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
Social anxiety disorder (SAD) is the extreme fear and avoidance of one or more social situations. The goal of the current study was to investigate whether heart rate variability (HRV) during... Show moreSocial anxiety disorder (SAD) is the extreme fear and avoidance of one or more social situations. The goal of the current study was to investigate whether heart rate variability (HRV) during resting state and a social performance task (SPT) is a candidate endophenotype of SAD. In this two-generation family study, patients with SAD with their partner and children, and their siblings with partner and children took part in a SPT (total n = 121, 9 families, 3-30 persons per family, age range: 8-61 years, 17 patients with SAD). In this task, participants had to watch and evaluate the speech of a female peer, and had to give a similar speech. HRV was measured during two resting state phases, and during anticipation, speech and recovery phases of the SPT. We tested two criteria for endophenotypes: co-segregation with SAD within families and heritability. HRV did not co-segregate with SAD within families. Root mean square of successive differences during the first resting phase and recovery, and high frequency power during all phases of the task were heritable. It should be noted that few participants were diagnosed with SAD. Results during the speech should be interpreted with caution, because the duration was short and there was a lot of movement. HRV during resting state and the SPT is a possible endophenotype, but not of SAD. As other studies have shown that HRV is related to different internalizing disorders, HRV might reflect a transdiagnostic genetic vulnerability for internalizing disorders. Future research should investigate which factors influence the development of psychopathology in persons with decreased HRV. Show less
With this thesis the PhD-candidate aims to enrich the body of evidence concerning the relation between stress and health, and the mediating role of (un)conscious perseverative cognitions (which is... Show moreWith this thesis the PhD-candidate aims to enrich the body of evidence concerning the relation between stress and health, and the mediating role of (un)conscious perseverative cognitions (which is captured in the extended perseverative cognition hypothesis). The main aim of this thesis was to find direct evidence for the extended PC hypothesis in real life. She examined whether reducing (un)conscious perseverative cognitions, or worry, improved stress-related physiological activity and subjective health complaints. Show less
The goal of this dissertation was to delineate psychophysiological endophenotypes of social anxiety disorder. We conducted a unique two-generation family study, including patients with social... Show moreThe goal of this dissertation was to delineate psychophysiological endophenotypes of social anxiety disorder. We conducted a unique two-generation family study, including patients with social anxiety disorder, their partner and children, and their siblings with partner and children. This dissertation focused on EEG and heart rate measures during resting state, a social performance task and a social judgment paradigm. In the social performance task, participants watched and evaluated a speech of a female peer and then gave a speech in front of a video camera themselves. In the social judgment paradigm, participants received social acceptance or rejection feedback, after indicating their expectations about the upcoming feedback. This dissertation focused on three criteria for endophenotypes: association with SAD, co-segregation with SAD within families, and heritability. Delta-beta correlation during anticipation of a stressful social situation, and N1 and P3 amplitude in the social judgment paradigm are candidate endophenotypes of SAD. Show less
Long-term stability of individual differences in stress responses has repeatedly been demonstrated in adults, but few studies have investigated the development of stability in adolescence. The... Show moreLong-term stability of individual differences in stress responses has repeatedly been demonstrated in adults, but few studies have investigated the development of stability in adolescence. The present study was the first to investigate the stability of individual differences in heart rate, parasympathetic (RMSSD, pNN50, HF), sympathetic (LF/HF, SC), and HPA-axis (salivary cortisol) responses in a youth sample (8–19 years). Responses to public speaking were measured twice over 2 years. Stability was moderate for absolute responses and task delta responses of HR, RMSSD, pNN50, and HF. Stability was lower for SC and task delta responses of LF/HF and cortisol. Anticipation delta responses showed low stability for HR and cortisol. The latter was moderated by age or puberty, so that individual differences were more stable in more mature individuals. The results support the suggestion that stress responses may be reset during adolescence, but only for the HPA axis. Show less
Koopman Jacob J.E.; Bodegom David van; Maan Arie C.; Li Zhao; Ziem Juventus B.; Westendorp Rudi G.J.; Jukema J.Wouter 2015
A high heart rate and a low heart rate variability at rest are established predictors of various forms of functional impairment, morbidity, and mortality [1–6]. Two explanations can be given for... Show moreA high heart rate and a low heart rate variability at rest are established predictors of various forms of functional impairment, morbidity, and mortality [1–6]. Two explanations can be given for these associations. On one hand, a high heart rate and a low heart rate variability are thought to reflect dysfunction of the flexible autonomic regulation of the heart rate in particular and of the body's functioning in general that arises during ageing [3–5]. On the other hand, a high heart rate and a low heart rate variability are brought about by cardiovascular risk factors, such as obesity, hyperlipidaemia, diabetes, hypertension, and physical inactivity [2,3,7–9]. Since research on heart rate and heart rate variability has almost exclusively been conducted in western populations with an affluent sedentary lifestyle and high prevalences of these risk factors, it has been difficult to determine whether or not heart rate and heart rate variability are associated with functional impairment, morbidity, and mortality independently of cardiovascular risk factors. Show less
Berkelaar, M.; Eekhoff, E.M.W.; Simonis-Bik, A.M.C.; Boomsma, D.I.; Diamant, M.; Ijzerman, R.G.; ... ; Geus, E.J.C. de 2013