Effect of stride length on overarm throwing delivery: A linear momentum response

Changing stride length during overhand throwing delivery is thought to alter total body and throwing arm linear momentums, thereby altering the proportion of throwing arm momentum relative to the total body. Using a randomized cross-over design, nineteen pitchers (15 collegiate and 4 high school) were assigned to pitch two simulated 80-pitch games at ±25% of their desired stride length. An 8-camera motion capture system (240 Hz) integrated with two force plates (960 Hz) and radar gun tracked each throw. Segmental linear momentums in each plane of motion were summed yielding throwing arm and total body momentums, from which compensation ratio’s (relative contribution between the two) were derived. Pairwise comparisons at hallmark events and phases identified significantly different linear momentum profiles, in particular, anteriorly directed total body, throwing arm, and momentum compensation ratios (P ⩽ .05) as a result of manipulating stride length. Pitchers with shorter strides generated lower forward (anterior) momentum before stride foot contact, whereas greater upward and lateral momentum (toward third base) were evident during the acceleration phase. The evidence suggests insufficient total body momentum in the intended throwing direction may potentially influence performance (velocity and accuracy) and perhaps precipitate throwing arm injuries.     

Women’s hair as a cue to desired relationship and parenting characteristics

We investigated how women’s hair color (blond, brown, black) and length (short, medium, long) influences males’ judgments about the women’s age, health, physical attractiveness, relationship potential, and parenting capability. Results, which are generally consistent with evolutionary psychology approaches, indicate that hair color and, to a lesser extent, length can affect perceptions of personal characteristics. More specifically, we found that lighter hair (blond and brown) compared to darker hair (black) is generally associated with perceptions of youth, health and attractiveness, and generally leads to more positive perceptions of relationship and parenting potential. Furthermore, the relationships between variables suggest that characteristics directly related to reproductive potential may be inferred from more obvious indirect characteristics. These results suggest that males are able to make complex judgments about women concerning their desirable relationship and parenting potential based on discernable characteristics such as hair color and length.     

Can Facebook Informational Use Foster Adolescent Civic Engagement?

The findings on the association between Social Networking Sites and civic engagement are mixed. The present study aims to evaluate a theoretical model linking the informational use of Internet‐based social media (specifically, Facebook) with civic competencies and intentions for future civic engagement, taking into account the mediating role of civic discussions with family and friends and sharing the news online. Participants were 114 Italian high school students aged 14–17 years (57 % boys). Path analysis was used to evaluate the proposed theoretical model. Results showed that Facebook informational use was associated with higher levels of adolescent perceived competence for civic action, both directly and through the mediation of civic discussion with parents and friends (offline). Higher levels of civic competencies, then, were associated with a stronger intention to participate in the civic domain in the future. Our findings suggest that Facebook may provide adolescents with additional tools through which they can learn civic activities or develop the skills necessary to participate in the future.     

Worry and Sleep Length Revisited: Worry,Sleep Length,and Sleep Disturbance Ascribed to Worry

The author administered university students (N = 222; 152 women, 70 men) the Worry Domains Questionnaire (F. Tallis, G. C. L. Davey, & A. Bond, 1994) and a newly constructed scale (the Sleep Disturbance Ascribed to Worry Scale) to measure sleep disturbance attributed to worry. To revisit previous studies (i.e., E. Hartmann, F. Baekeland, & G. R. Zwilling, 1972; S. J. H. McCann & L. L. Stewin, 1988) that suggested that sleep length was positively related to worry, the author also asked the students a question about habitual sleep length. The results indicated that worry and sleep disturbance attributed to worry were negatively related to sleep length. A regression analysis revealed that worry was significantly negatively related to habitual sleep length irrespective of sleep disturbance ascribed to worry.     

The Elusive General Factor of Personality: The Acquaintance Effect

A general factor (g_p) at the apex of personality has been suggested to account for the correlations between the Big Five. Although the g_p has received ample support from monomethod studies, results from studies incorporating different methods have remained rather ambiguous; some have identified a g_p across different informants, whereas others have not. It was hypothesized that these divergent findings are a result of varying lengths of acquaintance between raters. To this end, the current study presents a multitrait multi‐informant meta‐analysis (total N = 11 941) that found weak support for a g_p as a substantive trait of personality. Evidence for a g_p was susceptible to the length of acquaintance between informants. Although a g_p could be identified for short‐term acquaintances, it remained elusive at long‐term acquaintance. Thus, the g_p in other ratings more likely reflects normative ratings of an average individual rather than ratings of the specific target person. Copyright © 2013 European Association of Personality Psychology     

Changes in illness-related cognitions rather than distress mediate improvements in irritable bowel syndrome (IBS) symptoms and disability following a brief cognitive behavioural therapy intervention

Objective

A previous randomised controlled trial demonstrated that a cognitive behavioural therapy (CBT) self-management intervention significantly improved irritable bowel syndrome (IBS) symptoms and disability compared to treatment as usual (TAU). The current study analysed additional data to establish whether; 1) cognitive, behavioural and emotional factors hypothesized to perpetuate IBS symptoms and disability changed following CBT and, 2) ascertain if changes in these factors over the intervention period mediated treatment effects 6-months later.

Method

IBS patients (CBT = 31, TAU = 33) completed measures pre-and-post intervention including: Brief Illness Perception Questionnaire, Hospital Anxiety & Depression Scale and Cognitive and Behavioural Responses to Symptoms Questionnaire. Path models were evaluated to determine whether changes in cognitive and behavioural factors over the treatment period mediated treatment effects.

Results

Compared to TAU, CBT patients showed significant positive changes on several cognitive variables but not anxiety and depression following intervention. Positive change in illness perceptions following intervention mediated the treatment effect on improved IBS symptom severity and social adjustment six months later. Changes in damaging beliefs mediated the effect on social adjustment.

Conclusions

Change in cognition rather than mood mediated treatment related improvements. Changing negative perceptions of IBS appears to be a particularly important treatment mechanism.     

Does working memory change with age? The interactions of concurrent articulation with the effects of word length and acoustic confusion

ABSTRACT

The effects of acoustic confusion (phonological similarity), word length, and concurrent articulation (articulatory suppression) are cited as support for Working Memory's phonological loop component (e.g., Baddeley, 2000 Baddeley, A. D. 2000. The phonological loop and irrelevant speech effect: Some comments on Neath. Psychonomic Bulletin and Review, 7: 544–549. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar], Psychonomic Bulletin and Review, 7, 544). Research has focused on younger adults, with no studies examining whether concurrent articulation reduces the word length and acoustic confusion effects among older adults. In the current study, younger and older adults were given lists of similar and dissimilar letters (Experiment 1) or long and short words (Experiment 2) for immediate serial reconstruction of order. Items were presented visually or auditorily, with or without concurrent articulation. As expected, younger and older adults demonstrated effects of acoustic confusion, word length, and concurrent articulation. Further, concurrent articulation reduced the effects of acoustic confusion and word length equally for younger and older adults. This suggests that age-related differences occur in overall performance, but do not reflect an age-related deficiency in the functioning of the phonological loop component of working memory.