and shaking the head, squinting and winking, swaying, pouting and
grimacing, scraping the floor, rubbing hands, stroking, patting,
flicking the fingers, wagging, snapping the fingers, muffling,
squinting, picking the face, interlacing the fingers, cracking the
joints, finger plays, biting and nibbling, trotting the leg, sucking
things, etc.

The average number of automatisms per 100 persons Smith found to be in
children 176, in adolescents 110. Swaying is chiefly with children;
playing and drumming with the fingers is more common among
adolescents; the movements of fingers and feet decline little with
age, and those of eyes and forehead increase, which is significant for
the development of attention. Girls excel greatly in swaying, and
also, although less, in finger automatism; and boys lead in movements
of tongue, feet, and hands. Such movements increase, with too much
sitting, intensity of effort, such as to fix attention, and vary with
the nature of the activity willed, but involve few muscles directly
used in a given task. They increase up the kindergarten grades and
fall off rapidly in the primary grades; are greater with tasks
requiring fine and exact movements than with those involving large
movements. Automatisms are often a sign of the difficulty of tasks.
The restlessness that they often express is one of the commonest signs
of fatigue. They are mostly in the accessory muscles, while those of
the fundamental muscles (body, legs, and arms) disappear rapidly with
age; those of eye, brow, and jaw show greatest increase with age, but
their frequency in general declines with growing maturity, although
there is increased frequency of certain specialized contractions,
which indicate the gradual settling of expression in the face.

Often such movements pass over by insensible gradation into the morbid