ABSTRACT
The contingent of sensitive elements specially reserved for distribution in the field of psychical activity, as we have defined it, is represented by all those agglomerations of sensitive excitations which, drawn from all the sensitive points of the organism, are conducted towards the central regions by the centripetal channels. Sensitive impressions in general comprehend merely impressions of touch, contact, and pressure of bodies, but also those which give us the idea of temperature, and that of the activity of our muscles. The luminous vibrations, directly transformed into nervous vibrations by the peculiar action of the retina, are all at first concentrated in the grey centres of the optic thalamus devoted to them, and radiated thence, chiefly into the antero-lateral regions of the cerebral cortex. Like all the sensorial impressions, the excitations of physical pleasure affect both the sphere of psychical activity and that of intellectual activity proper.
