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Previous work from our lab has shown that basal cortisol levels are different between healthy young adults who spontaneously use caudate nucleus-dependent response strategies compared to young adults who use hippocampus-dependent spatial navigation strategies. Young adults who use caudate nucleus dependent strategies display lower basal cortisol levels compared to those who use hippocampus-dependent strategies. In the current study, we assessed navigation strategies in children using a virtual navigation task and measured cortisol at baseline as well as cortisol reactivity to both a psychological and to a physical stressor. Replicating what is observed in adults, we found that children who used caudate nucleus-dependent navigation strategies displayed lower cortisol levels at baseline compared to those who used hippocampus-dependent strategies. The psychological stressor, knowledge that a blood draw would be performed by a nurse, caused a significant increase in cortisol uniquely in response learners. The physical stressor, the actual blood draw, produced a significant increase in cortisol amongst spatial learners that was then comparable to levels observed in response learners. Lower baseline cortisol and higher cortisol psychological stress response observed amongst children who used response strategies may therefore reflect early biological changes during development which may have an impact later in life when considering risk for neuropsychiatric disorders.

1. Introduction Olfaction is an important food cue that enhances motivation to seek food and contributes to feeding by influencing taste and food palatability (Blundell et al. 2010; Rolls 2005; [...], Olfaction contributes to feeding behaviour and is modulated by changes in dopamine levels. Methylphenidate (MPH) increases brain dopamine levels and has been shown to reduce appetite and promote weight loss in patients with attention deficit hyperactivity disorder. The objectives of this study were to test the effect of MPH on olfaction, appetite, energy intake, and body weight (BW) on individuals with obesity. In a randomized, double-blind study, 12 participants (age 28.9 [+ or -] 6.7 years) with a body mass index (BMI) of 36.1 [+ or -] 4.5 kg/[m.sup.2] were assigned to MPH (0.5 mg/kg) (n = 5) or placebo (n = 7) twice daily for 2 months. Appetite (visual analog scale), odour threshold (Sniffin' Sticks[R]), energy intake (food menu), and BW (DEXA scan) were measured at day 1 and day 60. MPH intake significantly increased odour threshold scores (6.3 [+ or - ] 1.4 vs. 9.4 [+ or -] 2.1 and 7.9 [+ or -] 2.3 vs. 7.8 [+ or -] 1.9, respectively; p = 0.029) versus placebo. There was a significantly greater suppression of appetite sensations (desire to eat (p = 0.001), hunger (p = 0.008), prospective food consumption (p = 0.003)) and an increase in fullness (p = 0.028) over time in the MPH versus placebo. MPH suppressed appetite and improved olfactory sensitivity in individuals with obesity. These data provide novel findings on the favourable effects of MPH on appetite and weight regulation in individuals living with obesity. Key words: methylphenidate, olfaction, appetite, weight loss, energy intake, obesity. L'olfaction participe aux comportements alimentaires et se module par des variations des taux de dopamine. Le methylphenidate (MPH) entraine une augmentation des taux de dopamine dans le cerveau et on a montre qu'il entraine une diminution de l'appetit et qu'il favorise la perte de poids chez les patients presentant un trouble de deficit de l'attention avec hyperactivite. Cette etude avait pour objectif d'evaluer l'effet du MPH sur l'olfaction, l'appetit, l'apport energetique et la masse corporelle (MC) chez les personnes obeses. Dans le cadre d'une etude a double insu nous avons reparti aleatoirement 12 participants (ages de 28,9 [+ or -] 6,7 ans) avec un indice de MC eleve (IMC de 36,1 [+ or -] 4,5 kg/[m.sup.2]) dans un groupe MPH (0,5 mg/kg) (n = 5) ou placebo (n = 7) deux fois par jour pendant 2 mois. Nous avons mesure l'appetit (echelle visuelle analogue), les seuils d'odeur (Sniffin' Sticks[R]), l'apport alimentaire (menu) et la MC (scan DEXA) aux jours 1 et 60. Les resultats ont montre que l'absorption de MPH entraine une augmentation plus marquee des scores de seuils d'odeur (6,3 [+ or -] 1,4 vs 9,4 [+ or -] 2,1 et 7,9 [+ or -] 2,3 vs 7,8 [+ or -] 1,9, respectivement; p = 0,029) qu'avec le placebo. Nous avons observe une inhibition nettement plus elevee des sensations d'appetit (desir de s'alimenter (p = 0,001), faim (p = 0,008), consommation d'aliments prospective (p = 0,003)) et de la sensation de satiete (p = 0,028) en fonction du temps dans le groupe MPH qu'avec le placebo. En conclusion, le MPH entrainait une inhibition de l'appetit et permettait d'ameliorer la sensibilite olfactive chez les personnes obeses. Ces donnees apportent de nouveaux resultats quant aux effets favorables du MPH sur l'appetit et la regulation du poids chez les personnes aux prises avec l'obesite. [Traduit par la Redaction] Mots-cles : methylphenidate, olfaction, appetit, perte de poids, apport energetique, obesite.

Objectives: To understand why some long-term childhood cancer survivors experience positive adjustment in the long run,[Q1] this study aimed to (1) explore associations between well-being, health status, social support, and emotion regulation (ER) strategies in a cohort of long-term childhood lymphoblastic leukemia (cALL) survivors, (2) identify the individual contribution of each ER strategy to well-being (3) and their interaction with social support. Methods: We used data from 92 participants from the PETALE cohort (51% female, aged 24 ± 7 years). Measures included well-being (WHO-5), health status (15D), social support (SSQ-6), cognitive reappraisal and expressive suppression (ERQ), and emotional processing and expression (EAC). We modeled the odds of high well-being adjusting for health status in logistic regressions and explored the moderating role of social support with bootstrap techniques. Independent of clinical history, high well-being was associated with better health status, higher social support, more frequent use of cognitive reappraisal and emotional processing. Results: We found a main contribution of emotional processing to well-being (OR = 2.12, 95% CI = 1.09-5.37). The interaction between low suppression and high social support was significant (OR =.40, 95% CI =.13-.79). Probabilities for high well-being were 96% when expressive suppression was low and social support was high. Results suggest approaching one's own emotions may contribute to well-being in long-term childhood cancer survivors. Clinical implications: Combining curbing emotional suppression with promoting supportive social environment could be a promising target for future supportive care interventions in survivors. [ABSTRACT FROM AUTHOR]

Methylphenidate (MPH) has been previously shown to increase resting energy expenditure (REE) in individuals of normal weight; however, the effects on individuals living with obesity are currently unknown. Ten individuals living with obesity were randomly assigned to undergo 60 days of MPH administration with a daily dose of 0.5 mg/kg body weight or a placebo control. REE was measured before and after the 60‐day intervention. There was a trend toward significance for group × time interaction on REE (p = 0.082) with a large effect size (η2 = 0.331), with MPH administration increasing REE compared to a decrease in placebo control. Preliminary findings from this pilot study show that MPH has the potential to counter the adaptive thermogenic process commonly seen in weight loss. This is a unique finding among pharmacotherapies, as no approved obesity drugs measurably impact REE. [ABSTRACT FROM AUTHOR]

This study tested whether the association between temporal processing (TP) and reading is mediated by phonological awareness (PA) in a normative sample of 615 eight-year-olds. TP was measured with auditory and bimodal (visual-auditory) temporal order judgment tasks and PA with a phoneme deletion task. PA partially mediated the association between both auditory and bimodal TP and reading, above nonverbal abilities, vocabulary, and processing speed. PA explained a larger proportion of the association between auditory TP and reading (56% vs. 39% for bimodal TP), and most of the association between bimodal TP and reading was direct. This finding is consistent with a dual--phonological and visual--pathway model of the association between TP and reading in normative reading skills. (Contains 5 tables and 2 figures.)

Objective: To distinguish Cuban children clinically referred because of ADHD from an at-risk community sample and a community control group in terms of symptoms, associated difficulties and impairment of family and peer relations. Method: Parents and teachers of 1,036 children (6-8 years old) completed an established ADHD rating scale and a behavioral screening measure, including peer functioning.We also administered a structured clinical interview and measures of family impairment to the clinical sample and to an at-risk community-based subsample. Results: Although both clinical and at-risk groups displayed more externalizing and internalizing symptoms than controls, referred children were not only characterized by higher levels of ADHD symptoms, but also by greater impairment of family and peer relations than at-risk community children or community controls. Conclusion: The findings suggest that ADHD has major consequences on the family and peer functioning of Cuban children, which may lead to their referral for treatment. (Contains 1 note and 3 tables.)

Pharmacogenetics holds the promise of minimizing adverse neurodevelopmental outcomes of cancer patients by identifying patients at risk, enabling the individualization of treatment and the planning of close follow-up and early remediation. This review focuses first on methotrexate, a drug often implicated in neurotoxicity, especially when used in combination with brain irradiation. The second focus is on glucocorticoids that have been found to be linked to adverse developmental effects in relation with the psychosocial environment. For both examples, we review how polymorphisms of genes encoding enzymes involved in specific mechanisms of action could moderate adverse neurodevelopmental consequences, eventually through common final pathways such as oxidative stress. We discuss a multiple hit model and possible strategies required to rise to the challenge of this integrative research.

We used variations of the stop signal task to study two components of motor response inhibition--the ability to withhold a strong response tendency (restraint) and the ability to cancel an ongoing action (cancellation)--in children with a diagnosis of attention deficit hyperactivity disorder (ADHD) and in non-ADHD controls of similar age (ages 7-14 years). The goal was to determine if restraint and cancellation were related and if both were deficient in ADHD. The stop signal task involved a choice reaction time task (go task) which required a rapid response. The demand for inhibitory control was invoked through the presentation of a stop signal on a subset of go trials which required that the ongoing response be suspended. The stop signal was presented either concurrently with the go signal (restraint version) or after a variable delay (cancellation version). In Study 1, we compared ADHD and control children on the cancellation version of the stop task; in Study 2, we compared ADHD and controls on the restraint version. In Study 3, a subset of ADHD and control participants completed both tasks so that we could examine convergence of these dimensions of inhibition. Compared to control participants, ADHD participants showed a deficit both in the ability to cancel and to restrain a speeded motor response. Performance on the restraint version was significantly correlated with performance on the cancellation version in controls, but not in ADHD participants. We conclude that ADHD is associated with deficits in both restraint and cancellation subcomponents of inhibition.

Evaluated contributions of birth status (gestational age and birthweight) and family adversity at birth and at age 7 to explain behavior problems at age 7. Found significant relationships between birth status and isolation, social withdrawal problems, social immaturity, and inattention. Family adversity at birth contributed to aggression reported by three sources whereas, at age 7, this index related only to parent-reported aggression and social immaturity. (Author/KB)