Depth separation and the Ponzo illusion

The Ponzo illusion refers to an apparent change in length of objectively equal parallel lines induced by enclosure within an acute angle. The present study investigated this illusory change in stimulus extent as a function of the relative depth positions of the parallel lines and the inducing angle. To permit facile and unconfounded manipulation of apparent depth, the stimuli comprising the Ponzo configuration were stereoscopic contours formed from dynamic random-element stereograms. The main results were: (1) apparent depth separation exerted a strong influence on illusion magnitude; (2) this influence was asymmetrical in that illusion magnitude decreased when the inducing angle appeared in depth behind the parallel lines and increased when the inducing angle appeared in depth in front of the lines. These data are consistent with a general theory of space perception that assumes that information about depth position is processed prior to information about stimulus characteristics.     

Disentangling Type A behavior: The roles of ambition,insensitivity, and anxiety

This study identified stable components of Type A behavior as usually defined, and examined their relationships with more traditional psychological constructs. Overall scores on the most popular Type A measure (a version of the Jenkins Activity Survey) were moderately associated with ambition but largely unrelated to measures of adjustment. An item analysis yielded subcomponents of Drivenness and Involvement. Drivenness was unrelated to ambition, but was positively related to anxiety and negatively related to interpersonal perceptiveness. Involvement was positively related to ambition and to interpersonal competence. It is suggested that the Jenkins Activity Survey measures a heterogeneous mixture of constructive commitment and self-defeating responses that clouds its psychological interpretation.     

Human figure drawings of gender-problem children: A comparison to sibling,psychiatric, and normal controls

The Draw-a-Person test was used to evaluate a number of questions regarding children referred for potential problems in their gender-identity development (N = 36). Sibling (N = 31), psychiatric (N = 23), and normal (N = 30) children served as comparison groups. The major results included the following: (1) The gender-referred children were more likely to draw an opposite-sex person when requested to "draw a person" than were the other three groups; (2) the gender-referred children who drew an opposite-sex person were more likely to play with opposite-sex toys and dress-up apparel on a free-play task than were the gender-referred children who drew a same-sex person; (3) the gender-referred children drew taller opposite-sex persons than same-sex persons; (4) using Koppitz's (1968) criteria, the normal children had a smaller proportion of emotional disturbance indicators in their same-sex drawings than did the other three groups. These findings were discussed with regard to psychometric and interpretive issues in the assessment of children with atypical gender-role behavior.     

Introversion-extraversion: the Bell-Magendie law revisited

Evidence from several sources, including psychophysical, electrodermal and evoked potential measures, indicates that introverts display an enhanced response to sensory stimulation. There is also evidence, primarily from psychophysical studies, which suggests that extraverts may be disposed to emit short, strong bursts of motor activity which facilitate performance on tasks that involve gross motor activity but which impede performance on tasks which require refined motor control. The present paper develops an argument in which the differences between introverts and extraverts in the response to sensory stimulation and in the expression of motor activity may be referred to differences at the level of the sensory and motor nerve.     

Working through a group's fantasy of the deceased leader's wish for the group's continuation

This paper reflects the working through of a group's fantasy that the deceased group leader wished the group to continue. As in any defense, the fantasy protected members from the pain of the finality of the leader's death. This article reveals the subjective experience concerning the effect of the leader's death on the group and members' intrapsychic struggle to separate and individuate from the deceased leader, while attending to and striving toward the group's continuation. The group's painful and growing individuation enabled the group to follow its own tasks without the spector of the deceased leader.     

CAPS: A language for modeling highly skilled knowledge-intensive behavior

CAPS is a computer language specialized for modeling highly skilled and knowledge-intensive human activities such as reading (Thibadeau, Just, & Carpenter, 1982). The present paper provides a critical analysis of the particular style of psychological modeling of which CAPS is an example. Suggestions are presented for modeling environments for psychologists.     

An electronic cine camera system for the automatic collection and analysis of high-speed movement of unrestrained animals

A system is decribed that collects visual data using a solid-state photodiode image sensor at rates of up to 600 frames/sec in a binary format suitable for image-analysis techniques. Of particular interest is the system’s ability to analyze high-speed movement of animals without prior modification of the subject (e.g., attachment of lamps or reflectors to the subject).     

The semantic congruity effect: Some tests of the expectancy hypothesis

Subjects comparing items in memory along some dimension are usually quicker to specify the lesser (than the greater) of two low magnitude items and the greater (than the lesser) of two high magnitude ones. One account explains this congruity effect as due to subjects instructed to specify the higher as expecting high magnitude items to follow and the reverse being true for subjects specifying the lesser. Three experiments tested this expectancy hypothesis. In experiment 1, subjects were set to the actual size range of each pair before the pair was shown but the congruity effect still occurred. In experiments 2 and 3, subjects compared critical pairs from a narrow size range plus more from either the same or much broader ranges. Times to compare the critical pairs were the same regardless of the range of the other pairs that subjects were exposed to. These results are strong evidence against the expectancy hypothesis.