Apparent misalignment of oblique coplanar bars in depth

Following preliminary observations of apparent misalignment of coplanar surfaces in a three-dimensional (3-D) form of the Poggendorff Figure viewed in depth, the effect was investigated in five experiments and compared with the 2-D Poggendorff effect in the same object in a sixth. The effect in depth occurred with the complete object when it was viewed binocularly but did not do so with the oblique bars alone or when the object was viewed monocularly. The effect did not vary with oblique-parallel angles of 30°, 45°, and 60° and was absent when the angle was 90°. It varied as a function of the distance between the parallels, but was unaffected by a regular pattern on the oblique bars. A smaller 2-D Poggendorff effect occurred when the upper edges of the object were viewed from above. Although the depth effect was robust, its variance was high compared with that of the 2-D effect, indicating that acuity for misalignments of oblique elements in depth is poor. An explanation of apparent misalignment of oblique elements in 2-D and 3-D space in terms of a perceptual compromise between alignment in an oblique axis and separation relative to the axes of the parallels is proposed.     

Gravity constraints in infant motor development

The effect of gravity in determining if and when during infancy movements eventuate and the rate at which they develop is unknown. In accordance with intersegmental relationships (Hof, 1992), a muscle moment during infancy would have to develop more rapidly than the gravitational moment before movement could occur. In this investigation, the effect of growth through the influence of gravity on the joint moments in the axial region when infants were in a prone or supine posture was examined. A mathematical model that considers the body to be composed of transverse elliptical cylinders, 1 cm deep and of known density, was used in estimating the mass of the 16 segments of the body. The gravitational moments about 3 joints within the axial region (C7-T1, T12-L1, and the hip) were determined by summation, using the radii from the joint transverse axis to the center of mass of the segments. Infants (N = 27) aged between 9 and 36 weeks at the beginning of the study were tested monthly 6 times, and the effect of growth on the gravitational moments was represented by first-order polynomials. Age x Joint analysis of variance (ANOVA) of the mean slopes of the regressions for the gravitational moments revealed significant main effects for age and joint. The means increased monotonically with the number of segments and decreased as infants aged. The mean slopes of the neck and trunk joints were significantly smaller than that of the hip joint. With increasing age, the gravitational slope was significantly smaller. The changes in the gravitational moments during infancy are seen as likely control parameters effecting phase shifts in motor patterns during development.     

Reproduction memory of two-event sequences in pigeons

Six pigeons were trained to reproduce two-event sequences in an experiment that employed a discrete-trial procedure that required subjects to peck one of four possible sample sequences (left-left, left-right, right-right, right-left) signaled on a given trial by the successive illumination of response keys. Following a retention interval (0.1 to 30 seconds), a reinforcer was delivered if a subject reproduced the prior sample sequence during a test condition in which both left and right keys were illuminated. The pigeons readily reproduced the orders in which they had just seen and pecked two illuminated keys. Reproduction accuracy declined as the retention interval was increased. Homogeneous sequences (left-left, right-right) were reproduced with greater accuracy than heterogeneous sequences.     

Self-reports of depression and state-trait anxiety: evidence for differential assessment.

Several researchers have found anxiety and depression to be indistinguishable in nonclinical samples and have suggested that both constructs may be components of a general psychological distress process. Another possibility is that overlap is due to the psychometric limitations of scales used. A series of exploratory factor analyses were conducted in a nonclinical sample (N = 605) using the Beck Depression Inventory (BDI; Beck, 1978), the State-Trait Anxiety Inventory (STAI; Spielberger, 1983), and the Endler Multidimensional Anxiety Scales (EMAS; Endler, Edwards, & Vitelli, 1991). Both state and trait anxiety and depression could be differentiated with the BDI and the EMAS but not with the STAI. Some theoretical models of negative affectivity or general psychopathology may be premature.     

Book reviews

The Psychological Record -     

Three-space inference from two-space stimulation.

Oblique contours sloping at 30 degrees with respect to the horizontal were presented alone, in combination to form chevrons, or with a vertical line to form arrowhead or Y patterns; they were projected onto a screen in the frontal parallel plane and viewed from positions that gave viewing angles of 90 degrees (normal to the screen's surface), 53 degrees, or 34 degrees. The perceived orientation of the contours, as assessed by a movable arm that the subjects set to be parallel to the obliques, changed monotonically as a function of viewing angle. The change was as great for single obliques as for combinations of obliques within the chevron, arrowhead, and Y patterns. The results of Experiment 1 were extended in Experiment 2, in which obliques at 30 degrees and 50 degrees with respect to the horizontal were presented singly or in combination as chevron patterns. It is argued that the results of both experiments indicate that single two-space oblique lines are immediately interpreted as lying in three-space and that the changes in perceived orientation are a consequence of this perceptual inference.     

Success strivings and their relationship to affective work behaviors: gender differences.

Gender differences in the importance of six life success dimensions and their relationships to job satisfaction, job involvement, and propensity to stay on the job were examined among 756 working women and men in southeast Florida. Results showed that the female participants rated family relationships, personal fulfillment, and security as more important success measures than their male counterparts did, and they rated status/wealth as less important. Professional fulfillment and security were not significantly different. The relationships between measures of success and work behaviors also varied significantly by gender, even after controlling for demographic and job position variables.     

A meta-analysis of the reliability and validity of the Rorschach

The results of a meta-analysis of Rorschach studies indicate that reliabilities in the order of .83 and higher and validity coefficients of .45 or .50 and higher can be expected for the Rorschach--when hypotheses supported by empirical or theoretical rationales are tested using reasonably powerful statistics. Three important determinants of variance accounted for in a variety of Rorschach scores were identified in 530 statistics from 39 papers published in the Journal of Personality Assessment from 1971 to 1980. The a priori theoretical or empirical evidence determining the likelihood of obtaining significant results, and the power of the statistic used to measure the results, as well as the interaction between the likelihood of results and the power of the statistic used, were all significant determinants of the proportion of variance accounted for in the Rorschach measures reported.     

Psychopathology and substance-related problems during early adolescence: a survival analysis.

Examined the chronological and statistical relations among onsets of psychopathology, alcohol and cannabis use, and substance-related problem psychopathology, alcohol and cannabis use, and substance-related problems from late childhood through early adolescence in boys of fathers with substance use disorder (SUD; high average risk: n = 177) and without SUD (low average risk: n = 203) using survival analysis. Proportional hazard models indicated that antisocial disorders were predicted by risk group and mediated the observed relation between risk group and substance-related problems. Negative affect disorders were predicted by risk group but did not predict substance involvement in early adolescence. Results support a model in which paternal SUD predisposes to increased antisocial and negative affect disorders in boys, and antisocial disorders lead to substance-related problems in early adolescence.