Mori and Yamadori (1982) first described a phenomenon of a compulsive manipulation of tools following an occulusion of the left anterior cerebral artery. We have also experienced a similar case and studied especially the clinical state of the compulsive manipulation of objects, a difference between this behavior and other similar phenomena, and the underlying neuropsychological mechanisms.
The patient was a 58-year-old man who had suffered from an occulusion of the left anterior cerebral artery. The site of lesion cofirmed by CT scan was the left medial frontal lobe and the anterior corpus callosum. In this case we observed the following characteristics in addition to the instinctive grasp reaction ; (1) He compulsively manipulated objects with his right hand. (2) He also compulsively took foods with the same hand. (3) His left hand inhibited this behavior of the right hand. (4) He used the object with faster rhythm than normal. (5) He could use the object with both hands together. (6) This manipulation of the right hand was repeated unless it was stopped.
We considered that this phenomenon was an extension of the grasping reflex, and the release of inhibitory mechanism occurred at the level of the learned movement. Thus the level of disturbance is lower than in the utilization behavior proposed by Lhermitte, but higher than in the instinctive grasp reaction.
