Biological Significance and Essence of the Phenomenon
Living organisms do not simply react mechanically to stimuli, but are capable of predicting the consequences of their actions. This process is inextricably linked with the mechanisms of afferent synthesis and decision-making.
The formation of the action result acceptor reflects the goal-setting process and relies on dominant motivation. For example, when a person anticipates how an exam will go or what they will buy at the store, this exact apparatus is at work. Past reinforcements — the experience of interacting with factors that previously helped successfully satisfy social or biological needs — serve as its base.
Neurophysiological Mechanisms
Interneurons of various brain regions form the basis of the apparatus. The process of forming prediction includes several stages:
- Preparation and Decision. Pyramidal neurons of the cerebral cortex process motivational, triggering, and situational influences, engaging memory mechanisms. This culminates in decision-making, expressed in a specific configuration of nerve impulses.
- Efference copy. Motor commands are sent via the pyramidal tract to effector organs. Simultaneously, exact copies of these commands are transmitted via special branches (collaterals) to interneurons. This creates the predictive model.
- Matching (Slichenie). When the real result is achieved, the signal regarding its parameters (feedback / reverse afferentation) returns to the same interneurons. A comparison between the prediction and reality takes place.
The dynamics of ARA formation go through three stages. At the activation stage, motivation via collaterals excites the neural network. At the reinforcement stage, signals about the achieved success selectively consolidate the required connections. Ultimately, the anticipatory excitation stage forms: upon a new appearance of motivation, the brain activates the entire neuronal ensemble in advance, anticipating the outcome.
What Happens During Mismatch: The 'Surprise' Effect
To experimentally prove the existence of the predictive apparatus, physiologists use the substitution of expected reinforcement. If the prediction does not match the fact, a mismatch (ras soglasovanie) occurs.
A classic example from P.K. Anokhin's laboratory: a conditioned reflex was established in a dog to receive a meat-rusk powder. In one experiment, the powder was imperceptibly replaced with natural meat. It was expected that the hungry animal would eat it greedily, but its behavior changed sharply. Instead of eating, a pronounced orienting-exploratory reaction occurred. The dog ran away from the feeder, inspected the experimenter, and only began to eat after some time and with great caution.
A similar mechanism works in the wild. Egyptian vultures break the shells of ostrich eggs using stones brought from the mountains. If, in the bird's absence, a white egg is painted a bright yellow color, the program fails. The image of the egg programmed in the ARA does not match reality: upon returning, the vulture drops the stone, opens its beak, and exhibits an orienting-exploratory reaction without completing the target action.
Information Base of Prediction
The acceptor is constructed from two main information sources:
- Genetic basis. Includes innate knowledge about needs, ways to satisfy them, and the parameters of results that can fulfill these needs.
- Acquired memory. Replenished as one interacts with the external environment.
During the accumulation of individual experience, reinforcing factors affect receptors. Due to reverse afferentation, a detailed informational 'image' of reinforcement is built in the brain (these concepts of animal activity were formulated at the time by I.S. Beritashvili). Subsequently, the triggering stimulus and motivation anticipatorily activate this image, indicating ways to achieve the goal.
It is precisely thanks to such mechanisms that the formation of thought occurs during mental activity — the brain continuously compares achieved results with the forecast and evaluates them.