Our goal was to determine the contributions of sympathetic and parasympathetic activity to entropy measures of heart rate variability (HRV). We compared our results with two commonly used methods to analyze HRV: standard deviation (SDNN) and power spectral analysis (HF norm). Beat-by-beat analysis of R-R intervals was performed in conscious dogs. The R-R intervals were analyzed with approximate...

The role of the autonomic nervous system in secretory immunoglobulin A (sIgA) responses to laboratory challenge was explored in a study in which sIgA and cardiovascular activity were recorded at rest and during mental arithmetic and paced breathing. These tasks were selected to preferentially engage the sympathetic and parasympathetic nervous systems, respectively. Mental arithmetic elicited a ...

Long-term endurance training significantly influences how the autonomic nervous system controls heart function. Endurance training increases parasympathetic activity and decreases sympathetic activity in the human heart at rest. These two training-induced autonomic effects, coupled with a possible reduction in intrinsic heart rate, decrease resting heart rate. Long-term endurance training also ...

We conducted this study in an effort to characterize and understand vagal abnormalities in heart failure patients whose sympathetic activity is known. We measured sympathetic (peroneal nerve muscle sympathetic recordings and antecubital vein plasma norepinephrine levels) and vagal (R-R intervals and their standard deviations) activities in eight heart failure patients and eight age-matched heal...

Physical exercise is associated with parasympathetic withdrawal and increased sympathetic activity resulting in heart rate increase. The rate of post-exercise cardiodeceleration is used as an index of cardiac vagal reactivation. Analysis of heart rate variability (HRV) and complexity can provide useful information about autonomic control of the cardiovascular system. The aim of the present stud...

Abnormal autonomic activity in patients with schizophrenia has been reported, but how psychotic states influence the autonomic nervous system (ANS) has remained unclear due to methodological limitations. The influence of psychotic states on ANS activity in patients with schizophrenia was investigated using a recently developed method of analysis based on heart rate variability which assesses ca...

BACKGROUND Activation of the sympathetic nervous system has been extensively studied in patients with chronic heart failure, but the parasympathetic nervous system has received relatively little attention. The objective in this study was to investigate cardiac parasympathetic activity in chronic heart failure and to explore its relation to left ventricular function. METHODS Heart rate variabi...

Fifty asthmatic patients and 20 healthy control subjects, carefully age- and sex-matched, were subjected to seven standardized tests to evaluate their autonomic status. Due care was taken to remove factors which could interfere with results. Of the tests concerned with the parasympathetic system, the intravenous atropine test (p greater than 0.10) and heart rate response to standing (p greater ...

OBJECTIVE To examine the effect of kangaroo care on heart rate variability in a healthy preterm infant. DESIGN Case study. SETTING Private room on a postpartum unit. PARTICIPANT A mother-preterm infant dyad. INTERVENTION Kangaroo (skin-to-skin) care. MAIN OUTCOME MEASURE Heart rate variability, a noninvasive measurement of the sympathetic and parasympathetic components of the autonomi...

In a series of studies to understand interactions between taste sensation and salivary gland function, we are pursuing experiments to determine the autonomic nervous system control of von Ebner's lingual salivary glands. Electrical stimulation of the glossopharyngeal nerve, which contains the parasympathetic nerve supply to von Ebner's glands, caused a reduction in secretory granules of the gla...