It is still unclear how the visual system perceives accurately the size of objects at different distances. One suggestion, dating back to Berkeley's famous essay, is that vision is calibrated by touch. If so, we may expect different mechanisms involved for near, reachable distances and far, unreachable distances. To study how the haptic system…

A map exploration and representation exercise was conducted with participants who were totally blind. Representations of maritime environments were presented either with a tactile map or with a digital haptic virtual map. We assessed the knowledge of spatial configurations using a triangulation technique. The results revealed that both types of…

The integrated use of spatial and temporal information seems to support the separation of two sensory streams. The present study tested whether this facilitation depends on the encoding of sensory stimuli in externally anchored spatial coordinate systems. Fifty-nine children between 5 and 12 years as well as 12 young adults performed a crossmodal…

The study reported here investigated the design and legibility of tactile thematic maps, focusing on symbolization and the comprehension of spatial patterns on the maps. The results indicate that discriminable and effective tactile thematic maps can be produced using classed data with a microcapsule paper production method. The participants…

The relations between reading, auditory, speech, phonological and tactile spatial processing are investigated in a Dutch speaking sample of blind braille readers as compared to sighted print readers. Performance is assessed in blind and sighted children and adults. Regarding phonological ability, braille readers perform equally well compared to…

Many studies invoke moment of inertia (I[subscript ii]) as necessary and sufficient information to perceive cylinder length via wielding, yet some assert that I[subscript ii] is neither necessary (weight, "m", or static moment, M, are sufficient) nor sufficient for length judgments ("m" or M is necessary). Mathematical expressions for I[subscript…

Negative priming (NP) refers to the finding that people's responses to probe targets previously presented as prime distractors are usually slower than to unrepeated stimuli. Intriguingly, the effect sizes of tactile NP were much larger than the effect sizes for visual NP. We analyzed whether the large tactile NP effect is just a side effect of the…

Preschoolers who explore objects haptically often fail to recognize those objects in subsequent visual tests. This suggests that children may represent qualitatively different information in vision and haptics and/or that children's haptic perception may be poor. In this study, 72 children (2 1/2-5 years of age) and 20 adults explored unfamiliar…

Adults vary their haptic exploratory behavior reliably with variation both in the sensory input and in the task goals. Little is known about the development of these connections between perceptual goals and exploratory behaviors. A total of 36 children ages 3, 4, and 5 years and 20 adults completed a haptic intramodal match-to-sample task.…

The objective of the present study was to assess the development of luminance- and texture-defined static form perception in school-aged children. This was done using an adapted Landolt-C technique where C-optotypes were defined by either luminance or texture information, the latter necessitating extra-striate neural processing to be perceived.…

Social interactions within virtual communities are often described solely as being online experiences. Such descriptions are limited, for they fail to reference life external to the screen. The terms "virtual" and "real" have a negative connotation for many people and can even be interpreted to mean that something is "false" or "inauthentic."…

This study shows that in a novel task--bimanual haptic tracking--neurologically normal human adults can move their 2 hands independently for extended periods of time with little or no training. Participants lightly touched buttons whose positions were moved either quasi-randomly in the horizontal plane by 1 or 2 human drivers (Experiment 1), in…

After haptic habituation to a ring display, infants perceived the rings in two experiments as parts of one connected object. In both haptic and visual modes, infants appeared to perceive object unity by analyzing motion but not by analyzing figural goodness. (RH)

Exploring the ability of subjects to make accurate discriminations by active touch, two studies involving 20 sighted adults investigated sensitivity of the fingertip in perceiving length, using Braille cells as stimuli. Results indicated differential sensitivity of the fingertip to one parameter of active touch: cell height discrimination. (JW)

All Ss' accuracy decreased with increasing task difficulty. Accuracy of nonretarded Ss did not differ as a function of visual status. Blind retarded Ss were more accurate than were sighted retarded Ss. (Author)