As I have stated in a previous paper,[15] the pathogenesis of tics and
allied conditions can best be appreciated by viewing the subject from an
evolutionary standpoint. In our reactions and adaptations to the varying
experiences with which we meet we respond by one or more of several methods
of motor reaction. These motor expressions are of increasing complexity as
we ascend the scale of evolution and development. One of the simplest kinds
of adaptation is by simple, reflex muscular action, the response being
anatomical and not physiological in its extent. Then come our simple
physiological reactions. A more complex reaction is by those
physiologically co-ordinated motor reactions or movements which go to
comprise our pantomimic movements. This is seen most characteristically in
our facial expressions, gestures, mimicry and dancing. Still higher up in
the scale we find our conduct and feelings as exemplified in our speech. And
finally, highest of all, we must place our conduct as shown in written or
printed language. This is a brief outline of our evolutionary and
developmental ascent and of the increasing complexity and refinement of our
social conduct.
[15] Tics. Interstate Medical Journal, January and February, 1915.
In our motor adaptations we respond in one or more of these ways. When for
some reason or another one outlet us denied us, we find avenues of
expression through one or more of the other paths. Now, the manner and
degree of our response is dependent on our stage in evolution and
development, on the development of our senses, on our instincts, feelings
and emotions, on our intellect and experiences. Unable to find expression by
means of writing or speech, we instinctively fall back upon and seek
expression by a less refined method, one earlier acquired and thus lower in
the scale of evolution. This has a more or less general application
throughout the scale of human (individual and social) conduct. It is an
application of the universal law of adaptation to existing conditions in the
best manner possible under the circumstances. We may thus lay down in a
general sort of way a conception which I like to call the theory of
psychophysical progression, fixation and regression along evolutionary and
developmental lines. In the case of tics the regressive or devolutionary
aspect comes in for special consideration. We may react mainly physically,
or mainly psychically. But as a rule we react by both physical and psychic
means, the manner and degree of our conduct being determined, as above
mentioned, by our stage in evolution and development.
How does all this preliminary and general discussion apply to the problem of
the tics? The relation seems to me to be most intimate and most important.
The tics are methods of response or reaction to certain external irritations
or ideas, this response being the manner of adaptation. The response may be
mainly motor or mainly psychic, most frequently psychomotor. When the source
of irritation and the cause for action is known, our conduct is more
specific and is apt to be less diffuse, less inadequate, less indefinite.
In our reactive adaptations, which, as explained above, are greatly
dependent upon our psychophysical make-up or constitution, we protect
ourselves consciously or more or less unconsciously against disagreeable,
inimicable, unpleasant or irritating environmental factors, physical or
psychical, by bringing into activity certain psychical or physical or
psychophysical reactions or processes. The special defense reactions
brought into the foreground are those which follow the line of least
resistance, due to hereditary or environmental construction, or are those
which were most intensely stimulated or irritated and the most biologically
useful and adaptive at the particular moment or under the special
circumstances. The young child's reactions are preponderately motor, or at
any rate psychomotor and not purely psychic. When there are sources of
irritation or bodily or mental discomfort, there is a more or less general
bodily reaction, psychophysical in nature. When the irritation is definite
and clearly recognized by the child, the local motor response is also apt to
be definite. When, on the other hand, the irritation is but vaguely
perceived and not clearly appreciated or localized, we find that the child
may show a general diffuse reaction, or even, in some cases, a reaction
limited to certain regions as determined by the reaction taking place along
the line of least resistance. This is plainly seen in the conduct of the
physically sick child. Every pediatrician will find ample proof in support
of this statement in his observations of the defensive reactions of the ill
child.
When this irritation along a certain nerve path is oft repeated or quite
constant, we have a consequent repetition of the defensive reaction,
whatever it may be. This performance may be so frequently repeated that the
idea of irritation or mental conflict or the anticipation or the expectation
of a repetition of same may be quite sufficient in itself to arouse this
reaction. It may become so habitual that, even though no such idea be in
the mind, there may be a repetition of the movement whenever the individual
is nervously excited or upset, whenever there is any mental stress, strain
or discomfort. And we may go even further and say that as a result of some
unusual mental struggle, some excessive mental strain, defense or adaptation
is brought about by regression or resort to a tic, this being conditioned by
the fact that for the particular individual under discussion this is the
easiest, most convenient or most immediate form of reactive response. The
discharge is, as is seen, along the line of least resistance. This line of
least resistance is determined by the organic nervous constitution and by
certain life-experiences or habit-formation factors. In some cases the
movement, once initiated, may be continued long after the disappearance or
cessation of the external irritation, because of the sense of relief or
satisfaction or pleasure[*] which is obtained by the performance of the tic.
In many instances the habit has become rather fixed, and, as a relief from
the struggle to do or not to do the movement, and because of fatigue in the
effort to inhibit or control the movement, the individual adopts the path of
least resistance, best for immediate relief from mental struggle; and as a
psychobiological effort at self-preservation and self-gratification, as
immediately as possible and at any cost to be paid in the future, he gives
vent, as it were, to the movement.
[*] This is not, of course, of a sexual nature the Freudian school
notwithstanding.
The psychic symptoms may come on at a later date than the motor symptoms or
simultaneously, although, of course, the early life history, in childhood
and puberty, for example, if we are dealing with an adult, may show, at
least in a certain proportion of cases, that the individual was of a
psychopathic type, perhaps somewhat shut-in or asocial. If the appearance of
the psychical symptoms be simultaneous with that of the physical symptoms,
we can understand at once how, like the motor symptoms, they may be repeated
time and again. In many instances, at least, the psychic symptoms arise
later, being added to the motor symptoms. These later psychic symptoms may
be a direct reaction to the source of irritation, or may be occasioned by
the dissatisfaction at being unable to control the movement in question.
The degree of reaction, its duration and severity, depend upon the
hereditary and developmental make-up of the individual and the severity,
frequency and duration of the irritation, physical or psychical. The psychic
element is particularly apt to vary. The more neuropathic and psychopathic
the make-up the greater is the reaction.
Where mental enfeeblement or mental disorder exist, the severity and
chronicity are apt to be still greater.
There is thus a fixation, or rather a regression or reversion, oft repeated,
to a type of reaction of a very infantile, primitive sort, farther down in
the scale of evolution and development.
This picture may be further complicated by so-called neurasthenic,
psychasthenic, hysterical or other reactions. Naturally one would expect to
find these conditions, especially the more aggravated forms, in individuals
of a neuropathic and psychopathic family strain, and who themselves are
neuropathic or psychopathic or both.
It may be mentioned here, as is clearly appreciated from what has been said
before, that there is an interrelationship between the tics on the one hand
and the symptoms which we discover in the psychoneuroses, psychoses and the
mentally unstable on the other.
In all of these conditions we find a cortical origin for the disturbance,
there is a lack of will power, of inhibition and of control of the lower
centres, there is a nervous and mental instability with a tendency toward
regression or dissociation, and the assumption of more or less independent,
almost automatic activity, this activity being characterized by its almost
(relatively) infantile, primitive, archaic makeup.
Were I to take up any one of the tics as an illustration, this general idea
could be applied very nicely. But I shall not present any illustrative cases
in this paper. I shall leave it to the reader, however, to explain the
genesis and evolution of, for example, facial tics (which are so common)
from this standpoint.
In passing I may say that the tic movements may have a special, individual,
psychological significance. But this is by no means necessarily so.
Frequently, I am inclined to believe usually, these movements result rather
merely because there has been effected a psychobiological reaction,
following the theory of psychophysical-progression, fixation and regression
with involvement of the nervous paths most seriously affected or most easily
disturbed.
In the case of the tics, therefore, it is as if the various tic movements
are being used in reaction to or in adaptation to sources of internal or
external, physical or mental irritation, for the protection, defense or
self-preservation of this or that particular part of the nervous system--as
if the movements which we find in the tics and which are the expressions of
certain engrams, neurograms, mnemes or organic memories, are existing in and
for themselves, except that, in the tics, they are reacting with and for the
psychophysical organism, the organic make-up or personality.
The individual, as a biological unit, is reacting to the particular
situation which presents itself by the tic mechanism.
By granting the phylogenetic, racial significance we also give the basic,
psychophysical meaning of tics in all ticquers.