Yoga,Mindfulness, and Meditation Interventions for Youth with ADHD: Systematic Review and Meta-Analysis

Attention-deficit/hyperactivity disorder (ADHD) is a chronic developmental disorder affecting 3–7% of children. In light of the growing utilization of yoga, mindfulness, and meditation in ADHD populations and potential benefits it has on ADHD symptoms, executive function deficits, and social functioning, we sought to evaluate these interventions for youth with ADHD. The primary aim of this review paper is to identify the efficacy of these programs for the treatment of youth with ADHD through a systematic review and meta-analysis. A systematic literature search was conducted in the following electronic databases: PsychINFO, ERIC, PubMed, and MEDLINE. Studies were included in the meta-analytic review if participants were between 5–17 years old, had a diagnosis of ADHD or met symptom threshold on psychometrically-validated measure of ADHD symptoms, was a treatment outcome study, and was published in a peer-reviewed English-language journal. The effect sizes of eleven studies demonstrate that yoga, mindfulness-based interventions, and/or meditation had a statistically significant effect on the outcomes of ADHD symptoms, hyperactivity, and inattention (parent and teacher report), as well as parent-child relationship, executive functioning, on-task behavior, parent stress, and parent trait-mindfulness (p?<?0.05). The effect sizes range from small to large effects across these outcomes. Considerable risk for bias was found across studies. Given significant methodological limitations of the literature, positive effect sizes found in studies should be interpreted with caution; these interventions should not be considered first-line interventions for ADHD. However, preliminary findings suggest yoga, mindfulness, and meditation may be beneficial for youth with ADHD, but extensive research is required to validate the efficacy of these interventions.     

The role of sparsely distributed representations in familiarity recognition of verbal and olfactory materials

We present the generalized signal detection theory (GSDT), where familiarity is described by a sparse binomial distribution of binary node activity rather than by normal distribution of familiarity. Items are presented in a distributed representation, where each node receives either noise only, or signal and noise. An old response (i.e., a “yes” response) is made if at least one node receives signal plus noise that is larger than the activation threshold, and item variability is determined by the distribution of activated nodes as the threshold is varied. A distinct representation leads to better performance and a lower ratio of new to old item variability, than a more distributed and less distinct representations. Here we apply the GSDT to empirical data on verbal and olfactory memory and suggest that verbal memory relies on a distinct neural item representation, whereas olfactory memory has a fuzzy neural representation leading to poorer memory and inducing a larger ratio of new to old item variability.     

Birth order and hand preference in chimpanzees (Pan troglodytes): implications for pathological models of handedness in humans

The effect of birth order on hand preference was assessed in a sample of 154 captive-born chimpanzees. Subjects were classified as first, middle, or latter born using 2 classification criteria based on their birth order. Hand preference was measured using a task that elicited coordinated bimanual actions. Significant birth-order effects were found for both classification criteria, with first- and latter-born subjects exhibiting a lesser degree of right-handedness compared with middle-born subjects. These data suggest that biological rather than sociological factors play a greater role in explaining the observed birth-order effects on hand preference in humans.     

An information-theory approach to geometry for animal groups

Animal Cognition - One of the hardest problems in studying animal behaviour is to quantify patterns of social interaction at the group level. Recent technological developments in global positioning...     

Genetic influence on the expression of hand preferences in chimpanzees (Pan troglodytes): evidence in support of the right-shift theory and developmental instability

Genetic mechanisms have been proposed to explain the pervasive representation of right-handedness in humans, whereas random, nongenetic factors have been posited to explain the lack of population-level right-handedness in nonhuman primates. We report evidence that hand preferences in chimpanzees are heritable, even among related individuals raised in different environments. Furthermore, we report that the degree of heritability is modified by factors associated with developmental instability, notably, offspring parity. The data are interpreted to reconcile both genetic models for handedness and hypotheses suggesting that developmental instability influences variation in handedness.     

Infant responsiveness and maternal confidence in the neonatal period

Responsiveness in prematurely and term-born infants was studied cross-sectionally in relation to maternal confidence. Orientation and arousal were measured in 140 prematurely (mean BW 1,398 g, GA 30.1 weeks) and 75 term-born infants (mean BW 3,613 g, GA 39.3 weeks) with the Neonatal Behavioral Assessment Scales. Mothers filled out the Maternal Confidence Questionnaire and a modified version of the Parenting Stress Index. Prematurely born infants had a significantly lower level of arousal than term-born neonates. Responsiveness was not associated with maternal confidence. Lower confidence was associated with primiparity in both groups of mothers. Multiparous mothers of prematurely born infants had significantly lower levels of confidence than multiparous mothers of term-born infants. Confidence was significantly associated with stress for mothers of prematurely and term-born infants, and may be focused in follow-up after giving birth. Prematurely born infants should be examined more thoroughly in aspects of arousal at the time of discharge.     

Displayed emotions and witness credibility: a comparison of judgements by individuals and mock juries

Mock juries of 5–7 jurors viewed one of three video‐recorded versions of a rape victim's testimony, role‐played by a professional actress. The statement was given in a free‐recall manner with one of three kinds of emotions displayed, termed congruent, neutral and incongruent emotional expressions. The juries were requested to reach a decision on items in a short questionnaire, probing the perceived credibility of the witness and judgements of the probability of a guilty verdict. The jurors were then asked to complete the questionnaire a second time, individually and anonymously. A control group filled out the questionnaire individually without preceding jury deliberations. When participants judged credibility and guilt independently, without a preceding jury discussion, the displayed emotions strongly influenced the judgements. However, discussions in the context of the jury strongly attenuated the effect of displayed emotion, with judgements converging on the credibility of a neutral emotional expression as judged by independent participants, and the attenuating effect outlasted the jury‐situation. The results are consistent with research within social psychology showing that social stereotypes and prejudices are often neutralised by group discussions. Copyright © 2006 John Wiley & Sons, Ltd.