Perceived duration of expected and unexpected stimuli

Three experiments assessed whether perceived stimulus duration depends on whether participants process an expected or an unexpected visual stimulus. Participants compared the duration of a constant standard stimulus with a variable comparison stimulus. Changes in expectancy were induced by presenting one type of comparison more frequently than another type. Experiment 1 used standard durations of 100 and 400 ms, and Experiments 2 and 3 durations of 400 and 800 ms. Stimulus frequency did not affect perceived duration in Experiment 1. In Experiments 2 and 3, however, frequent comparisons were perceived as shorter than infrequent ones, and discrimination performance was better for infrequent comparisons. Overall, this study supports the notion that infrequent stimuli increase the speed of an internal pacemaker.     

Perception of auditory motion affects language processing

Previous reports have demonstrated that the comprehension of sentences describing motion in a particular direction (toward, away, up, or down) is affected by concurrently viewing a stimulus that depicts motion in the same or opposite direction. We report 3 experiments that extend our understanding of the relation between perception and language processing in 2 ways. First, whereas most previous studies of the relation between perception and language processing have focused on visual perception, our data show that sentence processing can be affected by the concurrent processing of auditory stimuli. Second, it is shown that the relation between the processing of auditory stimuli and the processing of sentences depends on whether the sentences are presented in the auditory or visual modality.     

Are Developmental Pathways in Disruptive Behaviors the Same for Girls and Boys?

Data from the first five waves of the National Youth Survey were used to test the applicability of the Developmental Pathways model to a nationally representative sample of girls. Overall, girls were less likely to be involved in all types of delinquent behavior, with the majority of girls reporting no delinquent involvement across the five waves of data collected. Using the Developmental Pathways model, similar developmental patterns of antisocial and delinquent involvement were found for girls as have been found for boys. Approximately 70% of involved girls followed most steps in each of the pathways. We also evaluated the relation of family and peer factors to specific pathways and found differences in those relations for boys and girls. For girls, only parental monitoring was related to involvement in one of the three pathways. For boys, specific relations were found between family and peer variables and each of the three developmental pathways. As with previous studies on girls involvement in disruptive behavior, these results suggest some general consistency in patterns with that of boys, although differences in frequency and predictors of risk.     

Exploring "fringe" consciousness: the subjective experience of perceptual fluency and its objective bases

Perceptual fluency is the subjective experience of ease with which an incoming stimulus is processed. Although perceptual fluency is assessed by speed of processing, it remains unclear how objective speed is related to subjective experiences of fluency. We present evidence that speed at different stages of the perceptual process contributes to perceptual fluency. In an experiment, figure-ground contrast influenced detection of briefly presented words, but not their identification at longer exposure durations. Conversely, font in which the word was written influenced identification, but not detection. Both contrast and font influenced subjective fluency. These findings suggest that speed of processing at different stages condensed into a unified subjective experience of perceptual fluency.     

The role of age and perceptual symbols in language comprehension

Older and younger participants read sentences about objects and were then shown a picture of an object that either matched or mismatched the implied shape of the object in the sentence. Participants' response times were recorded when they judged whether the object had been mentioned in the sentence. Responses were faster in the shape-matching condition for all participants, but the mismatch effect was stronger for older than for younger adults, even when the larger variability of the older group's response times was controlled for. These results suggest that older adults may construct stronger situation models than younger adults.     

Primed word-fragment completion and successive memory test performance in normal aging

Young and old subjects were investigated to examine whether: the effects of priming are influenced by aging; there is independence between primed word-fragment completion and recognition performances; and the dependence between different tests is influenced by aging. A successive test paradigm was employed involving repeated assessment of to-be-remembered words by means of recognition and primed word-fragment completion. The results show that implicit memory declines with increasing age, and that correlations between different memory tests decrease with age. The outcome suggests that age-related memory decline involves several forms of memory, including primed word-fragment completion, and is reflected in correlations between measures of implicit and explicit memory.     

Directed attention prolongs the perceived duration of a brief stimulus

Stelmach, Herdman, and McNeil (1994) suggested recently that the perceived duration for attended stimuli is shorter than that for unattended ones. In contrast, the attenuation hypothesis (Thomas & Weaver, 1975) suggests the reverse relation between directed attention and perceived duration. We conducted six experiments to test the validity of the two contradictory hypotheses. In all the experiments, attention was directed to one of two possible stimulus sources. Experiments 1 and 2 employed stimulus durations from 70 to 270 msec. A stimulus appeared in either the visual or the auditory modality. Stimuli in the attended modality were rated as longer than stimuli in the unattended modality. Experiment 3 replicated this finding using a different psychophysical procedure. Experiments 4-6 showed that the finding applies not only to stimuli from different sensory modalities but also to stimuli appearing at different locations within the visual field. The results of all six experiments support the assumption that directed attention prolongs the perceived duration of a stimulus.     

Scoring and interpreting the MMPI with a desk-top calculator

The development of a hospital-based routine system for off-line scoring and interpreting the MMPI with a small desk-top computer (HP 9830) is described. Main features of the system include the use of optical mark reader (OMR) cards instead of ordinary answer sheets and a software monitoring system allowing operator-independent processing. In terms of flexibility, speed, and economy, the system compares favorably with other computer-based test systems.     

Faculty genealogies in five Canadian Universities: Historic-graphical and pedagogical concerns

For those who are both scholars and teachers of the history of psychology, a dilemma arises concerning the historiographic versus pedagogic value of institutional genealogies. As part of the undergraduate History of Psychology course, faculty genealogies were constructed at five Canadian psychology departments (Calgary, Guelph, Toronto, Western Ontario and York); an operational definition of “Ph.D. supervisor” represented mentor-student “institutional” linkages. Seventy-five per cent of the 212 faculty were traceable to nine pioneer figures such as Wilhelm Wundt or William James. In contrasting historiographic pitfalls with pedagogic merits, we suggest that integrating a reflexive and critical examination of histriographic problems may tip the scales in favour of pedagogic reasons for conducting such genealogical research.