This book contains two main messages. First, an attempt is made to explain the diverse beneficial findings on cognition and mental health in the literature of meditation practices by the factor of... Show moreThis book contains two main messages. First, an attempt is made to explain the diverse beneficial findings on cognition and mental health in the literature of meditation practices by the factor of breathing. In the respiratory vagal nerve stimulation model of contemplative practices (rVNS) specific respiratory patterns lead to changes in autonomic nervous system functioning that in turn produce changes in the central nervous system, which can be observed in a healthier cognitive and emotional balance. Second, there are two empirical chapters that show null-results on cognition with meditative movement (Tai Chi Chuan) and breathing interventions. The possible reasons for these lack of results are extensively discussed in this dissertation and put into a wider perspective within the scientific field. Show less
ObjectiveRecently, salivary alpha-amylase (sAA) has been proposed as a suitable index for sympathetic activity and dysregulation of the autonomic nervous system (ANS). Although determinants of sAA... Show moreObjectiveRecently, salivary alpha-amylase (sAA) has been proposed as a suitable index for sympathetic activity and dysregulation of the autonomic nervous system (ANS). Although determinants of sAA have been described, they have not been studied within the same study with a large sample size without potential disturbances of psychopathology. In this paper, we report about correlates of evening sAA in saliva. MethodsIn 487 participants (mean age=42.9years, 59.8% female) without lifetime psychiatric disorders from the Netherlands Study of Depression and Anxiety (NESDA), sociodemographic, health and sampling determinants of sAA levels were examined using multivariable linear regression analysis. sAA was measured in two saliva samples that participants collected in the late evening, at 22:00h and 23:00h, after which these were averaged. ResultsIn multivariate analysis, age (β=0.20, p<0.001) and daily alcohol intake (β=−0.13, p=0.01) were independent determinants of evening sAA levels. Gender, allergy or lung disease, and the use of oral contraceptives were univariate correlates, but no longer associated with sAA in the multivariate model. ConclusionsAge and alcohol use were identified as potential confounding factors that should be taken into account in epidemiologic studies that examine the ANS function using sAA. Show less
