A multi-process account of startle modulation during affective perception

Modulation of the startle reflex by sensory, attentional, and emotional processes was explored by presenting acoustic startle probes at various delays following picture onset. Within 500 ms of onset, blinks were first greatly facilitated and then inhibited, indicating prepulse facilitation and prepulse inhibition that did not vary with affect. Attention allocation to the picture continued across the viewing interval and was most pronounced for emotional pictures, as determined by attenuation of the P3 component to the startle probe. Startle potentiation for unpleasant pictures occurred later in the viewing interval and was strongest for highly arousing pictures. Taken together, the startle reflex during picture viewing is modulated by sequential and sometimes concurrent processes of prepulse facilitation, prepulse inhibition, attentional inhibition, and affective modulation, with reflex magnitude reflecting the net effect of multiple processes.     

Hostility and cardiovascular reactivity during marital interaction.

OBJECTIVE: Prior studies demonstrate that hostile persons respond to social stressors with heightened cardiovascular responses. This study examined the effects of individual differences in hostility and two experimentally manipulated social stressors on cardiovascular reactivity during marital interaction. METHODS: Sixty couples participated in a discussion task under conditions of high or low evaluative threat and while either agreeing or disagreeing with each other. Individual differences in hostility were assessed with the Buss-Perry Aggression Questionnaire. Participants' appraisal of their spouses' behavior during the interaction task was assessed with a standardized measure. Systolic and diastolic blood pressure and heart rate responses were recorded. RESULTS: Among husbands, hostility was associated with greater systolic blood pressure reactivity under high, but not low, threat. Appraisals suggested that this might be due to husbands' efforts to assert dominance in the interaction. Wives' hostility scores were unrelated to cardiovascular reactivity, but wives disagreeing with hostile husbands showed greater heart rate reactivity. CONCLUSIONS: Heightened cardiovascular reactivity to stressful marital interactions among hostile men provides additional evidence of the viability of this psychophysiologic mechanism as a link between hostility and health. The lack of effects among wives suggests sex differences in the social psychophysiology of hostility. Interpersonal concepts and methods are useful in the study of psychosocial risk factors and mechanisms.     

Hostility and cardiovascular reactivity in women during self-disclosure

Hostility has been inconsistently related to cardiovascular reactivity in studies of women. In this study we examined hostility in college-age women in relation to cardiovascular reactivity and mood during self-disclosure of a distressing event to an unknown man. Women in the self-disclosure condition had greater systolic blood pressure, anxiety, and depressed mood than participants in the nondisclosure condition independent of their level of hostility. Hostile women in the self-disclosure condition reported greater anger postexperiment than women in the other three groups, and anger was related to diastolic blood pressure. Anxiety and depressed mood were related to systolic blood pressure and diastolic blood pressure for low hostile women in the self-disclosure condition. Results suggest an interrelation of hostility with negative mood and reactivity that requires further study. We thank Doug Denney, Ph.D., Sam Green, Ph.D., Annette Stanton, Ph.D., and Janice Triplett, Ph.D., for their editorial and statistical assistance. We would also like to acknowledge the research assistants for their work on this project: Kendall Day, Derek Dummermuth, Nick Foley, Lisa Harvey, Catherine Hess, Tracy Klem, Jessica Larkin, Kristina McNelley, and Brian O’Neill.     

Point process time-frequency analysis of dynamic respiratory patterns during meditation practice

Respiratory sinus arrhythmia (RSA) is largely mediated by the autonomic nervous system through its modulating influence on the heart beats. We propose a robust algorithm for quantifying instantaneous RSA as applied to heart beat intervals and respiratory recordings under dynamic breathing patterns. The blood volume pressure-derived heart beat series (pulse intervals, PIs) are modeled as an inverse Gaussian point process, with the instantaneous mean PI modeled as a bivariate regression incorporating both past PIs and respiration values observed at the beats. A point process maximum likelihood algorithm is used to estimate the model parameters, and instantaneous RSA is estimated via a frequency domain transfer function evaluated at instantaneous respiratory frequency where high coherence between respiration and PIs is observed. The model is statistically validated using Kolmogorov–Smirnov goodness-of-fit analysis, as well as independence tests. The algorithm is applied to subjects engaged in meditative practice, with distinctive dynamics in the respiration patterns elicited as a result. The presented analysis confirms the ability of the algorithm to track important changes in cardiorespiratory interactions elicited during meditation, otherwise not evidenced in control resting states, reporting statistically significant increase in RSA gain as measured by our paradigm.     

Frontal electrocortical and cardiovascular reactivity during happiness and anger

The present study investigated electrocortical and cardiovascular reactivity during positive and negative emotion, and examined the relation of asymmetric frontal lobe activation to cardiovascular responses. Participants were 30 healthy, right-handed university students (mean age, 23.9; 60% female; 76% Caucasian). Electroencephalographic (EEG), blood pressure (BP), and heart rate (HR) responses were assessed while subjects engaged in laboratory tasks (personally-relevant recall tasks and film clips) designed to elicit happiness or anger. Happiness-inducing tasks evoked more prominent left than right frontal EEG activation, and greater left frontal EEG activation than anger-inducing tasks. However, anger-inducing tasks were, on average, associated with comparable left and right frontal EEG activation. Irrespective of emotional valence, cardiovascular activation was more pronounced during personally-relevant recall tasks than during the viewing of film clips. During anger recall, both greater left frontal EEG response (r=-0.46, P<0.02) and greater right frontal EEG response (r=-0.45, P<0.02) were correlated significantly with increased HR reactivity during the task. In addition, a right lateralized frontal EEG response during anger-inducing tasks was associated with greater concomitant systolic BP (P<0.03) and diastolic BP (P<0.008) reactivity. Exploratory analyses also indicated that men who displayed a left lateralized frontal EEG response during happiness-inducing tasks showed the greatest concomitant systolic BP and HR reactivity (P's<0.03). These findings suggest that asymmetric frontal EEG responses to emotional arousal may elicit different patterns of cardiovascular reactivity in healthy adults.     

Effects of meditation practice on spontaneous eyeblink rate

A rapidly growing body of research suggests that meditation can change brain and cognitive functioning. Yet little is known about the neurochemical mechanisms underlying meditation‐related changes in cognition. Here, we investigated the effects of meditation on spontaneous eyeblink rates (sEBR), a noninvasive peripheral correlate of striatal dopamine activity. Previous studies have shown a relationship between sEBR and cognitive functions such as mind wandering, cognitive flexibility, and attention–functions that are also affected by meditation. We therefore expected that long‐term meditation practice would alter eyeblink activity. To test this, we recorded baseline sEBR and intereyeblink intervals (IEBI) in long‐term meditators (LTM) and meditation‐naive participants (MNP). We found that LTM not only blinked less frequently, but also showed a different eyeblink pattern than MNP. This pattern had good to high degree of consistency over three time points. Moreover, we examined the effects of an 8‐week course of mindfulness‐based stress reduction on sEBR and IEBI, compared to an active control group and a waitlist control group. No effect of short‐term meditation practice was found. Finally, we investigated whether different types of meditation differentially alter eyeblink activity by measuring sEBR and IEBI after a full day of two kinds of meditation practices in the LTM. No effect of meditation type was found. Taken together, these findings may suggest either that individual difference in dopaminergic neurotransmission is a self‐selection factor for meditation practice, or that long‐term, but not short‐term meditation practice induces stable changes in baseline striatal dopaminergic functioning.     

Dominance, gender, and cardiovascular reactivity during social interaction

Associations between trait dominance and cardiovascular reactivity were examined in previously unacquainted healthy men and women. Subjects participated in three mixed-gender dyadic interactions with the same partner while their cardiovascular responses were assessed. Among men, but not women, trait dominance was positively and significantly associated with systolic blood pressure reactivity. For men and women, diastolic blood pressure reactivity was positively and significantly associated with trait dominance while participants prepared to interact and with partner's trait dominance while they interacted. All effects held after controlling for trait hostility. Dominance merits attention as a correlate of cardiovascular reactivity, a finding that parallels emerging patterns in the cardiovascular disease literature. Gender and gender-related social factors as potential moderators of this relationship are discussed.     

The effect of cognitive reappraisal on physiological reactivity and emotional memory

We investigated the effect of cognitive reappraisal on emotional arousal, facial expressivity and subsequent memory. Men and women viewed emotionally negative pictures while they attempted to either increase or decrease negative emotions elicited by the pictures, or to simply view the pictures. Neutral pictures were also presented with instructions to simply view the pictures. Concurrent changes in emotional arousal and valence were assessed with skin conductance responses (SCRs) and facial corrugator electromyographic responses (EMG), respectively. Picture memory was assessed with an immediate recall test and a delayed recognition test. Relative to simply viewing pictures, voluntary reappraisal to increase negative emotion generated greater facial corrugator EMG and SCR responses, and reappraisal to decrease negative emotion generated decreased corrugator EMG responses. Men showed enhanced recognition for pictures presented during the increase and decrease conditions, whereas women showed comparable recognition performance across all regulation conditions. The modulation of subsequent recognition memory associated with decreasing emotion was inversely associated with changes in physiological responses. Our results suggest that sex is an important factor to consider in determining how reappraisal-induced physiological changes are associated with subsequent changes in memory. These findings contribute to our understanding of how reappraising emotion exerts both immediate and enduring influences on physiological responses and subsequent memory.     

Impact of meditation on emotional processing--a visual ERP study

Impact of meditation on emotional processing, and its clinical applications, has recently drawn significant interest. In this visual event-related potential (ERP) study we investigated whether long-term meditation practitioners exhibit different ERP responses to the emotional load of stimuli (IAPS pictures) than control subjects with no experience in meditation. Differences were observed in the late positive potential (LPP). LPP amplitude is typically greater in ERPs evoked by emotionally arousing scenes, specifically negative images, compared to neutral scenes. This effect was also replicated in our study, but not in case of meditators’ frontal scalp regions, who differed significantly in this respect from control subjects. Our findings provide support for different emotional processing in meditation practitioners: at high levels of processing meditators are less affected by stimuli with adverse emotional load, while processing of positive stimuli remains unaltered. To further confirm this observation, a long-term longitudinal random assignment study would be desirable.     

The impact of statin therapy on long-term cardiovascular outcomes in an outpatient cardiology practice

Introduction

Statins reduce coronary events in patients with coronary artery disease.

Material and methods

Chart reviews were performed in 305 patients (217 men and 88 women, mean age 74 years) not treated with statins during the first year of being seen in an outpatient cardiology practice but subsequently treated with statins. Based on the starting date of statins use, the long-term outcomes of myocardial infarction (MI), percutaneous coronary intervention (PCI), and coronary artery bypass graft surgery (CABGs) before and after statin use were compared.

Results

Mean follow-up was 65 months before statins use and 66 months after statins use. Myocardial infarction occurred in 31 of 305 patients (10%) before statins, and in 13 of 305 patients (4%) after statins (p < 0.01). Percutaneous coronary intervention had been performed in 66 of 305 patients (22%) before statins and was performed in 41 of 305 patients (13%) after statins (p < 0.01). Coronary artery bypass graft surgery had been performed in 56 of 305 patients (18%) before statins and in 20 of 305 patients (7%) after statins (p < 0.001). Stepwise logistic regression showed statins use was an independent risk factor for MI (odds ratio = 0.0207, 95% CI, 0.0082-0.0522, p < 0.0001), PCI (odds ratio = 0.0109, 95% CI, 0.0038-0.0315, p < 0.0001) and CABGs (odds ratio = 0.0177, 95% CI = 0.0072-0.0431, p < 0.0001)

Conclusions

Statins use in an outpatient cardiology practice reduces the incidence of MI, PCI, and CABGs.     

Interactive effects of traits,states, and gender on cardiovascular reactivity during different situations

Interactive effects of anger and anxiety traits, negative affect state, different situations, and gender on cardiovascular reactivity (CVR) to stress were examined. Subjects (91 men, 92 women) performed a reaction time task under either a Social Evaluation, a Harassment, or a Control condition; SBP, DBP, and HR were recorded continuously. Hierarchical multiple regressions revealed intricate interactions. The interaction of anger expression style and anger experience was significant only among men, such that anger suppressors with high trait anger showed the largest CVR of any group during Harassment; anger expressors exhibited generally high CVR across conditions. However, anger expression style and state negative affect interacted to affect CVR in both men and women. Finally, the fear of negative evaluation predicted elevated DBP responses only among men in the Social Evaluation condition. Results imply that the extent to which traits of anger and anxiety contribute to coronary risk may depend on interactions with other traits, gender, and the environment.     

Effects of acute exercise on cardiovascular reactivity

Although exercise may modulate cardiovascular reactivity to stress, its acute effects have not been studied extensively. The purpose of this study was to examine over time the acute effects of different durations of aerobic exercise on cardiovascular reactivity to stressors. Twenty-four sedentary men underwent minimal exercise, 1 or 2 hr of stationary cycling at 55% VO _2max Heart rate, blood pressure, and blood catecholamines were measured during cold pressor, Stroop, and public speech tasks 1, 3, and 24 hr after exercise. One or two hours of exercise attenuated blood pressure responses to stress. The attenuation was evident 3 hr following exercise and was most apparent on the cold pressor task. These effects were independent of epinephrine level and stress appraisal. The role of central sympathetic processes in the effects of exercise and methodologic implications are discussed.This research was supported by research grants from the Canadian Fitness and Lifestyle Research Institute and the Heart and Stroke Foundation of Ontario to K. M. Prkachin, D. E. Mills, and H. J. Green and by a National Health Research and Development Program Fellowship to Barbara Ebbesen.     

Impact of bipolar affective disorder on family and partners

BACKGROUND: Successful management of major mental illness in the community relies significantly on an informal or non-professional network of caregivers. The needs and experiences of such caregivers have been little studied with respect to major chronic mood disorders. METHOD: A sample of caregivers (n=41) of RDC bipolar disorder was systematically interviewed to determine how this role affected them. RESULTS: Caregivers reported significant difficulties in their relationships with the patient when s/he was unwell, with considerable impact on their own employment, finances, legal matters, co-parenting and other social relationships. Violence was a particular worry for partner/parent caregivers of both male and female patients when the patient was manic. The caregiver's own mental health appeared unaffected. Despite this, the caregivers appeared emotionally committed to the patients and showed considerable tolerance of problem behaviours, which they rank-ordered for difficulty. Among nonfamily partners, knowledge of the illness before cohabitation was poor. LIMITATION: The sampling does not capture caregivers who have abandoned their role, such as spouses who have divorced the bipolar sufferer. CONCLUSIONS: Management of this illness requires a partnership between mental health professionals and the informal caregivers and the authors suggest that each group needs to understand the difficulties encountered by the other. Although erosion of relationships is a well-known complication of bipolar disorder, findings indicate that treating clinicians can rely on caregivers committed to the welfare of the patient.     

Family history of hypertension,gender, and cardiovascular reactivity and stereotypy during stress

Thirty subjects with a family history of hypertension and 28 subjects without such a history performed a Stroop Color-Word Interference task, a mental arithmetic task (serial subtraction of sevens), and a shock avoidance task (repeating digits backward while expecting to be shocked for mistakes). Systolic and diastolic blood pressure and pulse rate were recorded while subjects anticipated, undertook, and recovered from the shock avoidance task and undertook and recovered from the Stroop and mental arithmetic tasks. It was found that compared to nonfamily history subjects, family history subjects manifested reliably greater cardiovascular reactivity during each task and in anticipation of the shock avoidance task. These results are congruent with the notion that excessive sympathetic nervous system reactivity—possibly genetically determined—is involved in the development of some form(s) of essential hypertension. Further, the results indicated that family history subjects manifested greater consistency, or stereotypy, of cardiovascular response across the experimental tasks than nonfamily history subjects. The possible role of cardiovascular stereotypy in the development of essential hypertension is also discussed.This investigation was supported by University of Kansas General Research Allocation 3115-xO-0038 to B. Kent Houston.     

Plasma catecholamine and cardiovascular reactivity during an acute high ropes course event.

The primary purpose of this study was to describe physiological responses to an acute high ropes course stress. The selected dependent variables were epinephrine (E), norepinephrine (NE), heart rate (HR), systolic/diastolic blood pressure (BPs and BPd) and self-reported anxiety. A secondary purpose was to explore possible relationships between the observed physiological responses and physical fitness. College-age males were recruited for preliminary V(O(2)) max testing to identify a high-fit and low-fit subject pool. Eleven were identified as eligible participants and gave informed consent. Six participants were in the high-fit category (V(O(2)) max>60 ml/kg) and five in the low-fit category (V(O(2)) max<42 ml/kg). The Power Pole, a common high ropes course event, was selected as the acute field-based challenge activity. During participation in the challenge, a series of five (T1-T5) 10-ml blood samples were taken (via intravenous catheter) to be analyzed for E and NE. Subjective anxiety, HR, BPs and BPd were also measured at T1-T5. When the data were analyzed in a 2 (fitness group) x 5 (time) factorial ANOVA, there was a significant main effect for time with each dependent variable. However, the only difference between fitness levels was found with HR. These results indicate that the Power Pole is an acute field-based stressor for individuals of both high and low fitness levels. Due to the lack of difference between fitness groups for all variables other than HR, we conclude that participating in the Power Pole event elicits more stress of a psychosocial nature than stress of physical exertion.     

The effects of Neuroticism and Extraversion on cardiovascular reactivity during a mental and an emotional stress task

Evidence suggests that physiological reactivity to mental and emotional stress may be influenced by personality traits.ObjectivesThis study aimed to examine the relationship between, emotionally based personality traits, Neuroticism (N) and Extraversion (E), and cardiovascular reactivity (CVR) during mental arithmetic (MA) and anger recall (AR).MethodsHeart rate, blood pressure, cardiac output and total peripheral resistance were measured in 114 Singaporean male patrol officers from the Singapore Police Force while they performed MA and AR tasks. N and E were assessed using the NEO PI-R.ResultsHigher N was associated with lower DBP and TPRI reactivity during MA as compared to lower N, but higher TPRI reactivity during AR. Lower E scores were associated with heightened CVR while higher E scores were associated with lower CVR. For SBP and HR, E was associated with a reduction in reactivity across tasks; whereas, for DBP and TPRI this reduction was found only during AR.ConclusionIn this population, N had differential effects on CVR depending upon the nature of the stress task, cognitive or emotional. However, higher E was consistently linked to lower CVR during stress tasks and appeared to influence how individuals express and cope with anger.     

Neuroendocrine and cardiovascular reactivity to stress in mid-aged and older women: long-term temporal consistency of individual differences

We report long-term temporal consistency of stress-related neuroendocrine and cardiovascular variables in mid-aged and older women who performed mental math and speech stress tasks two times approximately 1 year apart. Epinephrine, norepinephrine, ACTH, cortisol, cardiac preejection period (PEP), respiratory sinus arrhythmia, heart rate (HR), blood pressure, and respiration rate were measured at baseline, after or during stressors, and 30 min posttask. Although there were exceptions, year-to-year Spearman coefficients showed mostly moderate to high consistency (rs approximately equal to .5-.8) for baseline, stressor, and posttask values. For reactivity, HR and PEP were most consistent (rs approximately equal to .65); consistency for other variables was moderate to low (rs approximately equal to .1-.4). Means of most variables changed from year to year. Results support the use of baseline, stressor, and posttask values in longitudinal studies.