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Fenomen anarchicznej r ki – zaburzenia intencjonalno ci ruchu dowolnegoKeywords: alien hand , anarchic hand , intentionality , movement , supplementary motor area Abstract: Feeling of strangeness of one’s own limb and/or itsunwanted spontaneous actions are phenomena observedin clinical practice for a long time, and often describedby a general term alien hand. In fact, a large heterogenicgroup of disorders with different characteristics(in terms of symptomatology and etiology) should beconsidered. There are many attempts to classify a rangeof such disorders; in this paper the authors furtherdiscuss a concept of anarchic hand (AH) to denote thecomplex actions of the limb, taking place beyond intentionof the patient. Such movements are not accompaniedby a specific feeling of non-belonging of own hand,which is the most important feature of the alien handsyndrome. The key issue of anarchic hand is a dissociationof correct movements (in terms of praxis) and theability to control them (i.e. the intentionality of action).In search of the pathomechanism of the phenomenona hypothesis assuming the functional differentiation ofpremotor cortex is considered (dual premotor systemshypothesis – DPMS). The lateral premotor system isinvolved in movements which constitute a direct responseto stimuli from the environment, while the medialpremotor system – structurally located within the supplementarymotor area (SMA) – can play a key role inthe regulation of conscious, intentional motor activity.Experimental studies support the hypothesis of the dissociationbetween the intended reaction and the automaticresponse as a primary mechanism of AH; they alsohighlight the relationship of anarchic hand syndromewith attentional processes. A hypothesis alternative toDPMS claims that the control of intentional human activity(including control of unwanted limb movement,which is the case in AH) is carried out by a parent, nonspecificsupervisory system. Currently no establishedstandards exist in the treatment of AH. However, todate a few reports on rehabilitation of AH patients havebeen published.
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