Memory

MEMORY. - In modern psychology, which seems to continue the conception of decadent Scholasticism, memory generally means the function that preserves the images of the senses or those produced by the imagination. Through memory the past states of consciousness are relived and recognized: it therefore entails the power to preserve, recognize, and localize in time and space the facts and phenomena of consciousness that have been experienced.

It seems an established conclusion that the object of memory must be restricted to representational contents, because feelings and volitions are not repeated but are always actualized in consciousness in an original form. The principal problem of memory then becomes the genesis and reproduction of images: it was therefore investigated whether the actions of stimuli that impress the senses reach as far as the centers, leaving a physical imprint there, and whether there exist special centers in the brain deputed to preserve in isolation the various classes of perceptual objects (the doctrine of "cerebral localizations"). Above all, the laws regulating the reproduction of representation when it is evoked into consciousness were investigated: on this subject the way had been opened by Aristotle himself, who had indicated as factors of reproduction contiguity of space and time, similarity, and dissimilarity (De memoria et reminiscentia, 2, 451 b, 12 ff.: note should be taken of Aristotle's anticipated criticism of Hume's principle, which placed in habit the principal force of the association of ideas). Nevertheless it must be recognized that every theory or attempt at explanation of memory on a biological or physiological basis has so far failed to establish itself: in any case the vast and rigorous researches of positivist psychology (especially those of H. Ebbinghaus) have considerably widened the field of action of memory and our knowledge of the behavior of images. Against the associationist school the Denkpsychologie (Külpe, Ach, Lindworski) reacted indirectly, but above all the Gestaltpsychologie, which maintained that the movement of ideas (v.) or images does not obey the content of the individual elements but is a function of the "structure" (Gestalt) of the "whole" (Ganze): except that this school fell back into a form of physiological materialism by affirming that the cohesive force of structures was a function of the distribution of nervous energy along the system from the peripheral organ to the centers (the Querfunktionen or transverse connecting currents).

The reality is that memory constitutes in man a set of very complicated processes because of the multiplicity of the objects and conducts of human life: in particular, memory is the meeting point of the life of the ego (v.) and therefore of both conscious and subconscious life. H. Höfling had recourse to the "feelings" of familiarity, which convey the conviction of having previously known something: but even the emotional theory, if it explains some phenomena of memory, leaves not a few others in obscurity. Even after the experiments of G. E. Müller, who concluded in favor of the prevalence of feelings (of familiarity), it seems that emotional factors, even if they are usually present, have a secondary part in the processes of memory (Gemelli). A surer path is the one envisaged by Lindworski, for whom the principal element at play in memory is time, so that the phenomena of memory refer back to the experience of spatial and temporal "relations."

This direction leads back in substance to the primitive Aristotelian doctrine of memory and recollection: Aristotle in fact discusses at length the relations between the perception of time and memory, which he orders in two phases: memory properly so called, when the temporal relation operates the recall spontaneously without a precise knowledge of the interval; and "recollection" (v.), which instead sets out in search of the memory on the basis of a well-defined knowledge of time itself (op. cit., 2, 452 b 26-435 b 35). According to St. Thomas, memory is the faculty that preserves the apprehensions of the concrete meaning of things (intentiones individuales) learned from the cogitative power (v.), which is the intermediate function between sensitive and intellectual life (cf. Sum. Theol., 1a, q. 78, a. 4), to which belongs the perception of the concrete relations that things have with life.

Cornelio Fabro

EXPERIMENTAL PSYCHOLOGY AND PEDAGOGY

It seems that first of all it must be observed: 1) that it would be an arbitrary narrowing of the domain of m. to wish to limit it to the properly so-called cognitive field: in fact, feelings and emotions can also be recalled (a pain experienced, a love that has faded); 2) that the proper and direct object of m. is not a thing or a fact exterior to us, but only the perception we have had of the thing or the fact; the emotion provoked by them in us cannot, in fact, "re-present" in our consciousness anything other than what was "present" there before (properly speaking, we do not remember Rome, but that we have seen Rome); we are therefore like intermediaries between m. and the object.

1. The various kinds of m

a) According to the object that we more easily retain or according to preferences or acquired or innate predeterminations, there is the m. of dates, of languages, of numbers, of names, of genealogies, etc.; b) According to the cognitive nature of the memories there is: α) sensitive or sensory m., if it concerns sensory images, which is subdivided into: visual m., when one is more struck by forms and colors (painters, draughtsmen, chess players, who conduct several games simultaneously without ever lowering their eyes to the various chessboards); auditory m., when it preferably retains the sounds of music or of the rhythmic language of poetry or of simple words (psittacism); muscular or motor m., when it above all retains the memory of the movements of the lips in pronouncing letters, syllables and words, or of the fingers for playing or of the legs and feet for skating, dancing, etc.; tactile m., like that of the blind who read books and musical scores by running the tips of their fingers over the text. β) intellectual m., which remembers ideas, judgments, reasonings; γ) affective m., which remembers emotions and volitions.

Sensitive m. also belongs to animals, as experience abundantly proves; in man it is conjoined and also integrated by intellectual m. Man, for example, does not remember only the sound of the words of a speech or the exact placement of the words in a verse, but also the sense of that speech and of that verse.

2. Analysis of the mnemonic phenomenon

The elements or processes that mutually integrate in an act of m. can be reduced to five: fixation and conservation (m. of fixation); recall (m. of reviviscence); recognition (m. of reproduction); localization (chronological m.).

a) Fixation of the concept or of the image. — Physiologically m. depends on the functionality and plasticity of the nervous tissues; which vary to an extreme degree from person to person, and, in the same person, according to age, state of health, occupations, bad habits contracted; and they range from a degree of extraordinary power of fixation to a null or nearly null degree. Psychologically the degree of fixation is proportioned to attention, to the presence of centers of interest, to exercise. Therefore a memory is fixed all the more, the more a fact has made an impression (a battle, an earthquake, an exceptional ceremony are not easily forgotten). Likewise the relation of m. to innate or acquired tendencies favors fixation (a lazy person quickly forgets the teacher's explanation, while he remembers very well the various soccer matches or the names of the competitors in races) or to the content of consciousness (one who is intensely absorbed in his own reflections or in the carrying out of some undertaking lets a great quantity of memories and experiences slip away). Finally the degree of fixation depends on the law of use and non-use; exercise does not create the memory, but strengthens it, prevents it from disappearing, bringing into play the mechanism of repetition and association. What has been seen only once or learned hastily is easily forgotten, while what has been read or seen or heard several times or studied calmly is better remembered. Sensations, then, images and ideas, which are easily lost if isolated, are on the contrary remembered quite well if gathered into groups or associative syntheses. Thus, in order not to forget an errand, one spontaneously ties a knot in one's handkerchief; by means of mnemonic verses one easily retains dates, geographical names, rules of grammar or of logic; as likewise by means of words constructed from the initial syllables of a determined group to be remembered or by the drawing up of ordered lists.

b) Conservation of memories. — The re-emergence of past experiences poses the problem of how they are conserved in m. In this process the same thing happens as in habits which, exercised in a determined sense, tend to reproduce the same acts. Thus in memories, the acts that form their content disappear, but leave a physio-psychological disposition to be repeated. Therefore conservation of memories means nothing other than the possibility of recalling them; a psychophysiological disposition to reproduce them, which passes into act when the suitable conditions come to be verified.

c) Recall of memories. — It is the passage of m. in potency to m. in act and consists, physiologically, in restoring, so to speak, the primitive organic state and, psychologically, in leaving or bringing into play the laws of the various kinds of association. Recall can be spontaneous, when the memory arises abruptly without any apparent physio-psychological link with the present state of our consciousness (reviviscence); voluntary, when the memory is deliberately evoked or more or less laboriously sought (reminiscence). The will, however, has no direct power over memory (it is commonly said: "it is enough that I search for it not to find it"; "I have the word on the tip of my tongue; I will remember it when I no longer think about it"), it cannot initiate the recall of an idea in its completeness; what it can do is provoke those associations that can set one on the path and in the direction of what one wishes to find. Thus to recall a proper name one thinks of how it begins or how it ends; one keeps the initial or final syllables fixed before the mind and the sought-for name will end up reappearing. The insistence of the will often harms the free play of associations; therefore it is better to leave free course to the nervous current so that it directs itself spontaneously toward the sought-for object. For this reason the best way to write a word orthographically well, whose spelling escapes us at that determined moment, is to let the pen run freely; if at a certain point the continuation of a poem or of a prayer escapes us, the best means is to start again from the beginning and let the lips move, so to speak, automatically; for this reason too one closes one's eyes when one wishes to recall a memory, one goes into the dark, one makes silence around oneself, because the more the spirit is at rest and the less distracted by present perceptions, the better the various associations function freely and the more it is fit to recall the past.

d) Recognition. — It is the "knowing again" a past experience in a present one; the comparing of the present experience with the past one. The process unfolds in two successive phases: simple sensation of the "already seen or already heard," etc., without any evocation of the past: "that man I have already seen"; "that music I have already heard"; then, by means of the automatic provocation upon the past, a search for the complete and determined ancient experience, that is, a search for the ancient experience that is entirely similar to the present one; "there: it is Peter"; "it is such and such a passage of La Traviata." Here there is true complete recognition.

e) Localization of the memory. — More than a distinct function of memory, localization is the complement of recognition and consists in determining at what moment the remembered fact occurred. Its process is regressive; one goes back along the line of lived time. For an exact localization it helps to establish something like a series of milestones or points of reference, tied to the most important facts and events of our life, to which we bind all the other memories by means of association (e.g., the various stages of schooling: middle school, high school, university; the stages of a career, etc.).

3) Diseases of memory. — The disturbances that can affect memory are divided into quantitative (amnesia, hypomnesia, hypermnesia) and qualitative (dysmnesia, paramnesia).

a) Quantitative disturbances. — α) Amnesia is the total or partial loss of the capacity to fix or to recall memories duly registered at the proper time. Total amnesia in a definitive form is rare; nevertheless there are cases of change of personality (the subject begins an entirely new life without any interference from the past life); cases of very severe dementia and of grave clouding of consciousness. More frequent is amnesia in temporary form, following violent impressions (shock) and certain cerebral concussions. One may also find a periodic amnesia, in the case, e.g., of alternating personalities, where there is also an alternation of memories.

Amnesia is also distinguished as: anterograde (or of fixation), retrograde (or of recall), anteroretrograde or mixed, lacunar: 1) anterograde, when the capacity to fix new memories is lost starting from the moment a pathological state occurs (e.g., the subject remembers everything up to the moment of the lesion; of what happened afterward, until the moment he recovers, he remembers nothing). It generally occurs through clouding of the sensory apparatus, through senile dementia or even in normal old age (the subject no longer remembers a sentence just read, while he remembers whole passages read in his youth); 2) retrograde, when there is loss of memories duly registered, which starting from a determined moment one can no longer, or only with difficulty and effort, recall and associate; this generally occurs following cerebral traumas, or severe intoxications or certain cerebral infections; 3) anteroretrograde, when there is loss of memories anterior or posterior to the moment of the incident that occurred; the subject remains so disoriented that he can neither fix new memories nor recall old ones. It takes place in severe dementias and in states of grave clouding of consciousness; 4) lacunar, when the capacity to fix all or a group of perceptions becomes for some time null or very weakened. β) Hypomnesia is the progressive weakening of memory and is an effect of mental illness and generally parallel to the weakening of intelligence. γ) Hypermnesia is the exaltation of the capacity for recall with the awakening of memories buried for a long time in the past. It occurs, e.g., in those who find themselves in very grave and imminent danger of life (e.g., in executed criminals, who in an instant remember the whole course of their life) or in situations rich in emotions (e.g., in examinees, who, excited by the environment and the circumstances, answer more than they thought they knew); in manic or obsessive states, during fever or hypnosis (memories crowd in, speech is exalted and becomes precipitate). One should also note a form of pseudo-hypermnesia, or facility of recall for a determined group of images or ideas; e.g., in delusions of persecution, or in obsessions, in which a whole crowd of neighboring representations accumulates, which reinforce those proper to the delusion.

b) Qualitative disturbances. - α) Dysmnesia (a form of amnesia of recall) is the difficulty of remembering at a given moment certain representations, which later return spontaneously. It appears in more or less severe forms in psychic and intellectual impairments; or they are provoked simply by excesses of fatigue, by illness or by old age. Hence, e.g., the tiresome repetition of facts on the part of persons who no longer remember having already told them. β) Paramnesia is a false memory due to illusions of recognition. Such illusions sometimes vitiate the perception of the fact (two witnesses, e.g., do not always see exactly the same fact from the same angle) or the preservation of the memory and the successive recalls (the same person reports the same fact differently at different times) or the very expression and reference of the fact (circumstances are added and colored both by the autosuggestion of the subject who recounts and by the suggestion of the environment and of the listener). Hence the necessity and at the same time the difficulty of a valid critique of one's own introspection and of the testimonies one brings. Characteristic too are the illusions of the "already seen," provoked by experiences which, instead, were never realized, or of the "not seen," provoked by experiences which, instead, were already realized. These paramnesias, if conscious, can also generate grave or profound psychological disturbances, to the point of terror and madness.

4. Pedagogy of memory

From the study of the problems of memory and of the procedures of memorization, experimental psychology, especially through the work of A. Binet and H. Ebbinghaus, has been able to derive various norms of high pedagogical value for the education of memory: 1) studying by memory, daily, when it avoids excesses, is very useful, constituting an excellent gymnastics for making memory ready and lively, accustoming one to personal work, causing one to avoid the "approximately" in knowledge. 2) For a good memorization one should choose the times of greatest cerebral freshness: childhood and youth with regard to life; morning, with regard to the day. 3) Alternate the exercises (a quarter of an hour, half an hour, then a little rest). Hasty and spasmodic memorization does not give time for the notions to fix themselves well; evening lessons are remembered more easily, because the rest of the night follows. 4) Proceed from the easy to the difficult, from the little to the much within the same span of time, in order to favor training. 5) Apply the means of developing memory: describe an object, then repeat aloud its written description; fix a series of names with their meaning, then repeat them; draw up the list of the objects of a room, with their names; have many verses studied, which are easier to retain by way of rhythm and rhyme. 6) Apply attention, so that the experience produces a more vivid impression. 7) Encourage the study of foreign languages; studying one is equivalent to exercising memory in four directions: eye, ear, larynx, hand, besides the exercise of intelligence. 8) Prefer the "global" method to the "fragmentary" method. A passage is retained and remembered sooner by studying and repeating it all at once, without interrupting the succession of words and sentences, than by studying it in periods and then associating them together.

Celestino Testore