The Omnipresence of Autonomic Modulation in Health and Disease

The Autonomic Nervous System (ANS) is a critical part of the homeostatic machinery with both central and peripheral components. However, little is known about the integration of these components and their joint role in the maintenance of health and in allostatic derailments leading to somatic and/or neuropsychiatric (co)morbidity. Based on a comprehensive literature search on the ANS neuroanatomy we dissect the complex integration of the ANS: (1) First we summarize Stress and Homeostatic Equilibrium - elucidating the responsivity of the ANS to stressors; (2) Second we describe the overall process of how the ANS is involved in Adaptation and Maladaptation to Stress; (3) In the third section the ANS is hierarchically partitioned into the peripheral/spinal, brainstem, subcortical and cortical components of the nervous system. We utilize this anatomical basis to define a model of autonomic integration. (4) Finally, we deploy the model to describe human ANS involvement in (a) Hypofunctional and (b) Hyperfunctional states providing examples in the healthy state and in clinical conditions.

Age effects on basic symptoms in the community: A route to gain new insight into the neurodevelopment of psychosis?

Reports of limited clinical significance of attenuated psychotic symptoms before age 15/16 indicate an important role of neurodevelopment in the early detection of psychoses. Therefore, we examined if age also exerts an influence on the prevalence and clinical significance of the 14 cognitive and perceptive basic symptoms (BS) used in psychosis-risk criteria and conceptualized as the most direct self-experienced expression of neurobiological aberrations. A random representative general population sample of the Swiss canton Bern (N = 689, age 8-40 years, 06/2011-05/2014) was interviewed for BS, psychosocial functioning, and current mental disorder. BS were reported by 18% of participants, mainly cognitive BS (15%). In regression analyses, age affected perceptive and cognitive BS differently, indicating an age threshold for perceptive BS in late adolescence (around age 18) and for cognitive BS in young adulthood (early twenties)-with higher prevalence, but a lesser association with functional deficits and the presence of mental disorder in the below-threshold groups. Thereby, interaction effects between age and BS on functioning and mental disorder were commonly stronger than individual effects of age and BS. Indicating support of the proposed "substrate-closeness" of BS, differential age effects of perceptual and cognitive BS seem to follow normal brain maturation processes, in which they might occur as infrequent and temporary non-pathological disturbances. Their persistence or occurrence after conclusion of main brain maturation processes, however, might signify aberrant maturation or neurodegenerative processes. Thus, BS might provide important insight into the pathogenesis of psychosis and into differential neuroprotective or anti-inflammatory targets.

Temporal control of glucocorticoid neurodynamics and its relevance for brain homeostasis, neuropathology and glucocorticoid-based therapeutics

Glucocorticoids mediate plethora of actions throughout the human body. Within the brain, they modulate aspects of immune system and neuroinflammatory processes, interfere with cellular metabolism and viability, interact with systems of neurotransmission and regulate neural rhythms. The influence of glucocorticoids on memory and emotional behaviour is well known and there is increasing evidence for their involvement in many neuropsychiatric pathologies. These effects, which at times can be in opposing directions, depend not only on the concentration of glucocorticoids but also the duration of their presence, the temporal relationship between their fluctuations, the co-influence of other stimuli, and the overall state of brain activity. Moreover, they are region- and cell type-specific. The molecular basis of such diversity of effects lies on the orchestration of the spatiotemporal interplay between glucocorticoid- and mineralocorticoid receptors, and is achieved through complex dynamics, mainly mediated via the circadian and ultradian pattern of glucocorticoid secretion. More sophisticated methodologies are therefore required to better approach the study of these hormones and improve the effectiveness of glucocorticoid-based therapeutics.