The Effects of a Physical Education Intervention Program on the Bone Properties of Second- and Third-Grade Pupils: A Cluster Randomized Controlled Trial.

BACKGROUND: Many young children do not participate in sufficient physical activity for promoting optimal bone growth. The objective of this study was to investigate the effect of young children who participated in a school-based intervention program on bone properties. The program included structured physical activity, with a focus on the application of mechanical loads on the upper and lower limbs. METHODS: A cluster randomized controlled trial was conducted, in which classes were randomly assigned to the intervention or control groups. A total of 295 (50.17% girls) children from the second and third grades from 12 classes in Israel were randomly allocated to an intervention consisting of three 10-minute weekly medium- to high-intensity activities throughout one academic year or to a treatment as usual control group. Bone properties were measured at the distal radius and tibia shaft using speed of sound, before and after the intervention. RESULTS: Distal radius properties improved significantly for both boys and girls in the intervention group (boys: meanpre = 3769.95, meanpost = 3875.08, Δ = 2.80%; girls: meanpre = 3766.27, meanpost = 3890.83, Δ = 3.30%; d = 1.03); whereas, tibia shaft properties only significantly improved for boys (meanpre = 3663.98, meanpost = 3732.75, Δ = 1.90%; d = 1). CONCLUSIONS: These findings indicate that distal radius properties of children can be positively affected by a short, easy to implement intervention program that does not require special resources.

Not sensitive, yet less biased: A signal detection theory perspective on mindfulness, attention, and recognition memory.

The practice of mindfulness has been argued to increase attention control and improve memory performance. However, it was recently suggested that the effect of mindfulness on memory may be due to a shift in response-bias, rather than to an increase in memory-sensitivity. The present study examined the mindfulness-attention-memory triad. Participants filled in the five-facets of mindfulness questionnaire, and completed two recognition blocks; in the first attention was full, whereas in the second attention was divided during the encoding of information. It was found that the facet of non-judging (NJ) moderated the impact of attention on memory, such that responses of high NJ participants were less biased and remained constant even when attention was divided. Facets of mindfulness were not associated with memory sensitivity. These findings suggest that mindfulness may affect memory through decision making processes, rather than through directing attentional resources to the encoding of information.

Mindfulness and False-Memories: The Impact of Mindfulness Practice on the DRM Paradigm.

Mindfulness practice is the cultivation of awareness to the present moment and has been shown in recent years to have beneficial effects on cognition. However, to date, the data regarding the impact of mindfulness on memory--and specifically on memory distortions--is scarce and incomplete. The present study was aimed to examine whether mindfulness practice would have an effect on true and false memories. To this end, the effect of mindfulness meditation practice on memory performance was examined in two experiments in which false memories were provoked using the Deese-Roediger-McDermott (DRM) paradigm (Roediger & McDermott, 1995). In Experiment 1, college students were randomly divided into either a 5-week mindfulness-practice group (n = 29) or a waitlist control group (n = 22). In Experiment 2, college students were randomly divided into either a brief mindfulness session (n = 21) or a mind-wandering control group (n = 19). The results indicated that mindfulness increased the recognition of true memories with no effect on spontaneous false-memories, yet increased the rate of provoked false-memories. These findings are discussed in terms of memory sensitivity and response bias, and it is argued that mindfulness may have a lesser effect on encoding processes than previously suggested.

Recollection-Based Retrieval Is Influenced by Contextual Variation at Encoding but Not at Retrieval.

In this article, we investigated the effects of variations at encoding and retrieval on recollection. We argue that recollection is more likely to be affected by the processing that information undergoes at encoding than at retrieval. To date, manipulations shown to affect recollection were typically carried out at encoding. Therefore, an open question is whether these same manipulations would also affect recollection when carried out at retrieval, or whether there is an inherent connection between their effects on recollection and the encoding stage. We therefore manipulated, at either encoding or retrieval, fluency of processing (Experiment 1)-typically found not to affect recollection-and the amount of attentional resources available for processing (Experiments 2 and 3)-typically reported to affect recollection. We found that regardless of the type of manipulation, recollection was affected more by manipulations carried out at encoding and was essentially unaffected when these manipulations were carried out at retrieval. These findings suggest an inherent dependency between recollection-based retrieval and the encoding stage. It seems that because recollection is a contextual-based retrieval process, it is determined by the processing information undergoes at encoding-at the time when context is bound with the items-but not at retrieval-when context is only recovered.