General postulates of the systemic organization of behavior
The basis of the theory of functional systems lies in a complete revision of the cause-and-effect relationships of a living organism's activity. Traditionally, physiology considered the executed action itself to be the foundation. However, the systemic approach asserts that the most important and determining property is precisely the useful result of behavior. This result must provide objective adaptive benefit both for a specific physiological system and for the entire organism as a whole.
The formation of any goal-directed act never occurs spontaneously. The initiating force is always the initial needs and the dominant motivations formed on their basis. When an organism develops an acute need, motivation instantly mobilizes available behavioral programs. It is important to note that these programs can be both genetically determined (innate) and individually acquired over the course of life. The main goal of this large-scale mobilization is to achieve that very adaptive result.
Furthermore, internal programming is continuously carried out within functional systems. Based on genetics and accumulated experience, the organism constantly calculates which adaptive results are currently most important and by what optimal methods they can be achieved.
Principle of self-regulation
The most crucial element of the theory is the strict principle of self-regulation. Any behavioral functional system is always structured along the same vector: from the moment a need arises until its complete physiological satisfaction.
The mechanism of this process works cyclically. If the current result deviates from the optimal norm (for example, there is a disruption in normal metabolism or a failure in adaptation processes), this deviation does not require some external regulating command—it inherently becomes a powerful internal stimulus.
A stimulus formed in this way immediately mobilizes all necessary systemic mechanisms. Their sole task is to return the parameters back to normal. As soon as the desired result is objectively achieved, the initial need is satisfied, and the functional system ceases its active work.
Differences from reflex theory
Before the described theory emerged, the classical reflex concept was dominant. The systemic approach put forward fundamentally new provisions, completely eliminating the primacy of external stimuli.
According to the new concept, behavior is determined by far more than just external environmental influences. A huge, and often decisive, role is played by internal needs, accumulated genetic and individual experience, as well as situational afferents (the current environmental context).
The central nervous system operates in a completely different manner. Even before a specific triggering signal appears, a so-called pre-trigger integration of excitations is formed in the brain. This is a latent, yet fully formed readiness for action. The external triggering stimulus acts merely as a key that simply "unlocks" this pre-prepared base.
Non-linearity and future anticipation
Unlike the classical direct reflex arc, systemic excitation unfolds non-linearly. It represents a complex integrative network encompassing multiple structures.
The most unique property of such an organization is the anticipation of real activity results. The brain does not simply react to the fact of an occurred event; it pre-plans what exactly should happen.
This foreknowledge creates ideal conditions for continuous monitoring. An action result acceptor—a special evaluation apparatus—is formed within the system. It continuously compares the properties of the result actually achieved by the organism with the parameters that were initially planned. If reality matches the plan, the behavioral act is considered successfully completed.
Briefly: answers to topical questions
Who is the author of the theory of functional systems?
The author/founder of the theory of functional systems is Pyotr Kuzmich Anokhin, a 20th-century Soviet physiologist, academician, and Lenin Prize laureate. Functional systems are defined as morphofunctional apparatuses that ensure self-regulation in the body. According to the theory of functional systems, the main factor is the useful result of behavior, and the formation of goal-directed behavior is triggered by initial needs and dominant motivations.
What sequential stages (nodal mechanisms) make up the central architecture of a functional system?
The central architectonics of a behavioral act includes the following successive stages of systemic organization:
- Afferent synthesis — the initial stage of information processing and integration.
- Decision making — the formation of the dominant line of behavior.
- Action result acceptor — anticipation of the required result.
- Efferent synthesis — formation of the efferent behavioral program.
- Action.
- Achievement of the result.
- Result evaluation — comparison of the achieved result with the programmed one.
What components make up the stage of afferent synthesis?
The stage of afferent synthesis consists of four main components, the integration of which makes it possible to form the goal of behavior. These include:
- Dominant motivation — the energetic basis determined by the leading need.
- Situational afferentation — static information about the external environment and current conditions.
- Memory — utilization of individual or genetic past experience.
- Triggering afferentation — a specific stimulus that directly initiates the behavioral reaction.
Self-regulation scheme: Deviation → Stimulus → Mobilization → Satisfaction. Deviation from the norm is itself the main stimulus for triggering the system.
Class and exam questions
What is more important in behavior according to this theory: the action itself or its outcome?
The useful adaptive result possesses absolute priority. Any action is secondary and serves merely as a tool to achieve it.
What is the starting point for the formation of goal-directed behavior?
Initial internal needs and dominant motivations. It is they that mobilize innate or acquired action programs.
How does the action result acceptor work?
It allows the organism to act in anticipation. The brain pre-prognosticates the properties of the required result and then constantly compares them with the actually achieved parameters.
Is the external triggering stimulus the main cause of the organism's reaction?
No. External triggering stimuli merely "unlock" the already prepared pre-trigger integration of excitations that was previously created by needs, experience, and situational stimuli.
What else to study on this topic
- Types of useful adaptive results
- Genetically determined behavioral programs
- Mechanisms of dominant motivation formation
- The role of situational stimuli in pre-trigger integration
- Structure and functions of the action result acceptor
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