1. By Mayank Sharma

2. A cluster of symptoms characterised by involuntary movement of an upper limb in conjunction with the experience of estrangement from or personification of the movements of the limb itself.

3. Head trauma Cerebral hemispheric stroke Tumor CNS infection Corpus Callosal surgery for epilepsy Degenerative dementia (ex. Alzheimer’s)

4. Two frontal varieties: 1.Lesions of the language dominant medial frontal cortex and the anterior corpus callosum affecting the dominant hand 2.Lesion within the corpus callosum alone affecting the non-dominant hand.

5. 1.The Frontal variant: Disinhibited groping (unintentionally reaching out for objects with the affected arm’s reach) 2.The Callosal variant: The patient’s hand counteracts voluntary actions performed by the other hand. 3.Sensory alien hand variant: Ataxic limb movements associated with anaesthesia of the limb

6. A 71-year-old right-handed woman developed acute left hemiparesis and visual hallucinations. She also complained that her left hand uncontrollably scratched her and pulled at her hair. Past medical history was notable for chronic hypertension and triple coronary artery bypass graft 6 years earlier. Cranial CT scan indicated acute right parietal cortical infarct and extensive bilateral subcortical white matter ischemic changes.

7. Disinhibited groping that occurs consistently with tactile or visual stimulation is primarily related to medial frontal lobe injury Self-oppositional behaviour occurs more variably in the patient and is primarily associated with mid-callosal damage The feeling of alienation likely results from the combination of disinhibited, excessively reactive responses that appear to be purposeful

8. Potentially self-injurious behaviours by the hand have been reported, such as self-slapping and self-choking Unwanted violent actions directed toward the examiner were reported in one case of frontal alien hand The alien hand's grasping a hot utensil or a sharp or self- powered tool, particularly an automobile steering wheel – can be dangerous and must be prevented

9. When alien hand originates from focal injury of acute onset, recovery generally occurs within a year Alien hand associated with progressive degenerative cerebral disorder may persist until the patient dies No rehab for alien hand syndrome has been established To prevent compulsive grabbing, oven mitts have been used for some patients Some instances of frontal alien hand responded well to constant visual or tactile contact, including warm water application

10. Action tremor Chorea Hemiballismus Disinhibited grasp reflex (in focal cerebral injury) Psychogenic dystonia Unilateral spontaneous arm levitation Cortical-basal ganglionic degeneration Progressive supranuclear palsy

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