Medial frontal cortex infarction and the alien hand sign

Journal of Neurology, Neurosurgery & Psychiatry, 1988

Three patients with dominant anterior cerebral artery territory infarction demonstrated a severe disturbance of upper limb motor control with impaired bimanual coordination, the "alien hand" sign, and intermanual conflict, in addition to signs of callosal interruption and a transcortical motor aphasia. Recordings of movement-related potentials in one patient showed an attenuated Bereitschaftspotential and a greater asymmetry of the NS' component of the premotor negativity with left finger than with right finger movement. The impairment of bimanual motor control and associated abnormal motor behaviour of the right hand in these cases are postulated to be due to involvement of the supplementary motor area and related areas of the medial frontal cortex.

Neuropsychology, 2013

Objective: Motor intentional disorders (MIDs) are characterized by dysfunction in the preparation, initiation, maintenance, and termination of goal-oriented actions. In this study, we investigated (1) whether patients with right hemisphere strokes (RHS) and left hemisphere strokes (LHS) differ in the frequency of delayed action initiation (hypokinesia) and motor impersistence; (2) whether there is a directional or hemispatial component of hypokinesia or motor impersistence; (3) whether there is an association between the presence of hemispatial neglect and tests for MID; and (4) the location of injury associated with MID. Method: Thirty-two patients with acute unilateral stroke (21 with RHS and 11 with LHS) and 12 age-matched healthy controls participated in the study. To determine the presence and severity of directional and spatial hypokinesia and impersistence we used a new apparatus, the Directional Movement Tester (DMT). While being tested with the DMT, the participants held a static bar located either in the right or left hemispace using either their right or left hand and upon stimulus onset pushed the bar either leftward or rightward and maintained a given force for 10 sec. The frequency of hypokinesia and impersistence was higher in the RHS group than in the LHS group, but there were no hypokinetic directional or spatial asymmetries. The RHS group did demonstrate left contralesional directional impersistence, but there were no spatial asymmetries of impersistence. Signs of hemispatial neglect were not associated with these measures of MID. Participants with frontal or subcortical lesions were significantly more likely to demonstrate hypokinesia and impersistence than those with posterior lesions.

Annals of rehabilitation medicine, 2015

We report a patient with a severe limitation of function in the right hand resulting from grasp reflex following a stroke affecting the left anterior cerebral artery region. We describe, using diffusion tensor tractography (DTT), a disconnection between the bilateral frontal lobes via the corpus callosum. The patient could not control his right hand at all, even though his bilateral corticospinal tracts were intact. We noted that over the infarcted lesion on DTT, the white matter was invisible from the corpus callosum to the prefrontal cortex. These findings reflected a unique pattern of white-matter disconnection between the ipsilateral medial frontal lobe and ipsilateral and contralateral frontal cortex causing hand function deterioration in the form of severe grasp reflex.

Neuropsychologia, 1995

Neurobehavioral studies of gesturing have been largely limited to left hemisphere damaged (LHD) patients. We compared spontaneous gesturing in seven right hemisphere damaged (RHD) patients, seven LHD patients, and seven normal controls (NHD) during videotaped interviews. Two judges coded symbolic, expressive, grooming, and fidgeting gestures in 120 10-sec intervals of videotape per patient. We found that RHD patients made significantly more total gestures and grooming gestures with the hand ipsilateral to their lesion than did LHD patients. Furthermore, RHD patients made more total and grooming gestures with their right hand than NHD subjects did with either hand. There were no differences in gesture production between the right and left hands of NHD patients. These results suggest that RHD produces enhanced gesturing, particularly involving grooming behavior. 203 204 L.X. BLONDER et al. fewer novel finger positions and that both left and right frontal-lesioned patients produced fewer meaningful gestures (e.g. the hitch-hiking sign) in comparison to normal controls. Several studies have examined gestural communication in LHD patients, but the results are conflicting (see LeMay et al. 1-38] for a brief review). Herrmann et al. 1, conducted interviews with seven global aphasics and their partners and compared the use of arm, head, and body movements by both members of the dyad. They found that aphasics used significantly more bodily gestures than their partners. The authors note that the majority of codified gestures produced by the aphasic patients were head nods and shakes, and shoulder shrugs. Since the neural mechanisms controlling such movements may be bilateral, this result is not surprising . LeMay et al. showed that Broca's aphasics produced more hand gestures during speech than Wernicke's aphasics and non-aphasic controls. Borod et al. found that limb apraxia was positively correlated with gestural communication in LHD patients such that the greater their apraxia scores the poorer their gestural communication skills. This study was based on retrospective ratings by nurses rather than direct coding of spontaneous gestures. Macauley et al. found that LHD ideomotor apraxics with aphasia produced fewer emphatic gestures (expressive gestures that accompany speech) and more fillers (gestures produced during pauses) than non-apraxic, non-aphasic controls during structured dyadic interviews conducted in the hospital. Nonapraxic aphasics were not assessed. None of the above studies examined gesturing by RHD patients.

Cognitive and Behavioral Neurology, 2009

Objective: Damage to premotor and prefrontal regions results in motor intentional disorders (MIDs) that disrupt initiation, maintenance, and termination of volitional movements. MIDs occur more frequently after right than left hemisphere injury. The aim of this study was to evaluate the prevalence of MIDs in patients with right hemisphere stroke and the factors that have influence on MIDs.

NeuroReport, 1996

Neuropsychologia, 1997

We report evidence of isolated conceptual knowledge in the right hemisphere of a woman with chronic anarchic hand sign after ischemic infarction of the central four-fifths of the corpus callosum. Limited visual information was available to the right hemisphere, access to medial temporal structures subserving memory was disrupted and disconnection from left hemisphere language structures was complete. Still, the right hemisphere could build mental representations of objects via tactile input and use them in cross-modal matching. These representations were not accessed consistently in auditory comprehension or naming tasks. This functional specificity and its pathoanatomical correlates demonstrate that the study of anarchic hand sign can illuminate not just motor control issues but may inform our understanding of the representation and lateralization of conceptual knowledge as well.

Neurocase, 2014

Anarchic hand syndrome (AHS) is characterized by goal-directed movements performed without volitional control (agency). Different AHS subtypes have been identified; however, few studies have examined the posterior subtype. We report a case of AHS following right-hemisphere parietal damage, with left-sided somatosensory and proprioceptive impairment. Agency was examined for nonanarchic (volitional) movements performed using the anarchic hand. The patient experienced abnormal agency for movements whether motor intention and visual feedback were congruent or incongruent, but not when intention was absent (passive movement). Findings suggest a general disturbance of veridical motor awareness and agency in this case of parietal AHS.

Archives of Physical Medicine and Rehabilitation, 1999

Neuropsychologia, 2001

Signs of unilateral neglect for events occurring in one hemispace most often result from right hemisphere lesions. Right unilateral neglect after left hemisphere damage is much rarer, and has received less attention. The present study explores the relationships between right unilateral neglect and asymmetries in producing laterally directed arm movements in the horizontal plane in left brain-damaged (LBD) patients. Participants produced right-or left-directed arm movements with their left arm in response to centrally located visual stimuli. Results showed that LBD patients with signs of right unilateral neglect were consistently slowed when producing arm movements toward the right (neglected) side, as compared to left-directed movements. Taking into account patients with and without signs of neglect, this directional asymmetry positively correlated with a reaction-time measure of perceptual spatial bias. These findings stand in contrast with previous results obtained with the same experimental paradigm in right brain-damaged patients, in whom a consistent slowing of leftward-directed movements was rare and apparently unrelated to the presence and severity of left neglect. These conflicting results are discussed with respect to the hypothesis that different mechanisms may underlie left and right unilateral neglect.