ABSTRACT
In order that the processes of cerebral activity which constitute memory shall be evolved according to their natural laws, it is necessary that the peripheral regions of the system which collect and transport sensorial impressions. Sensorial excitations, when they are diffused in the plexuses of the sensorium and fix themselves there in a persistent manner, do not usually remain there in the state of vague, uncertain impressions. The connections between the peripheral plexuses and those of the sensorium are so intimate that, so soon as an impression has been produced in the former, their partner central regions immediately enter into unison with them. The solidarity between the peripheral and central regions of the system is so real, that when the former fail, the functionment of the central regions is at the same time interrupted. In the domain of intellectual activity it is still the same force that underlies most of the dynamic operations to which this activity gives birth.
