Aging and the perception of 3-D shape from dynamic patterns of binocular disparity

In two experiments, we investigated the ability of younger and older observers to perceive and discriminate 3-D shape from static and dynamic patterns of binocular disparity. In both experiments, the younger observers' discrimination accuracies were 20% higher than those of the older observers. Despite this quantitative difference, in all other respects the older observers performed similarly to the younger observers. Both age groups were similarly affected by changes in the magnitude of binocular disparity, by reductions in binocular correspondence, and by increases in the speed of stereoscopic motion. In addition, observers in both age groups exhibited an advantage in performance for dynamic stereograms when the patterns of binocular disparity contained significant amounts of correspondence "noise." The process of aging does affect stereopsis, but the effects are quantitative rather than qualitative.     

Hearing a face: cross-modal speaker matching using isolated visible speech

An experiment was performed to test whether cross-modal speaker matches could be made using isolated visible speech movement information. Visible speech movements were isolated using a point-light technique. In five conditions, subjects were asked to match a voice to one of two (unimodal) speaking point-light faces on the basis of speaker identity. Two of these conditions were designed to maintain the idiosyncratic speech dynamics of the speakers, whereas three of the conditions deleted or distorted the dynamics in various ways. Some of these conditions also equated video frames across dynamically correct and distorted movements. The results revealed generally better matching performance in the conditions that maintained the correct speech dynamics than in those conditions that did not, despite containing exactly the same video frames. The results suggest that visible speech movements themselves can support cross-modal speaker matching.     

The transition to increased automaticity during finger sequence learning in adult males who stutter

The present study compared the automaticity levels of persons who stutter (PWS) and persons who do not stutter (PNS) on a practiced finger sequencing task under dual task conditions. Automaticity was defined as the amount of attention required for task performance. Twelve PWS and 12 control subjects practiced finger tapping sequences under single and then dual task conditions. Control subjects performed the sequencing task significantly faster and less variably under single versus dual task conditions while PWS' performance was consistently slow and variable (comparable to the dual task performance of control subjects) under both conditions. Control subjects were significantly more accurate on a colour recognition distracter task than PWS under dual task conditions. These results suggested that control subjects transitioned to quick, accurate and increasingly automatic performance on the sequencing task after practice, while PWS did not. Because most stuttering treatment programs for adults include practice and automatization of new motor speech skills, findings of this finger sequencing study and future studies of speech sequence learning may have important implications for how to maximize stuttering treatment effectiveness. Educational objectives: As a result of this activity, the participant will be able to: (1) Define automaticity and explain the importance of dual task paradigms to investigate automaticity; (2) Relate the proposed relationship between motor learning and automaticity as stated by the authors; (3) Summarize the reviewed literature concerning the performance of PWS on dual tasks; and (4) Explain why the ability to transition to automaticity during motor learning may have important clinical implications for stuttering treatment effectiveness.     

The Social Ecological Model and Physical Activity in African American Women

Little is known about the social and contextual correlates (e.g., social norms, environment, social networks, and organizational support) influencing the adoption and maintenance of regular physical activity among minority and underserved populations. The purpose of this review was to apply the social ecological model to better understand physical activity among African American women. A review of the literature pertaining to correlates of physical activity among African American women was conducted and applied to a social ecological perspective. Understanding and addressing social and contextual correlates of physical activity behavior among African American women are necessary to establish comprehensive programs, particularly within community settings. The social ecological model provides a strong theoretical basis to guide physical activity intervention in this population.     

Muscular proprioception contributes to the control of interceptive actions

The authors proposed a model of the control of interceptive action over a ground plane (Chardenon, Montagne, Laurent, & Bootsma, 2004). This model is based on the cancellation of the rate of change of the angle between the current position of the target and the direction of displacement (i.e., the bearing angle). While several sources of visual information specify this angle, the contribution of proprioceptive information has not been directly tested. In this study, the authors used a virtual reality setup to study the role of proprioception when intercepting a moving target. In a series of experiments, the authors manipulated proprioceptive information by using the tendon vibration paradigm. The results revealed that proprioception is crucial not only to locate a moving target with respect to the body but also, and more importantly, to produce online displacement velocity changes to intercept a moving target. These findings emphasize the importance of proprioception in the control of interceptive action and illustrate the relevance of our model to account for the regulations produced by the participants.     

Factor structure of coping: two studies of mothers with high levels of life stress

Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to investigate the factor structure of coping in mothers with high levels of life stress. In Study 1, EFA of the Coping Orientation to Problems Experienced (C. S. Carver, M. F. Scheier, & J. K. Weintraub, 1989) in a sample of mothers of full-term or very low birth weight 2-year-old children yielded 7 reliable coping factors. Each factor accounted for significant variance in at least 1 of 6 outcomes measuring maternal-child well-being. In Study 2, CFA was used to cross-validate the EFA model on the basis of the responses of mothers of 2-year-old children with prenatal polysubstance exposure. CFA results revealed a moderately good fit, confirming the factor structure in a 2nd, independent sample of mothers with high levels of life stress.     

Categorization and cognitive deficits in compulsive hoarding

According to the cognitive-behavioural model of compulsive hoarding, information-processing deficits in the areas of attention, memory, decision-making, and categorization contribute to hoarding behaviour. The purpose of the current study was to examine whether individuals with compulsive hoarding exhibited impairment on executive functioning and categorization tasks. Three groups of participants were recruited (N = 60): individuals with compulsive hoarding syndrome, individuals with an Axis I mood or anxiety disorder, and non-clinical control participants. All participants completed self-report measures of cognitive difficulties, neuropsychological tests of executive functioning and decision-making, and four categorization tasks. Results suggested that hoarding participants reported more cognitive failures and more problems with attention and decision-making than non-clinical control participants. In addition, hoarding participants performed worse than both control groups on the Stockings of Cambridge (SOC), a neuropsychological test of planning ability, and were slower and more anxious during a categorization task. These findings suggest that specific deficits in executive functioning may be associated with the difficulties hoarding patients have organizing their possessions.     

How does mindfulness-based cognitive therapy work?

Mindfulness-based cognitive therapy (MBCT) is an efficacious psychosocial intervention for recurrent depression ( [Kuyken et?al., 2008], [Ma and Teasdale, 2004] and [Teasdale et?al., 2000]). To date, no compelling research addresses MBCT’s mechanisms of change. This study determines whether MBCT’s treatment effects are mediated by enhancement of mindfulness and self-compassion across treatment, and/or by alterations in post-treatment cognitive reactivity. The study was embedded in a randomized controlled trial comparing MBCT with maintenance antidepressants (mADM) with 15-month follow-up (Kuyken et al., 2008). Mindfulness and self-compassion were assessed before and after MBCT treatment (or at equivalent time points in the mADM group). Post-treatment reactivity was assessed one month after the MBCT group sessions or at the equivalent time point in the mADM group. One hundred and twenty-three patients with ≥3 prior depressive episodes, and successfully treated with antidepressants, were randomized either to mADM or MBCT. The MBCT arm involved participation in MBCT, a group-based psychosocial intervention that teaches mindfulness skills, and discontinuation of ADM. The mADM arm involved maintenance on a therapeutic ADM dose for the duration of follow-up. Interviewer-administered outcome measures assessed depressive symptoms and relapse/recurrence across 15-month follow-up. Mindfulness and self-compassion were measured using self-report questionnaire. Cognitive reactivity was operationalized as change in depressive thinking during a laboratory mood induction.MBCT’s effects were mediated by enhancement of mindfulness and self-compassion across treatment. MBCT also changed the nature of the relationship between post-treatment cognitive reactivity and outcome. Greater reactivity predicted worse outcome for mADM participants but this relationship was not evident in the MBCT group.MBCT’s treatment effects are mediated by augmented self-compassion and mindfulness, along with a decoupling of the relationship between reactivity of depressive thinking and poor outcome. This decoupling is associated with the cultivation of self-compassion across treatment.     

Can false memories prime problem solutions?

Previous research has suggested that false memories can prime performance on related implicit and explicit memory tasks. The present research examined whether false memories can also be used to prime higher order cognitive processes, namely, insight-based problem solving. Participants were asked to solve a number of compound remote associate task (CRAT) problems, half of which had been primed by the presentation of Deese/Roediger–McDermott (DRM) lists whose critical lure was also the solution to the problem. The results showed that when the critical lure: (a) was falsely recalled, CRAT problems were solved more often and significantly faster than problems that were not primed by a DRM list and (b) was not falsely recalled, CRAT problem solution rates and times were no different than when there was no DRM priming. A second experiment demonstrated that these outcomes were not a simple artifact of the inclusion of a recall test prior to the problem solving task. The implications of these results are discussed with regard to the previous literature on priming and the adaptive function of false memories.