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Persistent, long-term cerebral white matter changes after sports-related repetitive head impacts

Introduction Repetitive head impacts (RHI) sustained in contact sports are thought to be necessary for the long-term development of chronic traumatic encephalopathy (CTE). Our objectives were to: 1) characterize the magnitude and persistence of RHI-induced white matter (WM) changes; 2) determine their relationship to kinematic measures of RHI; and 3) explore their clinical relevance. Methods Prospective, observational study of 10 Division III college football players and 5 non-athlete controls during the 2011-12 season. All subjects underwent diffusion tensor imaging (DTI), physiologic, cognitive, and balance testing at pre-season (Time 1), post-season (Time 2), and after 6-months of no-contact rest (Time 3). Head impact measures were recorded using helmet-mounted accelerometers. The percentage of whole-brain WM voxels with significant changes in fractional anisotropy (FA) and mean diffusivity (MD) from Time 1 to 2, and Time 1 to 3 was determined for each subject and correlated to head impacts and clinical measures. Results Total head impacts for the season ranged from 431–1,850. No athlete suffered a clinically evident concussion. Compared to controls, athletes experienced greater changes in FA and MD from Time 1 to 2 as well as Time 1 to 3; most differences at Time 2 persisted to Time 3. Among athletes, the percentage of voxels with decreased FA from Time 1 to 2 was positively correlated with several helmet impact measures. The persistence of WM changes from Time 1 to 3 was also associated with changes in serum ApoA1 and S100B autoantibodies. WM changes were not consistently associated with cognition or balance. Conclusions A single football season of RHIs without clinically-evident concussion resulted in WM changes that correlated with multiple helmet impact measures and persisted following 6 months of no-contact rest. This lack of WM recovery could potentially contribute to cumulative WM changes with subsequent RHI exposures.

The effects of maternal parenting style and religious commitment on self-regulation, academic achievement, and risk behavior among African-American parochial college students *

This study explored relations between religiosity, both parent and student, and maternal parenting style and student academic self-regulation, academic achievement, and risk behavior among African-American youth attending a parochial college. Eighty-five students completed self-report survey measures of religiosity, self-regulation, academic achievement, and risk behavior. Participants also completed youth report measures of parental religiosity and perceived maternal parenting style. Correlational analyses show authoritative parenting to be associated with high levels of academic performance and study skills. Additional correlations revealed that highly religious students tend to perform well academically, study better, and engage in fewer risk behaviors than youth less committed to religion. Although no direct relations were observed between parenting style and student religiosity, maternal parenting style was found to moderate relations between parental and student religiosity. Findings are discussed in terms of their relevance to the population studied.

Social???cognitive correlates of protective drinking behaviors and alcohol-related consequences in college students

Although heavy episodic drinkers are at risk to experience alcohol-related consequences, studies show that a large percentage of student drinkers do not experience problems as a result of their drinking. The present study was a more in-depth examination of factors beyond just drinking quantity and frequency to explain why students experience consequences. The current research examined the relationship between the use of protective behaviors, alcohol use, and alcohol related consequences, as well as the relationship between attitudinal and cognitive predictors of engaging in protective behaviors when drinking. We hypothesized there would be a significant direct effect of protective behaviors on consequences after taking into account the effect of alcohol use and that cognitive predictors, including perceived self-efficacy, perceived effectiveness, and subjective norm, would be associated with the attitude and frequency of engaging in protective behaviors. Results supported both hypotheses, indicating good model fit for all models and significant paths between constructs (ps<.05). These findings extend the literature on protective behaviors by providing insight as to their utility in preventing harm and why students choose to engage in these behaviors. Implications for interventions are also discussed.

Single-Family Room Care and Neurobehavioral and Medical Outcomes in Preterm Infants

OBJECTIVE: To determine whether a single-family room (SFR) NICU, including factors associated with the change to a SFR NICU, is associated with improved medical and neurobehavioral outcomes. METHODS: Longitudinal, prospective, quasi-experimental cohort study conducted between 2008 and 2012 comparing medical and neurobehavioral outcomes at discharge in infants born <1500 g. Participants included 151 infants in an open-bay NICU and 252 infants after transition to a SFR NICU. Structural equation modeling was used to determine the role of mediators of relations between type of NICU and medical and neurobehavioral outcomes. RESULTS: Statistically significant results (all Ps ≤.05) showed that infants in the SFR NICU weighed more at discharge, had a greater rate of weight gain, required fewer medical procedures, had a lower gestational age at full enteral feed and less sepsis, showed better attention, less physiologic stress, less hypertonicity, less lethargy, and less pain. NICU differences in weight at discharge, and rate of weight gain were mediated by increased developmental support; differences in number of medical procedures were mediated by increased maternal involvement. NICU differences in attention were mediated by increased developmental support. Differences in stress and pain were mediated by maternal involvement. Nurses reported a more positive work environment and attitudes in the SFR NICU. CONCLUSIONS: The SFR is associated with improved neurobehavioral and medical outcomes. These improvements are related to increased developmental support and maternal involvement.

Motivation rulers for smoking cessation: a prospective observational examination of construct and predictive validity

BackgroundAlthough popular clinically, the psychometric properties of motivation rulers for tobacco cessation are unknown. This study examined the psychometric properties of rulers assessing importance, readiness, and confidence in tobacco cessation.MethodsThis observational study of current smokers was conducted at 10 US emergency departments (EDs). Subjects were assessed during their ED visit (baseline) and reassessed two weeks later. We examined intercorrelations between the rulers as well as their construct and predictive validity. Hierarchical multinomial logistic regressions were used to examine the rulers’ predictive ability after controlling for covariables.ResultsWe enrolled 375 subjects. The correlations between the three rulers ranged from 0.50 (between Important and Confidence) to 0.70 (between Readiness and Confidence); all were significant (p < 0.001). Individuals in the preparation stage displayed the highest motivation-ruler ratings (all rulers F 2, 363 ≥ 43; p < 0.001). After adjusting for covariables, each of the rulers significantly improved prediction of smoking behavior change. The strength of their predictive ability was on par with that of stage of change.ConclusionOur results provide preliminary support for the psychometric soundness of the importance, readiness, and confidence rulers.

Examining the relationships between prenatal methamphetamine exposure, early adversity, and child neurobehavioral disinhibition.

Methamphetamine use is a growing problem among pregnant women in the United States. Many negative consequences of methamphetamine use have been documented for the users, but little research has examined the long-term association between prenatal methamphetamine exposure (PME) and childhood outcomes. The current study examined the extent to which PME was predictive of childhood neurobehavioral disinhibition (ND), as well as the extent to which early adversity mediated this relationship. A sample of 320 mother-infant dyads (162 PME) was followed from birth through 6.5 years of age. ND was conceptualized as a two factor model consisting of deficits in (a) behavioral and emotional control, and (b) executive function. PME was associated with behavioral and emotional control at 5 years, which was associated with executive function deficits at 6.5 years. Early adversity (birth through year 3) significantly mediated the relationship between PME and ND. Associations with previous research and implications for prevention are discussed.

Preventing skin cancer in college females: heterogeneous effects over time.

OBJECTIVES To evaluate the effects of an appearance-focused intervention to reduce the risk of skin cancer by decreasing indoor tanning, examine potential heterogeneity in tanning across this time, and correlate the subtypes with predictors collected at baseline. DESIGN Randomized controlled trial with 379 female college students measured at 6 monthly time points. MAIN OUTCOME MEASURE Self-reported indoor tanning frequency. RESULTS The intervention was effective at decreasing tanning over the period between the fall and spring. Longitudinal latent class analysis found 3 patterns of tanners among the treatment individuals: abstainers, moderate tanners, and heavy tanners. These classes appeared in both the treatment and control conditions, and the intervention had a harm reduction effect by reducing levels of exposure within the moderate and heavy tanner classes. Participant age and self-reported tanning patterns were found to be predictive of class membership. CONCLUSIONS This research suggests that brief intervention approaches can be effective at reducing risk for skin cancer and illustrates several ways in which these protective effects can be enhanced.

Concussions Are Associated With Decreased Batting Performance Among Major League Baseball Players

Background: Concussions impair balance, visual acuity, and reaction time—all of which are required for high-level batting performance—but the effects of concussion on batting performance have not been reported. The authors examined this relationship between concussion and batting performance among Major League Baseball (MLB) players. Hypothesis: Batting performance among concussed MLB players will be worse upon return to play than batting performance among players missing time for noninjury reasons. Study Design: Cohort study; Level of evidence, 3. Methods: The authors identified MLB players who sustained a concussion between 2007 and 2013 through league disabled-list records and a Baseball Prospectus database. For a comparison group, they identified players who went on paternity or bereavement leave during the same period. Using repeated-measures generalized linear models, the authors compared 7 batting metrics between the 2 groups for the 2 weeks upon return, as well as 4 to 6 weeks after return, controlling for pre-leave batting metrics, number of days missed, and position. Results: The authors identified 66 concussions and 68 episodes of bereavement/paternity leave to include in the analysis. In the 2 weeks after return, batting average (.235 vs .266), on-base percentage (.294 vs .326), slugging percentage (.361 vs .423), and on-base plus slugging (.650 vs .749) were significantly lower among concussed players relative to the bereavement/paternity leave players (time × group interaction, P < .05). In weeks 4 to 6 after leave, these metrics were slightly lower in concussed players but not statistically significantly so. Conclusion: Although concussed players may be asymptomatic upon return to play, the residual effects of concussion on the skills required for batting may still be present. Further work is needed to clarify the mechanism through which batting performance after concussion is adversely affected and to identify better measures to use for return-to-play decisions.

Attention and word learning in autistic, language delayed, and typically developing children

Previous work has demonstrated that patterns of social attention hold predictive value for language development in typically developing infants. The goal of this research was to explore how patterns of attention in autistic, language delayed, and typically developing children relate to early word learning and language abilities. We tracked patterns of eye movements to faces and objects while children watched videos of a woman teaching them a series of new words. Subsequent test trials measured participants‘ recognition of these novel word-object pairings. Results indicated that greater attention to the speaker‘s mouth was related to higher scores on standardized measures of language development for autistic and typically developing children (but not for language delayed children). This effect was mediated by age for typically developing, but not autistic children. When effects of age were controlled for, attention to the mouth among language delayed participants was negatively correlated with standardized measures of language learning. Attention to the speaker‘s mouth and eyes while she was teaching the new words was also predictive of faster recognition of those words among autistic children. These results suggest that language delays among children with autism may be driven in part by aberrant social attention, and that the mechanisms underlying these delays may differ from those in language delayed participants without autism.

The contributions of early adverse experiences and trajectories of respiratory sinus arrhythmia on the development of neurobehavioral disinhibition among children with prenatal substance exposure.

Neurobehavioral disinhibition (ND) is a complex condition reflecting a wide range of problems involving difficulties with emotion regulation and behavior control. Respiratory sinus arrhythmia (RSA) is a physiological correlate of emotion regulation that has been studied in a variety of at-risk populations; however, there are no studies of RSA in children with ND. Data were drawn from a prospective longitudinal study of prenatal substance exposure that included 1,073 participants. Baseline RSA and RSA reactivity to an attention-demanding task were assessed at 3, 4, 5, and 6 years. ND was assessed at ages 8/9, 11, and 13/14 years via behavioral dysregulation and executive dysfunction composite measures. Greater exposure to early adversity was related to less RSA reactivity at 3 years, increases in RSA reactivity from ages 3 to 6 years, and increased behavioral dysregulation from ages 8/9 to 13/14. RSA reactivity was examined as a moderator of the association between early adversity and changes in ND. A significant Early Adversity × RSA Reactivity quadratic interaction revealed that children with decelerations in RSA reactivity exhibited increases in behavioral dysregulation, regardless of their exposure to early adversity. However, greater exposure to early adversity was related to greater increases in behavioral dysregulation, but only if children exhibited accelerations in RSA reactivity from ages 3 to 6 years. The results contribute to our understanding of how interactions across multiple levels of analysis contribute to the development of ND.