The relationship between initial errorless learning conditions and subsequent performance

This experiment explores a suggestion by [Maxwell, J.P., Masters, R.S.W., Kerr, E., Weedon, E. (2001). The implicit benefit of learning without errors. Quarterly Journal of Experimental Psychology A 54, 1049-1068] that an initial bout of implicit motor learning confers beneficial performance characteristics, such as robustness under secondary task loading, despite subsequent explicit learning. Participants acquired a complex motor skill (golf putting) over 400 trials. The environment was constrained early in learning to minimize performance error. It was predicted that in the absence of explicit instruction, reducing error would prevent hypothesis testing strategies and the concomitant accrual of declarative (explicit) knowledge, thereby reducing dependence on working memory resources. The effect of an additional cognitive task on putting performance was used to assess reliance on working memory. Putting performance of participants in the Implicit-Explicit condition was unaffected by the additional cognitive load, whereas the performance of Explicit participants deteriorated. The relationship between error correction and episodic verbal reports suggested that the explicit group were involved in more hypothesis testing behaviours than the Implicit-Explicit group early in learning. It was concluded that a constrained, uninstructed, environment early in learning, results in procedurally based motor output unencumbered by disadvantages associated with working memory control.     

Age and regulatory focus determine preferences for health-related role models

The authors hypothesized that the effectiveness of role models varies across the adult life span because of differences in health-related regulatory orientations. Because young adults have strong health-related promotion orientations, they should be motivated by positive models who illustrate the benefits of good health. Because older adults have more balanced health-related promotion and prevention orientations, they should be motivated not only by positive models but also by negative models who illustrate the costs of poor health. Results indicated that both young and older adults perceived positive models to be motivating, but older adults found negative models to be more motivating than did young adults. Age differences in responses to negative models were partially mediated by differences in health-related prevention orientation.     

Preadolescent Clues to Understanding Depression in Girls

Between the ages of 10 and 15, increases in depression among girls result in a rate that is twice as high as the rate of depression in boys. This sex difference remains throughout early and middle adulthood. Prior to early adolescence, there is essentially no sex difference in the rate of depression. The aim of the present review is to examine whether the preadolescent period is a time during which precursors to depression in girls can be identified. First, existing areas of research on explaining sex differences in depression, including cognitive and affiliative style and the socialization of emotion, are reviewed. Second, the hypothesis that for some girls, preadolescent precursors to depression take the form of excessive empathy, compliance and regulation of negative emotions is articulated. Third, ways of building on existing models by including the proposed preadolescent precursors are proposed. Finally, approaches to testing the hypotheses that individual differences in these domains during preadolescence may explain later individual differences in adolescent onset depression are explored.     

Embedded figures detection in autism and typical development: preliminary evidence of a double dissociation in relationships with visual search

Individuals with autism show relatively strong performance on tasks that require them to identify the constituent parts of a visual stimulus. This is assumed to be the result of a bias towards processing the local elements in a display that follows from a weakened ability to integrate information at the global level. The results of the current study showed that, among children with autism, ability to locate a figure embedded in a larger stimulus was only related to performance on visual search trials where the target was identified by a unique perceptual feature. In contrast, control children's embedded figures performance was specifically related to their performance on visual search trials where the target was defined by a conjunction of features. This double dissociation suggests that enhanced performance on perceptual tasks by children with autism is not simply a consequence of a quantitative difference in ability to engage in global processing.     

Cortical regions associated with different aspects of object recognition performance

In the present object recognition study, we examined the relationship between brain activation and four behavioral measures: error rate, reaction time, observer sensitivity, and response bias. Subjects perceptually matched object pairs in which structural similarity (SS), an index of structural differentiation, and exposure duration (DUR), an index of task difficulty, were manipulated. The SS manipulation affected the fMRI signal in the left anterior fusiform and parietal cortices, which in turn reflected a bias to respond same. Conversely, an SS-modulated fMRI signal in the right middle frontal gyrus reflected a bias to respond different. The DUR manipulation affected the fMRI signal in occipital and posterior fusiform regions, which in turn reflected greater sensitivity, longer reaction times, and greater accuracy. These findings demonstrate that the regions most strongly implicated in processing object shape (SS-modulated regions) are associated with response bias, whereas regions that are not directly involved in shape processing are associated with successful recognition performance.     

Repetition blindness: out of sight or out of mind?

Does repetition blindness represent a failure of perception or of memory? In Experiment 1, participants viewed rapid serial visual presentation (RSVP) sentences. When critical words (C1 and C2) were orthographically similar, C2 was frequently omitted from serial report; however, repetition priming for C2 on a postsentence lexical decision task was equivalent whether or not C1 was similar to C2. In Experiment 2, participants monitored RSVP sentences for a predetermined target. Participants frequently failed to detect the target when it was preceded by an orthographically similar word. In Experiment 3, the authors investigated the role of the attentional blink in this effect. These experiments suggest that repetition blindness is a failure of conscious perception, consistent with predictions of the token-individuation hypothesis.     

Listening comprehension and working memory are impaired in attention-deficit hyperactivity disorder irrespective of language impairment

This study investigated listening comprehension and working memory abilities in children with attention-deficit hyperactivity disorder (ADHD), presenting with and without language impairments (LI). A 4-group design classified a community sample (n = 77) of boys aged 9–12 into ADHD, ADHD + LI, LI, and Normal groups. Children completed tests of basic language and cognitive skills, verbal and spatial working memory, and passage-level listening comprehension. Multivariate analyses and post hoc comparisons indicated that ADHD children who did not have co-occurring LI comprehended factual information from spoken passages as well as normal children, but were poorer at comprehending inferences and monitoring comprehension of instructions. ADHD children did not differ from normal children in verbal span, but showed significantly poorer verbal working memory, spatial span, and spatial working memory. The ADHD + LI and LI groups were most impaired in listening comprehension and working memory performance, but did not differ from each other. Listening comprehension skills were significantly correlated with both verbal and spatial working memory, and parent–teacher ratings of inattention and hyperactivity/impulsivity. Findings that children with ADHD but no LI showed subtle higher-level listening comprehension deficits have implications for both current diagnostic practices and conceptualizations of ADHD.     

The role of working memory in motor learning and performance

Three experiments explore the role of working memory in motor skill acquisition and performance. Traditional theories postulate that skill acquisition proceeds through stages of knowing, which are initially declarative but later procedural. The reported experiments challenge that view and support an independent, parallel processing model, which predicts that procedural and declarative knowledge can be acquired separately and that the former does not depend on the availability of working memory, whereas, the latter does. The behaviour of these two processes was manipulated by providing or withholding visual (and auditory) appraisal of outcome feedback. Withholding feedback was predicted to inhibit the use of working memory to appraise success and, thus, prevent the formation of declarative knowledge without affecting the accumulation of procedural knowledge. While the first experiment failed to support these predictions, the second and third experiments demonstrated that procedural and declarative knowledge can be acquired independently. It is suggested that the availability of working memory is crucial to motor performance only when the learner has come to rely on its use.     

Changes in limb stiffness under conditions of mental stress

In 2 experiments, the effects of mental stress on limb stiffness were investigated. The relative contribution to arm stiffness of individual muscle activity, co-contraction, muscle reflexes, and postural adjustments were examined. In each experiment, participants (N = 24, Experiment 1; N = 16, Experiment 2) held their supinated hand under a tray that they were required to return to horizontal after it had been suddenly released. Electromyographic activity in the biceps and triceps muscles was recorded, as were elbow and wrist angles and tray displacement. In Experiment 1, mental arithmetic stress was shown to lead to decreased tray displacement (i.e., increased resistance) compared with displacements under the control, unstressed condition, as well as to increased elbow flexion before tray release. In Experiment 2, the increased resistance to perturbation caused by mental stress was found to be independent of initial elbow angle, but to vary as a function of the amount of upward force exerted before tray release. The authors conclude that stress-induced increases in limb stiffness result from changes in the initial position of the elbow, specified by its angle, together with the initial force exerted by participants to counteract the mechanical perturbations.     

The Effect of Inhibition of Return on Lexical Access

Abstract—Inhibition of return refers to a bias against returning attention to a location or object that has been recently attended. Recent research has shown that inhibition of return can be found not only in simple detection tasks, but also in tasks requiring relatively simple discrimination judgments. The present experiments examined whether inhibition of return occurs in tasks that require complex discriminations such as lexical decision and categorization tasks. Not only was inhibition of return found in both experiments, but a greater amount of inhibition was found for low-frequency words than for high-frequency words. These findings suggest that inhibition of return not only inhibits returning attention to previously attended locations, but can also affect the processing that is required for lexical access.