Two forms of touch perception in the human brain.
We compared the judgment of distance between two simultaneous tactile stimuli applied to different body parts, with judgment of intensity of skin contact of the very same stimulation. Results on normal subjects showed that both tasks bilaterally activate parietal and frontal areas. However, the evaluation of distances on the body surface selectively activated the angular gyrus and the temporo-parieto-occipital junction in the right hemisphere. The different involvement of the brain areas in the two tactile tasks is interpreted as the need for using a Mental Body Representation (MBR) in the distance task, while the judgment of the intensity of skin deflection can be performed without the mediation of the MBR. The present study suggests that the cognitive processes underlying the two tasks are supported by partially different brain networks. In particular, our results show that metric spatial evaluation is lateralized to the right hemisphere.
Department of Psychology, Sapienza University of Rome, Rome, Italy. grazia.spitoni@uniroma1.it
Grazia Fernanda
GF
Spitoni
Gaspare
G
Galati
Gabriella
G
Antonucci
Patrick
P
Haggard
Luigi
L
Pizzamiglio
D000328:Adult; D000344:Afferent Pathways / Q000033:anatomy & histology / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D005260:Female; D006801:Humans; D007600:Judgment / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000592:standards; D010812:Physical Stimulation / Q000379:methods; D014110:Touch / Q000502:physiology*; D055698:Touch Perception / Q000502:physiology*; D055815:Young Adult