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Alien Hand Syndrome

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Han Young Jung – 1st expert on this subject based on the ideXlab platform

  • Alien Hand Syndrome in Stroke – Case Report & Neurophysiologic Study –
    Annals of Rehabilitation Medicine, 2012
    Co-Authors: Yong Won Park, Hyung Joon Jeong, Han Young Jung

    Abstract:

    Alien Hand Syndrome is defined as unwilled, uncontrollable, but seemingly purposeful movements of an upper limb. Two major criteria for the diagnosis are complaint of a foreign limb and complex, autonomous, involuntary motor activity that is not part of an identifiable movement disorder. After a cerebrovascular accident in the corpus callosum, the parietal, or frontal regions, various abnormal involuntary motor behaviors may follow. Although different subtypes of Alien Hand Syndrome have been distinguished, this classification clearly does not cover the wide clinical variety of abnormal motor behaviors of the upper extremity. And there are few known studies about the neurophysiology of this Syndrome using transcranial magnetic stimulation (TMS). We recently experienced 2 rare cases of Alien Hand Syndrome which occurred after anterior cerebral artery (ACA) infarction. A 72 year-old male with right hemiplegia following a left ACA infarct had difficulty with voluntarily releasing an object from his grasp. A 47 year-old female with left hemiplegia following a right ACA infarct had a problem termed ‘intermanual conflict’ in which the two Hands appear to be directed at opposing purposes. Both of them had neurophysiologic studies done, and showed reduced amplitude by single pulse MEP and a lack of intracortical inhibition (ICI) by paired pulse TMS. No abnormalities were found in SSEP.

  • Alien Hand Syndrome in stroke case report neurophysiologic study
    Annals of Rehabilitation Medicine, 2012
    Co-Authors: Yong Won Park, Hyung Joon Jeong, Han Young Jung

    Abstract:

    Alien Hand Syndrome is defined as unwilled, uncontrollable, but seemingly purposeful movements of an upper limb. Two major criteria for the diagnosis are complaint of a foreign limb and complex, autonomous, involuntary motor activity that is not part of an identifiable movement disorder. After a cerebrovascular accident in the corpus callosum, the parietal, or frontal regions, various abnormal involuntary motor behaviors may follow. Although different subtypes of Alien Hand Syndrome have been distinguished, this classification clearly does not cover the wide clinical variety of abnormal motor behaviors of the upper extremity. And there are few known studies about the neurophysiology of this Syndrome using transcranial magnetic stimulation (TMS). We recently experienced 2 rare cases of Alien Hand Syndrome which occurred after anterior cerebral artery (ACA) infarction. A 72 year-old male with right hemiplegia following a left ACA infarct had difficulty with voluntarily releasing an object from his grasp. A 47 year-old female with left hemiplegia following a right ACA infarct had a problem termed ‘intermanual conflict’ in which the two Hands appear to be directed at opposing purposes. Both of them had neurophysiologic studies done, and showed reduced amplitude by single pulse MEP and a lack of intracortical inhibition (ICI) by paired pulse TMS. No abnormalities were found in SSEP.

Shawn D Gale – 2nd expert on this subject based on the ideXlab platform

  • posterior variant Alien Hand Syndrome clinical features and response to rehabilitation
    Disability and Rehabilitation, 2002
    Co-Authors: B C Pack, K J Stewart, Paul T Diamond, Shawn D Gale

    Abstract:

    Purpose : This case highlights the clinical features and course of recovery of a patient presenting to the rehabilitation service with posterior-variant Alien Hand Syndrome (AHS) following thalamic stroke. Methods : Single case report. Results : Clinical signs and symptoms included mild hemiparesis, dyspraxia, dysmetria, primary sensory loss and hemispatial neglect. Autonomous movements and personification of the affected extremity which were ego-syntonic in nature were characteristic of posterior-variant AHS. The associated neurological impairments resolved early during the course of rehabilitation and the patient made excellent functional gains. Conclusion : This case highlights the distinguishing features differentiating posterior-variant AHS from more classical AHS and underscores the excellent prognosis of this variant.

Anjan Chatterjee – 3rd expert on this subject based on the ideXlab platform

  • the Alien Hand Syndrome what makes the Alien Hand Alien
    Cognitive Neuropsychology, 2006
    Co-Authors: Iftah Biran, Tania Giovannetti, Laurel J Buxbaum, Anjan Chatterjee

    Abstract:

    The Alien Hand Syndrome is a deeply puzzling phenomenon in which brain-damaged patients experience their limb performing seemingly purposeful acts without their intention. Furthermore, the limb may interfere with the actions of their normal limb. We report a case of Alien Hand Syndrome following a left medial frontal and corpus callosum ischemic lesion. From our clinical observations and the patient’s performances on experimental tasks, we postulate that three factors contribute to the sense of Alienness: First, the errant limb must be disinhibited and disproportionately reactive to external environmental stimuli. Second, the limb is under less volitional control and produces perseverative movements in which motor stereotypies are concatenated. Consequently, the disinhibited limb perseverates on external stimuli and appears purposeful, despite not being engaged in true goal-directed intentions. Finally, the patient needs to have a relatively intact action-monitoring system to be aware of the abnormal movements as they are occurring.

  • reduced endogenous control in Alien Hand Syndrome evidence from naturalistic action
    Neuropsychologia, 2005
    Co-Authors: Tania Giovannetti, Iftah Biran, Laurel J Buxbaum, Anjan Chatterjee

    Abstract:

    Patients with Alien Hand (AH) Syndrome from medial frontal lesions exhibit involuntary but seemingly purposeful contralesional upper limb movements. Two observations about AH patients have received little, if any, experimental confirmation. The first is that AH is triggered opportunistically by nearby objects. The second is that AH behaviors are increased in conditions of fatigue or anxiety, i.e. under reduced attentional control. A prominent account explains AH as reduced intention-driven (endogenous) executive control. This account predicts that erroneous AH behaviors should be driven by environmental (i.e. exogenous) factors, such as distractor proximity to the Hand. AH errors should be less influenced by the intention or action plan (i.e. endogenous factors), such as the semantic relatedness of distractors to targets. Moreover, due to capacity limitations of the endogenous controller, AH behaviors should increase under conditions of secondary task load. We tested these predictions with an AH patient in two experiments using a naturalistic coffee-making task. Experiment 1 demonstrated that the affected Hand was highly perseverative and strongly influenced by exogenous but not endogenous factors. The non-Alien Hand made fewer errors. Experiment 2 showed that there was a disproportionate increase in perseverations and exogenous errors of the affected Hand under secondary task load. The non-Alien Hand was significantly less disrupted by dual task conditions. These data provide experimental support for previous anecdotal observations about AH behavior in naturalistic settings, and are consistent with a unilateral defect in endogenous control.

  • Alien Hand Syndrome
    JAMA Neurology, 2004
    Co-Authors: Iftah Biran, Anjan Chatterjee

    Abstract:

    In Stanley Kubrick’s movie Dr Strangelove ,the main character is described as “erratic” and displays a bizarre movement disorder. His right Hand seems to be driven by a will of its own, at times clutching his own throat and at other times raising into a Nazi salute. Dr Strangelove must try to restrain this wayward limb with his left Hand. Bizarre as this fictional character is, a similar movement disorder can occur in neurologic disease. The complex phenomenon associated with this disorder falls under the rubric of Alien Hand Syndrome. This Syndrome is characterized by a limb that seems to perform meaningful acts without being guided by the intention of the patient. Patients find themselves unable to stop the Alien limb from reaching and grabbing objects, and they may be unable to release these grasped objects without using their other Hand to pry open their fingers. These patients frequently express astonishment and frustration at the errant limb. They experience it as being controlled by an external agent and often refer to it in the third person. This article outlines the origins of the terminology used in describing this Syndrome, early observations, and studies regarding its functional neuroanatomy.