Visual peripersonal space centred on the face in humans

Abstract

A convergent series of studies in monkeys and man suggests that the computation of visual space is performed in several brain regions for different behavioural purposes. Among these multiple spatial areas, the ventral intraparietal cortex, the putamen and the ventral aspect of the premotor cortex (area 6) contain a system for representing visual space near the face (peripersonal space). In these cerebral areas some neurons are bimodal: they have tactile receptive fields on the face, and they can also be driven by visual stimuli located near the tactile field. The spatial correspondence between the visual and tactile receptive fields provides a map of near visual space coded in body-part-centred co-ordinates. In the present study we demonstrate for the first time the existence of a visual peripersonal space centred on the face in humans. In patients with right hemispheric lesions, visual stimuli delivered in the space near the ipsilesional side of the face extinguished tactile stimuli on the contralesional side (cross-modal visuotactile extinction) to the same extent as did an ipsilesional tactile stimulation (unimodal tactile extinction). Furthermore, a visual stimulus presented in the proximity of the contralesional side of the face improved the detection of a left tactile stimulus: i.e. under bilateral tactile presentation patients were more accurate to report the presence of a left tactile stimulus when a simultaneous visual stimulus was presented near the left side of the face. However, when visual stimuli were delivered far from the face, visuotactile extinction and visuotactile facilitation effects were dramatically reduced. These findings are consistent with the hypothesis of a representation of visual peripersonal space coded in bodypart-centred co-ordinates, and they provide a striking demonstration of the modularity of human visual space.

Is That within Reach? fMRI Reveals That the Human Superior Parieto-Occipital Cortex Encodes Objects Reachable by the Hand

“…This space in which the body's effectors can act is termed peripersonal space (Rizzolatti et al, 1985;Previc, 1998) and may be particularly relevant for the visuomotor areas of the brain. Indeed, studies with parietal patients exhibiting extinction (di Pellegrino et al, 1997;Làdavas et al, 1998aLàdavas et al, ,b, 2000 and neglect (Halligan and Marshall, 1991;Berti and Frassinetti, 2000), as well as studies with neurologically intact individuals (Weiss et al, 2000;Makin et al, 2007;Quinlan and Culham, 2007), suggest that parietal cortex may preferentially encode near space.…”

Detecting peripersonal space: The promising role of ultrasonics

“…In fact, PI increased more in the p1→p2 , that is, with the hand approaching the PPS face, and p2→p3 transition, that is, with the hand leaving the PPS face, than the other positions. The greater amount of PI changes in such hand positions may depend on the fact that the visual experience of the moving upper limb, as in the p1→p2 and p2→p3 transitions, potentiates the processing of feel‐touch experience (Làdavas, Zeloni, & Farnè, 1998). On the other hand, motor (intentional outflow) and sensory (inflow) information are sufficient to tune CBF when the visual experience is not available, as in the p0→p1 and p3→p4 transitions (Blakemore, Wolpert, & Frith, 2002; Haggard, 2005; Wolpert & Flanagan, 2001; Wolpert, Ghahramani, & Jordan, 1995).…”

Evaluation of headache intensity in migrainous patients with visual handicap through the tactile analogical scale (TAS)

“…The bimodal cells show visual and tactile receptive fields distributed predominantly on the face, arm and parts of the superior trunk. With the integration between tactile and visual perception the human brain structures visual-spatial maps for the hand, arm and face [9][10][11] . The visual spatial perceptive integration for the face involves the optic nerve and trigeminal nerve.…”