrees of freedom), the system selects a single line of behavior, forming a specific goal.
III. Formation of the program and the apparatus of anticipation Subsequently, processes develop in parallel:
- Efferent synthesis (ES): creation of the program of motor commands ("How to do?").
- Action result acceptor (ARA): the key block of anticipatory reflection. Here, an ideal neural model of the future result is formed and stored even before the action is performed.
IV–V. Action, result, and feedback afferentation The organism performs a goal-directed action that alters the environment, producing a specific result. The parameters of this outcome are captured by receptors, and a stream of impulses (feedback afferentation) returns to the brain, entering the ARA block for evaluation.
Results of comparison (matching) in the ARA:
- Match: the actual outcome corresponds to the prediction. A positive emotion arises, and the action concludes. A reinforcement image is formed—successful experience is fixed in memory, and excitation in the motivation center decreases.
- Mismatch: the outcome is erroneous. A negative emotion arises, and an exploratory-orienting reaction is triggered. The system is forced to restructure afferent synthesis and try again.
Briefly: answers to topical questions
What functions does triggering afferentation perform in the stage of afferent synthesis?
Triggering afferentation serves as a specific stimulus that initiates a behavioral reaction at the given moment.
In the stage of afferent synthesis, it provides:
- Unveiling integration — unveils the pre-trigger integration in the CNS that had formed prior to the action of this stimulus.
- Determining dominance — determines the dominance of the behavioral reaction in each specific case.
How does situational afferentation physiologically differ from triggering afferentation?
Situational afferentation informs about static conditions and prepares the organism for action, whereas triggering afferentation is the trigger for the immediate initiation of the reaction.
| Sign | Situational afferentation | Triggering afferentation |
|---|---|---|
| Character of information | Information about the external environment and static conditions | A specific stimulus at the given moment |
| Role in the CNS | Creates pre-trigger integration and revives programs | Unveils the established pre-trigger integration |
| Functional outcome | Activates memory apparatuses, prepares for the task | Determines dominance, triggers the behavioral reaction |
What types of useful adaptive results are distinguished in P.K. Anokhin's theory of functional systems?
In the theory of functional systems, the content of the system depends on the characteristics of the achieved result: an informational equivalent of the useful adaptive result is formed within it.
Two levels of informational content of the system are distinguished:
- Physicochemical level — if the result is characterized by physicochemical properties, e.g., related to homeostasis or metabolism, the functional system operates at the corresponding physicochemical informational level.
- Sign (speech) level — characteristic of behavioral activity, especially in humans; if the result has speech or sign parameters, the informational content of the system reflects these properties.
For a verbal result in humans, specific features are noted: it is associated with emotional or semantic meaning; a word represents an abstraction from reality and acquires the significance of a conditioned stimulus.
To easily recall the 4 components of the afferent synthesis stage, use the mnemonic POMP (like a pump that "inflates" and initiates behavior): Memory (Memory), Situational afferentation, Motivation, Triggering afferentation.
Class and exam questions
What is the action result acceptor (ARA)?
This is the neural apparatus of anticipation. Based on past experience and current motivation, an ideal model of the expected result is formed within it even before the action itself begins.
How does neuronal activity change upon need satisfaction?
In a state of dominant motivation (e.g., during hunger), cortical neurons show burst-like activity (impulses alternate with pauses). Following reinforcement (eating), the activity changes to ordered and regular.
What happens when the prediction and the actual result do not match?
A mismatch is recorded in the ARA apparatus. This causes a negative emotion, activates the exploratory-orienting reaction, and restarts the process of afferent synthesis to correct behavior.
What else to study on this topic
- Electrophysiological patterns: detailed analysis of bursting and regular neuronal activity.
- Chemical regulation: mechanisms of the influence of neuropeptides and immunomodulators on the interaction of excitations.
- Motivation pacemakers: localization in the hypothalamus and consequences of their experimental destruction.
- Formation of the "reinforcement image": how a successful result is fixed in the memory block.
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