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bound to consider what becomes of the known facts when we cease to regard the brain as a storehouse of
memories.[77]
Let us admit, for the moment, in order to simpli-
(165) -fy the argument, that stimuli from without give birth, either in the cortex or in other cerebral centres, If any image-centre
really exists, it is likely
to elementary sensations. In fact, every perception includes a considerable number of such sensations, all
to be a kind of
co-existing and arranged in a determined order. Whence comes this order, and what ensures this co-
keyboard, played upon
existence ? In the case of a present material object, there is no doubt as to the answer : order and co-
by memories, as the
existence come from an organ of sense, receiving the impression of an external object. This organ is
sense-organ is played
constructed precisely with a view to allowing a plurality of simultaneous excitants to impress it in a certain
upon by objects
order and in a certain way, by distributing themselves, all at one time, over selected portions of its surface.
It is like an immense keyboard, on which the external object executes at once its harmony of a thousand
notes, thus calling forth in a definite order, and at a single moment, a great multitude of elementary
sensations corresponding to all the points of the sensory centre that are concerned. Now, suppress the
external object or the organ of sense, or both : the same elementary sensations may be excited, for the same
strings are there, ready to vibrate in the same way ; but where is the keyboard which permits thousands of
them to be struck at once, and so many single notes to Unite in one accord ? In our opinion the ` region of
images,' if it exists, can only be a keyboard of this nature. Certainly it is in no way incon-
(166) -ceivable that a purely psychical cause should directly set in action all the strings concerned. But in
the case of mental hearing-which alone we are considering now-the localization of the function appears
certain, since a definite injury of the temporal lobe abolishes it; and, on the other hand, we have set forth
the reasons which make it impossible for us to admit, or even to conceive, traces of images deposited in
any region of the cerebral substance. Hence only one plausible hypothesis remains, namely, that this region
occupies with regard to the centre of hearing itself the place that is exactly symmetrical with the organ of
sense. It is, in this case, a mental ear.
But then the contradiction we have spoken of disappears. We see, on the one hand, that the auditory image
called back by memory must set in motion the same nervous elements as the first perception, and that
recollection must thus change gradually into perception. And we see also, on the other hand, that the
faculty of recalling to memory complex sounds, such as words, may concern other parts of the nervous
substance than does the faculty of perceiving them. This is why in psychic deafness real hearing survives
mental hearing. The strings are still there, and to the influence of external sounds they vibrate still; it is the
internal keyboard which is lacking.
In other terms, the centres in which the elementary sensations seem to originate may be actu-
(167) -ated, in some sort, from two different sides, from in front and from behind. From the front they
receive impressions sent in by the sense-organs, and consequently by a real object ; from behind they are
subject, through successive intermediaries, to the influence of a virtual object. The centres of images, if
these exist, can only be the organs that are exactly symmetrical with the organs of the senses in reference to
the sensory centres. They are no more the depositories of pure memories, that is, of virtual objects, than the
organs of the senses are depositories of real objects.
We would add that this is but a much abridged version of what may happen in reality. The various sensory
aphasias are sufficient proof that the calling up of an auditory image is not a single act. Between the
intention, which is what we call the pure memory, and the auditory memory-image properly so called,
intermediate memories are commonly intercalated which must first have been realized as memory-images
in more or less distant centres. It is, then, by successive degrees that the idea comes to embody itself in that
particular image which is the verbal image. Thereby mental hearing may depend upon the integrity of the
various centres and of the paths which lead to them. But these complications change nothing at the root of
thins. Whatever be the number and the nature of the intervening processes, we do not go from the
perception
(168) to the idea, but from the idea to the perception ; and the essential process of recognition is not
centripetal, but centrifugal.
Here, indeed, the question arises how stimulation from within can give birth to sensations, either by its
action on the cerebral cortex or on other centres. But it is clear enough that we have here only a convenient
way of expressing ourselves. Pure memories, as they become actual, tend to bring about, within the body,
all the corresponding sensations. But these virtual sensations themselves, in order to become real, must
tend to urge the body to action, and to impress upon it those movements and attitudes of which they are the
habitual antecedent. The modifications in the centres called sensory, modifications which usually precede
movements accomplished or sketched out by the body and of which the normal office is to prepare them
while they begin them, are, then, less the real cause of the sensation than the mark of its power and the
condition of its efficacy. The progress by which the virtual image realizes itself is nothing else than the
series of stages by which this image gradually obtains from the body useful actions or useful attitudes. The
stimulation of the so-called sensory centres is the last of these stages : it is the prelude to a motor reaction,
the beginning of an action in space. In other words, the virtual image evolves towards the virtual sensation,
and the virtual sensation towards real movement: this
(169) movement, in realizing itself, realizes both the sensation of which it might have been the natural
continuation, and the image which has tried to embody itself in the sensation. We must now consider these
virtual' states more carefully, and, penetrating further into the internal mechanism of psychical and psycho-
physical actions, show by what continuous progress the past tends to reconquer, by actualizing itself, the
influence it had lost.
Endnotes
1. Robertson, Reflex Speech (Journal of Mental Science, April, 1888). Cf. the article by Ch. Féré, Le langage réflexe (Revue
Philosophique, Jan. 1896).
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