How normal behavior is formed
Any behavioral act relies on engrams—specific neuronal patterns that link cells and synapses in the brain. With constant reinforcement, this memory trace is refined.
When a person develops a need, the dominant motivational state activates engram elements from past experience. Excitation is directed to structures storing information on how to satisfy this need. A key link here is the action result acceptor (ARA)—a selectively excited cortico-subcortical apparatus. It continuously compares reverse afferentation (signals from actual environmental stimuli) with the programmed result, thereby directing our behavior.
Biological and social aspects of motivation
Innate biological motivations (nutritional, defensive, aggressive, sexual) participate in personality formation from early childhood. The predominance of one of them determines individual character traits.
However, the leading role in personality formation belongs to social motivations, which are established under the influence of the environment. It is pronounced motivation that makes a person purposeful, compels them to act actively, aligning their actions with the legal and moral norms of society.
Pathogenesis of pathological motivations
Pathological motivations (substance use disorder, alcoholism, smoking) represent artificially created drives.
They are based on alterations in the metabolic reactions of neurons within hypothalamic structures of the brain. There, artificial pacemakers (rhythm drivers) are formed. When a psychoactive substance is absent, these pacemakers generate powerful excitation that engulfs brain structures and causes an irresistible craving for the drug or ethanol.
Modern therapy principles are based on this mechanism. Since artificial pacemakers exhibit increased sensitivity and vulnerability compared to normal elements of excitation, their metabolism becomes the primary target of treatment. Disruption of this vulnerable link leads to the collapse of the entire pathological system and associated behavioral skills.
Distortion of basic needs using alcoholism as an example
Addiction can "parasitize" biological drives, using their energy to realize a pathological craving. A striking example is the effect of ethanol on the osmotic need (thirst).
- Norm. During cellular dehydration, a signal from receptors travels to the hypothalamus, and from there to the cerebral cortex. "Water-seeking" behavior is formed.
- Acute ethanol exposure. Alcohol inhibits neural networks and blocks the connection between the stimulus and cortical centers. The normal response is suppressed despite worsening dehydration.
- Chronic stage. Motivation switching occurs. Osmotic discomfort no longer activates the "thirst center." Excitation is intercepted by the pathological system and travels via new pathways to the cortex. The body interprets the distress signal not as a need for water, but as a need for a new dose of the substance. "Ethanol-seeking" behavior is triggered.
Classification of motivational disorders
Selective motivational disorder often leads to the formation of a psychopathological personality. Disturbances can proceed in two directions:
- Enhancement: bulimia (excessive hunger), polydipsia (pathological thirst), hypersexuality.
- Suppression: aphagia (refusal of food), adipsia (absence of thirst), impotence.
Briefly: answers to topical questions
Which neurotransmitter systems provide reinforcement during the formation of pathological motivation?
Reinforcement during the formation of pathological motivation is associated with the reward system, whose neurotransmitters are:
- dopamine;
- norepinephrine;
- serotonin;
- endogenous opioids.
Psychoactive substances cause the release of additional amounts of these neurotransmitters from stores, which is accompanied by a feeling of euphoria, comfort, increased work capacity, and the formation of a persistent craving.
For the dopamine hypothesis, it is indicated that drugs stimulate dopamine release in the reward system—nucleus accumbens, causing positive emotions. Endogenous opioids are represented by endorphins and enkephalins, which are localized in the "pleasure centers."
Class and exam questions
What is the role of the Action Result Acceptor (ARA) in behavior formation?
The ARA is a complex of cortico-subcortical apparatuses that directs behavior toward satisfying the dominant need. It constantly compares information from the external environment with the expected result.
Why can a person with chronic alcoholism not simply quench their thirst with water?
Due to the formation of a pathological system. The natural osmotic need ceases to activate normal pathways and instead triggers artificial neural connections that form alcohol-seeking motivation.
What is the pacemaker theory of addiction therapy?
Therapy aims to selectively affect the metabolism of pathological pacemakers in the hypothalamus. They possess high vulnerability, and their destruction leads to the collapse of the entire system of artificial craving.
What else to study on this topic
- Strategy A: formation of behavior through afferent synthesis and decision-making
- Strategy B: mechanism of imprinting and primary tracing on ARA structures
- Symptom-temporal architecture of engram formation
- Character typology based on the dominance of innate biological motivations
- Efferent synthesis in the classical scheme of a functional system
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