title: Anosognosia for hemianaesthesia: a voxel-based lesion-symptom mapping study.
abstract: Brain-damaged patients affected by hemianaesthesia (i.e., the loss of tactile sensibility on the contralesional side of the body) may deny their deficits (i.e., anosognosia for tactile deficits) even reporting tactile experience when stimuli are delivered on the impaired side. So far, descriptive analysis on small samples of patients reported that the insular cortex, the internal/external capsule, the basal ganglia and the periventricular white matter would subserve anosognosia for hemianaesthesia. Here, we aimed at examining in depth the anatomo-functional nature of anosognosia for hemianaesthesia by means of a voxelwise statistical analysis. We compared two groups of left hemiplegic patients due to right brain damages differing only for the presence/absence of anosognosia for left hemianaesthesia. Our findings showed a lesional cluster confined mainly to the anterior part of the putamen. According to the current anatomical evidence on the neural basis of sensory expectancies, we suggested that anosognosia for hemianaesthesia might be explained as a failure to detect the mismatch between expected and actual tactile stimulation.
authors.affiliation: SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy; Neuroscience Institute of Turin (NIT), University of Turin, Italy. Electronic address: lorenzo.pia@unito.it.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Pia
authors.affiliation: Department of Rehabilitation, Hospital Company 'S. Antonio Abate', Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Spinazzola
authors.affiliation: SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Garbarini
authors.affiliation: Department of Rehabilitation, Hospital Company 'S. Antonio Abate', Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Bellan
authors.affiliation: SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Piedimonte
authors.affiliation: SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy.
authors.forename: Carlotta
authors.initials: C
authors.lastname: Fossataro
authors.affiliation: SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Livelli
authors.affiliation: SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy.
authors.forename: Dalila
authors.initials: D
authors.lastname: Burin
authors.affiliation: SAMBA (SpAtial, Motor & Bodily Awareness) Research Group, Psychology Department, University of Turin, Italy; Neuroscience Institute of Turin (NIT), University of Turin, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Berti
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000377:Agnosia / Q000175:diagnosis / Q000503:physiopathology*; D000758:Anesthesia / Q000379:methods; D001364:Awareness / Q000502:physiology*; D001930:Brain Injuries / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests
keywords: Anosognosia for hemianaesthesia; Anterior putamen; Somatosensory awareness; Somatosensory expectancies