One of the most important relationships between an organism and its environment are the so-called associative reflexes, with which we have already met in part in the previous presentation.
By the name of associative reflexes, we mean that numerous series of reactions that, unlike simple reflex reactions, are not directly and directly dependent on external stimulation, but are caused by the revival of one of the previous traces, due to the established combination between the given external impression and the former impression that left well-known trace. 216
Thus, in this case, although the external reaction develops under the influence of a certain external cause, it does not depend on the given external influence: it is the result of past influences, being determined by the combination of the traces of these influences with the given impression. An example of these reactions can be such movements as running away at the sight of a wild animal, moving away at the sight of a gun, tilting the head when hearing the whistle of a bullet, etc.
In all the examples cited, we are talking about such movements, which, being machine-like in nature, like simple reflexes, in their development initially depended on past influences that excited reflex movements and left traces with which extraneous external stimuli were closely combined, exciting, thanks to a combination of similar or reflex movements.
Developing in life under the influence of external influences coinciding in time with stimuli that excite ordinary reflexes, these movements can be called natural associative reflexes. Obviously, for the implementation of such associative reflexes, the presence of a ready-made mechanism is necessary, capable of performing ordinary reflex movements, and this mechanism is brought into action here through unusual stimuli that do not initially excite ordinary reflexes of this kind, but cause them only due to their repeated coincidence. with stimuli that evoke ordinary reflexes.
In contrast to ordinary reflexes, experience has shown that such associative reflexes exhibit a tendency to fade away upon repetition. Everyone, for example, knows how quickly a person on the battlefield gets used to the whistle of bullets and stops responding to it.
Let’s take another example to clarify what has been said. Let us suppose that a person was frightened by a shot from a gun, which was expressed by reflex defensive movements. This is enough for him to continue to display a defensive reflex at the sight of any gun in general, even if it is not even loaded. But over time, when he takes a closer look at the gun, the associative reflex, previously evoked by one type of gun, already disappears, but it will appear every time he sees a loaded gun.
From what has been said, it is clear that the combination reflex, which initially develops in the form of a general reflex, gradually differentiates into an association reflex, which is found only under strictly defined conditions. On the other hand, if the same person is suddenly frightened by a shot from a revolver, he will not show the above combination reflex. at the sight of a loaded gun alone, but also at the sight of a loaded revolver.
The most important feature of the combination reflex is its revival with each new stimulus coinciding with the stimulus that excites the main reflex, the repetition of which it represents. Let us suppose that a person, under the influence of a dog attack once happened, is removed from all dogs in general already at one meeting with them. But with more frequent handling of dogs, he can easily get used to them, as a result of which he ceases to detect associative-reflex defensive movements when he meets them, but it is enough that the former dog bites him on any occasion for the associative defensive reflex to revive again, moreover it will manifest itself only in relation to this dog. Thus, here, too, the initially general associative reflex gradually faded away, but then, as a result of a new stimulation, revived again, becoming differentiated.
Let us now assume that a person was bitten by another, and then by a third dog; in this case, he begins to move away from all dogs again.
Thus, here the associative reflex, which has become differentiated, is again generalized, spreading to other stimuli that are in the same ratio with the initial stimulus (Bekhterev V. L /. The value of the study of the motor sphere for an objective study of the neuropsychic sphere of a person / / Russian doctor * 1909 No. 33. C. P05-1109; No. 35. C 1174-1176; No. 36. C, 1199-1203). From the following example, it is also easy to see both the extinction or inhibition of the associative reflex and its revival.
Imagine that we are in a museum and see before us large poisonous snakes hidden behind glass. We calmly and with interest consider them. But let us suppose that the embittered snake has rushed to the glass and the frightened spectator cannot refrain from jumping back. However, you can get used to this, after which throwing the snake to the glass no longer causes the same effect. Suppose, then, that one of these snakes is set free. It is easy to imagine with what swiftness a person will bounce off it at one approach of a snake to him.
From the examples cited, we are convinced that natural associative reflexes are subject, on the one hand, to differentiation and generalization, and on the other, to excitation, inhibition and elimination of inhibition or disinhibition.
Experience shows that associative reflexes can be brought up artificially in laboratory conditions, which makes it possible to study all their features in a more complete way. , Bronn, Platonova, etc.), a method was developed for educating combination motor reflexes and the reflexes themselves were studied comprehensively, both in animals (dogs) and in humans. In addition, in a number of works by IP Pavlov, the development and characteristics of the so-called conditioned reflexes to salivation were studied. Unfortunately, the methodology for studying these reflexes is applicable almost exclusively to animals.
The conditions of the experiments in the study of associative motor reflexes are as follows.
Let us assume that the study is conducted with the education of associative motor reflexes to light stimuli, in which case the person under study is placed in a dark room; in front of him is a round window of frosted glass, which is illuminated from the outside by the light of incandescent electric bulbs, which penetrated through colored glasses arranged in a special rotating device at the request of the researcher … (Dr. Molotkov). At the same time, the number of candles in the bulbs for each of the colors was taken according to the calculation of the absorption of light by colored glasses, which was previously determined photometrically in such a way that each color has the same light intensity for the eyes of the person under study* against a frosted glass window and light these colored bulbs at one time or another at the request of the experimenter.
In this way, the elimination of differences in the intensity of light under the action of different colors on the retina, which is possible under the conditions of the experiment, is achieved in this way.
As for the influence of the intensity of illumination, its regulation was achieved under the same conditions of the experiment by the noiseless behavior of incandescent bulbs with one or another number of candles behind the same window with frosted glass.
It is noteworthy that, under the above conditions of the experiment, the movements of the colored shadow in the field of vision, which in itself could evoke a combination reflex, were completely eliminated.
In the form of the main irritation that excites the ordinary reflex in our laboratory, electric current stimulation of the sole of the foot is used, which is achieved by a special device.
The experiments themselves are carried out in such a way that, imperceptibly from the patient, simultaneous stimulation of the sole of the foot by an electric current is given, which causes an ordinary reflex of withdrawing the foot and extending the toes, and this or that light or color irritation of the retina of the eye. or colored stimuli, a defensive reflex, expressed by pulling back the foot and extensor movement of the toes, which will present us with an artificially educated combination reflex to visual (light or color) stimuli.
If, under the same experimental conditions, instead of light or color stimuli, we use sound stimuli, for example, with the tones of the Arrip apparatus, we combine them, as in the previous cases, with electrical stimulation of the sole of the foot, we get an artificial combination reflex to sound stimuli. By combining tactile stimuli of the skin surface with electrical stimulation of the sole of the foot, we get an artificial associative reflex to tactile stimuli. When olfactory stimuli are combined with electric plantar stimulation, we will have an association reflex to olfactory stimuli, and, finally, when taste stimuli are combined with electric stimulation of the sole of the foot, we will get a combination reflex to taste stimuli.
Experience shows that combination reactions can easily be artificially trained in animals as well.
The entire training of dogs and other animals is based on the strengthening of the combinational connection between a given stimulus and a motor reaction, as a result of which the latter is a complex combinational reaction. Such a combined reaction can be in a dog a simple paw on the outstretched hand, the vertical noaa of the animal at the word “serve”, or well-known dog dances, or throwing the dog on pieces of food with the well-known exclamation “pil” and stopping it at the word “tsits”.
As is known, Goltz drew attention to the fact that dogs with the removal of a vast anterior region of the hemispheres lose the ability they acquired with the help of training to apply the paw to the hand. My experiments have shown that this reflex, as well as the ability of dogs to walk on their hind legs, acquired through training, are permanently lost after the removal of some cortical motor centers on the opposite side, which proves the role of these centers in relation to the mentioned reflexes (Bekhterev V. L /. The value of the study of the motor sphere for an objective study of the neuropsychic sphere of a person // Russian doctor * 1909. No. 33. P. P05-1109; No. 35. C 1174-1176; No. 36. C, 1199-1203).
Later, Franz used trained movements in animals to study the function of the frontal lobes, and more recently O. Kalischer (Kaliscker O. Zur Function des SchJafenlappens des Grosshirns // SiLzb, it. Kotiigl, Academic der Wissensch, Sitz. d. phys.-math Classe-Berlin, 1907. Bd. 31,) used the training of dogs to study the subtlety of their hearing, as well as to clarify the role of conductors and cortical centers. Through repeated exercises he achieved that he trained the dogs to seize pieces of meat at a certain tone, which he calls Frees ton, and to refrain from another tone, which he calls Gegen-ton.
It turned out that Fresston worked even when it was combined with a lot of other sounds and when even musical people could not distinguish Fresston.
In the same way, it was possible to train a dog to grab pieces of meat only by immersing its paw in warm water or by bending its front paw, etc.
The disadvantage of this method lies in the fact that it requires preliminary training, which depends largely on the skill of the experimenter.
In the meantime, our experiments have shown that the development of the associative motor reflex in animals can be carried out according to the same principle as in humans. Thus, for example, associative reflexes can be artificially cultivated in the sphere of respiration, as our experiments on dogs convince us of.
For this purpose, a pneumograph arranged by me, which makes it possible to record the movements of breathing on a rotating drum, is adapted to the dog in the stand. If we take a sound stimulus of known intensity, such as a gunshot, we will see that the breath produces a deep inspiratory sigh followed by some subsequent inspirations. Then, with this basic stimulus, we can combine any other stimulus that does not in itself affect breathing, such as moderate light. If this combined stimulation is produced a certain number of times simultaneously with the shot, then we will eventually get inspiratory respiratory movements and one stimulation with light.
This effect, however, gradually fades away after several stimulations with one light; but after a new combined stimulation with sound and light, the latter again gives the same inspiratory effect on respiration, and a similar revival of the reaction of la and light can be produced any number of times,
In this case, we obtain in this way an artificially induced combination reflex to light (in humans, these phenomena with a combination respiratory reaction were obtained in our country by Dr. V, Ya. Aafmovshs).
In a similar way, we can induce a combination response to breathing with electrocutaneous irradiation. For this purpose, we will take a skin irritation with an electric current, which constantly causes excitation of respiration, and simultaneously with it we will produce, for example, a certain tone, which does not in itself cause a reaction to respiration, but after several combinations of such stimuli we will get a reaction to respiration already for one tone.
Similarly, in dogs it is not difficult to evoke an associative reflex from the limbs. For this purpose, stimulation with an electric current of such strength as to cause an ordinary reflex from the side of the limb is applied to one * of the paws of the animal simultaneously with one or another extraneous stimulus (for example, sound, light, etc.) that does not excite a motor reflex, and already after several times-
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stimuli, it is possible to obtain an associative reflex in the form of withdrawal of the paw to this new stimulus, whether it be sound, light or any other.
From our studies cited above, it turned out, among other things, that if we take the dog as the main electrical stimulation, then it is relatively easy to evoke in it a combination of sound and cold reactions to breathing, while a light combination reaction is formed with much more difficulty.
From this it is clear that some associative reflexes develop more easily, others more difficult. .
Associative reflexes are formed especially easily and, apparently, are more durable with stimuli that are in close proportion to each other, for example, stimulation by touch and electrical skin stimulation.
There is no need here to go into details of the results of research on combinational reflexes. But we will briefly dwell only on those features of the associative motor reflex that were studied in the above studies. At the same time, we restrict ourselves to only the most general properties of associative reflexes, which were partly set forth already in one of my previous works.
Whatever the nature of the combination reflex we have artificially brought up, it will have properties more or less the same for other combination reflexes, and the differences will not be found in essence, but will concern only the quantitative relations of the manifestation of combination reflexes.
As already mentioned above, the development of the associative motor reflex occurs in different cases with unequal ease, which depends to a large extent and primarily on the nature of the associative stimulation (tactile, sound, visual, etc.).
It must be borne in mind that the appearance of the associative reflex in all cases corresponds to the moment of the beginning of the associative stimulation, and not to the moment of action of the main irritation, resp. electric current — a feature that indicates that the combination reflex *, although it is caused by combining one or another irritation with the main skin-electric, but at that time it is also independent of the latter, due to the actual revival of its trace during the onset combination irritation.
Let us assume that we apply light stimulation for a certain period of time, and the electric current will be applied only in the middle of the action of light stimulation. When an associative reflex to light stimulation is developed, it will always appear at the beginning of the action of light, and not in the middle of it, corresponding to the time of action of the electric current. Even if an associative stimulus, for example, a sound one, precedes the main electrical stimulation, the educated associative reflex will occur at the moment of action of light, and not at the moment of action of current.
Further, as investigations carried out in our laboratory show, any associative reflex in general from the very beginning appears to be more or less general, i.e., it is found indifferently to this or that stimulus, but already in the period of education it is differentiated in the sense that if he was brought up for a certain stimulation, for example, visual, then he is not excited by any other to the characteristic
Bekhterev V, M. The significance of the study of the motor sphere for an objective study of the neuropsychic sphere of a person.
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ru irritation, for example, sound or olfactory, and vice versa. But, on the other hand, the associative reflex that has developed, as studies in our laboratory have shown, initially, within the limits of a certain kind of stimuli, appears more and less general and undifferentiated, since it is found during various stimuli of the same kind, with which an external stimulus that causes it is combined. . But over time, with further experiments, a strictly differentiated associative reflex is gradually brought up.
At the same time, it is not difficult to make sure that any combination reflex, initially an undifferentiated reflex, only gradually, through education, becomes more or less strictly differentiated. So, if in the above way we get a combination reflex to a certain tone of a given instrument, for example, an Arrshptian apparatus, then it turns out that initially any tone of a given instrument will evoke the same reflex. In general, the associative motor reflex initially appears in the same way even with the most diverse tones of different timbres. If you work out the same reflex to a certain color (Dr. Walker), then it will initially be called up to any other color, etc. But if in the future we repeat the reflex to a certain type of stimulation, strengthen it by a new combination with electrical stimulation , then it gradually differentiates itself under the influence of the exercise; on the other hand, if we repeat the reflexes to other stimuli and thus tire them out by supporting them with a combination with an electrical stimulus, as a result of which the reflexes to these stimuli will weaken and, finally, will be completely inhibited, then in this way we will accelerate the development of a differentiated combination reflex, which will always appear only for a given specific kind of irritation.
When educating a differentiated association reflex, a well-known regularity is revealed, which in relation to sounds is expressed by the fact that tones of a different timbre than the main tone cease to cause an association motor reflex earlier than tones of the same timbre, but of a different height than the main tone for which it was brought up associative reflex (Dr. Protopopov).
Further, when cultivating the associative motor reflex, it is not difficult to be convinced of the significance of the process that we designate by the name of induction. So, if a dog develops an associative motor reflex to a certain tone, then it turns out that if, after the inhibition of the reflex, by repeated irritation with those or other extraneous tones without current support, then take some top that is close to the main irritation, then the animal initially gives an associative reflex to a sound close to the main tone, to which the reflex was brought up. But if the dog is then given the main tone, then the reflex to close tones does not work; in the same way, if after the reflex to extraneous tones is inhibited and I then immediately give the main tone, then the dog will no longer respond to tones close to it (V. FL Proto-iopov).
The subtlety of differentiation in relation to stimuli depending on their quality seems to be, generally speaking, not the same. According to Protopopov’s experiments, the differentiation of the associative motor reflex in dogs to sound is very fine, reaching 1/7 of a tone.
In organs that have a receptive surface, such as the skin surface, the localization of the stimulus that excites the combination reflex does not go beyond known, always defined boundaries, due to which areas of definite size can be marked on the skin, from which, once brought up, the combination reflex can be received and beyond which this reflex is no longer obtained (Israelson),
There is reason to think that the initial non-differentiation of the reflex is in relation to the general qualities of the stimulus (for example, in tones — timbre, in colors — the total light energy, etc.), but over time, due to the repetition of irritation, the reflex is inhibited in relation to the general element in irritation in view of its constant repetition and the preservation of a reflex in relation to particular features of irritation (Protopopov). In the same way, the associative motor reflex is differentiated earlier in relation to the quality of the stimulus, and then in relation to its intensity.
However, if from the very beginning we educate the combination reflex simultaneously to stimuli of different quality, i.e., we combine successively different stimuli of different quality, for example, different tones or colors with skin-electrical irritation, then the combination reflex will remain general and its differentiation will not follow. .
All studies carried out according to the method of the combination motor reflex speak in favor of the fact that this reflex, once brought up with repeated repetition, gradually weakens and, finally, disappears completely, but it can be revived again when the combination with the main stimulus is resumed, with more with frequent repetition of combinations of an electric current with a given stimulus, the combination reflex becomes more and more durable and, in the end, can be detected a significant number of times without the support of an electric current.
In this regard, apparently, not only the number of combinations matters, but also the quality of the stimulus to which the combination motor reflex is brought up, as well as the conditions of the combination itself.
Thus, to stimulation by touch in a dog (Dr. Israelson), the reflex according to the above method is brought up relatively quickly and becomes so strong that it can be evoked several dozen times in a row without support by a new combination with the main irritation, while to irritations with flowers in a dog the same the reflex itself (Dr. Walker) for its education requires a much larger number of combinations, it is not differentiated so quickly and weakens relatively quickly.
But in general, any combination reflex, when it is repeated without a simultaneous resumption of the main, i.e., skin-electrical stimulation, gradually weakens and, finally, disappears completely, but it revives again when the same stimulation is combined with the main skin-electric. Thus, here we encounter phenomena of excitation or revival of the combination reflex and its inhibition, which can be natural if it does not depend on any external conditions, and artificial if it is caused by external extraneous stimuli.
All these phenomena, as experience shows, express everywhere and everywhere a complete regularity. As for the natural extinction or inhibition of the associative reflex, here there is a strict gradualness in the sense of weakening the strength of the reflex until it disappears completely, if all extraneous irritations are excluded and if the reflex is evoked at certain regular intervals. But if the intervals for evoking the reflex are not the same and one or another extraneous stimulus acts simultaneously, then the correct extinction of the associative motor reflex is more or less significantly violated (A. G. Molotkov). It is noteworthy that the natural inhibition of associative reflexes is characterized not only by a weakening of their strength, but sometimes by their delay, while in organs with a larger perceiving surface, as in the skin, the extinction of the reflex is also characterized by an expansion of the area from which it is called (Ieraelson ). These or other simultaneously acting external stimuli of a different nature also lead to inhibition of the combination reflex. Stronger external stimuli have a particularly sharp inhibitory effect.
If, however, the same extraneous stimulus is applied repeatedly, then it gradually exhibits a weaker and weaker inhibition and, finally, its inhibitory effect completely ceases and sometimes even passes into an exciting effect. It should be borne in mind that both weak external stimuli, as well as inhibitory influences that have lost their strength, can acquire the significance of strong inhibitors through special education, if we combine them with weakening associative reflexes.
The influences stimulating associational reflexes include, first of all, the resumption of the main stimulus, which, as mentioned, always revives the associational reflex, even after its disappearance. Exactly in the same way, the lengthening of the interval through which the combination reflex is evoked, for example, doubled or tripled, and also, under certain conditions, also extraneous external stimuli, acts in an exciting way.
We have already mentioned above that if the time for evoking the reflex is the same, then the reflex will slow down gradually and correctly, but if, for example, the time for evoking the reflex during the period of its natural inhibition doubles even after the reflex has already ceased, then the reflex comes to life again with a certain by force. After its new extinction, a further increase in the time interval revives the reflex again (Dr. Molotkov). Finally, with any increase in stimuli that have already ceased to excite the combination reflex, or with the simultaneous action of a new non-depressing stimulus, the former stimulus, which has already ceased to excite the reflex, again becomes active.
We consider it superfluous here to go into the details of these phenomena, characterized by the weakening or cessation of inhibitory influences or disinhibition processes. causes a combination reflex, we can develop a reflex to this new stimulus without resorting to the action of the main stimulus. In this way we will obtain a «secondary» associative reflex, and in exactly the same way, as our experiments show (Israelson), there can be a receiver and a tertiary associative reflex.
Thus, once an educated combination reflex under certain conditions leads to the development of other combination reflexes, which develop on the basis of the originally educated combination reflex without the use of the main irritation.
Further, research carried out in our laboratory showed that initially, during the period of education, the associative motor reflex is expressed by a more or less general movement, but with the passage of time it becomes more and more a local reflex in terms of the size of the movement itself. So, if initially the animal reacted to the associative stimulus with general movements and voice and a corresponding change in breathing along with the movement of the paws, then over time the associative reflex is more and more limited and eventually becomes local, expressed mainly by a change in breathing and movement of one paw. , on the stimulation of which this combination motor reflex was brought up.
Over time, even respiratory changes may disappear and only one movement of the paw remains, which expresses the associative motor reflex; in other words, from the original general, the associative motor reflex gradually becomes more and more localized and local. But the new support of the associative reflex usually causes a temporary generalization of the associative reflex, which, however, is quickly again limited to the level of a local reflex.
It is noteworthy that if we cultivate a reflex to a complex stimulus consisting of two simultaneous stimuli, then the reflex formed to both simultaneous stimuli usually turns out to be valid in relation to each of the compound stimuli. So, if we cultivate a combination motor reflex simultaneously to light and sound, then separately both light and sound for the most part cause the same reflex. If by repeated stimulation we inhibit the reflex to sound, then at the same time the reflex to light will also be inhibited; if we slow down the reflex to light, then the reflex to sound will also disappear, and at the same time the reflex to the compound stimulus will also disappear. If the reflex, under the influence of certain conditions, is again animated to a compound irritation, then it is often animated in relation to each of the components of the irritation.
In a word, the phenomena observed in relation to a reflex to one of the constituent parts of the stimulus are, to one degree or another, significant in relation to the reflex to another component of the stimulus, and vice versa — a reflex brought up to a component stimulus usually has a meaning both in terms of in relation to the individual parts of this irritation (Dr. Broni).
It must be borne in mind, however, that under these conditions there may be a predominance of one compound stimulus over another in the sense that the associative reflex to it is retained longer than to the other, or even a reflex to one stimulus, taken separately, is evoked, while not called for another (Dr. Platonov). These cases depend on the strength, quality and greater or lesser proximity to the main stimulus and other conditions related to individual stimuli.