The role of part structure in the perceptual localization of a shape

The process of object localization may be accomplished with respect to a particular reference location, such as the center of gravity, COG (eg Vishwanath and Kowler, 2003 Vision Research 43 1637-1653). Here, we investigated how part structure affects an object's reference location. The reference location was evaluated with a measure of the illusory displacement of an internal target element embedded within a larger object (Morgan et al, 1990 Vision Research 30 1793-1810). To examine whether the reference location is different for shapes with part structure, two shapes were tested: circle (small and large; no part structure) and bell (shape with two parts, one larger than the other). Results were examined with respect to two predictions: either the location of an object is based on its shape as a whole, disregarding part structure (ie a single, overall COG), or the parts are processed separately (different COGs). With the circles, the results showed a systematic illusory displacement of the internal target toward the COG. With the bell, the illusion was significantly weaker than with both circles--even though the main part of the bell had the same size as the small circle, and its horizontal axis had the same extent as the large circle. Moreover, the distance judgments for the bell were consistent with a (weaker) reference point being located at the COG of the larger part, rather than at the COG of the entire bell. These results show that the part structure of a shape plays a role in the representation of its location, and that for complex shapes the perceived location of an embedded element depends more on the parts within which it is embedded, rather than on the whole shape.     

Evaluating the relative effects of feedback and contingent money for staff training of stimulus preference assessments

Performance feedback has facilitated the acquisition and maintenance of a wide range of behaviors (e.g., health-care routines, seat-belt use). Most researchers have attributed the effectiveness of performance feedback to (a) its discriminative functions, (b) its reinforcing functions, or (c) the combination of the two. In this study, we attempted to evaluate the relative contributions of the discriminative and reinforcing functions of performance feedback by comparing a condition in which the discriminative functions were maximized and the reinforcing functions were minimized (i.e., performance-specific instructions without contingent money) with one in which the reinforcing functions were maximized and the discriminative functions were minimized (i.e., contingent money with no performance-specific instructions). We compared the effects of these two conditions on the acquisition of skills involved in conducting two commonly used preference assessments. Results showed that acquisition of these skills occurred primarily in the condition with performance-specific instruction without contingent money, suggesting that the delivery of performance-specific instructions was critical to skill acquisition, whereas the delivery of contingent money had little effect.     

Cognitive therapy for post-traumatic stress disorder: development and evaluation

The paper describes the development of a cognitive therapy (CT) program for post-traumatic stress disorder (PTSD) that is based on a recent cognitive model (Behav. Res. Therapy 38 (2000) 319). In a consecutive case series, 20 PTSD patients treated with CT showed highly significant improvement in symptoms of PTSD, depression and anxiety. A subsequent randomized controlled trial compared CT (N = 14) and a 3-month waitlist condition (WL, N = 14). CT led to large reductions in PTSD symptoms, disability, depression and anxiety, whereas the waitlist group did not improve. In both studies, treatment gains were well maintained at 6-month follow-up. CT was highly acceptable, with an overall dropout rate of only 3%. The intent-to-treat effect sizes for the degree of change in PTSD symptoms from pre to post-treatment were 2.70-2.82 (self-report), and 2.07 (assessor-rated). The controlled effect sizes for CT versus WL post-treatment scores were 2.25 (self-report) and 2.18 (assessor-rated). As predicted by the cognitive model, good treatment outcome was related to greater changes in dysfunctional post-traumatic cognitions. Patient characteristics such as comorbidity, type of trauma, history of previous trauma, or time since the traumatic event did not predict treatment response, however, low educational attainment and low socioeconomic status were related to better outcome.     

Motivational interviewing for employment: An exploration of practitioner skill and client change talk

Motivational interviewing (MI) is an evidenced-based approach for building and strengthening motivation for change. The effect of MI training on practitioner conversations with unemployed clients within a government work and income service was evaluated using a mixed-method approach, comprising a multiple-baseline across practitioner (n = 5) design and a pre/post quasi-experimental design. After workshop MI training, practitioners demonstrated greater MI skills in conversations with clients, and MI skills were maintained during the period of post-workshop feedback and coaching. There was also more change talk spoken by clients in conversations that occurred post-MI workshop training compared to pre-training, suggesting increased motivation for change.     

The Corsi Block-Tapping Task: Methodological and Theoretical Considerations

The Corsi block-tapping task has enjoyed extensive use in clinical and experimental studies for a quarter of a century and is arguably the single most important nonverbal task in neuropsychological research. Nevertheless, there has been considerable inconsistency not only in the administration and scoring of this measure, but also in the physical properties of the test apparatus. In this paper, we survey a wide range of studies that have made use of the block-tapping task during the past 25 years and provide a detailed appraisal of the manifold methodological variations. Additionally, we discuss the historical context in which the Corsi originated and offer a critical examination of the cognitive processing operations purported to underlie performance on this task.     

A COMPARISON OF NONCONTINGENT REINFORCEMENT AND SENSORY EXTINCTION AS TREATMENTS FOR SELF-INJURIOUS BEHAVIOR

We compared the effects of two treatments, noncontingent reinforcement (NCR) and sensory extinction (EXT), on the self-injurious behavior (SIB) exhibited by 3 individuals with developmental disabilities. Results of a functional analysis indicated that their SIB was not maintained by social reinforcement, as indicated by undifferentiated responding across assessment conditions or higher rates of responding in the alone condition. Prior to treatment, leisure probes were conducted to identify highly preferred items for use in the NCR condition, and equipment probes were conducted to identify devices that produced the greatest behavioral suppression for use in the EXT condition. Following baseline, treatment was implemented in a multiple baseline across subjects design, and the effects of NCR and EXT were compared in a multielement format. During NCR sessions, participants had continuous access to a highly preferred item. During EXT sessions, participants wore equipment (gloves or protective sleeves) that seemed to attenuate stimulation directly produced by their SIB, while still allowing the behavior to occur. Results indicated that both procedures were effective in reducing SIB, although NCR was associated with either more rapid or greater overall response suppression.     

EQUATING INVERSE PROBABILITIES IN IMPLICIT PERSONALITY JUDGMENTS

Abstract— Meehl and Rosen (1955) observed that their colleagues tended to equate the sensitivity of a sign (its probability given a diagnostic category) with its predictive accuracy (the probability of the diagnostic category given the sign). Such equating of inverse probabilities implies ignoring base rates. Later, many researchers demonstrated such neglect in a number of experimental contexts involving hypothetical judgments; others have found some use of base rates—but only when base rates were supplied by the experimenter, in which case even irrelevant base rates influenced judgment. The present study tested for equating conditional probabilities in a context similar to the contexts involved in the initial observations—that is, subjects strove for accuracy rather than attempted to make good judgments about hypothetical problems, and the base rates were generated by the subjects themselves. Neglect of base rates was revealed by within-individual comparisons showing subjects equated inverse probabilities without equating the corresponding unconditional ones.     

Behavioural knowledge amongst staffing groups for the care of the intellectually disabled

A multiple choice inventory was used to assess the behavioural knowledge of staff providing services to people with an intellectual disability. The relationships between performance on the inventory and other staff related variables were investigated. Results support previous research and indicate a low level of behavioural knowledge amongst direct care staff. The implications of these results are discussed in relation to staff training and selection.     

Exhausting or exhilarating? Conflict as threat to interests,relationships and identities

Some conflicts are experienced as depleting and exhausting whereas others are experienced as stimulating and invigorating. We explored the possibility that the focus of perceived threat in conflict determines whether it produces taxing stress or vitalizing arousal. Studies 1 and 2 established that attending to threats to interests, relationships, and identities during interpersonal conflict differentially relates to motivational goals, empathy and perspective-taking, femininity, and a collectivistic self-construal. Study 2 also found that perceived threats to relationships are associated with lower challenge appraisals and energy mobilization. Studies 3 and 4 experimentally manipulated threats to different targets and demonstrated causal effects of threat perceptions on self-reported energy mobilization and the consumption of comfort foods. Taken together, these studies demonstrate that conflicts which threaten relationships are experienced as significantly more depleting than conflicts that threaten either tangible interests or elements of individuals' identities, and explain when, why and for whom conflict is exhausting.