Alien Hand Syndrome (AHS)
Overview
Alien hand syndrome (AHS), also called (Dr. Strangelove syndrome)[1]:is a brain damaging disorders which the patient performs actions that appear intentional without his intention[2]. The afflicted individual may occasionally reach for and manipulate objects against their will, even to the extent of needing to restrain the alien hand with the controllable hand[3].
The non-dominant (left) hand in right handed people is most frequently affected by AHS. Findings are not necessarily limited to the upper limb because it can also affect the leg [4].
Signs and Symptoms
Alien hand syndrome can affect three regions of the brain: the frontal, callosal, and posterior regions. Depending on the area of injury the symptom will appears:
Frontal region (most commonly affects the dominant hand): People with the frontal variant of AHS have trouble controlling their hand groping or grabbing. They struggle to control the motions, which appear to occur on their own, even though they are frequently aware that the limb is theirs.
Callosal region (most commonly affects non-dominant hand): When AHS affects the corpus callosum, which joins the right and left sides of the brain, it can cause agnostic dyspraxia, apraxia, tactile anomia, visual anomia, agraphia, neglect, alexia.[4]
Posterior region (more commonly affects the non-dominant hand): Individuals with posterior-region AHS may have decreased motor control (e.g., limb levitation, ataxia, non-purposeful or non-conflicting movements) and the brain may not identify the limb as their own.
Mixed alien hand syndrome[5]: In mixed AHS, the frontal and callosal variants combine and can cause involuntary grasping, uncoordinated hand movements, and difficulty performing tasks with one hand, causing the other to move instead.
Differential Diagnosis
While complicated involuntary limb motions or a sense of losing control over limbs can be present in a number of illnesses, these traits differ from those of the alien limb varieties. When diagnosing AHS, it is important to consider the clinical characteristics of alien hands and the company they maintain.[4]
- Pseudoathetosis Disorder
- Task-specific Limb Dystonia Disorder
- Grasp reflex Disorder
- Utilisation Behaviour Disorder
- Hemineglect Disorder
- Mirror Movements Disorder
- Focal Dystonia Disorder
- Hemiataxia Disorder
- Hemiballismus Disorder
Treatment
Unfortunately, there are no approved or suggested treatments for AHS; instead, anecdotal accounts of behavioural and pharmaceutical approaches are used to manage the condition Depending to the Injured Variant. [6]
Frontal region:
- Sensory tricks.
- Distracting tasks.
- Cognitive Behavioural Therapy for anxiety control.
- Verbal cues.
Posterior region:
- Botulinum toxin A.
- Clonazepam.
- Visualisation strategies.
- Spatial recognition tasks.
Physical Therapy
The following physical therapy methods have been suggested as potential treatments for AHS[7]:
- Visual feedback.
- Bimanual command activities.
References
- ↑ Panikkath R, Panikkath D, Mojumder D, Nugent K. The alien hand syndrome. InBaylor University Medical Center Proceedings 2014 Jul 1 (Vol. 27, No. 3, pp. 219-220). Taylor & Francis.
- ↑ Biran I, Giovannetti T, Buxbaum L, Chatterjee A. The alien hand syndrome: What makes the alien hand alien?. Cognitive Neuropsychology. 2006 Jun 1;23(4):563-82.
- ↑ Assal F, Schwartz S, Vuilleumier P. Moving with or without will: functional neural correlates of alien hand syndrome. Annals of Neurology: Official Journal of the American Neurological Association and the Child Neurology Society. 2007 Sep;62(3):301-6.
- ↑ 4.0 4.1 4.2 Hassan A, Josephs KA. Alien hand syndrome. Current neurology and neuroscience reports. 2016 Aug;16:1-0.
- ↑ Qu K, Gan L, Jiang W, Yu P, Dong M. Case report: good prognosis of mixed alien hand syndrome by verbal-Cue rehabilitation exercise. Frontiers in Neurology. 2021 Sep 8;12:718706.
- ↑ Sarva H, Deik A, Severt WL. Pathophysiology and treatment of alien hand syndrome. Tremor and Other Hyperkinetic Movements. 2014;4.
- ↑ Alvarez A, Weaver M, Alvarez G. Rehabilitation of alien hand syndrome complicated by contralateral limb apraxia. American journal of physical medicine & rehabilitation. 2020 Oct 1;99(10):e122-4.