Sleep-dependent consolidation of procedural motor memories in children and adults: the pre-sleep level of performance matters

In striking contrast to adults, in children sleep following training a motor task did not induce the expected (offline) gain in motor skill performance in previous studies. Children normally perform at distinctly lower levels than adults. Moreover, evidence in adults suggests that sleep dependent offline gains in skill essentially depend on the pre-sleep level of performance. Against this background, we asked whether improving children's performance on a motor sequence learning task by extended training to levels approaching those of adults would enable sleep-associated gains in motor skill in this age group also. Children (4-6 years) and adults (18-35 years) performed on the motor sequence learning task (button-box task) before and after ~2-hour retention intervals including either sleep (midday nap) or wakefulness. Whereas one group of children and adults, respectively, received the standard amount of 10 blocks of training before retention intervals of sleep or wakefulness, a further group of children received an extended training on 30 blocks (distributed across 3 days). A further group of adults received a restricted training on only two blocks before the retention intervals. Children after standard training reached lowest performance levels, whereas in adults performance after standard training was highest. Children with extended training and adults after reduced training reached intermediate performance levels. Only at these intermediate performance levels did sleep induce significant gains in motor sequence skill, whereas performance did not benefit from sleep in the low-performing children or in the high-performing adults. Spindle counts in the post-training nap were correlated with performance gains at retrieval only in the adults benefitting from sleep. We conclude that, across age groups, sleep induces the most robust gain in motor skill at an intermediate pre-sleep performance level. In low-performing children sleep-dependent improvements in skill may be revealed only after enhancing the pre-sleep performance level by extended training.     

A General Model of Preventive and Interventive Self‐Control

The field of self‐control has witnessed an unprecedented boom, not least due to the immense implications of successful and unsuccessful self‐control for people’s lives. However, successful and unsuccessful self‐control can take many different forms, and many conceptual problems have been raised as to what self‐control is about and how to best study it. Integrating different literatures, we provide a general model of self‐control which distinguishes between preventive (i.e., anticipatory) and interventive (i.e., momentary) forms of self‐control. The proposed Preventive‐Interventive Model (PI‐Model) of Self‐Control combines seven basic components: preventive strategies, desire, conflict, control motivation, volition, opportunity constraints, and behavior enactment. The resulting taxonomy helps to distinguish self‐control from standard motivational processes, to define the concept of temptation, and to identify different types of self‐control failure including self‐monitoring failure, motivational self‐control failure, and volitional self‐control failure. Further, the model helps to outline five broad mechanisms through which people may be able to proactively boost self‐control success.     

A functional model to localize the conflict underlying the stroop phenomenon

Summary A new functional response competition model to describe the cognitive processes underlying the Stroop phenomenon is proposed. The main challenge for any explanation is the asymmetry of the conflict, i.e. the fact that the meaning of the color word disturbs naming the color of an incongruent color-word-color stimulus far more than the irrelevant color disturbs reading the word. The model proposes that the organism processes both competing verbal responses by priming the relevant set and inhibiting the irrelevant set if both responses belong to different sets, and by computing internal delay-time differences if both responses belong to the same set. The model explains most of the existing data about the Stroop phenomenon and is in full accordance with present knowledge on selective attention, stimulus encoding, response selection, and psychological refractory period. It is confirmed by data of a Stroop experiment using a set of verbal color responses disjoint from the set of the stimulus color words. This experiment is based on the strategy often used in Stroop research to try to obtain a reversed Stroop effect in order to find an explanation of the Stroop effect. The data show full symmetry of competition, that is a Stroop effect and a reversed Stroop effect of about the same amount of increased reaction time.This paper is based on an experimental study conducted by Dipl.-Psych. Margrit O. Dolt under the supervision of Dr. W.R. Glaser and submitted as Diplomarbeit.     

Three ways to resist temptation: The independent contributions of executive attention, inhibitory control, and affect regulation to the impulse control of eating behavior

It is generally assumed that impulse control plays a major role in many areas of self-regulation such as eating behavior. However, the exact mechanisms that enable the control of impulsive determinants such as automatic affective reactions toward tempting stimuli are not well understood. “The present research investigated the separate moderator effects of three factors of impulse control, executive attention, inhibitory control, and affect regulation on the relationship between automatic affective reactions toward candy and subsequent candy consumption.” Results showed that all three factors reduced the influence of automatic affective reactions on eating behavior, indicating improved impulse control. Implications for self-regulation research are discussed.     

The road to the unconscious self not taken: Discrepancies between self‐ and observer‐inferences about implicit dispositions from nonverbal behavioural cues

To what extent can individuals gain insight into their own or another person's implicit dispositions' We investigated whether self‐perceivers versus neutral observers can detect implicit dispositions from nonverbal behavioural cues contained in video feedback (cue validity) and whether these cues are in turn used as a valid basis for explicit dispositional inferences (cue utilization). Across three studies in the domains of extraversion and anxiety we consistently obtained reliable cue validity and cue utilization for neutral observers but not for self‐perceivers. An additional measure of state inferences in Study 3 showed that one reason for the lack of mediation in self‐perceivers is their reluctance to use their state inferences as a basis for more general trait inferences. We conclude that people have a ‘blind spot’ with respect to the nonverbal behavioural manifestations of their unconscious selves, even though neutral observers may readily detect and utilize this information for dispositional inferences. Copyright © 2009 John Wiley & Sons, Ltd.     

Cognitive Therapy for Obsessive-Compulsive Disorder: a Case Example

Cognitive therapy for OCD is an empirically validated alternative to the more widely used and validated behavioral therapy for OCD. The cognitive approach is based on the premise that belief systems contribute importantly to the development and maintenance of all types of OCD. By identifying and challenging maladaptive thoughts, beliefs, and core beliefs, patients can improve significantly and maintain their gains over time. This approach is demonstrated in detail with the case of Caroline, a 51-year-old woman with contamination obsessions.     

Validity of the Rey Visual Design Learning Test in primary and secondary school children.

The Rey Visual Design Learning Test (Rey, 1964, cited in Spreen & Strauss, 1991, Wilhelm, 2004) assesses immediate memory span, new learning, delayed recall and recognition for nonverbal material. Two studies are presented that focused on the construct validity of the RVDLT in primary and secondary school children. In the first study, primary school children performed the RVDLT and the Biber Figural Learning Test, as well as the WISC-R Block design Test, Boston Naming Test, and the Trailmaking Test, to assess discriminant validity. In the second study, the age range was expanded and the subtest Visual Reproductions of the Wechsler Memory Scale with a Delayed recall phase was used to assess the construct validity. A test for visual-motor integration and a test for attention, concentration, and speed of information processing were also added to complete the test battery for assessing discriminant validity. Moderate to high correlations were found between scores on the RVDLT and the tests used to assess construct validity. The correlational pattern of RVDLT scores and the scores on the discriminant tests is discussed.     

Individual differences in components of reaction time distributions and their relations to working memory and intelligence

The authors bring together approaches from cognitive and individual differences psychology to model characteristics of reaction time distributions beyond measures of central tendency. Ex-Gaussian distributions and a diffusion model approach are used to describe individuals' reaction time data. The authors identified common latent factors for each of the 3 ex-Gaussian parameters and for 3 parameters central to the diffusion model using structural equation modeling for a battery of choice reaction tasks. These factors had differential relations to criterion constructs. Parameters reflecting the tail of the distribution (i.e., tau in the ex-Gaussian and drift rate in the diffusion model) were the strongest unique predictors of working memory, reasoning, and psychometric speed. Theories of controlled attention and binding are discussed as potential theoretical explanations.     

Children's initial sleep‐associated changes in motor skill are unrelated to long‐term skill levels

Sleep is considered to support the formation of skill memory. In juvenile but not adult song birds learning a tutor's song, a stronger initial deterioration of song performance over night‐sleep predicts better song performance in the long run. This and similar observations have stimulated the view of sleep supporting skill formation during development in an unsupervised off‐line learning process that, in the absence of external feedback, can initially also enhance inaccuracies in skill performance. Here we explored whether in children learning a motor sequence task, as in song‐learning juvenile birds, changes across sleep after initial practice predict performance levels achieved in the long run. The task was a serial reaction time task (SRTT) where subjects had to press buttons which were lighted up in a repeating eight‐element sequence as fast as possible. Twenty‐five children (8–12 years) practised the task in the evening before nocturnal sleep which was recorded polysomnographically. Retrieval was tested on the following morning and again 1 week later after daily training on the SRTT. As expected, changes in response speed over the initial night of sleep were negatively correlated with final performance speed after the 1‐week training. However, unlike in song birds, this correlation was driven by the baseline speed level achieved before sleep. Baseline‐corrected changes in speed or variability over the initial sleep period did not predict final performance on the trained SRTT sequence, or on different sequences introduced to assess generalization of the trained behaviour. The lack of correlation between initial sleep‐dependent changes and long‐term performance might reflect that the children were too experienced for the simple SRTT, possibly also favouring ceiling effects in performance. A consistent association found between sleep spindle activity and explicit sequence knowledge alternatively suggests that the expected correlation was masked by explicit memory systems interacting with skill memory formation.