excitation of the sensory centre in accordance with the form of the
incoming stimulation and the central reaction involved in the
recognition of the sensation, are incomplete. These are so limited and
comparatively unimportant a class, that it will be well to dispose of
them at once.


_Confusion of the Sense-Impression._

The most interesting case of such an error is where the impression is
unfamiliar and novel in character. I have already remarked that in the
mental life of the adult perfectly new sensations never occur. At the
same time, comparatively novel impressions sometimes arise. Parts of the
sensitive surface of the body which rarely undergo stimulation are
sometimes acted on, and at other times they receive partially new modes
of stimulation. In such cases it is plain that the process of classing
the sensation or recognizing it is not completed. It is found that
whenever this happens there is a tendency to exaggerate the intensity of
the sensation. The very fact of unfamiliarity seems to give to the
sensation a certain exciting character. As something new and strange, it
for the instant slightly agitates and discomposes the mind. Being unable
to classify it with its like, we naturally magnify its intensity, and
so tend to ascribe it to a disproportionately large cause.

For instance, a light bandage worn about the body at a part usually free
from pressure is liable to be conceived as a weighty mass. The odd sense
of a big cavity in the mouth, which we experience just after the loss of
a tooth, is probably another illustration of this principle. And a third
example may also be supplied from the recollection of the dentist's
patient, namely, the absurd imagination which he tends to form as to