Computational protocol: Bodily ownership modulation in defensive responses: physiological evidence in brain-damaged patients with pathological embodiment of other’s body parts

Similar protocols

Protocol publication

[…] During the period between October 2013 and June 2015 eighteen brain-damaged patients of cerebrovascular origin, with contra-lesional upper limb sensory-motor deficits, were recruited at the “San Camillo” Hospital (Turin, Italy) and at the “Maria Ausiliatrice” Hospital (Turin, Italy). All patients were assessed using common neuropsychological tests: general cognitive tests (Montreal Cognitive Assessment – MOCA or Mini Mental State Evaluation - MMSE); visual field exam, with the score ranking from 0 to 3; assessment of the contralesional upper limb hemiplegia, as reported by the responsible neurologist and confirmed by a motor impairment examination carried out according to a clinical protocol, with the score ranking from 0 to 3 ; assessment of anosognosia for hemiplegia with the score ranking from 0 to 3, assessment of hemianesthesia, with the score ranking from 0 to 3; assessment of anosognosia hemianesthesia, with the score ranking from 0 to 3; tests for neglect (Behavioral Inattention Test - BIT – conventional and behavioral subtests; DILLER) and for personal neglect (FLUFF). Patients were also evaluated for somatoparaphrenia. See for details. Exclusion criteria were: 1) previous neurological or psychiatric history; 2) severe general cognitive impairment; 3) visual field deficits. In order to include patients in the experimental group, we tested them with an ad hoc protocol devised to assess the presence/absence of pathological embodiment, proposed in previous studies. According to this evaluation, nine out of eighteen patients were selected for the study. Patients’ brain lesions, as documented by clinical CT or MRI scans, are consistent with those described in previous studies. Lesions were mapped onto the MNI stereotactic space with standard MRI volume (voxels of 1 mm3) through a computerized technique. Image manipulations were obtained with the software MRIcron. Firstly, the MNI template was rotated on coronal, sagittal and horizontal planes according to the patient’s scan angle. Secondly, a skilled rater (LP) manually mapped the lesion onto each correspondent template slice, whereas a second skilled rater (CF) double-checked for the accuracy of the tracings for each patient. Thirdly, the maps were back rotated into the standard space. Grey matter involvement was obtained by superimposing the Anatomical Labelling map template AAL and the JHU-white matter template which categorize the distributions of digital images onto stereotactic space. The involved brain structures are summarized as following: E+1. Left-hemisphere lesions, involving: hippocampus, amygdala, middle temporal pole, parahippocampal gyrus, fusiform gyrus, heschl gyrus, temporo-parietal periventricular white matter, including superior longitudinal fasciculus (SLF). E+2. Right-hemisphere lesions, involving: Thalamus and sub-cortical white matter including posterior limb of internal capsule, retrolenticular part of internal capsule, superior corona radiata E+3 = Right-hemisphere lesions, involving: supramarginal gyrus, middle temporal pole, heschl gyrus, uncinate fasciculus, cingulum (hippocampus), posterior thalamus, retrolenticular part of internal capsule, putamen, sagittal stratum and temporo-parietal periventricular white matter, including SLF. E+4 = Right-hemisphere lesions, involving: precentral gyrus, inferior frontal operculum, inferior frontal gyrus (triangular part), inferior frontal gyrus (orbital part), rolandic operculum, insula, postcentral gyrus, supramarginal gyrus, angular gyrus, heschl gyrus, suoperioir temporal gyrus, temporal pole (superior part), middle temporal gyrus. fronto-temporo-parietal periventricular white matter, including SLF. E+5 = Right-hemisphere lesions, involving: middle frontal gyrus and fronto-parietal periventricular white matter, including SLF and superior corona radiate. Finally, we created a lesions overlap. Grey and white matter regions involvement were obtained by superimposing the Anatomical Labeling map template AAL and the JHU-white matter template. The overlay plot, showing an involvement of the SLF, is represented in .Five out of nine E+ patients (3 females, mean age ± standard deviation: 63.4 ± 9.68) showing a reproducible HBR (i.e., observed in five consecutive trials) were involved in the experiment, four right brain-damaged patients showing left-limb embodiment and one left brain-damaged patient showing right-limb embodiment. Additionally, one E− patient, with sensory-motor deficits similar to those shown by E+ patients (See ), was involved as control patient. Note that, during the task, the presence/absence of the pathological embodiment was also tested with an on-line embodiment evaluation (see Embodiment evaluation during the task). Finally, ten aged-matched healthy subjects (7 females, mean age ± standard deviation: 54.9 ± 8.06) were engaged in the experiment as control group. All participants were naive to the experimental procedure and to the purpose of the study and provide written informed consent to participate in the study. In accordance with the Declaration of Helsinki (BMJ 1991; 302: 1194) all the experimental procedures were approved by the Ethical Committee of the ASL TO 1 of Turin. […]

Pipeline specifications

Software tools MRIcron, AAL
Application Magnetic resonance imaging
Organisms Homo sapiens