Perseveration is seen in many functions, ranging from the simplest to the most complex. It will be considered here in relation to three functions: (1) the relatively simple motor functions of grasp and posture; (2) a more complex function, speech, and (3) the most complex function of all, mentation. The three functions, though they vary in complexity, show a common pattern and are governed by common principles. A further object of this paper will be to consider some biological aspects of perseveration, as seen especially from the standpoint of delirium.
GRASP AND POSTURE
We can learn much about perseveration by considering the grasp and its relaxation. Is the relaxation of the grasp a merely passive act, wherein the innervation of the "grasp center" somehow just comes to a halt? Or is it an active deed? Observation of infants gives the answer. An infant is clutching a rattle when you dangle
MAX LEVIN. Perseveration at Various Levels of Complexity, with Comments on Delirium. AMA Arch NeurPsych. 1955;73(4):439–444. doi:10.1001/archneurpsyc.1955.02330100071011