The Role of White Matter Disconnection in the Symptoms Relating to the Anarchic Hand Syndrome: A Single Case Study

Abstract

The anarchic hand syndrome refers to an inability to control the movements of one’s own hand, which acts as if it has a will of its own. The symptoms may differ depending on whether the brain lesion is anterior, posterior, callosal or subcortical, but the relative classifications are not conclusive. This study investigates the role of white matter disconnections in a patient whose symptoms are inconsistent with the mapping of the lesion site. A repeated neuropsychological investigation was associated with a review of the literature on the topic to identify the frequency of various different symptoms relating to this syndrome. Furthermore, an analysis of the neuroimaging regarding structural connectivity allowed us to investigate the grey matter lesions and white matter disconnections. The results indicated that some of the patient’s symptoms were associated with structures that, although not directly damaged, were dysfunctional due to a disconnection in their networks. This suggests that the anarchic hand may be considered as a disconnection syndrome involving the integration of multiple antero-posterior, insular and interhemispheric networks. In order to comprehend this rare syndrome better, the clinical and neuroimaging data need to be integrated with the clinical reports available in the literature on this topic.

Could Brain–Computer Interface Be a New Therapeutic Approach for Body Integrity Dysphoria?

“…Typical damaged brain areas include fronto-mesial and anterior cingulate areas as well as the anterior corpus callosum (Feinberg et al, 1992). Anarchic hand syndrome (AHS) is a related disorder, which ensues from a relatively circumscribed lesion of the anterior corpus callosum (Feinberg et al, 1992, but see Pacella et al, 2021 for a more recent account). In this syndrome, the individuals' hands move outside of the volitional control as well (Della Sala, 2009;Jenkinson et al, 2015); however, intermanual conflicts are more typical than utilization behavior.…”

“…hand syndrome Disembodiment of the limb Potential underlying mechanism relating to white matter disconnection and brain lesions (Pacella et al, 2021) Motor control of the affected limb is disinhibited and moves non-volitionally No disownership of the limb -Right inferior parietal lobe (Della Sala, 2009; Jenkinson et al, 2015)-White matter disconnection of antero-posterior, insular, and interhemispheric networks(Pacella et al, 2021) …”

The effect of damage to the white matter network and premorbid intellectual ability on postoperative verbal short-term memory and functional outcome in patients with brain lesions

“…They showed that spatial neglect is associated with disconnection of superior longitudinal fasciculus (SLF) II measured using this indirect approach, and that this result is supported by individual white matter tractography dissection [36]. Pacella et al, [38] also depicted a patient's lesion as a region of interest (ROI), which they overlaid an atlas of white matter tracts created from healthy DWI data to measure the disconnection of the white matter tract of the ROI using Tractotron in the BCB toolkit [35]. The disconnections of white matter tracts such as the SLF, arcuate fasciculus (AF), and inferior longitudinal fasciculus indicated by the indirect approach were also confirmed in subsequent direct analysis using DTI [38].…”

“…Pacella et al, [38] also depicted a patient's lesion as a region of interest (ROI), which they overlaid an atlas of white matter tracts created from healthy DWI data to measure the disconnection of the white matter tract of the ROI using Tractotron in the BCB toolkit [35]. The disconnections of white matter tracts such as the SLF, arcuate fasciculus (AF), and inferior longitudinal fasciculus indicated by the indirect approach were also confirmed in subsequent direct analysis using DTI [38]. Furthermore, Wawrzyniak et al, [39] successfully confirmed the wellknown relationship between damage to white matter tracts and symptoms caused by disconnection of specific white matter tracts using voxel-wise disconnection mapping as an indirect approach.…”