Effect of visual and haptic feedback on grasping movements

Abstract

Bozzacchi C, Volcic R, Domini F. Effect of visual and haptic feedback on grasping movements.

Lack of depth constancy for grasping movements in both virtual and real environments

“…Based on the empirical evidence that binocular cues do not yield an accurate metric space representation (Bingham et al 2001;Volcic et al 2013;Johnston et al 1991;Brenner et al 1997;Brenner and van Damme 1999;Hibbard and Bradshaw 2003), we expect to find a modulation of the MGA as function of distance in the virtual condition, where only binocular cues are available, resembling the effects previously described for perceptual and grasping tasks (Volcic et al 2013;Bozzacchi et al 2014). Specifically, we predict a reduction of the MGA of ϳ3 mm per 100 mm separating the closest from the furthest object distance (slope: ϳ0.03).…”

“…Furthermore, errors similar to those in perceptual estimates were also found for grasping movements towards target objects only defined by binocular information (Bingham et al 2007;Hibbard and Bradshaw 2003;Bozzacchi et al 2014). In particular, by using virtual reality setups, we observed that even at the presence of both visual and haptic feedback, the grip aperture (GA) decreases with the increase of object egocentric distance, a clear index of depth constancy failure (Bozzacchi et al 2014). Remarkably, the effects reported in our previous study are strongly consistent with findings from perceptual paradigms.…”

“…Undoubtedly, the availability of different sources of feedback at the end of an action, like the vision of the hand and the physical presence of a target, plays a crucial role in guiding the limb to the appropriate contact position on the object (Jakobson and Goodale 1991;Gentilucci et al 1994;Connolly and Goodale 1999;Churchill et al 2000). As largely demonstrated, the absence of such feedback can induce atypical patterns of movements (Wing et al 1986;Gentilucci et al 1994;Churchill et al 2000;Bingham et al 2007;Hibbard and Bradshaw 2003;Bozzacchi et al 2014). These findings are in agreement with a theoretical framework postulating a nonmetric (i.e., non-Euclidean) representation of 3D properties.…”

“…In reaching tasks without haptic feedback spatial distortions were found in both egocentric distance and object size estimation (Bingham et al 2000(Bingham et al , 2001. Furthermore, errors similar to those in perceptual estimates were also found for grasping movements towards target objects only defined by binocular information (Bingham et al 2007;Hibbard and Bradshaw 2003;Bozzacchi et al 2014). In particular, by using virtual reality setups, we observed that even at the presence of both visual and haptic feedback, the grip aperture (GA) decreases with the increase of object egocentric distance, a clear index of depth constancy failure (Bozzacchi et al 2014).…”

“…al. 2013) and grasping (Bozzacchi et al 2014) paradigms. The comparison between the three slopes showed no significant effect of condition [F(2,28) ϭ 0.36; P ϭ 0.69].…”