Hypermetamorphosis (psychology)

Utilization behavior (UB) is a type of neurobehavioral disorder that involves patients grabbing objects in view and starting the 'appropriate' behavior associated with it at an 'inappropriate' time. Utilization behavior patients have difficulty resisting the impulse to operate or manipulate objects which are in their visual field and within reach. Characteristics of UB include unintentional, unconscious actions triggered by the immediate environment. The unpreventable excessive behavior has been linked to lesions in the frontal lobe. UB has also been referred to as "bilateral magnetic apraxia" and "hypermetamorphosis".

The patients who display utilization behavior tend to reach out and begin to automatically use objects in the visual field of their environment. This may not seem incorrect but the difference in action to a person without UB is that the "object-appropriate" action taken is performed at the inappropriate time. For example, a patient in a doctor's office sees a toothbrush and will involuntarily start brushing his teeth. This demonstrates the appropriate action (brushing) at the inappropriate time (office). This dysfunction of the frontal area causes the inappropriate motor responses to specific objects in the environment.

Patients with utilization behavior feel they are functioning normally and do not believe that their actions are anything out of the ordinary. Sufferers are unable to resist grasping or using an object placed in front of them, regardless of the context or environment. It is not known what triggers them to exhibit UB with certain external stimuli and not others.

A disorder related to UB consists of the feeling that a body part is separate from the rest of the body and has a mind of its own. The patient does not recognize the limb as one that he/she owns and believes it to be a foreign object which he cannot control. This set of symptoms is related to Alien Hand Syndrome (AHS), a neurological disorder in which the subject does not acknowledge ownership of a limb when visual cues are lacking. AHS can involve damage to the anterior cingulate gyrus, the medial prefrontal cortex and the anterior corpus callosum when a patient has frontal AHS. The other type of AHS, callosal AHS, is due to an anterior callosal lesion and affects dominant hemisphere control.

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