Publications by authors named "Karl-Jürgen Bär"

159 Publications

Conditioned Pain Modulation (CPM) Effects Captured in Facial Expressions.

J Pain Res 2021 23;14:793-803. Epub 2021 Mar 23.

Physiological Psychology, Otto-Friedrich University Bamberg, Bamberg, Germany.

Purpose: Conditioned pain modulation (CPM) is most often assessed using self-report of pain. However, self-report of pain is not always available (eg in individuals with cognitive impairment) and is susceptible to report bias. In comparison, the facial expression of pain is more reflex-like and represents one of the most sensitive and specific non-verbal signals of pain. The aim of the present study was to investigate whether the facial expression of pain is sensitive enough to capture endogenous pain inhibition as elicited during CPM paradigms.

Patients And Methods: In total, 26 female participants took part in this study. Facial and verbal responses to phasic heat pain were assessed once while participants immersed their hand in a hot water bath and once without additional stimulation. Facial responses were analyzed using the Facial Action Coding System (FACS). Verbal responses were assessed using a Numerical Rating Scale (NRS).

Results: Pain-relevant facial responses as well as pain ratings to phasic heat pain were significantly reduced when participants simultaneously immersed their hand in a hot water bath compared to baseline. Thus, CPM effects could be demonstrated both on subjective as well as on facial responses. Moreover, CPM-induced changes in pain-relevant facial responses and in NRS ratings were significantly correlated.

Conclusion: The present study shows that facial expressions of pain are sensitive enough to capture CPM effects. Given the proven clinical usefulness of assessing CPM, the parallel assessment of verbal and facial CPM effects might be a promising approach with wider scope of applications. Further research in other demographic healthy participant and clinical cohorts is warranted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/JPR.S300313DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8001584PMC
March 2021

Working memory in schizophrenia: The role of the locus coeruleus and its relation to functional brain networks.

Brain Behav 2021 Mar 30:e02130. Epub 2021 Mar 30.

Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC), Department of Psychosomatic Medicine and Psychotherapy, University Hospital Jena, Germany.

Evidence suggests functional brain networks, especially the executive control network (ECN) and default mode network (DMN), to be abnormal in schizophrenia. Dysfunctions within the locus coeruleus (LC)-noradrenaline (NE) system, which is supposed to be pivotal to modulate neuronal network activation during executive control (e.g., working memory function), are also considered to play a vital role in the occurrence of positive (e.g., hallucinatory) or negative (e.g., inattentive) symptoms in these patients. In the present study, we sought to shed further light on the role of the LC-NE system in patients with schizophrenia. More specifically, we wanted to improve our understanding of the relationship and possible disturbances of the ECN and DMN during a working memory task in patients. A total of 58 healthy control subjects and 40 medicated patients with schizophrenia were investigated using a working memory 3-back task during functional magnetic resonance imaging. Main findings of our present study were differential dynamics of ECN and DMN blood oxygenation level-dependent (BOLD) activations with increasing task demands in both patients and controls. Moreover, we found increased BOLD activation in the LC in patients compared to controls in the interaction contrast between groups and conditions. LC BOLD activation significantly correlated with both, the main hub of the ECN, that is, the dorsolateral prefrontal cortex, and of the DMN, that is, the posterior cingulate cortex. Thus, the LC-NE system seems to be crucial in modulating neuronal network activity in a 3-back working memory task and might significantly contribute to cognitive impairments in schizophrenia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/brb3.2130DOI Listing
March 2021

Cortical thinning and associated connectivity changes in patients with anorexia nervosa.

Transl Psychiatry 2021 Feb 4;11(1):95. Epub 2021 Feb 4.

Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC), Department of Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Jena, Germany.

Structural brain abnormalities are a consistent finding in anorexia nervosa (AN) and proposed as a state biomarker of the disorder. Yet little is known about how regional structural changes affect intrinsic resting-state functional brain connectivity (rsFC). Using a cross-sectional, multimodal imaging approach, we investigated the association between regional cortical thickness abnormalities and rsFC in AN. Twenty-two acute AN patients and twenty-six age- and gender-matched healthy controls underwent a resting-state functional magnetic resonance imaging scan and cognitive tests. We performed group comparisons of whole-brain cortical thickness, seed-based rsFC, and network-based statistical (NBS) analyses. AN patients showed cortical thinning in the precuneus and inferior parietal lobules, regions involved in visuospatial memory and imagery. Cortical thickness in the precuneus correlated with nutritional state and cognitive functions in AN, strengthening the evidence for a critical role of this region in the disorder. Cortical thinning was accompanied by functional connectivity reductions in major brain networks, namely default mode, sensorimotor and visual networks. Similar to the seed-based approach, the NBS analysis revealed a single network of reduced functional connectivity in patients, comprising mainly sensorimotor- occipital regions. Our findings provide evidence that structural and functional brain abnormalities in AN are confined to specific regions and networks involved in visuospatial and somatosensory processing. We show that structural changes of the precuneus are linked to nutritional and functional states in AN, and future longitudinal research should assess how precuneus changes might be related to the evolution of the disorder.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41398-021-01237-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7862305PMC
February 2021

Cortical thinning and associated connectivity changes in patients with anorexia nervosa.

Transl Psychiatry 2021 Feb 4;11(1):95. Epub 2021 Feb 4.

Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC), Department of Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Jena, Germany.

Structural brain abnormalities are a consistent finding in anorexia nervosa (AN) and proposed as a state biomarker of the disorder. Yet little is known about how regional structural changes affect intrinsic resting-state functional brain connectivity (rsFC). Using a cross-sectional, multimodal imaging approach, we investigated the association between regional cortical thickness abnormalities and rsFC in AN. Twenty-two acute AN patients and twenty-six age- and gender-matched healthy controls underwent a resting-state functional magnetic resonance imaging scan and cognitive tests. We performed group comparisons of whole-brain cortical thickness, seed-based rsFC, and network-based statistical (NBS) analyses. AN patients showed cortical thinning in the precuneus and inferior parietal lobules, regions involved in visuospatial memory and imagery. Cortical thickness in the precuneus correlated with nutritional state and cognitive functions in AN, strengthening the evidence for a critical role of this region in the disorder. Cortical thinning was accompanied by functional connectivity reductions in major brain networks, namely default mode, sensorimotor and visual networks. Similar to the seed-based approach, the NBS analysis revealed a single network of reduced functional connectivity in patients, comprising mainly sensorimotor- occipital regions. Our findings provide evidence that structural and functional brain abnormalities in AN are confined to specific regions and networks involved in visuospatial and somatosensory processing. We show that structural changes of the precuneus are linked to nutritional and functional states in AN, and future longitudinal research should assess how precuneus changes might be related to the evolution of the disorder.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41398-021-01237-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7862305PMC
February 2021

A common variation in HCN1 is associated with heart rate variability in schizophrenia.

Schizophr Res 2020 Nov 18. Epub 2020 Nov 18.

Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC), Department of Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Jena, Germany. Electronic address:

Background: There is growing evidence for a shared genetic basis between schizophrenia risk and cardiovascular disease. Reduced efferent vagal activity, indexed by reduced heart rate variability (HRV), has been consistently described in patients with schizophrenia and may potentially contribute to the increased cardiovascular risk in these patients. In this study, we tested the hypothesis whether the established schizophrenia risk variant HCN1 rs16902086 (A > G) is associated with reduced HRV.

Methods: We analyzed the risk status of HCN1 rs16902086 (AG/GG vs. AA genotype) in 83 unmedicated patients with schizophrenia and 96 healthy controls and investigated genotype-related impacts on various HRV parameters.

Results: We observed significantly increased resting heart rates and a marked decrease of vagal modulation in our patient cohort. Strikingly, HCN1 rs16902086 (A > G) was associated with reduced HRV parameters in patients only. A trend towards more pronounced HRV deviations was observed in homozygous (GG) compared to heterozygous patients (AG).

Conclusion: We present first evidence for a genetic risk factor that is associated with decreased vagal modulation in unmedicated patients with schizophrenia. Moreover, our findings suggest that HCN1 might be involved in reduced vagal modulation and possibly in increased cardiac mortality in schizophrenia patients. Thus, our data indicate that reduced vagal modulation might be an endophenotype of schizophrenia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.schres.2020.11.017DOI Listing
November 2020

Microstructural alterations in medial forebrain bundle are associated with interindividual pain sensitivity.

Hum Brain Mapp 2021 Mar 10;42(4):1130-1137. Epub 2020 Nov 10.

Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, and Harvard Medical School, Boston, Massachusetts, USA.

The perception of pain to noxious stimuli, also known as pain sensitivity, varies among individuals. The comprised brain structures and their white matter pathways are complex and elusive. Here, we aimed to investigate whether variation of microstructure of the medial forebrain bundle (MFB), a tract connecting the basal forebrain with the brain stem, is associated with interindividual pain sensitivity. We assessed interindividual pain sensitivity as a rating of pain intensity to heat stimuli (45, 47, and 48.9°C) in 38 healthy men (age: 27.05 ± 5.7 years). We also reconstructed the MFB using multitensor tractography from diffusion magnetic resonance imaging (dMRI) and calculated free-water corrected dMRI measures of fractional anisotropy (FA ), radial diffusivity (RD ), and axial diffusivity (AD ). Lower ratings of interindividual pain intensity correlated with higher FA and lower RD of the MFB. As changes in FA and RD may reflect abnormalities in myelination, the results might be interpreted as that a lower pain rating is associated with higher degree of myelination of the MFB and could represent an inhibitory pathway of pain. Our results suggest that alteration of microstructure in the MFB contributes to the interindividual variation of pain perception.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/hbm.25281DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7856635PMC
March 2021

Interrelations between dopamine and serotonin producing sites and regions of the default mode network.

Hum Brain Mapp 2021 Feb 31;42(3):811-823. Epub 2020 Oct 31.

Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC), Department of Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Germany.

Recent functional magnetic resonance imaging (fMRI) studies showed that blood oxygenation level-dependent (BOLD) signal fluctuations in the default mode network (DMN) are functionally tightly connected to those in monoaminergic nuclei, producing dopamine (DA), and serotonin (5-HT) transmitters, in the midbrain/brainstem. We combined accelerated fMRI acquisition with spectral Granger causality and coherence analysis to investigate causal relationships between these areas. Both methods independently lead to similar results and confirm the existence of a top-down information flow in the resting-state condition, where activity in core DMN areas influences activity in the neuromodulatory centers producing DA/5-HT. We found that latencies range from milliseconds to seconds with high inter-subject variability, likely attributable to the resting condition. Our novel findings provide new insights into the functional organization of the human brain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/hbm.25264DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7814772PMC
February 2021

Dissociation of Endogenous Pain Inhibition Due to Conditioned Pain Modulation and Placebo in Male Athletes Versus Nonathletes.

Front Psychol 2020 18;11:553530. Epub 2020 Sep 18.

Department of Clinical Psychology, Friedrich-Schiller-University Jena, Jena, Germany.

Animals and humans are able to inhibit pain by activating their endogenous pain-inhibition system. Endurance athletes possess a higher pain-tolerance threshold and a greater conditioned pain modulation (CPM) effect than nonathletes, suggesting better endogenous pain inhibition. In addition to CPM, placebo is another prominent paradigm used to test endogenous pain inhibition. However, whether the placebo effect and the CPM effect share the same mechanisms of pain inhibition has not been investigated. If there is a shared mechanism, then endurance athletes should show not only a better CPM effect than nonathletes but also a greater placebo effect. Here, we investigated 16 male endurance athletes and 17 male nonathletes in well-established placebo and CPM paradigms to assess whether endurance athletes have a better endogenous pain-inhibition system than nonathletes. As expected, we find a significantly greater CPM effect in athletes than in nonathletes. In contrast, we could only find a significant placebo effect in nonathletes. Explorative analyses reveal negative associations between the placebo effect and heart rate variability as well as between the placebo effect and interoceptive awareness. Together, the results demonstrate a dissociation of endogenous pain inhibition of CPM and placebo effect between endurance athletes and nonathletes. This suggests that both effects are based, at least in part, on different biological mechanisms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fpsyg.2020.553530DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7531190PMC
September 2020

Cortical thickness and resting-state cardiac function across the lifespan: A cross-sectional pooled mega-analysis.

Psychophysiology 2020 Oct 10. Epub 2020 Oct 10.

Norwegian Centre for Mental Disorders Research (NORMENT), Institute of Clinical Medicine, University of Oslo, Oslo, Norway.

Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting-state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega-analysis (N = 1,218 (50.5% female), mean age 36.7 years (range: 12-87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS-or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between CT and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/psyp.13688DOI Listing
October 2020

The Cardiorespiratory Network in Healthy First-Degree Relatives of Schizophrenic Patients.

Front Neurosci 2020 16;14:617. Epub 2020 Jun 16.

Institute of Innovative Health Technologies (IGHT), University of Applied Sciences, Jena, Germany.

Impaired heart rate- and respiratory regulatory processes as a sign of an autonomic dysfunction seems to be obviously present in patients suffering from schizophrenia. Since the linear and non-linear couplings within the cardiorespiratory system with respiration as an important homeostatic control mechanism are only partially investigated so far for those subjects, we aimed to characterize instantaneous cardiorespiratory couplings by quantifying the casual interaction between heart rate (HR) and respiration (RESP). Therefore, we investigated causal linear and non-linear cardiorespiratory couplings of 23 patients suffering from schizophrenia (SZO), 20 healthy first-degree relatives (REL) and 23 healthy subjects, who were age-gender matched (CON). From all participants' heart rate (HR) and respirations (respiratory frequency, RESP) were investigated for 30 min under resting conditions. The results revealed highly significant increased HR, reduced HR variability, increased respiration rates and impaired cardiorespiratory couplings in SZO in comparison to CON. SZO were revealed bidirectional couplings, with respiration as the driver (RESP → HR), and with weaker linear and non-linear coupling strengths when RESP influencing HR (RESP → HR) and with stronger linear and non-linear coupling strengths when HR influencing RESP (HR → RESP). For REL we found only significant increased HR and only slightly reduced cardiorespiratory couplings compared to CON. These findings clearly pointing to an underlying disease-inherent genetic component of the cardiac system for SZO and REL, and those respiratory alterations are only clearly present in SZO seem to be connected to their mental emotional states.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnins.2020.00617DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7308718PMC
June 2020

Sympathetic and Parasympathetic Modulation of Pupillary Unrest.

Front Neurosci 2020 11;14:178. Epub 2020 Mar 11.

Lab for Autonomic Neuroscience, Imaging and Cognition (LANIC), Department of Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Jena, Germany.

Pupillary unrest is an established indicator of drowsiness or sleepiness. How sympathetic and parasympathetic activity contribute to pupillary unrest is not entirely unclear. In this study, we investigated 83 young healthy volunteers to assess the relationship of pupillary unrest to other markers of the autonomic nervous system. Sample entropy (SE) and the established pupillary unrest index (PUI) were calculated to characterize pupil size variability. Autonomic indices were derived from heart rate, blood pressure, respiration, and skin conductance. Additionally, we assessed individual levels of calmness, vigilance, and mood. In an independent sample of 26 healthy participants, we stimulated the cardiovagal system by a deep breathing test. PUI was related to parasympathetic cardiac indices and sleepiness. A linear combination of vagal heart rate variability [root mean square of heart beat interval differences (RMSSD)] and skin conductance fluctuations (SCFs) was suited best to explain interindividual variance of PUI. Complexity of pupil diameter (PD) variations correlated to indices of sympathetic skin conductance. Furthermore, we found that spontaneous fluctuations of skin conductance are accompanied by increases of pupil size. In an independent sample, we were able to corroborate the relation of PUI with RMSSD and skin conductance. A slow breathing test enhanced RMSSD and PUI proportionally to each other, while complexity of PD dynamics decreased. Our data suggest that the slow PD oscillations ( < 0.15 Hz) quantified by PUI are related to the parasympathetic modulation. Sympathetic arousal as detected by SCFs is associated to transient pupil size increases that increase non-linear pupillary dynamics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnins.2020.00178DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7078331PMC
March 2020

Cardio-Respiratory Fitness and Autonomic Function in Patients with Major Depressive Disorder.

Front Psychiatry 2019 5;10:980. Epub 2020 Feb 5.

Psychiatric Brain and Body Research Group, Department of Psychosomatic Medicine, University Hospital, Jena, Germany.

Patients with major depressive disorder (MDD) have an augmented risk of cardiovascular morbidity and mortality. Although a link between depression and autonomic dysfunction as well as reduced cardio-respiratory fitness (CRF) is well documented, the underlying cause is a matter of debate. Therefore, we studied the interplay between autonomic function, body composition and severity of the disease to disentangle possible physiological factors influencing the assumed lack of CRF in MDD patients. We investigated seventeen patients suffering from MDD and seventeen control subjects matched with respect to age, sex, body-mass-index, and smoking habits. A resting baseline assessment and a cardiopulmonary exercise test including a prolonged recovery period were performed to study autonomic function (i.e., heart rate responses and heart rate variability) during rest, exercise and recovery as well as CRF. Most investigated autonomic indices were significantly different at rest, during exercise as well as during recovery indicating altered autonomic modulation. Nevertheless, none of our participants was classified as chronotropically incompetent. As expected, a reduced CRF (i.e., peak oxygen uptake and peak power output, p < 0.01) was observed in patients compared to controls. In addition, a correlation of baseline heart rate and of heart rate during recovery with the ventilatory threshold 1 (p < 0.05) was found in patients only, indicating a relation to the lack of CRF. Furthermore, we observed a positive correlation of the severity of the disease with the weekly sitting time (p < 0.01) as well as a negative correlation with the activity time in the intensity domain walking (p < 0.001) and with the total score of the International Physical Activity Questionnaire (p < 0.01) for patients. This study shows that patients with MDD have altered autonomic function not only during resting conditions but also during exercise as well as recovery from exercise. Intervention studies are needed to evaluate how the described autonomic alterations can be influenced by increasing CRF due to appropriate exercise training programs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fpsyt.2019.00980DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7011194PMC
February 2020

The relation of skin conductance and pupillary fluctuations assessed by phase-rectified signal averaging.

Annu Int Conf IEEE Eng Med Biol Soc 2019 Jul;2019:725-728

The reaction of pupil diameter and skin conductance are widely studied marker of the autonomic response to arousing stimuli. However, little is known about their relation at rest. In this study, we used bivariate phase-rectified signal averaging to investigate the relationship of skin conductance fluctuations (SCF) and pupillary fluctuations in 83 healthy volunteers. The onset of each SCF was detected by a pattern matching algorithm. Those time points were corrected for a different neurotransmission delay. Cross-correlation of temporal derivatives of pupil diameter and skin conductance revealed an average time lag of 2.5s. Thus, anchor points 2.5s before an SCF were defined. The pupillary signal following these anchors (7s) were extracted and normalized to baseline 1s prior to the anchor point. Aligned segments were averaged to determine the amplitude and area under the curve (AUC) of characteristic pupil diameter fluctuations (PDF) concurrent to SCF. The same procedure was applied to random time points (non-SCF) with at least 1s distance to actually detected SCF which served as control condition. SCF were accompanied by increases of pupil diameter with a maximum dilation of 9% on average. The one sample t-test indicated an AUC of PDF (70 ± 110 n.u., p<; 0.001). The maximum change and AUC of pupillary reactions were significantly higher when PDF extraction was triggered by actual SCF (both p<; 0.001). Both measures of pupillary dilations contributed significantly to pupillary unrest. Our results suggest that sympathetic arousal as detected by skin conductance fluctuations is accompanied by pupil dilation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/EMBC.2019.8857713DOI Listing
July 2019

Functional consequences of acute tryptophan depletion on raphe nuclei connectivity and network organization in healthy women.

Neuroimage 2020 02 16;207:116362. Epub 2019 Nov 16.

Psychiatric Brain and Body Research Group, Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany. Electronic address:

Previous research on central nervous serotonin (5-HT) function provided evidence for a substantial involvement of 5-HT in the regulation of brain circuitries associated with cognitive and affective processing. The underlying neural networks comprise core subcortical/cortical regions such as amygdala and medial prefrontal cortex, which are assumed to be modulated amongst others by 5-HT. Beside the use of antidepressants, acute tryptophan depletion (ATD) is a widely accepted technique to manipulate of 5-HT synthesis and its respective metabolites in humans by means of a dietary and non-pharmacological tool. We used a double-blind, randomized, cross-over design with two experimental challenge conditions, i.e. ATD and tryptophan (TRP) supplementation (TRYP+) serving as a control. The aim was to perturb 5-HT synthesis and to detect its impact on brain functional connectivity (FC) of the upper serotonergic raphe nuclei, the amygdala and the ventromedial prefrontal cortex as well as on network organization using resting state fMRI. 30 healthy adult female participants (age: M ​= ​24.5 ​± ​4.4 ​yrs) were included in the final analysis. ATD resulted in a 90% decrease of TRP in the serum relative to baseline. Compared to TRYP ​+ ​for the ATD condition a significantly lower FC of the raphe nucleus to the frontopolar cortex was detected, as well as greater functional coupling between the right amygdala and the ventromedial prefrontal cortex. FC of the raphe nucleus correlated significantly with the magnitude of TRP changes for both challenge conditions (ATD & TRYP+). Network-based statistical analysis using time series from 260 independent anatomical ROIs revealed significantly greater FC after ATD compared to TRYP+ in several brain regions being part of the default-mode (DMN) and the executive-control networks (ECN), but also of salience or visual networks. Finally, we observed an impact of ATD on the rich-club organization in terms of decreased rich-club coefficients compared to TRYP+. In summary we could confirm previous findings that the putative decrease in brain 5-HT synthesis via ATD significantly alters FC of the raphe nuclei as well as of specific subcortical/cortical regions involved in affective, but also in cognitive processes. Moreover, an ATD-effect on the so-called rich-club organization of some nodes with the high degree was demonstrated. This may indicate effects of brain 5-HT on the integration of information flow from several brain networks.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuroimage.2019.116362DOI Listing
February 2020

Functional consequences of acute tryptophan depletion on raphe nuclei connectivity and network organization in healthy women.

Neuroimage 2020 02 16;207:116362. Epub 2019 Nov 16.

Psychiatric Brain and Body Research Group, Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany. Electronic address:

Previous research on central nervous serotonin (5-HT) function provided evidence for a substantial involvement of 5-HT in the regulation of brain circuitries associated with cognitive and affective processing. The underlying neural networks comprise core subcortical/cortical regions such as amygdala and medial prefrontal cortex, which are assumed to be modulated amongst others by 5-HT. Beside the use of antidepressants, acute tryptophan depletion (ATD) is a widely accepted technique to manipulate of 5-HT synthesis and its respective metabolites in humans by means of a dietary and non-pharmacological tool. We used a double-blind, randomized, cross-over design with two experimental challenge conditions, i.e. ATD and tryptophan (TRP) supplementation (TRYP+) serving as a control. The aim was to perturb 5-HT synthesis and to detect its impact on brain functional connectivity (FC) of the upper serotonergic raphe nuclei, the amygdala and the ventromedial prefrontal cortex as well as on network organization using resting state fMRI. 30 healthy adult female participants (age: M ​= ​24.5 ​± ​4.4 ​yrs) were included in the final analysis. ATD resulted in a 90% decrease of TRP in the serum relative to baseline. Compared to TRYP ​+ ​for the ATD condition a significantly lower FC of the raphe nucleus to the frontopolar cortex was detected, as well as greater functional coupling between the right amygdala and the ventromedial prefrontal cortex. FC of the raphe nucleus correlated significantly with the magnitude of TRP changes for both challenge conditions (ATD & TRYP+). Network-based statistical analysis using time series from 260 independent anatomical ROIs revealed significantly greater FC after ATD compared to TRYP+ in several brain regions being part of the default-mode (DMN) and the executive-control networks (ECN), but also of salience or visual networks. Finally, we observed an impact of ATD on the rich-club organization in terms of decreased rich-club coefficients compared to TRYP+. In summary we could confirm previous findings that the putative decrease in brain 5-HT synthesis via ATD significantly alters FC of the raphe nuclei as well as of specific subcortical/cortical regions involved in affective, but also in cognitive processes. Moreover, an ATD-effect on the so-called rich-club organization of some nodes with the high degree was demonstrated. This may indicate effects of brain 5-HT on the integration of information flow from several brain networks.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuroimage.2019.116362DOI Listing
February 2020

[Implementation of exercise therapy in daily clinical practice in psychiatric clinics in Germany].

Nervenarzt 2020 Jul;91(7):642-650

Klinik für Psychiatrie und Psychotherapie, Campus Charité Mitte, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117, Berlin, Deutschland.

Exercise therapy has proven to be effective in the treatment of multiple mental illnesses. As mental disorders result in tremendous costs for the healthcare system as well as a huge burden for the affected individuals, improving treatment strategies according to latest scientific evidence should be of highest priority. In 2016 a first study provided indications that only a minority of patients are treated with exercise therapy during their stay in hospital. Hence, the aim of this study was to assess the actual extent of exercise therapy usage in psychiatric inpatients in Germany, thereby giving a scientific foundation to the call for a better standard of care. To achieve this, a retrospective analysis was performed on pre-existing data from 2693 patients who were treated in 1 of 4 participating university hospitals. Only 23% of these patients participated in exercise therapy with a mean training duration of 36 min per week. Patients with the diagnosis of schizophrenia or patients with multiple comorbidities were even less likely to participate in exercise therapy. With these findings it becomes evident that the healthcare situation concerning exercise therapy is insufficient. Solid evidence for the effectiveness of exercise therapy, the current treatment guidelines as well as the positive side effects, especially when compared to side effects of pharmacotherapy (i.e. weight gain) should motivate healthcare officials to make an effort to improve this situation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00115-019-0782-7DOI Listing
July 2020

Altered Causal Coupling Pathways within the Central-Autonomic-Network in Patients Suffering from Schizophrenia.

Entropy (Basel) 2019 Jul 26;21(8). Epub 2019 Jul 26.

Institute of Innovative Health Technologies, University of Applied Sciences, 07745 Jena, Germany.

The multivariate analysis of coupling pathways within physiological (sub)systems focusing on identifying healthy and diseased conditions. In this study, we investigated a part of the central-autonomic-network (CAN) in 17 patients suffering from schizophrenia (SZO) compared to 17 age-gender matched healthy controls (CON) applying linear and nonlinear causal coupling approaches (normalized short time partial directed coherence, multivariate transfer entropy). Therefore, from all subjects continuous heart rate (successive beat-to-beat intervals, BBI), synchronized maximum successive systolic blood pressure amplitudes (SYS), synchronized calibrated respiratory inductive plethysmography signal (respiratory frequency, RESP), and the power P of frontal EEG activity were investigated for 15 min under resting conditions. The CAN revealed a bidirectional coupling structure, with central driving towards blood pressure (SYS), and respiratory driving towards P. The central-cardiac, central-vascular, and central-respiratory couplings are more dominated by linear regulatory mechanisms than nonlinear ones. The CAN showed significantly weaker nonlinear central-cardiovascular and central-cardiorespiratory coupling pathways, and significantly stronger linear central influence on the vascular system, and on the other hand significantly stronger linear respiratory and cardiac influences on central activity in SZO compared to CON, and thus, providing better understanding of the interrelationship of central and autonomic regulatory mechanisms in schizophrenia might be useful as a biomarker of this disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/e21080733DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7515262PMC
July 2019

Effect of an eight-week smartphone-guided HRV-biofeedback intervention on autonomic function and impulsivity in healthy controls.

Physiol Meas 2019 07 1;40(6):064001. Epub 2019 Jul 1.

Psychiatric Brain and Body Research Group Jena, Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany.

A large body of scientific studies suggest a close relationship between increased vagal function and better cognitive performance.

Objective: In the current study, we investigated the association between autonomic function and behavioral impulsivity. We hypothesized that heart rate variability (HRV) biofeedback training increases HRV and enhances inhibitory control.

Approach: A total of 28 healthy participants were recruited. After drop-out, 14 participants completed an eight-week HRV biofeedback training with five training sessions per week including one session at the clinic's laboratory and four sessions at home using a mobile application running on their smartphone. Ten control subjects matched with respect to age and gender played a mobile game according to the same schedule as the biofeedback group. The assessment of autonomic status and the stop-signal task were conducted before the beginning of the training (T1) and after finishing the schedule (T2).

Main Results: We found a relationship of reaction times in the stop-signal task and standard HRV as well as cardiorespiratory indices. After biofeedback training, short-term HRV and baroreflex function significantly increased by 33% (CI [2%, 64%], p   <  0.05) and 21% (CI [5%, 36%], p   <  0.05), respectively. The performance in the stop-signal task was not affected by the biofeedback intervention. Compared to the changes of autonomic indices in the control group, only a decrease of skin conductance levels in the biofeedback group remained statistically significant.

Significance: Our results indicate that a smartphone-based HRV biofeedback intervention can be applied to improve cardiovagal function in healthy subjects. Although higher HRV was associated with higher levels of inhibitory control, HRV biofeedback had no effect on measures of impulsivity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1088/1361-6579/ab2065DOI Listing
July 2019

The relationship between heart rate and functional connectivity of brain regions involved in autonomic control.

Neuroimage 2019 08 11;196:318-328. Epub 2019 Apr 11.

Psychiatric Brain and Body Research Group, Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany. Electronic address:

The peripheral autonomic nervous system (ANS) adjusts the heart rate (HR) to intrinsic and extrinsic demands. It is controlled by a group of functionally connected brain regions assembling the so-called central autonomic network (CAN). More specifically, forebrain cortical regions, limbic and brainstem structures within the CAN have been identified as important components of circuits involved in HR regulation. The present study aimed to investigate whether functional connectivity (FC) between these regions varies in subjects with different heart rates. Thus, 84 healthy subjects were separated according to their HR in slow, medium and fast. We observed a direct association between HR and FC in CAN regions, where stronger FC was related to slower HR. This relationship, however, is non-linear, follows an exponential course and is not restricted to CAN areas only. The network-based analysis (NBS) using time series from 262 independent anatomical ROIs revealed significantly increased functional connectivity in subjects with slow HR compared to subjects with fast HR mainly in regions being part of the salience network, but also of the default-mode network. We additionally simulated the effect of aliasing on the functional connectivity using several TRs and heart rates to exclude the possibility that FC differences might be due to different aliasing effects in the data. The result of the simulation indicated that aliasing cannot explain our findings. Thus, present results imply a functionally meaningful coupling between FC and HR that need to be accounted for in future studies. Moreover, given the established link between HR and emotional, cognitive and social processes, present findings may also be considered to explain individual differences in brain activation or connectivity when using corresponding paradigms in the MR scanner to investigate such processes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuroimage.2019.04.014DOI Listing
August 2019

Checking and washing rituals are reflected in altered cortical thickness in obsessive-compulsive disorder.

Cortex 2019 08 26;117:147-156. Epub 2019 Mar 26.

Psychiatric Brain & Body Research Group Jena, Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany.

There is growing evidence for structural brain alterations in obsessive-compulsive disorder (OCD). The overall picture is however rather heterogeneous. To detect meaningful associations between clinical symptom profiles and structural alterations, we applied a classification approach, the k-means cluster analysis on clinical data, i.e., the Obsessive Compulsive Inventory-Revised (OCI-R) questionnaire. 73 OCD patients were assigned to three distinct symptom profiles. Using structural MRI and surface-based morphometric analysis (SBM), we compared cortical thickness between all OCD patients and 69 matched healthy subjects as well as among patients according to three symptom profiles. The total sample of OCD patients exhibited a thicker cortex in the pre-supplementary motor cortex (pre-SMA), dorsomedial prefrontal (DMPFC), anterior cingulate cortex and in the right anterior insula. Comparing patients of the three symptom clusters, a subgroup of OCD patients with a specific symptom profile was identified, which showed a thicker cortex in pre-SMA/DMPFC and in the contralateral primary motor cortex. In contrast to both other subgroups, patients in this group were mainly characterized by the predominance of a combination of checking and washing rituals. The other two OCD symptom subgroups showed comparable cortical thickness to healthy controls. Higher cortical thickness in regions of the motor circuitry seems to be related to motor activity-induced neuroplasticity in a specific group of OCD patients. Thicker anterior insular cortex in the total sample of patients points toward a more general pathophysiological process in OCD and potentially indicates abnormal interoceptive processing in OCD.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cortex.2019.03.012DOI Listing
August 2019

The Influence of Continuous Exercising on Chronotropic Incompetence in Multi-Episode Schizophrenia.

Front Psychiatry 2019 13;10:90. Epub 2019 Mar 13.

Psychiatric Brain and Body Research Group, Department of Psychiatry and Psychotherapy, University Hospital Jena, Jena, Germany.

People with schizophrenia die on average 15-20 years earlier than age and gender matched controls in the general population. An essential part of this excess mortality in people with schizophrenia is caused by physical illnesses. Among the physical illnesses, cardiovascular disease (CVD) has been identified as the most common natural cause of death in up to 40-45% of the cases. Chronotropic incompetence (CI) is defined as the inability of the heart to increase its beating frequency in proportion to increased physical activity or higher metabolic demand. It is an established independent cardiovascular risk factor for major cardiac events and overall mortality and might explain adaptation intolerance of the cardiovascular system to even minor exercise courses. CI needs objective exercise testing for definitive diagnosis and therefore represents a biological marker indicating the integrity of the cardiovascular system. It was recently described in patients with schizophrenia and might help explain the reduced physical fitness in these patients and the inability of a subgroup of patients to benefit from exercise interventions. In this study, we tried to replicate the occurrence of CI in an independent sample of patients with schizophrenia and evaluated whether CI can be influenced by a continuous endurance training of 12 weeks. Therefore, we re-analyzed the fitness testing data of 43 patients with schizophrenia and 22 aged and gender matched healthy controls. Parameters of aerobic fitness and chronotropic response to exercise were calculated. Patients with schizophrenia were less physically fit than the healthy controls and displayed a significantly higher heart rate at rest. 10 of 43 patients with schizophrenia and no healthy control subject were classified as chronotropically incompetent. Chronotropic response to exercise did not change significantly after 12 weeks of continuous aerobic exercise training. No differences were observed for baseline heart rate and peak heart rate in both subgroups of schizophrenia patients. Aerobic fitness did not improve significantly in the patients with schizophrenia classified as chronotropically incompetent. Our results confirm the occurrence of CI in patients with multi-episode schizophrenia. This should be taken into account when planning an exercise or lifestyle intervention studies in this population. Schizophrenia patients with CI do not seem to benefit as well as schizophrenia patients without CI from aerobic exercise training interventions. Larger, prospective randomized controlled clinical trials with different training interventions are urgently needed to address the topic of schizophrenia patients not responding to exercise and the relationship to the illness itself.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fpsyt.2019.00090DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6424878PMC
March 2019

The Use of Physiological Signals in Brainstem/Midbrain fMRI.

Front Neurosci 2018 16;12:718. Epub 2018 Oct 16.

Psychiatric Brain and Body Research Group Jena, Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany.

Brainstem and midbrain nuclei are closely linked to cognitive performance and autonomic function. To advance the localization in this area, precise functional imaging is fundamental. In this study, we used a sophisticated fMRI technique as well as physiological recordings to investigate the involvement of brainstem/midbrain nuclei in cognitive control during a Stroop task. The temporal signal-to-noise ratio (tSNR) increased due to physiological noise correction (PNC) especially in regions adjacent to arteries and cerebrospinal fluid. Within the brainstem/cerebellum template an average tSNR of 68 ± 16 was achieved after the simultaneous application of a high-resolution fMRI, specialized co-registration, and PNC. The analysis of PNC data revealed an activation of the substantia nigra in the Stroop interference contrast whereas no significant results were obtained in the midbrain or brainstem when analyzing uncorrected data. Additionally, we found that pupil size indicated the level of cognitive effort. The Stroop interference effect on pupillary responses was correlated to the effect on reaction times ( = 0.464, < 0.05). When Stroop stimuli were modulated by pupillary responses, we observed a significant activation of the LC in the Stroop interference contrast. Thus, we demonstrated the beneficial effect of PNC on data quality and statistical results when analyzing neuronal responses to a cognitive task. Parametric modulation of task events with pupillary responses improved the model of LC BOLD activations in the Stroop interference contrast.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnins.2018.00718DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6198067PMC
October 2018

Activation of brainstem and midbrain nuclei during cognitive control in medicated patients with schizophrenia.

Hum Brain Mapp 2019 01 5;40(1):202-213. Epub 2018 Sep 5.

Psychiatric Brain and Body Research Group Jena, Department of Psychiatry and Psychotherapy, University Hospital Jena, Jena, Germany.

Evidence suggests that cognitive control functions as well as the underlying brain network, anchored by the prefrontal cortex (PFC) and the dorsal anterior cingulate cortex (dACC), are dysfunctional in schizophrenia. Catecholamine producing midbrain and brainstem nuclei are densely connected with the PFC and dACC and exert profound contributions to cognitive control processes. Dysfunctions within the underlying neurotransmitter systems are considered to play a central role in the occurrence of various symptoms of schizophrenia. We sought to investigate the putatively abnormal activation pattern of the dopaminergic midbrain nuclei, that is, ventral tegmental area (VTA) and substantia nigra as well as that of the noradrenergic locus coeruleus (LC) in patients with schizophrenia during cognitive control. A total of 28 medicated patients and 27 healthy controls were investigated with the manual version of the Stroop task using event-related fMRI. The main finding was a reduced BOLD activation in the VTA during both Stroop task conditions in patients in comparison to controls, which correlated significantly with the degree of negative symptoms. We further detected a comparable LC activation in in patients and healthy controls. However, in controls LC activation was significantly correlated with the Stroop interference time, which was not observed in patients. The finding of reduced VTA activation in schizophrenia patients lends further support to the assumed dysfunction of the DA system in schizophrenia. In addition, despite comparable LC activation, the nonsignificant correlation with the Stroop interference time might indicate altered LC functioning in schizophrenia and, thus, needs further investigations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/hbm.24365DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6865428PMC
January 2019

Towards response success prediction: An integrative approach using high-resolution fMRI and autonomic indices.

Neuropsychologia 2018 10 6;119:182-190. Epub 2018 Aug 6.

Psychiatric Brain and Body Research Group, Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany. Electronic address:

Brainstem and midbrain nuclei are closely linked to effective cognitive performance and autonomic function. In the present study, we aimed to investigate indices of successful and unsuccessful response inhibition paying particular attention to the interplay between locus coeruleus (LC), ventral tegmental area (VTA)/substantia nigra (SN) and, most importantly, peripheral markers. We aimed to get insight in the predictive value of neural and physiological signals in response inhibition. A total of 35 healthy controls were recruited from the local community and a typical task of behavioral response inhibition (Go/No-Go paradigm) was applied. We used high-resolution fMRI, advanced brainstem analyses and specifically corrected for respiratory signal and cardiac noise. Our main results characterize specific neural activation patterns during successful and unsuccessful response inhibition especially comprising the anterior cingulate as well as the medial and lateral prefrontal cortex. A significant activation of the dopaminergic nuclei (VTA/SN) was found during error processing, but not during response inhibition. Most remarkably, specific neural activation patterns (i.e., dorsal anterior cingulate cortex) as well as accompanying autonomic indices (i.e., skin conductance response (SCR)) were identified to hold predictive information on an individual's performance. In summary, the importance of the VTA/SN during error processing was shown. Furthermore, autonomic indices and specific neural activation patterns may contain valuable information to predict task performance.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.neuropsychologia.2018.08.003DOI Listing
October 2018

Multivariate assessment of the central-cardiorespiratory network structure in neuropathological disease.

Physiol Meas 2018 07 20;39(7):074004. Epub 2018 Jul 20.

Institute of Innovative Health Technologies, Ernst-Abbe-Hochschule Jena, Jena, Germany. Department of Pediatrics, Division of Oncology and Hematology, Charité Universitätsmedizin, Berlin, Germany.

Objective: The new interdisciplinary field of network physiology is increasingly becoming a focus of interest in medicine. Autonomic nervous system (ANS) dysfunction is well described in schizophrenia (SZO). However, the linear and nonlinear coupling between the ANS and central nervous system (CNS) has only been partly addressed until now. This coupling can be assumed to be a feedback-feedforward network, reacting with flexible and adaptive responses to internal and external factors.

Approach: For the first time, in this study we investigated linear and nonlinear short-term central-cardiorespiratory coupling of 17 patients suffering from paranoid SZO in comparison to 17 age-gender matched healthy subjects analyzing heart rate (HR), respiration (RESP), and the power of frontal electroencephalogram (EEG) activity (P ). The objective is to determine how the different regulatory aspects of the CNS-ANS affect the central-cardiorespiratory network (CCRN). To quantify these couplings within the CCRN normalized short time partial directed coherence and the new multivariate high-resolution joint symbolic dynamics were applied.

Main Results: We found that the CCRN in SZO can be characterized as a bidirectional one, with stronger central driving mechanisms (P   →  HR) towards HR regulation than vice versa, and with stronger respiratory influence (RESP  →  P ) on central activity than vice versa. This suggests that the central-cardiorespiratory process (closed-loop) is mainly focused on adapting the HR via the sinoatrial node than focusing on respiratory regulation. On the other hand, the feedback-loop from ANS to CNS is strongly dominated via respiratory activity.

Significance: We demonstrated a considerably significantly different CCRN structure in SZO with a strong central influence on the cardiac system and a strong respiratory influence on the CNS. Moreover, this study provides a more in-depth understanding of the interplay of the central and autonomic regulatory network in healthy subjects and SZO patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1088/1361-6579/aace9bDOI Listing
July 2018

Multivariate assessment of the central-cardiorespiratory network structure in neuropathological disease.

Physiol Meas 2018 07 20;39(7):074004. Epub 2018 Jul 20.

Institute of Innovative Health Technologies, Ernst-Abbe-Hochschule Jena, Jena, Germany. Department of Pediatrics, Division of Oncology and Hematology, Charité Universitätsmedizin, Berlin, Germany.

Objective: The new interdisciplinary field of network physiology is increasingly becoming a focus of interest in medicine. Autonomic nervous system (ANS) dysfunction is well described in schizophrenia (SZO). However, the linear and nonlinear coupling between the ANS and central nervous system (CNS) has only been partly addressed until now. This coupling can be assumed to be a feedback-feedforward network, reacting with flexible and adaptive responses to internal and external factors.

Approach: For the first time, in this study we investigated linear and nonlinear short-term central-cardiorespiratory coupling of 17 patients suffering from paranoid SZO in comparison to 17 age-gender matched healthy subjects analyzing heart rate (HR), respiration (RESP), and the power of frontal electroencephalogram (EEG) activity (P ). The objective is to determine how the different regulatory aspects of the CNS-ANS affect the central-cardiorespiratory network (CCRN). To quantify these couplings within the CCRN normalized short time partial directed coherence and the new multivariate high-resolution joint symbolic dynamics were applied.

Main Results: We found that the CCRN in SZO can be characterized as a bidirectional one, with stronger central driving mechanisms (P   →  HR) towards HR regulation than vice versa, and with stronger respiratory influence (RESP  →  P ) on central activity than vice versa. This suggests that the central-cardiorespiratory process (closed-loop) is mainly focused on adapting the HR via the sinoatrial node than focusing on respiratory regulation. On the other hand, the feedback-loop from ANS to CNS is strongly dominated via respiratory activity.

Significance: We demonstrated a considerably significantly different CCRN structure in SZO with a strong central influence on the cardiac system and a strong respiratory influence on the CNS. Moreover, this study provides a more in-depth understanding of the interplay of the central and autonomic regulatory network in healthy subjects and SZO patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1088/1361-6579/aace9bDOI Listing
July 2018

Quantification of the Central Cardiovascular Network Applying the Normalized Short-time Partial Directed Coherence Approach in Healthy Subjects.

Methods Inf Med 2018 05 2;57(3):129-134. Epub 2018 May 2.

Background: The central control of the autonomic nervous system (ANS) and the complex interplay of its components can be described by a functional integrated mode - the central autonomic network (CAN). CAN represents the integrated functioning and interaction between the central nervous system (CNS) and ANS (parasympathetic and sympathetic activity).

Objective: This study investigates the central cardiovascular network (CCVN) as a part of the CAN, during which heart rate (HR), systolic blood pressure (SYS) and frontal EEG activity in 21 healthy subjects (CON) will be analysed. The objective of this study is to determine how these couplings (central-cardiovascular) are composed by the different regulatory aspects of the CNS-ANS interaction.

Methods: To quantify the short-term instantaneous causal couplings within the CCVN, the normalized short time partial directed coherence (NSTPDC) approach was applied. It is based on an m-dimensional MAR process to determine Granger causality in the frequency domain.

Results: We found that CCVN were of bidirectional character, and that the causal influences of central activity towards HR were stronger than those towards systolic blood pressure. This suggests that the central-cardiac closed-loop regulation process in CON focuses mainly on adapting the heart rate via the sinoatrial node rather than focusing on SYS. The CNS-ANS coupling directions with respect to central spectral power bands were characterized as mostly bidirectional, where HR and SYS acted as drivers in nearly every frequency band (unidirectional for α, α and α).

Conclusion: This study provides a more indepth understanding of the interplay of neuronal and autonomic cardiovascular regulatory processes in healthy subjects, as well as a greater insight into the complex CAN.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3414/ME17-02-0002DOI Listing
May 2018

Symptoms of Anxiety and Depression in Young Athletes Using the Hospital Anxiety and Depression Scale.

Front Physiol 2018 7;9:182. Epub 2018 Mar 7.

Department of Sports Medicine and Health Promotion, Friedrich Schiller University Jena, Jena, Germany.

Elite young athletes have to cope with multiple psychological demands such as training volume, mental and physical fatigue, spatial separation of family and friends or time management problems may lead to reduced mental and physical recovery. While normative data regarding symptoms of anxiety and depression for the general population is available (Hinz and Brähler, 2011), hardly any information exists for adolescents in general and young athletes in particular. Therefore, the aim of this study was to assess overall symptoms of anxiety and depression in young athletes as well as possible sex differences. The survey was carried out within the scope of the study "Resistance Training in Young Athletes" (KINGS-Study). Between August 2015 and September 2016, 326 young athletes aged (mean ± SD) 14.3 ± 1.6 years completed the Hospital Anxiety and Depression Scale (HAD Scale). Regarding the analysis of age on the anxiety and depression subscales, age groups were classified as follows: late childhood (12-14 years) and late adolescence (15-18 years). The participating young athletes were recruited from Olympic weight lifting, handball, judo, track and field athletics, boxing, soccer, gymnastics, ice speed skating, volleyball, and rowing. Anxiety and depression scores were (mean ± SD) 4.3 ± 3.0 and 2.8 ± 2.9, respectively. In the subscale anxiety, 22 cases (6.7%) showed subclinical scores and 11 cases (3.4%) showed clinical relevant score values. When analyzing the depression subscale, 31 cases (9.5%) showed subclinical score values and 12 cases (3.7%) showed clinically important values. No significant differences were found between male and female athletes ( ≥ 0.05). No statistically significant differences in the HADS scores were found between male athletes of late childhood and late adolescents ( ≥ 0.05). To the best of our knowledge, this is the first report describing questionnaire based indicators of symptoms of anxiety and depression in young athletes. Our data implies the need for sports medical as well as sports psychiatric support for young athletes. In addition, our results demonstrated that the chronological classification concerning age did not influence HAD Scale outcomes. Future research should focus on sports medical and sports psychiatric interventional approaches with the goal to prevent anxiety and depression as well as teaching coping strategies to young athletes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2018.00182DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5845908PMC
March 2018

Chronotropic incompetence of the heart is associated with exercise intolerance in patients with schizophrenia.

Schizophr Res 2018 07 9;197:162-169. Epub 2018 Mar 9.

Psychiatric Brain and Body Research Group, Department of Psychiatry and Psychotherapy, University Hospital Jena, Germany. Electronic address:

The elevated cardiovascular risk of patients with schizophrenia contributes to a reduced life expectancy of 15-20years. This study investigated whether cardiac autonomic dysfunction (CADF) in schizophrenia is related to chronotropic incompetence, an established cardiovascular risk marker. We investigated thirty-two patients suffering from paranoid schizophrenia and thirty-two control subjects matched for age, sex, body mass index and fat free mass. A cardiopulmonary exercise test (CPET) was performed to study heart rate responses to exercise as well as submaximal (ventilatory threshold 1, VT) and maximal endurance capacities (peak oxygen consumption, VO; peak power output, P). In addition, epinephrine and norepinephrine levels were assessed in a subset of patients. Fitness parameters were significantly reduced in all patients. Most investigated physiological parameters were significantly different at rest as well as during peak exercise being in line with previously described CADF in schizophrenia. In particular, 14 out of 32 patients were classified as chronotropically incompetent whereas no control subject was below the cut-off value. In addition, a positive correlation of a slope reflecting chronotropic incompetence with peak oxygen uptake (p<0.001) was observed in patients only indicating a close correlation to the lack of physical fitness. The catecholamine increase was reduced in patients after exercise. This study identified a novel cardiac risk factor in patients with schizophrenia. Moreover, it seems to be associated with reduced physical fitness and indicates targets for exercise intervention studies. Future studies are warranted to elucidate pathophysiological mechanisms of this cardiac condition.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.schres.2018.02.020DOI Listing
July 2018

Chronotropic incompetence of the heart is associated with exercise intolerance in patients with schizophrenia.

Schizophr Res 2018 07 9;197:162-169. Epub 2018 Mar 9.

Psychiatric Brain and Body Research Group, Department of Psychiatry and Psychotherapy, University Hospital Jena, Germany. Electronic address:

The elevated cardiovascular risk of patients with schizophrenia contributes to a reduced life expectancy of 15-20years. This study investigated whether cardiac autonomic dysfunction (CADF) in schizophrenia is related to chronotropic incompetence, an established cardiovascular risk marker. We investigated thirty-two patients suffering from paranoid schizophrenia and thirty-two control subjects matched for age, sex, body mass index and fat free mass. A cardiopulmonary exercise test (CPET) was performed to study heart rate responses to exercise as well as submaximal (ventilatory threshold 1, VT) and maximal endurance capacities (peak oxygen consumption, VO; peak power output, P). In addition, epinephrine and norepinephrine levels were assessed in a subset of patients. Fitness parameters were significantly reduced in all patients. Most investigated physiological parameters were significantly different at rest as well as during peak exercise being in line with previously described CADF in schizophrenia. In particular, 14 out of 32 patients were classified as chronotropically incompetent whereas no control subject was below the cut-off value. In addition, a positive correlation of a slope reflecting chronotropic incompetence with peak oxygen uptake (p<0.001) was observed in patients only indicating a close correlation to the lack of physical fitness. The catecholamine increase was reduced in patients after exercise. This study identified a novel cardiac risk factor in patients with schizophrenia. Moreover, it seems to be associated with reduced physical fitness and indicates targets for exercise intervention studies. Future studies are warranted to elucidate pathophysiological mechanisms of this cardiac condition.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.schres.2018.02.020DOI Listing
July 2018