Effects of nutritive and non-nutritive sucking on infant heart rate variability during the first 6 months of life

The effects of eating on heart rate variability (HRV) differ between adults and newborns. This may reflect the impact of suckling on the overall psychophysiological and autonomic nervous system maturation. The purpose of the present study was to explore whether the reactions of HRV during feeding change towards the adult pattern during the first 6 months of life. In addition, the effects of non-nutritive and nutritive sucking on heart rate (HR) and HRV were compared. The participants were 23 infants on whom recordings were performed as newborns and at 6, 12 and 24 weeks old. Nutritive sucking caused an increase in HR and a decline in HRV. The results were consistent with previous reports of a decrease in high frequency components of HRV during feeding in newborns, reflecting a decrease in parasympathetic activity. This response was apparent in all four ages studied, and remained similar throughout the 6-month period. However, age as an independent factor seemed to influence both HR and HRV. Pacifier sucking had no significant effects on HRV at any age. The results demonstrate the physical strain that sucking imposes on the baby, with a specific autonomic nervous system response involved. We consider this response an essential part of the overall psychophysiological maturation of infants.     

心率变异性在心身疾病和情绪障碍研究中的应用

心率变异性的频谱成分可单独反映交感神经和副交感神经活动的影响。高频（HF）是由迷走神经单独介导；低频（LF）受迷走神经和交感神经共同调制，但主要反映交感神经的活动性 。此指标可对高血压、冠心病和月经前期烦躁等心身障碍进行评价。该文还探讨了它用于情绪研究的价值，并认为在不同情绪体验期间的自主神经活动有多种搭配模式，正常人与情绪障碍者之间以及情绪障碍（抑郁、焦虑、恐怖、强迫）患者在自主神经活动方面可能存在显著差别     

Low heart rate variability is not caused by typical neuroleptics in schizophrenia patients

Both elevated cardiovascular mortality and low cardio-vagal (parasympathetic) heart rate variability (HRV)--a risk factor for postmyocardial infarction--are reported in schizophrenia (SZ). Since a number of medications have strong effects of cardiac conductivity, we thought it important to examine if typical neuroleptic medications might also affect HRV. We examined cardiac vagal activity during both neuroleptic treatment and a drug-free condition in seven SZ patients who were participating in a pilot double-blind, crossover study of placebo and haloperidol treatment. Twenty-four-hour Holter electrocardiograms were analyzed for high frequency HRV, quantitated as the percent of successive normal interbeat intervals greater than 50 milliseconds (PNN50), which is a good index of parasympathetic cardiac modulation. The patients showed unchanged PNN50 (8.4+/-9.5 versus 8.3+/-10.5; t=.22, df=6, P=.5) between the haloperidol treatment and drug-free conditions. Despite the elapsed time, change in medication, and altered clinical state, the PNN50s were highly correlated (Spearman r=.98, P=.000). SAPS positive symptom scores declined with treatment from 12.8+/-6.5 to 8.5+/-3.5; paired t=3.26: df=6; P=.01. PNN50s were significantly associated with positive (r=-.86, df=6, P=.012) and negative symptom scores (r=-.87, df=6, P=.01). We found low cardiovagal modulation in medication-free SZ patients that was associated with core SZ symptoms and was unchanged by haloperidol and benztropine treatment. The reduced HRV in SZ patients at baseline may render them at greater cardiovascular risk than healthy subjects when treated with medications having strong cardiovascular effects.     

Compassion at the mirror: Exposure to a mirror increases the efficacy of a self-compassion manipulation in enhancing soothing positive affect and heart rate variability

We tested whether a mirror could enhance the efficacy of a self-compassion manipulation in increasing soothing positive affect and heart rate variability (HRV). Eighty-six participants generated four phrases they would use to soothe and encourage their best friend. Second, they described an episode where they criticized themselves and were assigned to one of three conditions: (a) repeat the four phrases to themselves while looking at the mirror; (b) repeat the four phrases to themselves without the mirror; (c) look at themselves in the mirror without repeating the phrases. Participants in condition (a) reported higher levels of ‘soothing’ positive affect and HRV compared to participants in conditions (b) and (c). The effect of the ‘phrases at the mirror’ manipulation on soothing affect was mediated by increased common humanity. The mirror enhances the efficacy of this self-compassion manipulation in activating the soothing affect system connected with parasympathetic nervous system activity.     

Field validity of heart rate variability metrics produced by QRSTool and CMetX

Interest in heart rate variability (HRV) metrics as markers of physiological and psychological health continues to grow beyond those with psychophysiological expertise, increasing the importance of developing suitable tools for researchers new to the field. Allen, Chambers, and Towers (2007) developed QRSTool and CMetX software as simple, user-friendly tools that can be used to compute metrics of HRV. In the present study, the authors examined the field validity of these software tools-that is, their validity when used by nonexperts. In a lab with extensive expertise in psychopathology but not psychophysiology, ECG data were obtained from 63 undergraduates at baseline and during a stressor and then processed using QRSTool and CMetX to produce the 10 HRV indices described in Allen et al. (2007). The indices displayed factor structures and patterns of changes from baseline to stressor that were similar to findings from Allen et al. and consistent with how indices of parasympathetic and sympathetic activity should behave. Results support the field validity of QRSTool and CMetX, suggesting that they are useful for nonexperts in psychophysiology interested in measuring HRV. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Mental relaxation improves long-term incidental visual memory

Experimental evidence has linked increased arousal to enhanced memory retention. There is also evidence that procedures reducing arousal, i.e., mental relaxation, might improve memory, but conflicting results have been reported. To clarify this issue, we studied the effects of a single session of relaxation training on incidental visual long-term memory. Thirty-two relaxation-naive subjects viewed 280 slides without being told that there would be subsequent memory testing. Afterwards, subjects listened to a 12 min relaxation tape; 16 subjects relaxed by following the instructions (relaxation group), and the other 16 subjects pressed a button whenever a body part was mentioned (control group). While listening to the relaxation tape, high frequency heart rate variability (HRV) was greater and low frequency HRV was lower in the relaxation group, implying effective relaxation and increasing parasympathetic activation. The relaxation group had superior memory retention 4 weeks later (p = .004), indicating enhancement of long-term memory performance. This effect could not be explained by retroactive interference experienced in the control group because short-term memory performance immediately after the tape was slightly better in the control group. Retention of materials acquired after the relaxation session remained unaffected, suggesting relaxation has retrograde effects on memory consolidation. Our data demonstrate a favorable influence of relaxation on at least this aspect of learning. Our data also extend previous knowledge on the beneficial effects of ascending parasympathetic stimulation on memory retention in that enhanced long-term memory consolidation may also occur in the presence of central and descending parasympathetic activation triggered by willful psychomotor activity.     

Effects of short-term psychological stress on the time and frequency domains of heart-rate variability

The purpose of this study was to test the hypothesis that short-term psychological stress produces significant changes in sympathovagal activity. A simple, noninvasive method was used measuring the timing and frequency of heart-rate variability (HRV). 30 normal healthy subjects were assigned into two age- and sex matched groups. In the experimental condition a 5-min. psychological stress test, predominantly based on the Stroop Word Color Conflict Test, was employed in a competitive setting and included a financial inducement to produce psychological strain. Analysis showed that during psychological stress a significant reduction in the timing and frequency of heart rate variability was observed. The standard deviation of interbeat intervals decreased. A significant increase in heart rate was also observed. Within the frequency domain, a significant reduction in the high frequency component of HRV and a significant increase in the low frequency component were observed. There was also a significant increase in the low frequency to high frequency ratio. Self-evaluation of physical tension and emotional state measured by visual analog scales also showed significant increases following psychological stress. No significant differences were observed on any variables within the control group. The results indicate a shift towards sympathetic predominance as a result of parasympathetic withdrawal and demonstrates that this psychological stress test is effective in provoking a characteristic defence-arousal reaction. This simple, cost-effective method of analysing heart rate variability is suitable for detection of short-term changes in sympathovagal balance.     

Experimental manipulation of maternal proximity during short sequences of sleep and infant calming response

This study aimed to understand how different mother-infant sleeping arrangements impact infants’ self-regulation, particularly their calming response. Thus this study investigated the effect of three prevalent mother-infant sleeping arrangements, co-sleeping (CS), sleeping beyond arm’s length from their mother (BAL), and solitary sleeping (SS), on infants’ physiological calming through self-regulation during a nap session in 24 infants (50% female, M = 1.85 months SD = 0.93 months), who were identified as either regular co-sleepers with their mothers, infants who slept in the BAL sleeping arrangement from their mother, and infants who are solitary sleepers (SS). The effect of all three sleeping conditions amongst all the three types of infants with different habitual sleeping arrangements was assessed. All infants spent 10 min (2 × 5 min sessions) in each sleeping condition (CS, BAL, SS) during which electrocardiographic recordings were collected to obtain interbeat intervals (IBI) and rMSSD, a measure of heart rate variability (HRV) an index of physiological calming, maintained by the parasympathetic pathway involved in self-regulation. Infants who regularly co-slept with their mothers had the highest IBI, indicating greater physiological calming and self-regulation across all sleeping arrangement conditions (CS, BAL, SS), followed by infants who regularly slept in the BAL sleeping arrangement from their mothers. IBI was lowest amongst regular solitary sleepers, potentially indicating physiological stress due to mother-infant separation. However, HRV indices during the sleeping arrangements (especially across regular solitary sleepers) were inconclusive as to whether the lack of change in HRV across all sleeping conditions was due to physiological stress responses or greater physiological regulation. This study is the first to investigate the effect of manipulated and habitual mother-infant sleeping arrangements on infant physiological calming.     

不同心理刺激诱发的交感和副交感神经活动的比较

让24名女大学生被试完成划消测验、镜画测验、心算和准备演讲四种应激任务,目的在于探讨在不同心理刺激下交感和副交感神经系统的活动是否存在差异。记录HRV（Heart Rate Variability,心率变异性）的频域成分TP（Total Power,总功率）、HF（High Frequency,高频）、LF（Low Frequency,低频）、LF/HF（低频高频比）、平均R-R间期和血压等指标在基线和不同应激任务期间的变化。通过单因素重复测量方差分析和多重比较发现,准备演讲期间的TP、LF值显著地高于基线和其它三项任务, HF的值显著地高于划消测验和心算;镜画测验、划消测验和心算期间的LF值与基线比较显著下降,TP、LF和HF三项指标在这三项任务之间无显著差异;不同任务期间在LF/HF上无显著主效应。平均R-R间期基线水平与所有任务间的比较及各任务之间有显著差异。收缩压基线水平与划消、镜画任务间的比较有显著差异。结果表明,准备演讲期间的交感神经和副交感神经张力显著地大于其它任务,不同任务表现出的不同的自主神经张力变化说明交感神经与副交感神经活动不是一方活动增强、另一方活动减弱的单纯的活动方式,这一结果为Berntson提出的自主神经活动可能存在九种活动搭配模式的理论提供了实验证据     

Electroencephalographic and autonomic alterations in subjects with frequent nightmares during pre-and post-REM periods

Abnormal arousal processes, sympathetic influences, as well as wake-like alpha activity during sleep were reported as pathophysiological features of Nightmare Disorder. We hypothesized that in Nightmare Disorder, wake-like cortical activity and peripheral measures linked to arousals would be triggered by physiological processes related to the initiation of REM periods. Therefore, we examined electroencephalographic (EEG), motor and autonomous (cardiac) activity in a group of nightmare (NM) and healthy control (CTL) subjects during sleep-state-transitions while controlling for the confounding effects of trait anxiety. Based on the second-nights’ polysomnographic recordings of 19 Nightmare Disordered (NM) and 21 control (CTL) subjects, we examined the absolute power spectra focusing on the alpha range, measures of heart rate variability (HRV) and motor (muscle tone) activity during pre-REM and post-REM periods, separately. According to our results, the NM group exhibited increased alpha power during pre-REM, but not in post-REM, or stable, non-transitory periods. While CTL subjects showed increased HRV during pre-REM periods in contrast to post-REM ones, NM subjects did not exhibit such sleep state-specific differences in HRV, but showed more stable values across the examined sleep stages and less overall variability reflecting generally attenuated parasympathetic activity during sleep-state-transitions and during stable, non-transitory NREM states. These differences were not mediated by waking levels of trait anxiety. Moreover, in both groups, significant differences emerged regarding cortical and motor (muscle tone) activity between pre-REM and post-REM conditions, reflecting the heterogeneity of NREM sleep. Our findings indicate that NM subjects’ sleep is compromised during NREM–REM transitions, but relatively stabilized after REM periods. The coexistence of sleep-like and wake-like cortical activity in NM subjects seems to be triggered by REM/WAKE promoting neural activity. We propose that increased arousal-related phenomena in NREM–REM transitions might reflect altered emotional processing in NM subjects.     

The impact of an emotional self-management skills course on psychosocial functioning and autonomic recovery to stress in middle school children

Unmanaged emotional reactions to stress not only lead to behavior problems in young people but also create physiological conditions that inhibit learning and potentially increase the risk of disease later in life. For these reasons, the integration of emotional self-management skills training programs has become an increased priority in some schools. In this study, middle school students enrolled in a course in emotional competence skills learned techniques designed to intercept stressful responses during emotionally challenging situations. Behavioral outcomes were assessed using the Achievement Inventory Measure and autonomic function was measured by heart rate variability (HRV) analysis during and after a stressful interview. Following the program, students exhibited significant improvements in areas including stress and anger management, risky behavior, work management and focus, and relationships with family, peers and teachers. These improvements were sustained over the following six months. Students using the skills taught in the course to recover from acute emotional stress were also able to positively modulate their physiological stress responses. As compared to a control group, trained students demonstrated significantly increased HRV and more rhythmic, sine wave-like heart rhythm patterns during recovery. This response pattern reflects increased parasympathetic activity, heart rhythm coherence, and entrainment of other biological oscillatory systems to the primary heart rhythm frequency. Increased physiological coherence is associated with improved cognitive performance, emotional balance, mental clarity and health outcomes. These physiological shifts could promote the sustained psychological and behavioral improvements associated with the use of emotional management skills. It is suggested that learning emotional competence skills in childhood establishes healthier physiological response patterns which can benefit learning and long-term health. Results provide support for the integration in school curricula of courses designed to teach effective self-management skills to children.     

心率变异性与人格的神经质之间关系研究

本研究探讨心率变异性（HRV）特征在高水平应激条件下对神经质水平的区分力。研究选取200名被试以大五人格量表测量情绪稳定性,实施了应激诱发实验,利用光体积扫描传感器采集被试者HRV指标;利用LASSO回归分析筛选参数构建对神经质的预测模型。结果显示：模型的预测数据与神经质得分高低显著正相关;不同阶段内预测数据与神经质得分显著正相关;两两比较中实验条件阶段与其他阶段预测值差异显著。研究表明,在高应激条件下,HRV是人格神经质较好的预测指标。     

Modifying the Rorschach Human Experience Variable to create the Human Representational Variable

The Human Experience Variable (HEV; Perry & Viglione, 1991) provided information about interpersonal perceptions not previously available within the Comprehensive System (CS; Exner, 1993). Research data suggests that it was related to interpersonal functioning and as a result, psychological impairment and health. In this article, we present the rationale and empirical basis for recent psychometric refinements to the HEV, consequently renamed the Human Representational Variable (HRV). Research addressing the reliability and validity for the HRV is summarized. Based on data and experience with the HEV, this study summarized some small modifications to the original algorithm. The refined variable, the HRV, has been added to the CS (Exner, 2000). Data presented here suggest that the HRV has improved psychometric properties compared to the HEV and that it is simpler to understand. Research recommendations and interpretive suggestions are also presented.     

Compassion-focused reappraisal,benefit-focused reappraisal,and rumination after an interpersonal offense: Emotion-regulation implications for subjective emotion,linguistic responses,and physiology

This repeated measures psychophysiology experiment studied three responses to a past interpersonal offense (38 females and 33 males). We compared rumination with two offense reappraisal strategies. Compassion-focused reappraisal emphasized the offender's humanity, and interpreted the transgression as evidence of the offender's need for positive transformation. Benefit-focused reappraisal emphasized insights gained or strengths shown in facing the offense. Supporting the manipulations, compassion-focused reappraisal stimulated the most empathy and forgiveness, whereas benefit-focused reappraisal prompted the most benefit language and gratitude. Both reappraisals decreased aroused, negative emotion, and related facial muscle tension at the brow (corrugator). Both reappraisals increased happiness and positive emotion in ratings and linguistic analyses. Compassion stimulated the greatest social language, calmed tension under the eye (orbicularis oculi), and slowed heart beats (R–R intervals). A focus on benefits prompted the greatest joy, stimulated smiling (zygomatic) activity, and buffered the parasympathetic nervous system against rumination's adverse effects on heart rate variability (HRV).     

Moderating effects of the valence of social interaction on the dysfunctional consequences of perseverative cognition: an ecological study in major depression and social anxiety disorder

Background and Objectives: Major depression disorder (MDD) and social anxiety disorder (SAD) are characterized by the use of perseverative cognition (PC) as a dysfunctional coping strategy. We sought to investigate the dysfunctional physiological and psychological consequences of PC and how the valence of social interactions moderates such consequences in these psychopathological conditions.

Design/Methods: The study combined 24-hour heart rate variability (HRV) and ecological momentary assessments in 48 individuals with MDD, SAD, and sex-matched controls.

Results: In all participants, PC was associated with mood worsening and reduced ability of the parasympathetic nervous system, mainly the vagus, to inhibit sympathetic arousal (i.e., reduced HRV). Individuals with SAD had the highest frequency of daily PC, while those with MDD reported that PC interfered more with their ongoing activities. In SAD, daily PC was associated with significantly lower HRV after negative social interactions. Individuals with MDD reported higher levels of sadness during PC irrespective of the valence of the preceding social interaction but higher levels of anxiety and efforts to inhibit PC following positive interactions.

Conclusions: Results highlight the need to account for important moderators like the valence of social interaction when looking at the physiological consequences of maladaptive emotion regulation strategies.     

An experimental study on mother-infant skin-to-skin contact in full-terms

In premature infants, daily skin-to-skin contact (SSC) has various beneficial effects on the health of the infant and the mother. These beneficial effects might extend to full-term infants. This experimental within-subject study examines the immediate effects of SSC on full-terms’ cortisol physiology during SSC and subsequent physiological and behavioral reactions to a mild stressor (a bathing session). Additionally, the effects of SSC on the quality of maternal behavior are examined.Between 5 and 7 weeks postpartum, 17 full-term infant-mother dyads were visited at home twice. During one home visit, a bathing session was proceeded by 50 min of mother-infant SSC, while during the other visit the bathing session was proceeded by 50 min of the infant resting alone. The order of the home visits was counterbalanced. Infant salivary cortisol measures were taken to measure the cortisol response to the experimental condition (SSC versus solitary resting) and the bathing session. Furthermore, infant behavioral distress and the quality of maternal behavior during the bathing session were scored from videotapes.Two-way within-subject repeated measures ANOVA’s showed that, when compared to solitary resting, full-terms’ cortisol concentrations significantly decreased during SSC, followed by higher cortisol reactivity in response to the subsequent bathing session. No effects of SSC on infant behavioral distress and maternal caregiving behavior were found. Apparently, a single session of mother-infant SSC can affect infant cortisol physiology in full-term infants. Future SSC research is needed to investigate the neurobiological mechanisms and dose-response relations in full-term infants.     

The relation between early mother–infant skin‐to‐skin contact and later maternal sensitivity in South African mothers of low birth weight infants

The relation between early mother–infant skin‐to‐skin contact (SSC) and mothers' subsequent sensitivity to their low birth weight infants was investigated in a study of 12 mother–infant dyads who participated in a South African randomized control study of early SSC. The dyads were visited in the home when infants were under 1 year. Amounts of SSC were taken from hospital records and home interviews. Videotapes of mother–infant interactions in the home were scored for maternal sensitivity on the Maternal Behavior Q‐Sort (D.R. Pederson, G. Moran, & S. Bento, 1999) and the Maternal Behavior subscale of the Nursing Child Assessment Teaching Scale (G. Sumner & A. Spietz, 1994). Amount of SSC in infants' first 24 hr correlated with amount of SSC through the first month. Amount of SSC in infants' first 24 hr independently accounted for maternal sensitivity on both measures, indicating that early mother–infant SSC predicted subsequent maternal sensitivity.     

Potentiating ballistic limb movements through voluntary production of the stretch-shorten cycle.

The purpose of this study was to examine the effect of learning to produce voluntarily a basic biomechanical mechanism, the stretch-shorten cycle (SSC), on the acceleration of a ballistic arm movement. The task required an elbow flexion at maximal effort performed with the forearm resting upon a horizontal manipulandum. Subjects in three groups received either no augmented feedback, feedback concerning the velocity of the flexion, or a combination of feedback on velocity and feedback related to the rate of stretch of the SSC during 80 training trials. The training trials were preceded by a pretest and followed by a posttest without feedback. Analyses showed that the subjects receiving feedback concerning the SSC exhibited earlier and greater peak angular acceleration than the other groups. These findings provide evidence that acquiring the control of relevant, basic mechanisms like the SSC may be useful in facilitating tasks requiring limb movements of maximal effort.     

A shortened version of the Southern Illinois university speech situation checklist for the identification of speech-related anxiety

This study investigated the ability of the 51-item Southern Illinois University Speech Situation Checklist (SSC) to differentiate stutterers known to have high levels of speech-related anxiety from nonstutterers with normal levels of speech- related anxiety. Checklist responses of 65 randomly selected subjects (33 stutterers and 32 nonstutterers) were subjected to a stepwise discriminant analysis. The analysis identified a combination of 21 SSC items that had significant discriminative power. Subsequently, the derived discriminant equation achieved 93% accuracy in correctly classifying a hold-out sample of 29 subjects (14 stutterers and 15 nonstutterers). These results strongly suggest that the 21 items of the SSC identified by discriminant analysis may provide an effective screening device for identifying disfluent speakers who experience an abnormal amount of speech-related anxiety.