Effects of image background on spatial-frequency thresholds for face recognition

A great deal of work has been devoted to the question of which spatial frequencies, if any, are optimal for various visual tasks, such as face and object recognition. However, to date these studies have all been carried out with stimuli set against a uniform background. It is possible that this type of stimulus does not produce ecologically valid results. The natural world in which visual tasks normally take place involves a great deal of luminance variation and distracting visual structure, which may alter the spatial frequencies necessary for a task. We conducted two experiments that examined the effects of image background on the spatial-frequency thresholds (50% maximum of a low-pass or high-pass Butterworth filter) for face recognition by the psychophysical methods of adjustment and constant stimuli. In both experiments we found no significant difference in spatial-frequency thresholds between uniform-grey backgrounds and natural-scene backgrounds, and only minor differences between uniform-grey backgrounds and fractal noise backgrounds. This suggests that results obtained with uniform backgrounds are ecologically valid and that background effects, if they exist, are small.     

The Question of Higher Education for the Blind

Building on the theory of reasoned action (I. Ajzen & M. Fishbein, 1973, 1980; M. Fishbein & I. Ajzen, 1975) and expectancy theory, the authors examined the mediating role of alcohol expectancies in adolescent drinking behaviors by testing whether alcohol expectancy outcomes and valuations (the extent to which these outcomes are perceived as good or bad) mediate the association between peer influences and lifetime alcohol use. Early adolescents (N = 904) from 2 public middle schools in western Michigan completed a battery of questionnaires. Overall, results showed that alcohol expectancies and valuations partially mediated the relations between peer influences (peer use and peer approval) and lifetime alcohol use. The findings suggest that associating with peers who are perceived as using alcohol and approving of drinking may influence adolescents’ alcohol expectancies. The authors briefly discuss future research directions and implications for prevention.     

True Love Waits: Do Southern Baptists? Premarital Sexual Behavior Among Newly Married Southern Baptist Sunday School Students

This study measures premarital sex prevalence, sources of sex education, and support for secular sex education among 151 newly married young adults surveyed at 9 Texas Southern Baptist churches. More than 70% of respondents reported having had premarital vaginal or oral sex, but more than 80% regretted premarital sex. The proportion of premarital sex exceeded 80% in 6 of 9 churches, among men and women married after age 25 and women married before age 21. School sex education was the only source of information about sexually transmitted infections for 57% of respondents, and 65% supported secular sex education despite church opposition.     

Causation,randomness, and pseudo-randomness in John Venn's logic of chance

In 1866, the young John Venn published The Logic of Chance, motivated largely by the desire to correct what he saw as deep fallacies in the reasoning of historical determinists such as Henry Buckle and in the optimistic heralding of a true social science by Adolphe Quetelet. Venn accepted the inevitable determinism implied by the physical sciences, but denied that the stable social statistics cited by Buckle and Quetelet implied a similar determinism in human actions. Venn maintained that probability statements were intelligible solely as projections of the ultimate frequency of an outcome in an unlimited series of trials and therefore led to no inferences about free will. An issue here was Venn's claim that although the aggregate probability may be stable, the individual events were completely irregular and, in fact, displayed randomness. Venn's concept of randomness was really apparent, or pseudo-, randomness, which could be totally determined. Ironically, Venn's frequentist position was very useful to the growing field of statistics, which could develop correlations and predictive models empirically without having to address implications for personal freedom or fatalism.     

Wisconsin card sorting test and Halstead Category Test performances of children and adolescents who exhibit the syndrome of nonverbal learning disabilities

Abstract

Wisconsin Card Sorting Test (WCST) and Halstead Category Test (HCT) performances of 15 children/adolescents (age range 9 to 17 years) diagnosed with the syndrome of nonverbal learning disabilities (NLD) and 15 age-, gender-, and FSIQ-matched verbal learning-disabled (VLD) controls were examined. The VLD group made significantly fewer errors on the HCT than did the NLD group. In addition, the VLD controls significantly outperformed the NLD participants on seven of the nine WCST index scores (all except failure to maintain set and learning to learn scores). Consistent with the adult literature, the common variance between the HCT and WCST was modest, indicating that these two neuropsychological measures gauge different domains of functioning. It is suggested that the HCT assesses conceptualization/higher order reasoning abilities, whereas the WCST taps dimensions of executive functioning.     

Classification Rules for Basic Phonological Processing Disabilities and Nonverbal Learning Disabilities: Formulation and External Validity*

Rules for the classification of two subtypes of learning disabilities (LD), namely, Basic Phonological Processing Disabilities (BPPD) and Nonverbal Learning Disabilities (NLD), are reported. These rules (refined as a result of application to two separate samples of children with LD) were used to select children from an entirely new sample who could be classified as having ‘definite’ or ‘probable’ BPPD or NLD. As a first step in the external validation of these rules, the patterns of psychosocial functioning exhibited by these two subtypes of LD were determined. As predicted, the vast majority of the BPPD subtype exhibited a pattern most consistent with normal or relatively normal psychosocial adjustment, and no appreciable increase in the incidence of significant psychosocial disturbance with advancing years. Also, as predicted, an increasing incidence of internalized psychosocial dysfunction (a form of significant psychosocial disturbance) was evident in the NLD subtype with advancing years. It is clear that children classified as having BPPD or NLD using these rules exhibit quite different, and predicted, relative patterns of psychosocial functioning. Thus, in this sense, the rules have concurrent validity. Finally, sets of rules/criteria for classification are presented that reflect their actual incidence in the two subtypes of LD generated for use in the validation phase of this investigation. These rules would appear to be useful for clinical purposes. It is also clear that they should be subjected to further validation studies in a broader age range for clinical and research purposes.     

Being in the Game: Effects of Avatar Choice and Point of View on Psychophysiological Responses During Play

The innovative features of multi-player computer games offer compelling opportunities for self-representation during interactions, and the ways in which these avatars are chosen and manipulated may change interactive experiences. This study investigated the effects of avatar choice (choice vs. no choice) and visual point of view (POV; first-person vs. third-person) on the physiological arousal and subjective evaluations of game experiences. A 2 (Avatar Choice, No Avatar Choice) × 2 (first-person POV, third-person POV) × 2 (female players, male players) mixed-design experiment was conducted (N = 22). The results demonstrated that being able to pick the character that will represent the player in the game leads to greater arousal, especially for males. Visual POVs alone did not affect the game player's arousal, but moderated the effect of avatar choice on the game player's heart rates. Avatar choice produced a more pronounced effect in the third-person POV (where the “camera” was located behind the avatar) in which avatar choice was visually more reinforced than in the first-person POV (where the “camera” was the eyes of the avatar). The results also revealed that the gender of the game player was a significant factor in game play experience. The results suggest theoretical implications of video game self-representation and effects on game player's psychophysiological responses.     

ENHANCING THE ACCURACY OF LOW‐FREQUENCY BEHAVIOR DATA COLLECTION BY DIRECT‐CARE STAFF

Accurate data collection on low‐frequency problem behavior is imperative given the paucity of opportunities to observe, record, and assess responding. Infrequently occurring behavior also provides a challenge for staff training relative to data collection. The present study evaluated the use of task clarification and feedback to teach direct‐care staff members to take data on recorded, simulated problem behavior. Results indicated that the procedures were effective in increasing accuracy not only in the contrived scenarios but also for problem behavior in the natural environment. These data suggest that task clarification and feedback on simulated problem behavior may be an effective method to increase accurate data collection on problem behavior in the natural environment. Copyright © 2013 John Wiley & Sons, Ltd.     

Relationships of children's grade in school,sex, and social class to teachers' ratings on the behavior problem checklist

The present study investigated the relationships of children's grade in school, sex, and social class to teachers' ratings on the Behavior Problem Checklist (BPCL). The sample consisted of 1,999 white children from kindergarten through fifth grade who were in regular classes. Three conclusions may be drawn from the study. The first is that grade and the interactions of grade with sex and social class are determinants of scores on the BPCL, but that no particular trends are characteristic of the relationships between these and the dependent variables. The second is that sex and social class are also determinants of scores on the BPCL, with boys and children from the lower social classes having more problems and girls and children from the higher social classes having fewer problems. The third is that the differences between schools and between teachers are responsible for more of the variance on the BPCL than grade, sex, and social class.For permission and assistance in obtaining the sample, the authors gratefully acknowledge John Bowser, superintendent of the Alief Independent School District, Alief, Texas. The authors thank Dorothy Schreiner, secretary-to-the-superintendent, and the following school principals and their teachers for their valuable cooperation: Betty A. Bennett, Jane E. Hunt, Bertha Jamison, James Keel, and James R. Woodfin. Appreciation is also expressed to Richard M. Patterson and James J. Wilmoth who generously offered their advice concerning the data analysis.