Nicholas Christenfeld

Physiological stress reactivity and recovery: Conceptual siblings separated at birth?

This article discusses theoretical assumptions underlying physiological stress reactivity research. It examines early conceptualizations of activation and recovery and contrasts these with current practices in designing, analyzing, and reporting stress reactivity studies. Study protocols from four major journals covering the last 2 years of publication were examined for current practices. Of the 105 studies which tested physiological reactivity, 63% collected recovery data but only 23% reported the recovery data. We concluded that stress recovery issues are neglected and a renewed case is made for their conceptual and ecological importance. The case for studying recovery is further supported by a selective review of studies using recovery protocols that revealed positive findings not apparent in reactivity comparisons only. Finally, options for sound design of recovery protocols, statistical processing of resulting data, and interpretation of findings are presented.

Toward a causal model of cardiovascular responses to stress and the development of cardiovascular disease

Objective Cardiovascular reactivity is hypothesized to mediate the relationship between stress and cardiovascular disease. We describe three considerations that are crucial for a causal model of cardiovascular responses to stress: the need for laboratory-life generalizability, the role of interactions between environmental exposures and individual response predispositions, and the importance of the duration of both stressor exposure and cardiovascular responding. Methods We illustrate current understanding of stress–cardiovascular disease relationships with examples from the human and animal psychophysiology, epidemiology, and genetics literature. Results In a causal model of reactivity, the usefulness of laboratory assessment rests on the assumption that laboratory-based cardiovascular reactivity predicts responses in the natural environment. We find only limited generalizability and suggest that cardiovascular responses to stress can be better understood when examined in the natural environment. The interaction of individual response predispositions and stressor exposures contributes to the development and progression of cardiovascular disease; stress-disease relationships could therefore be better understood if predispositions and exposures were assessed simultaneously in interactive models. Cardiovascular responses to stress are likely to be most deleterious when responses are prolonged. Responses may vary in their magnitude, frequency, and duration; however, reactivity captures only response magnitude. The assessment of anticipatory and recovery measures, with response magnitude, may therefore lead to a more useful model of the stress-disease relationship. Conclusions A causal model of cardiovascular responses to stress should generalize to the real world, assess interactions between individual predispositions and environmental exposures, and focus on sustained pathogenic exposures and responses.

The role of rumination in recovery from reactivity: cardiovascular consequences of emotional states.

Objective While most investigations of the link between blood pressure responses and later disease have focused on acute reactivity during stressful tasks, there is some theoretical and empirical reason to believe that examining recovery and later re-creations of BP responses may also be useful. Two experiments explored situational determinants of sustained BP elevations, examining whether the extent of recovery and the ability to later mentally recreate the response are influenced by the magnitude or emotionality of the initial task and also whether preventing rumination after a stressor has ended speeds recovery. Method Experiment 1, with 72 normotensive male and female undergraduates, examined BP and heart rate before, during, and after a task and also before, during, and after the mental re-creation of that task. Four tasks were used, designed to produce high initial reactivity with an emotional component (mental arithmetic with harassment), low reactivity with emotion (shock avoidance), high reactivity without emotion (physical exercise), or low reactivity without emotion (cold pressor). Experiment 2, with 20 normotensive male and female undergraduates, compared the cardiovascular recovery of persons who were either given a distractor task or just sat quietly immediately after a mental arithmetic task. Results Study 1 revealed that only the emotional tasks were associated with delayed BP recovery and elevations during later rumination. Blood pressure during recovery and later rumination was independent of the original reactivity. Experiment 2 found that participants with the distractor, who presumably could not ruminate, showed better BP recovery. Conclusions Situations that put people at risk may include not just those that cause large BP elevations, but also emotion-producing situations that lead to sustained and recurring elevations.

The Role of Angry Rumination and Distraction in Blood Pressure Recovery From Emotional Arousal

Objective: Cardiovascular recovery of prestress baseline blood pressure has been implicated as a possible additional determinant of sustained blood pressure elevation. We hypothesize that angry ruminations may slow the recovery process. Method: A within-subjects design was used in which resting baseline blood pressure and heart rate measurements were assessed on 60 subjects, who then took part in two anger-recall tasks. After each task, subjects sat quietly and alone during a 12-minute recovery period randomized to with or without distractions. During baseline, task, and recovery, blood pressure was continuously monitored; during recovery, subjects reported their thoughts at five fixed intervals. Results: Fewer angry thoughts were reported in the distraction condition (17%) compared with no distraction (31%; p = .002); an interaction showed that this effect was largely the result of the two intervals immediately after the anger-recall task. Trait rumination interacted with distraction condition such that high ruminators in the no-distraction condition evidenced the poorest blood pressure recovery, assessed as area under the curve (p = .044 [systolic blood pressure] and p = .046 [diastolic pressure]). Conclusions: People who have a tendency to ruminate about past anger-provoking events may be at greater risk for target organ damage as a result of sustained blood pressure elevations; the effect is exacerbated when distractions are not available to interrupt the ruminative process. ANOVA = analysis of variance; AUC = area under the curve; BP = blood pressure; HTN = hypertension; CHD = coronary heart disease; CVR = cardiovascular reactivity; CVD = cardiovascular disease; HR = heart rate; DAB-VR = Destructive Anger Behavior-Verbal Rumination; DBP = diastolic BP; HPA = hypothalamic-pituitary-adrenal; SBP = systolic BP.

Gender, social support, and cardiovascular responses to stress.

OBJECTIVE Laboratory research indicates that the presence of a supportive other can reduce physiological responses to a stressor. Whether there are gender differences, either on the part of the provider or the recipient, in this social support effect is explored. Such differences might shed some light on the frequent epidemiological reports of gender differences in social support and health. METHODS Male and female subjects gave an impromptu speech and received either standardized supportive or nonsupportive feedback from a male or female confederate. Blood pressure and heart rate were monitored continuously during baseline and speech periods. RESULTS Speakers with a supportive female audience showed a systolic increase of 25 mm Hg over baseline. Those with a nonsupportive female audience increased 36 mm Hg. A supportive male audience led to increases of 32 mm Hg, and a nonsupportive male audience 28 mm Hg. There was no significant effect of gender of subject. CONCLUSIONS Results indicate that social support provided by women reduced cardiovascular changes for both male and female speakers compared with presence of a nonsupportive female audience. Social support from men did not. These findings suggest a possible mechanism that might help explain the epidemiological literature on the relationship between gender, social support, and health. The findings are consistent with the notion that married men are healthier because they marry women. Women do not profit as much from marriage or suffer as much from separation, in terms of health outcomes, because the support they gain or lose is the less effective support of a man. These findings render more plausible the possibility that differences in social support might contribute to health differences, through the dampening of cardiovascular responses to stress.

Gender, Jealousy, and Reason

Research has suggested that men are especially bothered by evidence of their partners sexual infidelity, whereas women are troubled more by evidence of emotional infidelity One evolutionary account (Buss, Larsen, Westen, & Semmelroth, 1992) argues that this is an innate difference, arising from mens need for paternity certainty and womens need for male investment in their offspring We suggest that the difference may instead be based on reasonable differences between the sexes in how they interpret evidence of infidelity A man, thinking that women have sex only when in love, has reason to believe that if his mate has sex with another man, she is in love with that other A woman, thinking that men can have sex without love, should still be bothered by sexual infidelity, but less so because it does not imply that her mate has fallen in love as well A survey of 137 subjects confirmed that men and women do differ in the predicted direction in how much they think each form of infidelity implies the other, proposing innate emotional differences may, therefore, be gratuitous

Choices from Identical Options

Many of the decisions that people must make involve selections from arrays of identical options The six studies presented explored peoples preferences in two contexts choosing one item from rows of identical items and choosing a route from a series of identical routes The first three studies examined preferences for items in particular positions Whether people were choosing a product from a grocery shelf, deciding which bathroom stall to use, or marking a box on a questionnaire, they avoided the ends and tended to make their selection from the middle For example, when there were four rows of a product in the supermarket, only 29% of the purchases were from the first and last rows, and 71% were from the middle two The last three studies examined whether a similar preference exists in picking a route when all of the available routes are the same length and require the same number of turns In solving mazes, planning routes on maps, and walking around campus, people showed the pattern opposite to that found for choosing items in rows They avoided the middle routes and tended to take either the first or the last one Overall, the last available route was the favorite The notion that these behaviors may minimize mental effort is explored

An Increase in the Number of Deaths in the United States in the First Week of the Month — An Association with Substance Abuse and Other Causes of Death

BACKGROUND AND METHODS There are regular changes in mortality rates, such as increased rates of death from influenza in the winter and from motor vehicle accidents on long holiday weekends. Previous research has shown that among persons with schizophrenia, the rates of cocaine use and hospital admissions increase at the beginning of the month, after the receipt of disability payments. Using computerized data from all death certificates in the United States between 1973 and 1988, we compared the number of deaths in the first week of the month with the number of deaths in the last week of the preceding month. RESULTS The average number of deaths was about 5500 per day, or about 165,000 in a 30-day month. There were 100.9 deaths (95 percent confidence interval, 100.8 to 101.0) in the first week of the month for every 100 deaths in the last week of the preceding month. This was equivalent to about 4320 more deaths in the first week of each month than in the last week of the preceding month in an average year. Between 1983 and 1988, for deaths involving substance abuse and an external cause (such as suicides, accidents, and homicides), there were 114.2 deaths (95 percent confidence interval, 110.5 to 117.9) in the first week of the month for every 100 in the last week of the preceding month. There were significant increases in the number of deaths in the first week of the month for many causes of death, including substance abuse, natural causes, homicides, suicides, and motor vehicle accidents. CONCLUSIONS In the United States, the number of deaths is higher in the first week of the month than in the last week of the preceding month. The increase at the beginning of the month is associated with substance abuse and other causes of death.

Underestimating the Duration of Future Events: Memory Incorrectly Used or Memory Bias?

People frequently underestimate how long it will take them to complete a task. The prevailing view is that during the prediction process, people incorrectly use their memories of how long similar tasks have taken in the past because they take an overly optimistic outlook. A variety of evidence is reviewed in this article that points to a different, although not mutually exclusive, explanation: People base predictions of future duration on their memories of how long past events have taken, but these memories are systematic underestimates of past duration. People appear to underestimate future event duration because they underestimate past event duration.

Music can facilitate blood pressure recovery from stress

OBJECTIVES Interventions that reduce the magnitude of cardiovascular responses to stress are justified, at least in part, by the notion that exaggerated responses to stress can damage the cardiovascular system. Recent data suggest that it is worthwhile to explore, in addition to the magnitude of the cardiovascular responses during stress (reactivity), the factors that affect the return to baseline levels after the stressor has ended (recovery). This experiment examined the effect of listening to music on cardiovascular recovery. DESIGN AND METHOD Participants (N = 75) performed a challenging three-minute mental arithmetic task and then were assigned randomly to sit in silence or to listen to one of several styles of music: classical, jazz or pop. RESULTS Participants who listened to classical music had significantly lower post-task systolic blood pressure levels (M = 2.1 mmHg above pre-stress baseline) than did participants who heard no music (M = 10.8 mmHg). Other musical styles did not produce significantly better recovery than silence. CONCLUSIONS The data suggest that listening to music may serve to improve cardiovascular recovery from stress, although not all music selections are effective.