The influence of restricted viewing conditions on egocentric distance perception: implications for real and virtual indoor environments

We carried out three experiments to examine the influence of field of view and binocular viewing restrictions on absolute distance perception in real-world indoor environments. Few of the classical visual cues provide direct information for accurate absolute distance judgments to points in the environment beyond about 2 m from the viewer. Nevertheless, in previous work it has been found that visually directed walking tasks reveal accurate distance estimations in full-cue real-world environments to distances up to 20 m. In contrast, the same tasks in virtual environments produced with head-mounted displays (HMDs) show large compression of distance. Field of view and binocular viewing are common limitations in research with HMDs, and have been rarely studied under full pictorial-cue conditions in the context of distance perception in the real-world. Experiment 1 showed that the view of one's body and feet on the floor was not necessary for accurate distance perception. In experiment 2 we manipulated the horizontal and the vertical field of view along with head rotation and found that a restricted field of view did not affect the accuracy of distance estimations when head movement was allowed. Experiment 3 showed that performance with monocular viewing was equal to that with binocular viewing. These results have implications for the information needed to scale egocentric distance in the real-world and reduce the support for the hypothesis that a limited field of view or imperfections in binocular image presentation are the cause of the underestimation seen with HMDs.     

Paired-associate learning, phoneme awareness, and learning to read

We report two studies examining the relations among three paired-associate learning (PAL) tasks (visual-visual, verbal-verbal, and visual-verbal), phoneme deletion, and single-word and nonword reading ability. Correlations between the PAL tasks and reading were strongest for the visual-verbal task. Path analyses showed that both phoneme deletion and visual-verbal PAL were unique predictors of a composite measure of single-word reading and of irregular word reading. However, for nonword reading, phoneme deletion was the only unique predictor (and visual-verbal PAL was not a significant predictor). These results are consistent with the view that learning visual (orthography) to phonological mappings is an important skill for developing word recognition skills in reading and that individual differences in this ability can be tapped experimentally by a PAL task.     

Cognitive marriage counseling with acutely disturbed in-patients

1980 edition ofThe Diagnostic and Statistical Manual of Mental Disorders III suggests that there is a deleterious interaction between Axes I psychiatric disorders and Axes IV psychosocial stressors such as marital disharmony. With acutely disturbed in-patients, marital problems are often found associated with the psychiatric disorder, but they are usually not treated until after the patient has been discharged to out-patient status. Offering concurrent treatment for both the Axes I disorder and the Axes IV stressors would seem to be a move in the direction of a more efficient and a more comprehensive treatment plan. A ten-session course of marriage counseling based on cognitive theory is now being offered to hospitalized psychiatric patients in a rural Veterans Administration Medical Center. The model does not propose to resolve all marital problems in therapy. The goal is to teach the hospitalized patient and their spouse cognitive principles that will enable them to more effectively resolve their own problems after the patient is discharged. It is anticipated that the cognitive principles learned in marriage counseling will also apply to the resolution of some of the problems associated with the psychiatric disorder. Thus the treatment for the Axes IV stressor enhances the treatment for the Axes I psychiatric disorder. This approach might well shorten the patients' hospitalization and reduce the risk of relapse after discharge. Preliminary results suggest that this course shows promise for both individual and marital adjustment.He holds a Primary Certificate with The Institute for Rational-Emotive Therapy, and is working on his Doctorate in Social Work at The Catholic University of America, Washington, D.C.     

Are the literacy difficulties that characterize developmental dyslexia associated with a failure to integrate letters and speech sounds?

The ‘automatic letter‐sound integration hypothesis’ (Blomert, 2011 ) proposes that dyslexia results from a failure to fully integrate letters and speech sounds into automated audio‐visual objects. We tested this hypothesis in a sample of English‐speaking children with dyslexic difficulties (N = 13) and samples of chronological‐age‐matched (CA; N = 17) and reading‐age‐matched controls (RA; N = 17) aged 7–13 years. Each child took part in two priming experiments in which speech sounds were preceded by congruent visual letters (congruent condition) or Greek letters (baseline). In a behavioural experiment, responses to speech sounds in the two conditions were compared using reaction times. These data revealed faster reaction times in the congruent condition in all three groups. In a second electrophysiological experiment, responses to speech sounds in the two conditions were compared using event‐related potentials (ERPs). These data revealed a significant effect of congruency on (1) the P1 ERP over left frontal electrodes in the CA group and over fronto‐central electrodes in the dyslexic group and (2) the P2 ERP in the dyslexic and RA control groups. These findings suggest that our sample of English‐speaking children with dyslexic difficulties demonstrate a degree of letter‐sound integration that is appropriate for their reading level, which challenges the letter‐sound integration hypothesis.     

Perceiving virtual geographical slant: action influences perception

In 4 experiments, the authors varied the extent and nature of participant movement in a virtual environment to examine the influence of action on estimates of geographical slant. Previous studies showed that people consciously overestimate hill slant but can still accurately guide an action toward the hill (D. R. Proffitt, M. Bhalla, R. Gossweiler, & J. Midgett, 1995). Related studies suggest that one's potential to act may influence perception of slant and that distinct representations may independently inform perceptual and motoric responses. The authors found that in all conditions, perceptual judgments were overestimated and motoric adjustments were more accurate. The virtual environment allowed manipulation of the effort required to walk up simulated hills. Walking with the effort appropriate to the visual slant led to increased perceptual overestimation of slant compared with active walking with the effort appropriate to level ground, while visually guided actions remained accurate.     

Evidence for Age-related Changes to Temporal Attention and Memory from the Choice Time Production Task

ABSTRACT

The effect of aging on interval timing was examined using a choice time production task, which required participants to choose a key response based on the location of the stimulus, but to delay responding until after a learned time interval. Experiment 1 varied attentional demands of the response choice portion of the task by varying difficulty of stimulus–response mapping. Choice difficulty affected temporal accuracy equally in both age groups, but older participants' response latencies were more variable under more difficult response choice conditions. Experiment 2 tested the contribution of long-term memory to differences in choice time production between age groups over 3 days of testing. Direction of errors in time production between the two age groups diverged over the 3 sessions, but variability did not differ. Results from each experiment separately show age-related changes to attention and memory in temporal processing using different measures and manipulations in the same task.