Information loss: the primary psychological trauma of the loss of vision.

A psychology of blindness is proposed that contends that information loss is the most critical trauma of the loss of vision. The magnitude of information loss is emphasized with respect to vision as the primary sensory modality for obtaining information. Further, the vital role of access to information in human development and the tendency to seek information to cope with stressful circumstances are addressed. Implications for rehabilitation of blind persons are discussed.     

Weekends and holidays and acting-out behavior of developmentally delayed women: a reply to Dr. Mark Flynn.

A previous report on the effect of the day of the full moon on the acting-out behavior of 20 developmentally delayed, institutionalized women showed that on the day of the full moon there were significantly more misbehaviors than on any other day during the lunar period. The records were re-evaluated to assess the frequency of acting-out behaviors on weekends and holidays as contrasted with the balance of the month. This re-evaluation indicated there was no significant difference between the weekends and holidays and the balance of the month (t = 1.14). The results were taken as support of the previous findings that on the day of the full moon there were significantly more misbehaviors than on any other day of the lunar period.     

THE INFLUENCE OF ASSESSEE PERFORMANCE VARIATION ON ASSESSORS'JUDGMENTS

Assessors evaluated assessees'performances in one of three performance conditions in an assessment center simulation: a consistent performance condition, a within-assessee performance variation condition, or a between-assessee performance variation condition. Contrast effects influenced ratings of assessees when there was variation in performance within assessees. For each assessee, the low target performance was rated lower when the assessee's prior performance had been dissimilar (high) than when the assessee's prior performance had been similar (low). Contrast effects also infiuenced assessors'ratings of the target assessee when there was variation in performance among assessees. The low performing target assessee was rated significantly lower when he was evaluated with two high performers than when he was evaluated with two low performers. In addition, ratings obtained when there was performance variation among assessees were more accurate than those obtained when there was no performance variation, suggesting that under some circumstances contrast effects may not lead to inferior judgments.     

INTERVIEWER DECISION PROCESSES AND EFFECTIVENESS: AN EXPERIMENTAL POLICY-CAPTURING INVESTIGATION

Using a policy-capturing approach, 29 corporate interviewers evaluated 64 hypothetical candidates for a position in a financial services organization. Six selection criteria were manipulated in a balanced factorial design. Interviewers evaluated candidates' qualifications and made hiring recommendations. The results revealed substantial individual differences in interviewers' decision strategies, as well as their insight into their own decision processes. Data on the effectiveness of the 29 interviewers were collected from 427 hiring managers and the decision processes of effective and ineffective interviewers were compared. The findings indicated that the decision strategies used by effective interviewers were quite similar to one another and relied heavily on two selection criteria. Also, effective interviewers were more likely than ineffective interviewers to use selection criteria in a manner that mirrored their self-reports of the importance of these criteria. Effective interviewers were more aware of their decision processes than ineffective interviewers.     

Metacognition in psychophysical judgment: an unfolding view of comparative judgments of mental workload.

An experiment is reported in which it was found that when subjects were required to indicate which of two visual extents was more difficult to categorize as "long" or "short," they executed these categorizations and then measured the distance of the representation of each stimulus from the long-short category boundary; the stimulus nearer the boundary was judged to be the more difficult. When they were requested to indicate which was easier to categorize, they selected the alternative that was farther. Coombs's theory of data (1952, 1964) and his unfolding theory of preferential choice (1950, 1964) provided the conceptualization of metacognition in this psychophysical task context. Strong support for the probabilistic version of unfolding theory was obtained from the observed selective effects of laterality on the levels of stochastic transitivity attained for various classes of triples and the reliably longer times for comparisons with bilateral pairs than with unilateral pairs. The semantic congruity effects obtained, together with the changes in the form of the relationship between probability and response time as a function of practice, can be best accounted for by an evidence accrual theory in which the distances from the active reference point are measured and compared with a criterion on each evidence accrual. No support is provided for the view that propositionally based semantic "ease"-"difficulty" codes serve as the basis for these metacognitive comparative judgments of ease and difficulty.     

Extracting thresholds from noisy psychophysical data.

Psychophysical studies with infants or with patients often are unable to use pilot data, training, or large numbers of trials. To evaluate threshold estimates under these conditions, computer simulations of experiments with small numbers of trials were performed by using psychometric functions based on a model of two types of noise: stimulus-related noise (affecting slope) and extraneous noise (affecting upper asymptote). Threshold estimates were biased and imprecise when extraneous noise was high, as were the estimates of extraneous noise. Strategies were developed for rejecting data sets as too noisy for unbiased and precise threshold estimation; these strategies were most successful when extraneous noise was low for most of the data sets. An analysis of 1,026 data sets from visual function tests of infants and toddlers showed that extraneous noise is often considerable, that experimental paradigms can be developed that minimize extraneous noise, and that data analysis that does not consider the effects of extraneous noise may underestimate test-retest reliability and overestimate interocular differences.     

A generalized visual latency explanation of the Pulfrich phenomenon.

The classical visual latency explanation of the Pulfrich phenomenon is generalized to allow for the possibility that the visual system uses velocity information from motion detectors to compensate for spatial lag due to time lag, in identifying the instantaneous position of a moving object. The results of the reported experiment verify one consequence of the generalized version: the elliptical apparent path is skewed away from the filtered eye. The results suggest also that the extrapolation factor increases with visual latency and that there is a different extrapolation factor for each eye when the eyes are illuminated unequally.     

Haptic probing: perceiving the length of a probe and the distance of a surface probed.

Knowing about the properties of objects by wielding them and knowing about the distances of surfaces by striking them with objects as probes are examples of dynamic or effortful touch. Six experiments focused on the invariant mechanical parameters that couple the time-varying states (displacements, velocities) of hand-held rods to the time-varying torques and forces imposed upon them by wielding and probing. There were three major conclusions. First, when a probe is wielded without contact, perceived probe length is a function of the probe's rotational inertia; however, with contact, perceived probe length is affected by the rotational inertia and the distance of the point of contact from the probe's center of percussion. Second, when a surface is struck with a probe, perceived surface distance is affected by the probe's rotational inertia and the angle of inclination of the probe at contact. Third, under seemingly identical conditions of probing, either probe length or surface distance can be perceived selectively without confusion. Results were discussed in terms of haptic information, haptic attention, and the dynamics of probing.     

Relationships among age, sex, and depth of sport experience with initial open-task performance by 4- to 9-year-old children.

The purpose of this study was to assess the relative interrelationships of age, sex, and depth of sport experience on initial practice of a soccer task for 46 4- to 9-yr.-old children. Each child practiced 1 transfer trial and 3 blocks of 3 trials. Measures recorded were performance time, goal attainment, and movement accuracy. Multivariate analyses of variance and multiple regressions yielded evidence for (a) a speed-accuracy tradeoff, (b) a relation of age to goal attainment, movement accuracy, and performance time on the transfer trial, and (c) a relation of age with Block 1 performance time. Experience was more related than sex to all variables except movement accuracy in Block 1 and consistency of goal attainment. Conclusions are that age and experience are the most important to the quality of performance, and no constructs were related to consistency on this task for this age group.     

A novel contact-lens system to assess visual hemispheric asymmetries.

A soft contact-lens system for achieving unilateral visual stimulation in a free vision format is described. Initial testing with light transmittance and visual perimetry indicated that the lenses created artificial visual-field deficits. The efficacy of the lenses as a technique for lateralizing visual input was evaluated by examining within-subject differences in performance on two visuospatial tasks. Speed and accuracy of performance were greater with visual input directed to the right hemisphere. These data support the lens design as a useful alternative to tachistoscopic procedures and previous lens systems.