Vision and touch: A reconsideration of conflict between the two senses.

Although many studies have supported I. Rock and J. Victor's (see record 1964-07119-001) conclusion that visual-tactual conflicts will be resolved in favor of vision, the present study with 30 undergraduates presents evidence that methodological problems may have produced a bias in favor of vision. An experimental group examined blocks of wood of several sizes both visually and tactually, while 2 control groups examined the blocks by either vision or touch alone. After exposure to each block, Ss selected a comparison block of equal size from a set of 15 blocks. Group means indicate that experimental Ss made a judgment which was a compromise between their visual and tactual impressions. Closer examination showed that Ss made their judgments conform to either their visual or tactual impressions, and that there was great heterogeneity of response pattern. Results indicate that the generalization of vision as a dominant modality may be premature. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory dominance in temporal processing: New evidence from synchronization with simultaneous visual and auditory sequences.

Evidence that audition dominates vision in temporal processing has come from perceptual judgment tasks. This study shows that this auditory dominance extends to the largely subconscious processes involved in sensorimotor coordination. Participants tapped their finger in synchrony with auditory and visual sequences containing an event onset shift (EOS), expected to elicit an involuntary phase correction response (PCR), and also tried to detect the EOS. Sequences were presented in unimodal and bimodal conditions, including one in which auditory and visual EOSs of opposite sign coincided. Unimodal results showed greater variability of taps, smaller PCRs, and poorer EOS detection in vision than in audition. In bimodal conditions, variability of taps was similar to that for unimodal auditory sequences, and PCRs depended more on auditory than on visual information, even though attention was always focused on the visual sequences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Haptic exploration in the presence of vision.

Two experiments addressed initiation of haptic exploration to encode object properties when vision is present. Ss compared pairs of objects on designated properties, using only vision or with touch permitted. Touch initiation, reach, contact, and visual responses were timed. With difficult material judgments, touch occurred frequently and was initiated faster than the time to respond by vision alone. With geometric judgments, touch was rarely used and then was initiated at the typical time for a visual response. Imposing a visual preview before allowing touch did not reduce the incidence of touch but did speed its initiation. Results support a model in which preliminary visual processing quickly initiates haptic exploration for material judgments that are visually or semantically difficult. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of perceptual load on attention-induced motion blindness: The efficiency of selective inhibition.

Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of "cognitive" and "perceptual" load. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Hemispheric asymmetry in the visual contribution to postural control in healthy adults

This study was carried out in order to test the hypothesis of a right hemisphere dominance in the visual control of body balance. Eight healthy adults were subjected to a self-regulated lateral balance task, performed while sitting on a rocking platform. Four visual conditions were tested: open eyes with normal vision, closed eyes in the dark, left visual field-right hemisphere and right visual field-left hemisphere. Head and support displacements in the roll plane were recorded by means of an optoelectronic system. Two main results emerged from this study: (1) head stabilization in space was much more efficient in the left visual field-right hemisphere condition than in the three other visual conditions, and (2) although vision played an important role in the body stability whatever the anatomical level, there was no right hemisphere dominance at the pelvic level. A clear right hemisphere dominance was thus demonstrated as regards the visual contribution to head stabilization in space.     

The characteristics of the color perceptive space in protanomals

Color vision of three protanomal subjects was studied by means of direct paired comparison technique using 25 colors with different brightness. It was shown that the characteristics of their color vision could be completely and adequately described in the frames of the four-dimensional spherical model of color perception. The spatial axes could be identified as the two color-opponent mechanisms (red-green and blue-yellow) and the two achromatic mechanisms (brightness and darkness). Deformation of the color axes in protanomals (as compared with the normal trichromatics) was demonstrated in the "red" and "yellow" spectral region. The visual disturbance in protanomal subjects involves not only color but also achromatic mechanisms. This is manifested in the a deformation of perceptual brightness scale. In comparison with normal trichromatic subjects, the protanomals perceive the red and adjacent colors as achromatic while green, yellow-green, and orange as more bright but low-saturated colors.     

Perception of texture by vision and touch: Multidimensionality and intersensory integration.

Six experiments, with 224 university students and staff, indicate that there is no fixed dominance hierarchy for the perception of textured patterns and highlight the importance of recognizing the multidimensionality of texture perception. The relative bias between vision and touch was reversed or considerably altered using both discrepancy and nondiscrepancy paradigms. This shift was achieved merely by directing Ss to judge different dimensions of the same textured surface. Exps I, IV, and V showed relatively strong emphasis on visual as opposed to tactual cues regarding the spatial density of raised dot patterns. In contrast, Exps II, III, and VI demonstrated considerably greater emphasis on the tactual as opposed to visual cues when Ss were instructed to judge the roughness of the same surfaces. The results are discussed in terms of a modality appropriateness interpretation of intersensory bias. A weighted average model appeared to described the nature of the intersensory integration process for both spatial density and roughness perception. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Changes of auditory word discrimination induced by inversion of the visual field.

Examined auditory discrimination in normal hospital staff members during induced visual conflict. Discrimination of words accompanied by background noise was measured at 6 speech-signal-noise intensity levels during preexperimental (normal vision), experimental (inverted vision), and postexperimental (normal vision) periods. A control condition (no inverted vision) served as a check for the possible effects of practice or fatigue. Significant losses of word discrimination occurred only in the inverted vision condition. Discrimination losses occurred at all intensity levels in which speech was accompanied by noise, prior to walking in the inverted vision condition, following a walking period, and after removal of inversion eyepieces. Results are attributed to a process of visually induced conflict in which Ss were unable to decenter the altered contents of vision. Affinities between reports of induced alterations of experience and pathological alterations of experience are discussed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neural plasticity in adults with amblyopia

Amblyopia is a neuronal abnormality of vision that is often considered irreversible in adults. We found strong and significant improvement of Vernier acuity in human adults with naturally occurring amblyopia following practice. Learning was strongest at the trained orientation and did not transfer to an untrained task (detection), but it did transfer partially to the untrained eye (primarily at the trained orientation). We conclude that this perceptual learning reflects alterations in early neural processes that are localized beyond the site of convergence of the two eyes. Our results suggest a significant degree of plasticity in the visual system of adults with amblyopia.     

How visual imagery interferes with vision.

Mental visual imagery interferes with vision: the Perky (1910) effect. Is the effect optical, sensory, perceptual, attentional, or just a response bias? Acuity was measured (in undergraduates and graduates) using target lines, with and without images (of lines). Optics (fixation, pupil size, accommodation), response bias, global attention (effort, diversion of attention to imagery), perceptual assimilation (target incorporation by imagery) and perceptual masking (of target by imagery) all fail to explain the effect. Foveally, local attention plays a limited role, as the Perky effect in divided attention is half that in focused attention, but this interaction vanishes with extrafoveal targets. Images produce primarily sensory interference, mimicking a reduction in target energy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Not only in the eye of the beholder: Tactile information can affect aesthetic evaluation.

The study tested if evaluation of Aesthetic quality is influenced by tactile information and whether the evaluation process is affected more by one modality (vision) than another (touch). Tactile sensing and visual appreciation were compared with combined visual and tactile sensing of surface textures. Three kinds of plastic textures on the outside of a DVD container and three sample swatches of the textures used on the DVDs were used in the study. Three DVD containers were presented visually to the participants. This was followed by a blind haptic evaluation (i.e., the participants could only feel but not see the swatches) of the three different textured swatches, and then by combined visual and tactile evaluation of the three differently textured DVDs. One hundred and twelve participants took part in all 3 evaluations. A regression analysis showed that in 2 of the 3 conditions tested, overall Aesthetic evaluation was influenced both by vision and touch. To what extent the modalities influenced the evaluation depended upon which of the textures had been evaluated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Translating visual art into tactile art to produce equivalent aesthetic experiences.

An argument is put forward to show that visual art may actually be translated into tactile objects that produce equivalent aesthetic experiences for blind or visually impaired people. This is shown by delineating the information required for such a translation in general, demonstrating that such a translation is already achievable from color vision to color vision and theoretically possible from spatial vision to spatial touch, and outlining that an analogous procedure could be applied to aesthetic experience. Limitations of such translations of visual works of art into tactile objects, and implications of such a procedure for artistic experience and education, are also mentioned. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dominance of global visual properties at birth.

Six experiments are reported that were aimed at demonstrating the presence in newborns of a perceptual dominance of global over local visual information in hierarchical patterns, similar to that observed in adults (D. Navon, 1977, 1981). The first four experiments showed that, even though both levels of visual information were detectable by the newborn (Experiments 1A and 1B), global cues enjoyed some advantage over local cues (Experiments 2 and 3). Experiments 4A and 4B demonstrated that the global bias was strictly dependent on the low spatial frequency content of the stimuli and vanished after selective removal of low spatial frequencies. The results are interpreted as suggesting parallels between newborns' visual processing and processing later in development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Postattentive vision.

Much research has examined preattentive vision: visual representation prior to the arrival of attention. Most vision research concerns attended visual stimuli; very little research has considered postattentive vision. What is the visual representation of a previously attended object once attention is deployed elsewhere? The authors argue that perceptual effects of attention vanish once attention is redeployed. Experiments 1–6 were visual search studies. In standard search, participants looked for a target item among distractor items. On each trial, a new search display was presented. These tasks were compared to repeated search tasks in which the search display was not changed. On successive trials, participants searched the same display for new targets. Results showed that if search was inefficient when participants searched a display the first time, it was inefficient when the same, unchanging display was searched the second, fifth, or 350th time. Experiments 7 and 8 made a similar point with a curve tracing paradigm. The results have implications for an understanding of scene perception, change detection, and the relationship of vision to memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual organization and schizotypy.

The preattentive visual information processing of hypothetically psychosis-prone college Ss was evaluated using 3 different paradigms: target detection (n?=?57), visual suffix effect (n?=?57), and configural superiority effect (n?=?68). It was hypothesized that anhedonic Ss would show the same perceptual organization deficits reported in process schizophrenics and that perceptual aberration-magical ideation Ss and depressed Ss would perform similarly to control Ss. In each study, anhedonics performed similarly to each comparison group, even though there was adequate power to detect performance differences if they existed. A framework for understanding the visual information-processing deficits of schizophrenics and high-risk Ss is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceptual and motor inhibition in adolescents/young adults with childhood-diagnosed ADHD.

Objective: This study examined perceptual and motor inhibition in a longitudinal sample of adolescents/young adults who were diagnosed with ADHD in childhood, and as a function of the relative persistence of ADHD. Method: Ninety-eight participants diagnosed with ADHD in childhood were reevaluated approximately 10 years later. Eighty-five never-ADHD controls similar in age, IQ, sociodemographic background, and gender distribution served as a comparison group. Participants were administered a psychiatric interview and the Stimulus and Response Conflict Tasks (Nassauer & Halperin, 2003). Results: Participants with childhood ADHD demonstrated slower and less accurate responses to both control and conflict conditions relative to the comparison group, as well as more variable responses in both conditions of the motor inhibition task; there was no specific effect of childhood ADHD on perceptual or motor inhibition. ADHD persisters and partial remitters did not differ in overall accuracy, speed or variability in responding, but relative to partial remitters, persisters demonstrated greater slowing in response to perceptual conflict. Conclusions: These findings are consistent with theories positing state regulation, but not inhibitory control deficits in the etiology of ADHD, and suggest that improved perceptual inhibition may be associated with better outcome for ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Patchy distribution of NMDAR1 subunit immunoreactivity in developing visual cortex

Development of ocular dominance columns is dependent on patterned retinal activity, and yet patterned activity alone cannot explain all aspects of cortical column development. Features intrinsic to the cortex have been proposed to interact with activity to guide the patterning of cortical columns (), and the NMDA receptor, because of its role in experience-dependent plasticity, is an obvious candidate. Using immunohistochemical techniques, we found a transiently patchy distribution of the NMDA receptor 1 (NMDAR1) subunit in kitten visual cortex. Regularly spaced patches of NMDAR1-immunoreactive neurons were found at the top of the cortical plate in the developing visual cortex at 2 weeks of age. At 4-5 weeks of age, the radial extent of the NMDAR1 patches spanned the supragranular layers, and by 12 weeks of age, this nonuniform pattern of NMDAR1 immunostaining was no longer apparent. Monocular visual experience prevented the expression of the NMDAR1 patches, but just 4 d of subsequent binocular visual experience was sufficient to promote expression of the patches. Furthermore, the NMDAR1 patches tended to be associated with the borders of ocular dominance columns. These results suggest that the degree of plasticity associated with NMDA-mediated mechanisms is elevated in local regions across the tangential extent of the visual cortex and that the NMDAR1 patches may participate in sculpting the overall arrangement of visual cortical columns.     

Age differences and similarities in patterns of cerebral hemispheric asymmetry.

Younger (M age?=?20.4 years) and older (M age?=?70.7 years) adults participated in 3 visual half-field experiments. These were designed to examine specific aspects of hemispheric asymmetry: (a) hemispheric dominance for phonetic–linguistic processing (as measured by identification of nonword trigrams), (b) hemispheric differences in trigram processing strategy, (c) characteristic perceptual biases thought to reflect hemispheric arousal asymmetries, and (d) hemispheric dominance for processing emotions shown on faces. Patterns of left–right asymmetries were comparable for older and younger participants, and intercorrelations among the various measures of asymmetry were similar for both groups. In view of the present results, it seems unlikely that changes in hemispheric asymmetry contribute significantly to age-related changes in cognitive functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The shape of self-motion perception--I. Equivalence classification for sustained motions

Two completely different motions of a subject relative to the earth can induce exactly the same stimuli to the vestibular, somatosensory and visual systems. When this happens, the subject may experience disorientation and misperception of self-motion. We have identified large classes of motions that are perceptually equivalent, i.e. indistinguishable by the subject, under three sets of conditions: no vision, with vision and earth-fixed visual surround, and with vision during possible movement of the visual surround. For each of these sets of conditions, we have developed a classification of all sustained motions according to their perceptual equivalences. The result is a complete list of the possible misperceptions of sustained motion due to equivalence of the forces and other direct stimuli to the sensors under the given conditions. This research expands the range of possible experiments by including all components of linear and angular velocity and acceleration. Many of the predictions in this paper can be tested experimentally. In addition, the equivalence classes developed here predict perceptual phenomena in unusual motion environments that are difficult or impossible to investigate in the laboratory.