We know that one idea suggests another, and that volitional movements are the outcome of ideation.
As contrasted with the first it stood for the necessity of recognizing a universal or ideal element as a constitutive factor in all experience whether cognitive or volitional; as contrasted with the latter for the ultimate unity of subject and object, knowledge and reality, and therefore for the denial of the existence of any thing-in-itself for ever outside the range of experience.
The exact relation between the two was, however, a matter of controversy, Aquinas and Duns Scotus holding that both are practical reason, while Bonaventura narrows synderesis to the volitional tendency to good actions.
Coincidently with the persistence of the tonic contraction, the higher and volitional centres seem to lie under a spell of inhibition; their action, which would complete or cut short the posture-spasm, rests in abeyance.
Could we assume that there is in the adult man reflex machinery which is of higher order than the merely spinal, which employs much more complex motor mechanisms than they, and is connected with a much wider range of sense organs; and could we assume that this reflex machinery, although usually associated in its action with memorial and volitional processes, may in certain circumstances be sundered from these latter and unattendant on them - may in fact continue in work when the higher processes are at a standstill - then we might imagine a condition resembling that of the somnambulistic and cataleptic states of hypnotism.