Article

Stress signalling pathways that impair prefrontal cortex structure and function.

Department of Neurobiology, Yale University School of Medicine, New Haven, Connecticut 06510, USA.
Nature Reviews Neuroscience (Impact Factor: 31.38). 07/2009; 10(6):410-22. DOI: 10.1038/nrn2648
Source: PubMed

ABSTRACT The prefrontal cortex (PFC) - the most evolved brain region - subserves our highest-order cognitive abilities. However, it is also the brain region that is most sensitive to the detrimental effects of stress exposure. Even quite mild acute uncontrollable stress can cause a rapid and dramatic loss of prefrontal cognitive abilities, and more prolonged stress exposure causes architectural changes in prefrontal dendrites. Recent research has begun to reveal the intracellular signalling pathways that mediate the effects of stress on the PFC. This research has provided clues as to why genetic or environmental insults that disinhibit stress signalling pathways can lead to symptoms of profound prefrontal cortical dysfunction in mental illness.

4 Followers
 · 
150 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Hormones have nuanced effects on learning and memory processes. The degree and direction of the effect (e.g., is memory impaired or enhanced?) depends on the dose, type and stage of memory, and type of material being learned, among other factors. This review will focus on two specific topics within the realm of effects of hormones on memory: (1) How glucocorticoids (the output hormones of the hypothalamic-pituitary-adrenal axis) affect long-term memory consolidation, retrieval, and working memory, with a focus on neural mechanisms and effects of emotion; and (2) How oxytocin affects memory, with emphasis on a speculative hypothesis that oxytocin might exert its myriad effects on human social cognition and behavior via impacts on more general cognitive processes. Oxytocin-glucocorticoid interactions will be briefly addressed. These effects of hormones on memory will also be considered from an evolutionary perspective.
    06/2015; 1(2). DOI:10.1007/s40750-014-0010-4
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: While substantial scholarly attention has been paid to the beneficial consequences of transformational leadership and the conditions in which this leadership style is most effective, there is a remarkable shortage of research on the contextual antecedents of transformational leadership behavior itself. To address this gap, a laboratory experiment was conducted in which we tested the relationship between task complexity and the emergence of transformational leadership behavior. In this experiment, 111 participants were divided in groups of three (comprising one leader and two subordinates), and were instructed to solve three decision-making tasks with varying levels of task complexity. Results indicated that task complexity was negatively related to transformational leadership behavior, and that this relationship was partially mediated by the leader’s state core self-evaluations. In other words, when leaders encounter tasks that are overwhelmingly complex, they act in less transformational ways because they momentarily lack the psychological resources to do so. Limitations and future research directions are discussed.
    The Leadership Quarterly 04/2015; DOI:10.1016/j.leaqua.2015.02.008 · 2.70 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Stress-especially chronic, uncontrollable stress-is an important risk factor for many neuropsychiatric disorders. The underlying mechanisms are complex and multifactorial, but they involve correlated changes in structural and functional measures of neuronal connectivity within cortical microcircuits and across neuroanatomically distributed brain networks. Here, we review evidence from animal models and human neuroimaging studies implicating stress-associated changes in functional connectivity in the pathogenesis of PTSD, depression, and other neuropsychiatric conditions. Changes in fMRI measures of corticocortical connectivity across distributed networks may be caused by specific structural alterations that have been observed in the prefrontal cortex, hippocampus, and other vulnerable brain regions. These effects are mediated in part by glucocorticoids, which are released from the adrenal gland in response to a stressor and also oscillate in synchrony with diurnal rhythms. Recent work indicates that circadian glucocorticoid oscillations act to balance synapse formation and pruning after learning and during development, and chronic stress disrupts this balance. We conclude by considering how disrupted glucocorticoid oscillations may contribute to the pathophysiology of depression and PTSD in vulnerable individuals, and how circadian rhythm disturbances may affect non-psychiatric populations, including frequent travelers, shift workers, and patients undergoing treatment for autoimmune disorders.
    01/2015; 1:174-183. DOI:10.1016/j.ynstr.2014.10.008

Preview

Download
4 Downloads
Available from