Unity of the organism and the external environment
Vital activity is impossible without continuous contact with the surrounding world: the organism and its habitat represent an indissoluble unity. In higher animals, the nature of this interaction is dictated by higher nervous activity, i.e., the functions of the brain.
The interaction mechanism represents a strict sequence:
- Analysis and synthesis of incoming external influences.
- Comparison of external stimulus characteristics with the current internal state.
- Execution of active movement in response to the situation.
In general, the contact of living beings with the world consists of several components: the work of analyzers, the formation of reflex responses, and purposeful behavior that actively affects the environment. In humans, this list is expanded due to higher forms — mental, cognitive, and labor activity.
External behavioral link and homeostasis
Any active behavior is driven by the work of functional systems at the behavioral level. The physiological meaning of such reactions lies in the limited internal resources of the organism. Internal self-regulation mechanisms are far from always able to independently keep homeostatic parameters within normal limits.
For survival and maintenance of balance, it is vital for the organism to take certain substances from the outside and give back metabolic products. The role that behavior plays in homeostatic systems is called the external behavioral link. It is thanks to this link that the organism actively engages with the environment to restore the disturbed balance.
Systems that necessarily include the behavioral link of self-regulation include mechanisms for maintaining:
- Optimal nutrient levels;
- Body temperature;
- Osmotic pressure;
- Excretory processes;
- Sexual functions.
Special case: blood gas parameters are normally regulated strictly automatically. However, if the organism enters extreme conditions, the gas maintenance system also forcibly activates the external behavioral link.
Reflected reactions and organizational principles
Living beings are in a state of constant response to stimuli. These reflected reactions are essentially adaptive reflex behavioral acts operating as "disturbance-based reactions".
The two leading principles of behavioral organization are recognized as:
- The system principle.
- The reflex principle.
According to reflex theory, any behavioral act is a reaction to the impact of specific environmental factors. A fundamental contribution to the development of this field was made by I.P. Pavlov, who proposed dividing all behavioral reflexes into two basic types: unconditioned (innate) and conditioned (acquired).
Briefly: answers to topical questions
What stages are included in the central architecture of a behavioral act according to P.K. Anokhin?
The central architecture of a behavioral act includes four sequential nodal stages.
- Afferent synthesis — the initial stage of selection, comparison of excitations, and formation of pre-trigger integration (includes motivation, situational afferentation, memory, and triggering afferentation).
- Decision making — the nodal moment of switching from synthesis to an action program, formation of a dominant line of behavior with the elimination of redundant degrees of freedom.
- Action result acceptor — the formation of the apparatus for anticipation, prediction, and evaluation of the future result.
- Efferent synthesis — the organization of the action itself, following decision making and the formation of the anticipation apparatus.
Which brain structures are responsible for the formation of biological motivations?
The formation of biological motivations is ensured by a complex of brain structures, where the leading role belongs to the hypothalamus.
- Hypothalamic centers — play a pacemaker role, subordinating other structures and forming the basis of motivational excitation.
- Limbic structures — participate in the systemic process of forming motivations of various biological qualities and transmit ascending information.
- Reticular formation — exerts nonspecific ascending activating influences on the cerebral cortex.
- Frontal cortex (Cortex frontalis) — receives ascending motivational information, makes decisions, and provides descending control for the realization of purposeful behavior.
What is the physiological difference between conditioned and unconditioned reflexes?
The main physiological difference lies in the mechanism of their origin and the properties of the reactions.
| Characteristic | Unconditioned reflexes | Conditioned reflexes |
|---|---|---|
| Origin | Innate, genetically determined | Acquired during individual life |
| Conditions of occurrence | Action of adequate stimuli on corresponding receptors | Repeated coincidence of an indifferent stimulus with vital activity |
| Properties | Relatively constant | Selective, extremely variable, possess plasticity (dynamism) |
| Nature of the reaction | Response to stimulus impact | Anticipatory reaction characteristic of future reinforcement |
What types of needs are distinguished according to P.V. Simonov's classification?
According to P.V. Simonov's classification, three basic groups of needs are distinguished: biological, social, and ideal (spiritual). Additionally, within this classification, needs are divided according to two criteria:
- By direction vector — needs for oneself (egocentric) and needs for others (social and altruistic) are distinguished.
- By goal — preservation needs (needs whose satisfaction relieves negative emotions) and development needs (growth needs satisfied to obtain positive emotions in the future) are distinguished.
Class and exam questions
What is the physiological meaning of behavior?
Internal self-regulation systems do not always cope with maintaining homeostasis. Behavior allows the organism to actively interact with the environment, consuming or excreting substances to restore balance.
What is the external behavioral link?
This is the specific role played by active behavior within functional systems of the homeostatic level to replenish a deficiency or eliminate an excess of substances.
How are gas parameters regulated in the body?
Under normal conditions, gas level maintenance occurs automatically. The behavioral link is included in this system exclusively in extreme situations.
How did I.P. Pavlov classify behavioral reactions?
Based on reflex theory, I.P. Pavlov divided all behavioral reflexes into two types: conditioned and unconditioned.
What else to study on this topic
- Mechanisms of analysis and synthesis of external influences in the brain
- Differences between conditioned and unconditioned reflexes according to I.P. Pavlov
- Formation of psycho-behavioral level systems to achieve social results in humans
- Physiological essence of adaptive "disturbance-based reactions"
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