No description available.

No description available.

No description available.

No description available.

No description available.

This study examined links of cumulative and present depressive symptoms with present cortisol diurnal profiles in oldest-old adults. Five waves of data from 50 older adults (M age = 89.05 years; 64% women) who participated in the Australian Longitudinal Study of Ageing were used to combine 15 years of longitudinal data with seven cortisol samples per day over a one-week period. Findings revealed that individuals with more past depressive symptoms showed a lower cortisol awakening response (CAR). Interestingly, present depressive symptoms were not associated with the CAR. These findings inform our understanding of distal health factors in very old age.

While both social information processing and cortisol secretion in childhood aggression have generated a great deal of interest and research in the past few decades, these social-cognitive and physiological components of aggressive behavior have not been examined in the context of an integrative model. This lack of an integrative framework may underlie some of the inconsistencies that have plagued the literature in this area to date, especially with respect to hypothalamic-pituitary-adrenal (HPA) axis functioning in aggressive children. This investigation tested a mediational model of the relationship between social-information processing, cortisol secretion, and reactive and proactive aggression. Specifically, it was hypothesized that social-information processing variables would mediate the proposed relationship between reactive and proactive aggression and cortisol secretion. One hundred and twenty-six children between the ages of 13 and 18 were administered the Child Behavior Rating Form (CBR), the Home Interview with Child (HIC), the Response Decision and Social Goals Instrument (RDSGI), the Antisocial Processes Screening Device (APSD), the Buss-Durkee Hostility Inventory (BDHI), the Children's Depression Inventory (CDI), and the Revised Children's Manifest Anxiety Scale (RCMAS). Each child also contributed two samples of saliva for cortisol assay, and each child's teacher completed a teacher-version of the APSD and the CBR. Regression analyses revealed no significant associations between proactive or reactive aggression and cortisol secretion, or between any of the social-information processing variables and cortisol secretion. Predicted associations between proactive and reactive aggression and social-information processing variables were found. Overall, therefore, the mediational model was not supported. However, cortisol secretion was found to be associated with both anxiety and depression, and exploratory analyses revealed significant associations between cortisol secretion and Psychopathy as measured by the APSD. Taken together, the findings suggest that while the specific relationship proposed here among social-cognitive, psychophysiological, and behavioral variables was not found, an integrative model examining each of these components may be useful in further investigations of the complex phenomenon of childhood aggression. / Ph. D.

Made available in DSpace on 2015-07-22T20:49:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-29. Added 1 bitstream(s) on 2015-08-11T03:26:28Z : No. of bitstreams: 1 Publico-345.pdf: 1277830 bytes, checksum: 6d2949e2d33e045cfec88a295d473e41 (MD5) / Associação Fundo de Incentivo à Psicofarmacologia (AFIP) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Alguns estudos pré-clínicos têm demostrado que eventos adversos na infância e adolescência representam um fator de vulnerabilidade para o surgimento de transtornos psiquiátricos na idade adulta, e que a redução da resiliência à eventos estressantes deve desempenhar um papel importante neste fenômeno. As manipulações em animais de laboratório, como a privação materna (PM) por 24 h durante o período de hiporresposividade ao estresse (PHRE), podem ser um instrumento útil para a compreensão de como os eventos no período precoce do desenvolvimento resultam em alterações comportamentais e da atividade do eixo Hipotálamo-Pituitária-Adrenal (HPA) na idade adulta. Alguns autores têm observado que a PM, quando imposta no 3° dia de vida (antes do início) ou no 11° dia (no vale) do PHRE, resulta em padrões de atividade do eixo HPA distintos. A PM no 3° dia induz à hiperatividade do eixo, enquanto que no 11° dia, resulta na hipoatividade, alterações estas observadas em animais jovens. Assim, os principais objetivos do presente trabalho foram os de estudar como a PM afetaria a atividade do eixo HPA durante o PHRE, e verificar se essas alterações teriam conseqüências duradouras. Os resultados mostraram que os efeitos da PM na liberação de ACTH mantiveram o mesmo padrão de atividade relatado na adolescência, ou seja, hiperresponsividade no grupo submetido à PM no 3o dia de vida e hiporresponsividade no grupo submetido à mesma manipulação no 11o dia de vida. No entanto, essa alteração não se refletiu na liberação da corticosterona (CORT), pois não se observou diferença na secreção deste hormônio entre os grupos. Além disso, a PM não alterou a liberação de CORT em resposta ao Teste de supressão à Dexametasona, indicando que não houve alterações no sistema de retroalimentação negativa no nível hipofisário do eixo HPA. A PM afetou o comportamento do tipo ansioso nos animais de ambos os grupos PM, sendo que tal alteração parece não ter sido mediada por mudanças na densidade do sítio benzodiazepínico do receptor GABAA. Os resultados indicaram que, embora a PM não leve a alterações permanentes na secreção da corticosterona, este pode ser um modelo animal interessante para se estudar o substrato neurobiológico que faz com que um evento adverso durante o desenvolvimento aumente a vulnerabilidade aos transtornos relacionados à ansiedade. / Adverse events in childhood have been associated to the development of psychopathologies, such as depression and anxiety disorders. In rats, stressful events during neonatal period, like 24h Maternal Deprivation (MD), may be an interesting tool to understand how stress during early life leads to changes in behavior and stress response in adulthood. According to some studies, MD on the 3rd day (MD 3-4) or 11th day (MD 11- 12) of life results in opposite changes in the activity of the Hypothalamus-Pituitary- Adrenal (HPA) axis, i.e., hyper and hyporresponsiveness, respectively. Since in human beings psychopathologies has been related to impairment in resilience to stress the aim of this work was to investigate whether MD leads to long lasting changes in HPA axis functioning and differential behavioral features in animal models of anxiety. The results obtained indicate that only the ACTH release presented the pattern we hypothesized. Conversely the corticosterone (CORT) plasmatic levels do not reflect this pattern. Moreover, MD did not affect the CORT release in response to the Dexamethasone Suppression Test, indicating that there are MD did not alter the negative feedback system. Although MD did not lead to convincing alteration to CORT levels it did change anxiety-like behavior in the group MD 11-12. However this behavioral change did not seem to be mediated by expression of benzodiazepine site in GABAA receptors. The results indicate that even though the MD procedure does not lead to consistent changes in the peripheral component of the HPA axis it could still be an interesting animal model to study the neurobiological underpinnings of how adverse events in early life increase the vulnerability to psychopathologies. / FAPESP: 2006/06415-4 / TEDE / BV UNIFESP: Teses e dissertações

Mental toughness has received extensive research attention in recent years because of its intuitive and theoretical association with successful performance. However, several significant omissions in understanding remained. This thesis aimed to address these gaps through various research approaches and methodologies, collectively resulting in a biopsychological perspective. The primary objectives were to provide a more holistic perspective of mental toughness and generate quantitative support for the various biological (2D:4D) cognitive-affective (self-structure), physiological (cortisol response) and behavioural (performance) differences that have been associated with the construct. The findings suggested that mental toughness is a multifaceted construct and manifests in several areas of human functioning; specifically, a particular cognitive-affective profile may underlie mental toughness (they possess a positive self-concept and a particular self-structuring style, namely integration). Furthermore, levels of cortisol during a competitive event (a physiological indicator of perceived stress levels) were significantly negatively related to mental toughness, suggesting that mentally tough individuals have a reduced perception of threat in competitive situations (giving support for the notion that they perceive competition or stress as a potential challenge for personal growth and improvement). An objective marker of mental toughness was also supported; specifically, 2D:4D ratio (indicative of prenatal testosterone levels) related significantly with scores on a mental toughness scale, giving support for the biological underpinning of the construct and an objective marker of mental toughness. Finally, two case examples are provided to demonstrate the usability of these important markers (cognitive, biological and physiological) in an applied context.

The Hypothalamus-Pituitary-Adrenal axis (HPA-axis) with its end product cortisol mediates the physiological response to stress thereby promoting mobilization of energy. The cortisol levels follow a diurnal rhythm with a distinct awakening response. Regulation of the HPA-axis differs among persons with certain psychiatric disorders when compared with controls. Some reports concern Attention-Deficit/Hyperactivity Disorder (ADHD) but findings are inconclusive. The main aim of the present thesis was to investigate diurnal levels of saliva cortisol in school aged children with ADHD and age matched non-affected comparisons, also taking early adversity, perceived stress and ADHD-medication into consideration. Children with ADHD had lower cortisol levels at awakening, 30 minutes later and before going to bed than comparisons. When the study group was split into three different age groups similar results were found only for children above 10 years of age. Within the ADHD group, subtype of ADHD or co-occurring symptoms did not affect the cortisol levels. Furthermore, children in the ADHD group had to a higher degree been exposed to foetal and childhood psychosocial adversity than comparisons. Since exposure to early adversity has been associated with both ADHD and HPA-axis functioning, such exposures could theoretically explain the low cortisol levels in ADHD via early programming of the HPA-axis. However, no relation was found between exposures to psychosocial adversity and diurnal cortisol levels. Neither did continuous medication with stimulants or atomoxetine explain the low cortisol levels. Possibly, medication may rather increase the levels. Finally, children with ADHD scored higher on perceived stress, measured by the Pressure-Activation-Stress (PAS) scale, than the comparison group. Female sex was also associated with higher stress in both groups, as well as increasing age in the comparison group. As with psychosocial adversity, no association was found between the higher PAS-scores and the lower cortisol levels, indicating the complexity of the stress regulating system. The results indicate a down-regulated or displaced HPA-axis with lower cortisol levels in children with ADHD. Stress related fragility – with more exposure to early stressors, higher perceived stress and lower diurnal cortisol levels – seem to accompany ADHD during childhood.