Haptic orientation perception benefits from visual experience: Evidence from early-blind, late-blind, and sighted people

Abstract

Our haptic sense provides us with essential information about the spatial layout of peripersonal space-that is, the size, shape, position, and orientation of things within reach. Remarkably, haptic perception of basic spatial properties such as line length (Lanca & Bryant, 1995;Marks & Armstrong, 1996), path length (Lederman, Klatzky, & Barber, 1985), and orientation (see, e.g., Appelle & Countryman, 1986;Gentaz & Hatwell, 1998, 1999Kappers, 1999;Zuidhoek, Visser, Bredero, & Postma, 2004) is susceptible to marked distortions, at least in blindfolded sighted individuals. Interestingly, the distortions in haptic perception of orientation appear to be both systematic over multiple locations and consistent over different tasks-for example, the setting of a test bar either parallel or collinear with a reference bar, or the pointing of a bar toward a marker (Kappers, 1999(Kappers, , 2002Kappers & Koenderink, 1999). In the present study, we set out to investigate the nature of these systematic errors further by comparing blind participants to sighted controls.Kappers (2003) argued that setting two bars parallel to each other in a plane on the basis of touch alone typically recruits a mixture of egocentric (viz., hand-centered) and allocentric reference frames. The effect of the former is indicated by large, systematic errors-that is, clockwise with test bars to the right and counterclockwise with test bars to the left of the reference bar (see, e.g., Kappers, 1999Kappers, , 2003Kappers & Koenderink, 1999;Zuidhoek, Kappers, van der Lubbe, & Postma, 2003, Zuidhoek et al., 2004). An egocentric reference frame presupposes coding of the locations and spatial orientations of items in the outside world with respect to a part of one's body, such as the hands, the midsagittal plane (Zuidhoek, Kappers, & Postma, 2005), the body as a whole (Heller, Calcaterra, Green, & Barnette, 1999), or a subjective gravitational frame (Luyat, Gentaz, Corte, & Guerraz, 2001). In an allocentric reference frame, spatial information is encoded with respect to external landmarks in the outside world, such as when taking into account the available surrounding background information (Millar, 1988(Millar, , 1994Thinus-Blanc & Gaunet, 1997). The first phase of haptic processing might almost obligatorily involve the employment of an ego-or bodycentered reference frame. It should be noted that in the Early-blind, late-blind, and blindfolded sighted participants were presented with two haptic allocentric spatial tasks: a parallel-setting task, in an immediate and a 10-sec delay condition, and a task in which the orientation of a single bar was judged verbally. With respect to deviation size, the data suggest that mental visual processing filled a beneficial role in both tasks. In the parallel-setting task, the early blind performed more variably and showed no improvement with delay, whereas the late blind did improve, but less than the sighted did. In the verbal judgment task, both early-and late-blind participants displayed larger deviations than the sig...

The effect of vertical and horizontal symmetry on memory for tactile patterns in late blind individuals

“…In fact, visual imagery has been found to play a critical role in mediating tactile perception and recognition in normally sighted individuals (see Lacey et al, 2010, Scocchia et al, 2009), as also is suggested by the involvement of the occipital cortex in haptic discrimination (e.g., Merabet et al, 2007, Merabet et al, 2004). Accordingly, different studies suggest that prior visual experience can be used by the late blind to support their haptic and auditory perception, thereby helping them to generate a mental representation of the surrounding environment (e.g., Alary et al, 2008, Postma, Zuidhoek, Noordzij, & Kappers, 2008, Vanlierde & Wanet-Defalque, 2004). …”

Crossmodal interaction between the mental number line and peripersonal haptic space representation in sighted and blind individuals

“…Conversely, a large number (8) shifted the per-Since the rods were positioned centrally to the midline of the participants, it cannot be excluded that both blind and sighted individuals relied on a body-centered representation of space in performing the task, using their body midline as a reference for distance judgments. Previous studies suggest that blind individuals rely on egocentric space representation in perception of near space (see Gaunet & Rossetti, 2006;Postma, Zuidhoek, Noordzij, & Kappers, 2008), whereas sighted individuals tend to shift from an egocentric reference frame to an allocentric reference frame after a few seconds (see Rossetti, 1998;Rossetti & Pisella, 2002;Rossetti & Régnier, 1995;Zuidhoek, Kappers, van der Lubbe, & Postma, 2003), and it has been demonstrated that the adoption of an egocentric versus an allocentric spatial reference frame may modulate the direction of numerical magnitude representation (e.g., Conson, Mazzarella, & Trojano, 2009). On the basis of our findings, it is not possible to disentangle whether the rods' lengths were encoded into an egocentric or an allocentric reference frame; what is critical is that the mental number line was found to modulate the perception of haptic space in a crossmodal fashion.…”

The Impact of Early Visual Deprivation on Spatial Hearing: A Comparison between Totally and Partially Visually Deprived Children

“…Despite the effort in including all the results reported on the topic in a single comprehensive theory, to date the role of visual input in the development of spatial cognition is still unclear due to the high controversy of the results supporting the mentioned scientific hypotheses. The cross-sensory calibration hypothesis proposed by Gori et al (2008, 2014) and supported by experimental data (Postma et al, 2008; Cappagli et al, 2015; Finocchietti et al, 2015; Vercillo et al, 2016) attempts to provide a comprehensive explanation by stating that during the early development vision calibrates other senses to process spatial information because vision is the most robust sense to perceive the spatial properties of the world. The spatial properties of the surrounding environment are indeed best discovered with vision because it provides an immediate and complete representation of multiple and simultaneous stimuli in the environment (Thinus-Blanc and Gaunet, 1997).…”