MUST FIGURE-GROUND ORGANIZATION PRECEDE OBJECT RECOGNITION?

The assumption that figure-ground segmentation must precede object or shape recognition has been central to theories of visual perception We showed that assumption to be incorrect in an experiment in which observers reported the first perceived figure–ground organization of briefly exposed stimuli depicting two regions sharing a figure–ground border We manipulated the symmetry of the two regions and their orientation-dependent denotivity (roughly, their meaningfulness), and measured how each of these variables influenced figure–ground reports when the stimuli were exposed for 14, 28, 57, 86, or 100 ms, and followed immediately by a mask Influences on figure–ground organization from both symmetry and orientation-dependent object recognition processes were found, both were observed first in the 28-ms condition Object recognition inputs did not dominate symmetry inputs We suggest that object recognition processes may operate simultaneously on both sides of edges detected before figure–ground relationships are determined     

The role of three-dimensional depth cues in infants' perception of partly occluded objects

Newborn infants were familiarized to a three dimensional display consisting of a rod which moved behind a central occluder, so that only the top and bottom of the rod were visible. The infants' eyes were 38 cm from the rod and the occluder was 15 cm in front of the rod, a separation intended to ensure that the gap between the two was detected by the infants. On subsequent test trials the infants looked longer at a complete rod than at two rod pieces, suggesting that the hidden unity, or completeness of the rod had not been perceived. In a study by Johnson and Náñez (in press), using computer. generated stimuli, 4 month olds perceived the hidden unity of a similar display presented on a VDU in the complete absence of three. dimensional depth cues. Taken together, these findings suggest that, for these displays, perception of three. dimensional depth cues is not necessary for the detection of the unity of partially hidden objects. It is suggested that age changes in early infancy in the perception of occluded objects may result either from the emergence of abilities to perceive objects from kinematic information or from the emergence of sensitivity to that information itself.     

Psychometric properties of the Wolpe-Lazarus assertiveness scale

The psychometric properties of the Wolpe-Lazarus Assertiveness Scale (WLAS) were evaluated with a sample of 100 male and 157 female psychiatric patients. There were no significant differences with regard to males and females for total WLAS scores. The WLAS seems to be internally consistent and has acceptable split-half and test-retest reliabilities. A factor analysis performed separately for males and females indicates that the 10 most prominent factors account for about 60% of the accumulated variance. The primary factor, shared by males and females, was labeled General Expressiveness. There was little evidence for the external validity of the WLAS when total scores were correlated with performance on a role play test. However, when WLAS factor scores were evaluated in light of role played performance, somewhat better evidence of the external validity of the WLAS was found in two of the factors for the females.     

Nonverbal Mediators of Expectancy Effects in Black and White Children1

Seventy-two white undergraduates of both sexes taught a lesson “What is psychology?” to a 10-year-old male confederate. Four confederates, two white and two black, alternated in the three conditions of induced expectancy: Subjects were told the child was bright, dull, or were given no information. Unknown to subjects, their nonverbal behavior during the lesson was videotape recorded. Results indicated that induced expectancy affected subject nonverbal behavior only when the confederate was white. Subjects smiled more, looked more, and nodded more at the white “bright” confederates than the white control or “dull” confederates. However, expectancy had no effect, positive or negative, when the confederate was black. In addition, white confederates received more positive nonverbal behavior overall than did black confederates.     

Neuropsychological significance of variations in patterns of academic performance: Verbal and visual-spatial abilities

Forty-five 9- to 14-year-old children with learning disabilities whose WISC Full Scale IQs fell within the range of 86–114 were divided into three groups on the basis of their patterns of reading, spelling, and arithmetic achievement. Group 1 was composed of children who were uniformly deficient in reading, spelling, and arithmetic; children in Group 2 were relatively adept at arithmetic as compared to their performance in reading and spelling; Group 3 was composed of children whose reading and spelling performances were average or above, but whose arithmetic performance was relatively deficient. The performances of these children on 16 dependent measures were compared. The performances of Groups 1 and 2 were superior to that of Group 3 on measures of visual-perceptual and visual-spatial abilities; Group 3 performed at a superior level to that of Groups 1 and 2 on measures of verbal and auditory-perceptual abilities. The results are discussed in terms of the relationships between varying patterns of academic abilities and patterns of brain-related behaviors, and the nature of the neuropsychological abilities that may limit performance on arithmetic calculation tasks.The research reported herein was supported, in part, under Grant #195 of the Ontario Mental Health Foundation. Funds were also supplied by Windsor Western Hospital Centre.     

Service Delivery and High School Peer Counseling Systems

Earlier rationales supporting peer counseling systems have emphasized possibilities of increased service delivery and innovative counseling models. An ongoing peer counseling program was studied through questionnaires administered to clients, teachers, the general student body, and peer counselors themselves. Specific attention was directed to numbers of students served. Distinctions between formal and informal counseling relationships and problem content areas are discussed. Results suggested the existence of two distinct service delivery systems. An informal system served large numbers of self-referred students and dealt primarily with personal-social problems. A formal system reached fewer students, relied upon staff referral, and addressed academic difficulties. Implications for the design of peer counselor programs with varying goals were discussed.     

A digital frequency discriminator for biofeedback research

The design and construction of a digital frequency discriminator, useful in various research and clinical applications of biofeedback, is presented. The module may be constructed for approximately $25 (excluding power supply and mounting hardware).