What is the law of regression?

Théodule Ribot, answered from the texts and cited to the page.

Théodule Ribot answers

The progressive destruction of memory follows a logical order — a law. It advances from the unstable to the stable, from the most recent to the most ancient, from the most complex to the most simple.¹ The new perishes before the old; the complex before the simple.² This is what I call the law of regression, or reversion. The mechanism is physiological.

Recent recollections are lightly impressed upon the nervous elements, rarely repeated, and consequently lacking permanent associations — they represent organization in its feeblest form. The sensorial, instinctive memory, by contrast, has become a permanent and integral part of the organism, representing organization in its most highly developed stage.¹

Between these two extremes the movement of amnesia follows the path of least resistance — that is to say, of least organization. The dissolution runs a precise course. In the most common cases, abolition of recent impressions comes first; in total amnesia, complete loss of memory except in its organic forms; and in the most extreme instances, even those organic forms are compromised.³

In aphasia — the partial dissolution of language memory — the same law governs: forgetfulness begins with proper names, passes to common nouns, then to adjectives and verbs, then to interjections, and lastly to gestures.⁴ One further confirmation deserves mention. If the law holds, then recovery — where it occurs — should retrace the path of dissolution in reverse, the most stable forms returning first.

Louyer-Villermay observed precisely this: when memory is re-established, it follows in its return an inverse order to that observed in its dissolution — concrete facts, adjectives, substantives, proper names.⁵ The law of regression is thus verified from both directions. And the law is not confined to memory alone. In motor psychology the same descent is visible in something as familiar as drunkenness: first the highest inhibitory will fails, then the impulsive will, then the delicate voluntary movements of speech and hand, then the semi-automatic movements of walking, then muscular tonicity, then the reflexes, and finally — if the condition is carried far enough — the automatic movements of respiration and the heart.⁶

Evolution and decay follow opposite courses; dissolution retraces, step by step and in reverse, the very order in which the mind was built.

Sources

1. We thus see that the progressive destruction of memory follows a logical order—a law. It advances progressively from the unstable to the stable. It begins with the most recent recollections, which, lightly impressed upon the nervous elements, rarely repeated and consequently having no permanent associations, represent organization in its feeblest form. It ends with the sensorial, instinctive memory, which, become a permanent and integral part of the organism, represents organization in its most highly developed stage.

   Diseases of Memory

2. We have stated these two facts in the dissolution of memory: the new perishes before the old, the complex before the simple. The law which we have formulated is only the psychological expression of a law of life, and pathology shows in its turn that memory is a biological fact.

   Diseases of Memory

3. First, in all cases, abolition of recent impressions; in periodic amnesia, total suspension of all forms of memory, except those which are semi-organized and organic; in total and temporary amnesia, complete loss of memory, except in its organic forms; in one instance (Macnish) amnesia comprising even organic forms.

   Diseases of Memory

4. In the best-known cases of partial dissolution or aphasia, forgetfulness follows the same course, beginning with proper names, passing to common nouns, then to adjectives and verbs, then to interjections, and lastly to gestures.

   Diseases of Memory

5. Louyer-Villermay remarks that when memory is re-established it follows in its return an inverse order to that observed in its dissolution—concrete facts, adjectives, substantives, proper names.

   Diseases of Memory

6. There is, first, a period of excitement, even of exuberant spirits, which is the very antithesis of reflection… Next, a man can no longer control his tongue… After this, he becomes incapable of any continuous plan or action… Then the most delicate voluntary movements, those of speech and of the hands, cease to be co-ordinated. One degree lower, he loses the semi-automatic movements, those of walking… Still lower, the muscular tonicity is weakened… then the reflex movements are abolished; and finally, if the condition is continued long enough, there is cessation of the automatic movements — those of respiration and of the heart.

   The Psychology of the Emotions