Masked affective stimuli moderate task difficulty effects on effort-related cardiovascular response

This experiment investigated the combined effect of masked affective stimuli and task difficulty on effort-related cardiovascular response. Cardiovascular reactivity (ICG, blood pressure) was recorded during a baseline period and performance of an easy or difficult attention task in which participants were exposed to masked sad vs. happy facial expressions. As expected, participants in the sad-faces/easy and happy-faces/difficult conditions showed stronger sympathetic nervous system discharge to the heart and vasculature--shorter preejection period, higher systolic blood pressure--indicating more effort than participants in the sad-faces/difficult and happy-faces/easy conditions. Total peripheral resistance reacted similarly as preejection period and systolic blood pressure. The findings are compatible with the effects of consciously experienced affect on effort-related cardiovascular response.     

Beyond valence: the differential effect of masked anger and sadness stimuli on effort-related cardiac response

This experiment investigated the moderating effect of masked anger versus sadness primes on objective task difficulty's impact on effort-related cardiovascular response. Cardiovascular measures (ICG and blood pressure) were assessed during a habituation period and an easy versus difficult short-term memory task during which participants were exposed to masked emotional facial expressions. As expected, sadness primes led to stronger cardiac preejection period (PEP) responses than anger primes when the task was easy. When the task was difficult, we observed the reversed pattern. Here, anger primes led to stronger PEP reactivity than sadness primes. Heart rate responses described the corresponding pattern. The results demonstrate that masked anger and sadness primes have different effects on cardiac response in easy and difficult tasks. The effect of anger primes resembles the facilitating effect of happiness primes observed in previous studies.     

Mirrors, masks, and motivation: Implicit and explicit self-focused attention influence effort-related cardiovascular reactivity

Using motivational intensity theory as a framework, three experiments examined how implicit self-focus (manipulated with masked first-name priming) and explicit self-focus (manipulated with a large mirror) influence effort-related cardiovascular activity, particularly systolic blood pressure reactivity. Theories of self-focused attention suggest that both implicit and explicit self-focus bring about self-evaluation and thus make meeting a goal more important. For a "do your best" task of unfixed difficulty, implicit and explicit self-focus both increased effort (Experiment 1) compared to a control condition. For a task that varied in difficulty, implicit and explicit self-focus promoted more effort as the task became increasingly hard (Experiments 2 and 3). Taken together, the findings suggest that implicit and explicit self-processes share a similar motivational architecture. The discussion explores the value of integrating motivational intensity theory with self-awareness theory and considers the emerging interest in implicit aspects of effort regulation.     

Mood impact on effort-related cardiovascular reactivity depends on task context: Evidence from a task with an unfixed performance standard

Gendolla and colleagues have consistently found that negative mood leads to higher effort-related cardiovascular reactivity than positive mood if performers can choose their own performance standard (Gendolla et al., 2001; Gendolla and Krüsken, 2001a, 2002a,b). However, an integration of motivational intensity theory with the mood literature suggests that the impact of mood on cardiovascular activity should vary with task context. In a 2 (task context: demand vs. reward) × 2 (mood valence: negative vs. positive) between-persons design, participants performed a memory task without a fixed performance standard. The results showed the expected interaction. Positive mood led to higher effort mobilization—reflected by increased pre-ejection period and heart rate reactivity—than negative mood if participants had answered questions about task reward before performing the task. If participants had responded to questions about task demand, the pattern was reversed. These results extend and add to preceding research that has demonstrated that mood impact on effort-related cardiovascular activity is not stable but depends on task context.     

Incentive moderates the impact of implicit anger vs. sadness cues on effort-related cardiac response

This experiment investigated the combined effect of implicit affect and monetary success incentive on effort-related cardiac response in a 2 (Affect Prime: anger vs. sadness)×2 (Incentive: low vs. high) between-person design. Sixty-two participants were exposed to affect primes during an objectively difficult short-term memory task. As predicted, by our theorizing about affect primes' systematic impact on subjectively experienced task demand and corresponding effort mobilization, sadness primes led to a weak cardiac pre-ejection period (PEP) response when incentive was low (disengagement), but to a very strong PEP response when incentive was high (high effort). PEP responses were moderate in the anger-prime conditions (low effort). HR responses largely corresponded to those of PEP. The results demonstrate for the first time that high incentive can compensate the effort mobilization deficit of individuals who process sadness primes during a difficult task.     

The joint effect of mood, task valence, and task difficulty on effort-related cardiovascular response and facial EMG

This study investigated whether a pleasant task with high potential for mood regulation could eliminate the motivational deficit of people facing a difficult task in a negative mood. Cardiovascular and facial EMG reactivity of 88 University students were measured during habituation, mood inductions, and an either pleasant or unpleasant scenario completion task that was either easy or difficult. In the unpleasant condition cardiovascular reactivity was modest, particularly in the negative-mood/difficult condition. But when the task was pleasant, cardiovascular reactivity in the negative-mood/difficult condition was stronger than in all other conditions, reflecting the elimination of the motivational deficit. Moreover, facial EMG reactivity indicated efficient mood manipulations. In summary, the findings are interpreted as further support for the mood-behavior-model [Gendolla, G.H.E., 2000. On the impact of mood on behavior: an integrative theory and a review. Rev. Gen. Psychol. 4, 378–408].     

Mood-regulative hedonic incentive interacts with mood and task difficulty to determine effort-related cardiovascular response and facial EMG

Based on the mood–behavior-model [Gendolla, G.H.E., 2000. On the impact of mood on behavior: an integrative theory and a review. Review of General Psychology, 4, 378–408], we investigated the joint effect of mood-regulative hedonic incentive, mood states, and task difficulty on effort-related cardiovascular response. Cardiovascular and facial EMG reactivity of 80 participants were assessed during a baseline period, mood inductions, and an either easy or difficult memory task with either pleasant or unpleasant consequences of success. For unpleasant consequences, we anticipated that mood would interact with task difficulty to determine cardiovascular response: relatively high reactivity under negative-mood/easy and positive-mood/difficult conditions and relatively low reactivity under positive-mood/easy and negative-mood/difficult conditions. In contrast, we expected for pleasant consequences an increase of cardiovascular response in the negative-mood/difficult condition because here mood-regulative incentive justified the high effort required by a difficult task in a negative mood. Results were generally as expected and facial EMG reactivity indicated efficient mood manipulations. In summary, the findings further support the predictions of the mood–behavior-model.     

Self-focus and task difficulty effects on effort-related cardiovascular reactivity

Two experiments examined the joint impact of self-focused attention and task difficulty on performance-related cardiovascular reactivity. Predictions were derived from an application of the principles of motivational intensity theory and its integration with the active coping approach to performance conditions that have consequences for self-esteem. According to this model, self-focus will induce a state of self-evaluation and thus augment the importance of success, and cardiovascular reactivity will increase with difficulty until a task becomes impossible or the goal is not worth the necessary resources. Supporting these predictions, 2 experiments found that high self-focus increased performance-related systolic blood pressure reactivity when difficulty was unfixed ("do your best") or fixed at a high level. When the task was easy or impossible, however, high self-focus did not affect systolic reactivity relative to low self-focus.     

Mental fatigue influence on effort-related cardiovascular response: Extension across the regulatory (inhibitory)/non-regulatory performance dimension

Participants first performed a scanning task that was weak (fatigue low) or strong (fatigue high) in self-regulatory (inhibitory) demand. They then were presented a cognitive challenge that had a strong regulatory component (the Stroop color-word conflict task) or a weak regulatory component (single-digit mental multiplication) with instructions that they would avoid noise if they attained a moderate performance standard. Analysis of cardiovascular data collected during the two work periods revealed fatigue main effects for systolic blood pressure, diastolic blood pressure, and mean arterial blood pressure. The effects reflected stronger blood pressure responses for High Fatigue participants across work periods and regardless of the character of the challenge presented in work period 2. Results conceptually replicate previous mental fatigue findings, which have shown extension of fatigue influence across cognitive performance domains. At least as importantly, they also extend those findings by showing extension across a fresh and theoretically significant cognitive performance dimension.     

Long-lasting effect of subliminal processes on cardiovascular responses and performance

Students were exposed to a priming task in which subliminal representations of the goal of studying were directly paired (priming-positive group) or not (priming group) to positive words. A control group without subliminal prime of the goal was added. Just after the priming task, students performed an easy or a difficult learning task based on their coursework. Participants in the priming-positive group performed better and had a stronger decrease of pulse transit time and pulse wave amplitude reactivity than participants of the two other groups, but only during the difficult condition. Results suggested that subliminal priming induces effortful behavior extending over twenty five minutes but only when the primes had been associated with visible positive words acting as a reward. These findings provide evidence that subliminal priming can have long-lasting effects on behaviors typical of daily life.     

The effects of achievement motivation, task difficulty, and goal difficulty on physiological, behavioral, and subjective effort

The purpose of the study was to present experimental arguments evaluating the Humphreys and Revelle's model of effort. Two important factors were tested: achievement motivation and difficulty. Heart rate, heart rate variability, blood pressure, facial electromyographic reactivity, and reaction time were measured as an index of effort expenditure. A 2 × 2 × 2 factorial design was used with two levels of resultant achievement motivation, two levels of task difficulty, and two levels of goal difficulty. As expected, the 16 participants high in resultant achievement motivation showed a better performance and had a larger decrease of the midfrequency band than the 16 participants low in resultant achievement motivation, especially during the difficult task. Results lend some support for the impact of resultant achievement motivation, task difficulty, and goal difficulty on effort mobilization.     

Cardiovascular reactivity and adaptation to recurrent psychological stress: effects of prior task exposure.

The effects of prior task exposure on cardiovascular reactivity to stress were examined in two experiments by randomly assigning participants to repeated exposure groups that performed mental arithmetic pretest and test tasks versus delayed exposure groups that performed only the test task after prolonged rest. Impedance cardiographic and blood pressure measures were recorded continuously from 60 undergraduate men in Experiment 1 and 112 undergraduate men and women in Experiment 2. Task repetition attenuated cardiovascular reactivity and improved task performance in repeated exposure groups (p < .001), suggesting an integrated process of behavioral adaptation. During the test task, delayed exposure groups showed greater cardiac reactivity (p < .01), but not vascular reactivity, than repeated exposure groups. Thus, cardiac reactivity varied as a specific function of prior task exposure, whereas vascular reactivity varied as a general function of time.     

Nicotine and acute stress: effects of nicotine versus nicotine withdrawal on stress-induced hemoconcentration and cardiovascular reactivity

This study was designed to assess the effects of nicotine and nicotine withdrawal on stress-induced hemoconcentration and cardiovascular reactivity during acute stress in smokers. Forty-six smokers (>or=10 cigarettes per day) were tested twice, once while wearing a 21 mg nicotine patch for 12h and once while wearing a placebo patch (nicotine withdrawal). Calculated plasma volume, hemoglobin, hematocrit, HR, SBP, DBP, cardiac output, stroke volume, and total peripheral resistance were assessed during a 10-min baseline period, 6-min Paced Auditory Serial-Addition Task (PASAT), and a 2-min cold pressor (CP). No differences between conditions were found for any of the hematological measurements. Participants demonstrated greater HR and SBP increases to the PASAT during the nicotine withdrawal condition. For CP, participants showed greater HR and DBP increases and SV decreases during the nicotine withdrawal condition. Data from affective state ratings indicated that participants reported more negative affect during the psychological challenges during nicotine withdrawal conditions. Negative affective state may further lead to enhanced cardiovascular reactivity. These results demonstrate that although nicotine and nicotine withdrawal significantly have differential effects on cardiovascular functioning, the same differential condition effects do not appear to exist for stress-induced hemoconcentration.     

Cardiovascular reactivity and adaptation to recurrent psychological stress: the moderating effects of evaluative observation

The impact of evaluative observation on cardiovascular reactivity and adaptation to recurrent psychological stress was evaluated in 162 undergraduate men and women. All participants performed three mental arithmetic tasks with or without evaluative observation. Impedance cardiographic, blood pressure, task performance, and stress appraisal measures were recorded for each task. Evaluative observation moderated the effects of task repetition on cardiac reactivity but not vascular reactivity. The introduction of evaluative observation disrupted cardiac adaptation, resulting in a resurgence of beta-adrenergic cardiac reactivity (p < .005), whereas the removal of evaluative observation promoted cardiac adaptation. Evaluative observation also increased stress appraisals and slowed task performance. The results support the dual process theory of habituation, rather than stimulus comparator theory, but only partially support cognitive appraisal theory.     

When fatigue promotes striving: Confirmation that success importance moderates resource depletion influence on effort-related cardiovascular response

Undergraduate volunteers performed an easy (fatigue low) or difficult (fatigue high) counting task and then were presented a difficult scanning task with instructions that the task was or was not diagnostic of an important ability (low versus high ego-involvement, respectively). As expected, systolic blood pressure responses in the second work period were positively proportional to fatigue where ego-involvement (and, thus, success importance) was high, but not where ego-involvement (and, thus, importance) was low. The pressure findings provide fresh support for the suggestion of a recent fatigue analysis that importance should moderate fatigue influence on effort-related CV responses to a performance challenge so long as fatigued performers view success as possible, conceptually replicating and extending effects from a previous fatigue experiment.     

Social stressors and cardiovascular response: Influence of ambivalent relationships and behavioral ambivalence

Objective

The protective influence of social relationships on health is well documented; however, not all relationships are positive and negative aspects of relationships may be detrimental. Relatively less is known about the relationships characterized by both positivity and negativity (i.e., ambivalence). The goal of this study was to examine the relative influence of ambivalence in relationship quality and social behavior on cardiovascular response.

Methods

104 healthy young adults were randomly assigned to bring in either a supportive or ambivalent same-sex friend to the experiment. Participants were also randomly assigned to receive positive, negative, ambivalent or ambiguous feedback from their friend after giving a series of speeches. Cardiovascular response was obtained before, during, and after the social stressor (speech task).

Results

Results indicate a significant effect of relationship type before, during, and after the stressor task. Adjusting for baseline, heart rate reactivity and anxiety was significantly higher among those assigned to ambivalent friends relative to those assigned to supportive friends during the stressor task (ps < .05). There was also a significant effect of behavioral feedback during the speech task, such that those receiving ambivalent messages had the greatest systolic blood pressure (SBP) and diastolic blood pressure (DBP) reactivity (p < .05); however, there was no interaction between relationship and feedback conditions. Those in the ambivalent friend condition also exhibited significantly higher SBP, DBP, and anxiety during the baseline and recovery periods (ps < .05).

Conclusions

These findings suggest that both relationship quality and the actions of relationships may have a significant influence on health-relevant physiology.     

Outcome expectancy as a moderator of mental fatigue influence on cardiovascular response

Female undergraduates performed an easy (fatigue low) or difficult (fatigue high) scanning task and then were presented mental arithmetic problems with instructions that they would earn a high or low chance of winning a prize if they did as well as or better than 50% of those who had performed previously. As expected, blood pressure responses in the second work period rose or tended to rise with fatigue where the chance of winning was high. By contrast, the responses tended weakly to decline with fatigue where the chance of winning was low. The pressure findings support the suggestion of a recent fatigue analysis that success importance should moderate fatigue influence on CV responses to a challenge so long as fatigued performers view success as possible. They also conceptually replicate previous fatigue results and provide a special class of evidence that fatigue influence on CV response is mediated by effort.     

The effects of an acute psychological stressor on cardiovascular, endocrine, and cellular immune response: A prospective study of individuals high and low in heart rate reactivity

High and low reactors were preselected on the basis of their heart rate reactivity to a speech stressor in a prescreening session. In the main study, subjects were exposed to a mental arithmetic plus noise stressor. Cardiovascular activity was recorded during baseline and stressor, and blood was drawn prior to and following the stressor for endocrine and immune assays. Results revealed that the stressor decreased the blastogenic response to concanavalin A and increased natural killer cell numbers and cytotoxicity, absolute numbers of CD8⁺ T-lymphocytes, nor-epinephrine and epinephrine levels, heart rate, and blood pressure responses. In addition, cortisol and natural killer cell cytotoxicity responses to the stressor differentiated individuals high versus low in heart rate reactivity. These results suggest that the interactions among the autonomic nervous system, endocrine system, and immune system are not only amenable to psychophysiological analysis but that such analyses may play an important role in illuminating underlying mechanisms.     

The effects of depressive symptoms on cardiovascular and catecholamine responses to the induction of depressive mood

We examined the effects of depressive symptoms on cardiovascular and catecholamine responses to the induction of different mood states. Fifty-five healthy men and women (mean age 23.4 +/- 3 years) were recruited. Depressive symptoms were evaluated using the Center for Epidemiological Studies Depression Scale (CES-D) and participants were classified into high depressive (CES-D*16) or low depressive symptoms (CES-D < 16) groups. Following a baseline period, participants were required to complete two separate speech tasks where they were asked to recall life events that made them feel angry or depressed. The tasks were separated by a 30-min recovery period and the order was randomised between participants using a counterbalanced design. Cardiovascular function was monitored continuously using a Finometer device and saliva was collected for the assessment of 3-methoxy-phenylglycol (MHPG, the major metabolite of norephinephrine). Blood pressure (BP), heart rate, and total peripheral resistance (TPR) were significantly increased in response to both tasks (p = .001). Averaged over conditions, higher diastolic BP and higher MHPG levels were observed in high depressive symptoms participants. MHPG levels did not change in response to mood induction in the low depressive symptoms group. However, the high depression symptoms group showed significantly higher levels of MHPG during recovery from the depressed mood induction task and increased levels immediately after the anger induction task. These findings suggest depressive symptoms are associated with heightened central adrenergic activation during negative mood induction, but that the time course of responses is dependent on the type of emotion elicited.     

Gender determination of effort and associated cardiovascular responses: when men place greater value on available performance incentives

Participants were presented an easy or difficult mental addition task and led to believe that they could win a traditionally masculine incentive by meeting a certain performance standard. As expected, blood pressure and heart rate responses during the work period were stronger under difficult conditions than easy ones among men but low under both difficulty conditions among women. Findings support the suggestion from a conceptual analysis grounded in motivation intensity theory that gender differences in cardiovascular response could be partially understood in terms of effort processes that occur where men and women place different value on available performance incentives.