Hand use for grasping in a bimanual task: evidence for different roles?

Abstract

It has been proposed that the two hands play different roles during bimanual object interaction. The right hand takes on an explorative, highly precise, manipulative role while the left hand supports and stabilizes the object. Does this division of labour influence hand use during visually guided grasping? Three experiments were designed to address this question: right-handed individuals put together 3D models using big or small building blocks scattered across a tabletop. Participants were free to build the models; however, it felt comfortable (Experiment 1) or they were required to build on a large (Experiment 2) or small (Experiment 3) base plate. In Experiment 1, the right hand was preferred for grasping while the left hand stabilized the building model. When participants used the large base plate (Experiment 2), right hand use for grasping decreased and left hand use increased. The plate provided freedom to the left hand from having to stabilize the building model, but it also interfered with right/left hand movements directed towards the opposite side of the grasping hand (contralateral movements). To investigate which of these two factors would explain the change in hand use for grasping, a very small base plate was used in the last experiment. Results showed similar right hand use values to those seen in the first experiment (without the use of a plate), even though the left hand was 'released from its stabilizing duties.' The results predict a left-hemisphere right hand advantage in the control of grasping.

One hand or the other? Effector selection biases in right and left handers

“…Although our sample size is comparable to many of the other hand choice studies reviewed above, the recent extensions of the Gonzalez puzzle/model paradigm using a distinct sample of left handers (Gonzalez & Goodale, 2009;Stone et al, 2013) suggests that using their paradigm the effects are reliably obtained.…”

Manual preferences for visually- and haptically-guided grasping

“…Tests of normality (Kolmogorov-Smirnov & ShapiroWilk) revealed that the data was normally distributed. An analysis of variance (ANOVA) was performed on the values of right-hand use, as in previous reports using similar tasks and measures (Bryden & Huszczynski, 2011;Bryden, Pryde & Roy, 2000;Cavill & Bryden, 2003;de Bruin, Bryant & Gonzalez, 2014;Sacrey, Arnold, Whishaw & Gonzalez, 2013;Stone & Gonzalez, 2014a,b;Stone et al, 2013).…”

“…Not surprisingly, vision also plays a critical role in hand preference for grasping. During visually-guided grasping tasks, individuals (even some left-handed) exhibit a clear preference to grasp objects with the right-hand (Bishop, Ross, Daniels & Bright, 1996;Calvert & Bishop, 1998;Gabbard & Rabb, 2000;Gonzalez & Goodale, 2009;Jacquet, Esseily, Rider & Fagard, 2012;Stone & Gonzalez, 2014a;Stone, Bryant & Gonzalez, 2013). The role of haptics in hand preference for grasping however, has been seldom investigated.…”

“…We recently investigated this question using the block building task (Gonzalez & Goodale, 2009;Stone & Gonzalez, 2014a,b;Stone et al, 2013) and found that when individuals are blindfolded and must use only their sense of touch to complete the task (rendering it a haptically-guided task), no hand preference is observed (Stone & Gonzalez, 2014a,b). As haptic discrimination of the building blocks plays a central role in the task, these results pose the question: is this decrease in right-hand use (or increase in left-hand use) due to a left-hand advantage for haptic discrimination?…”

“…Right-and left-handed individuals were tested on the block building task (see Gonzalez, Whitwell, Morrissey, Ganel & Goodale, 2007;Stone & Gonzalez, 2014a;Stone et al, 2013). Participants in four different groups (Vision/normal haptic feedback (V/H), No Vision/normal haptic feedback (NV/H), Vision/constrained haptic feedback (V/Constrained-H), No Vision/constrained haptic feedback (NV/Constrained-H)) were asked to replicate 3D models from a tabletop of evenly distributed building blocks.…”