Expertise and the perception of kinematic and situational probability information

Two experiments were conducted on the nature of expert perception in the sport of squash. In the first experiment, ten expert and fifteen novice players attempted to predict the direction and force of squash strokes from either a film display (occluded at variable time periods before and after the opposing player had struck the ball) or a matched point-light display (containing only the basic kinematic features of the opponent's movement pattern). Experts out-performed the novices under both display conditions, and the same basic time windows that characterised expert and novice pick-up of information in the film task also persisted in the point-light task. This suggests that the experts' perceptual advantage is directly related to their superior pick-up of essential kinematic information. In the second experiment, the vision of six expert and six less skilled players was occluded by remotely triggered liquid-crystal spectacles at quasi-random intervals during simulated match play. Players were required to complete their current stroke even when the display was occluded and their prediction performance was assessed with respect to whether they moved to the correct half of the court to match the direction and depth of the opponent's stroke. Consistent with experiment 1, experts were found to be superior in their advance pick-up of both directional and depth information when the display was occluded during the opponent's hitting action. However, experts also remained better than chance, and clearly superior to less skilled players, in their prediction performance under conditions where occlusion occurred before any significant pre-contact preparatory movement by the opposing player was visible. This additional source of expert superiority is attributable to their superior attunement to the information contained in the situational probabilities and sequential dependences within their opponent's pattern of play.     

Abortion, Intimacy, and the Duty to Gestate

In this article, I urge that mainstream discussions of abortion are dissatisfying in large part because they proceed in polite abstraction from the distinctive circumstances and meanings of gestation. Such discussions, in fact, apply to abortion conceptual tools that were designed on the premiss that people are physically demarcated, even as gestation is marked by a thorough-going intertwinement. We cannot fully appreciate what is normatively at stake with legally forcing continued gestation, or again how to discuss moral responsibilities to continue gestating, until we appreciate in their own terms the goods and evils distinctive of gestational connection. To underscore the need to explore further the meanings of gestation, I provide two examples of the difference it might make to legal and moral discussions of abortion if we appreciate more fully that gestation is an intimacy.     

Stimulus-determined discrimination mechanisms for color search

Visual attention can be goal driven, stimulus driven, or a combination of the two. Here we report evidence for an unexpectedly stimulus-driven component of visual search for a target defined by color. Observers demonstrated a surprisingly cost-free ability to incorporate multiple classifiers in search for a target of one color from among distractors of other colors. A target color was presented among distractors that could change from trial to trial (intermixed presentation) or that remained constant across all trials in a block (blocked presentation). For blocked presentation, a single search classifier (a mechanism that segregates the target from distractors in color space) could be adopted, whereas for intermixed presentation different classifiers had to be used when the distractor colors changed. The benefit of blocked presentation was very small, suggesting that the appropriate classifier was determined very quickly in trials for which the classifier changed. The results suggest that the stimulus-driven activation of an appropriate stimulus classifier can be very efficient.     

Assessment and Diagnosis of DSM-IV Anxiety Disorders

Anxiety disorders, the 2nd most common type of mental disorders, are among the most frequently missed or misdiagnosed disorders (Frances & Ross, 1996). Once they are diagnosed, effective treatments exist for them. This article provides a review of current knowledge on the assessment and diagnosis of anxiety disorders classified in the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (American Psychiatric Association, 1994). Emphasis is on the recognition of anxiety as a dominant symptom, frameworks for determining specific anxiety disorders, and patterns of comorbidity.     

The Microanalysis of Memory Span and Its Development in Childhood

It is not clear from the literature why, as children develop, there are important increases in memory span, the number of just-presented items that the participant can repeat in the correct serial order. To understand this, some recent results on capacity limits and processing rates were re-analyzed. We first describe results using a conventional measure of performance in immediate memory tasks that is affected by the list length (proportion correct). Next we describe results using a less conventional measure (number correct) that is unaffected by list length under circumstances in which attention to the list during its presentation is curtailed. This measure can estimate an individual's limited-capacity storage ability. Last, we examine measures of spoken response timing that do and do not change with list length. We show that unconventional measures that do not change with list length, but do change with development, are especially useful in assessing basic changes in information processing parameters, including increases in memory capacity and processing speed.     

Time course of word identification and semantic integration in spoken language

The minimum duration signal necessary to identify a set of spoken words was established by the gating technique; most words could be identified before their acoustic offset. Gated words were used as congruous and incongruous sentence completions, and isolation points established in the gating experiment were compared with the time course of semantic integration evident in event-related brain potentials. Differential N400 responses to contextually appropriate and inappropriate words were observed about 200 ms before the isolation point. Semantic processing was evident before the acoustic signal was sufficient to identify the words uniquely. Results indicate that semantic integration can begin to operate with only partial, incomplete information about word identity. Influences of semantic constraint, word frequency, and rate of presentation are described.     

The tasks of self-managing hepatitis C: the significance of disclosure

The narratives of those with hepatitis C were viewed through the lens of Corbin and Strauss' [Corbin, J., & Strauss, A. (1988). Unending work and care: Managing chronic illness at home. The Jossey-Bass health series and The Jossey-Bass social and behavioral science series. San Francisco, CA: Jossey-Bass.] self-management model for chronic illness, using qualitative methodology. Fifteen Australian hepatitis C positive interviewees described the challenges and turning points in adjusting to their diagnosis. The data were analysed using open- and closed-coding methods. Support was found for a self-management model encompassing medical, emotional and life role facets for those adjusting to life with hepatitis C. Unique challenges emerged beyond those described by Corbin and Strauss (1988), namely that disclosure impacted both positively and negatively on the tasks of self-management. It was concluded that self-management may be compromised by disclosure, particularly distress derived from hepatitis C-related stigma. The self-management tasks described contribute to broadening clinicians' understanding of the challenges faced by those living with hepatitis C.