Hoffmann reflex variations produced by task demand characteristics.
It has been shown that monosynaptic reflexes could be facilitated or inhibited during tasks differing in nature. The amplitude of the Hoffmann reflex (H reflex) and heart rate have been studied during the performance of two versions of a mental task and a tracking task varying in degree of difficulty. Modification of the H reflex does not depend upon the nature of the task. A slight increase in cardiac rhythm and a facilitation of H reflex during easy tasks and a marked increase in cardiac rhythm associated with inhibition of H reflex during difficult tasks were observed. The increase in H reflex would be due to an activation of the reticular formation. The inhibition of motor response can be attributed to an effortful process which develops when the tasks become difficult.
D000328:Adult; D001143:Arousal; D001288:Attention; D005260:Female; D006181:H-Reflex; D006339:Heart Rate; D006801:Humans; D008297:Male; D009433:Neural Inhibition; D011340:Problem Solving; D011597:Psychomotor Performance; D012023:Reflex, Monosynaptic