Changes In Subjective Ratings Research Articles

Cochlear implant induced changes in cortical networks associated with tinnitus severity

We investigated tinnitus-related cortical networks in cochlear implant users who experience tinnitus and whose perception of tinnitus changes with use of their implant. &#xD;&#xD;Tinnitus, the perception of unwanted sounds which are not present externally, can be a debilitating condition. In individuals with cochlear implants, use of the implant is known to modulate tinnitus, often improving symptoms but worsening them in some cases. Little is known about underlying cortical changes with use of the implant, which lead to changes in tinnitus perception. In this study we investigated whether changes in brain networks with the cochlear implant turned on and off, were associated with changes in tinnitus perception, as rated subjectively.&#xD;&#xD;Approach: Using functional near-infrared spectroscopy (fNIRS), we recorded cortical activity at rest, from 14 cochlear implant users who experienced tinnitus. Recordings were performed with the cochlear implant turned off and on. For each condition, participants rated the loudness and annoyance of their tinnitus using a visual rating scale. Changes in neural synchrony have been reported in humans and animal models of tinnitus. To assess neural synchrony, functional connectivity networks with the implant turned on and off, were compared using two network features: node strength and diversity coefficient. &#xD;&#xD;Main results: Changes in subjective ratings of loudness were significantly correlated with changes in node strength, averaged across occipital channels (r=-0.65,p = 0.01). Changes in both loudness and annoyance were significantly correlated with changes in diversity coefficient averaged across all channels (r=-0.79,p<0.001 and r = -0.86,p<0.001). More distributed connectivity with the implant on, compared to implant off, was associated with a reduction in tinnitus loudness and annoyance. &#xD;&#xD;Significance: A better understanding of neural mechanisms underlying tinnitus suppression with cochlear implant use, could lead to their application as a tinnitus treatment and pave the way for effective use of other less invasive stimulation-based treatments. &#xD.

Evaluating possible ‘next day’ impairment in insomnia patients administered an oral medicinal cannabis product by night: a pilot randomized controlled trial

Cannabis and its major constituents, Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), are being widely used to treat sleep disturbances. However, THC can cause acute cognitive and psychomotor impairment and there are concerns that driving and workplace safety might be compromised the day after evening use. Here, we examined possible ‘next day’ impairment following evening administration of a typical medicinal cannabis oil in adults with insomnia disorder, compared to matched placebo. This paper describes the secondary outcomes of a larger study investigating the effects of THC/CBD on insomnia disorder. Twenty adults [16 female; mean (SD) age, 46.1 (8.6) y] with physician-diagnosed insomnia who infrequently use cannabis completed two 24 h in-laboratory visits involving acute oral administration of combined 10 mg THC and 200 mg CBD (‘THC/CBD’) or placebo in a randomised, double-blind, crossover trial design. Outcome measures included ‘next day’ (≥9 h post-treatment) performance on cognitive and psychomotor function tasks, simulated driving performance, subjective drug effects, and mood. We found no differences in ‘next day’ performance on 27 out of 28 tests of cognitive and psychomotor function and simulated driving performance relative to placebo. THC/CBD produced a small decrease (-1.4%, p=.016, d=-0.6) in accuracy on the Stroop-Colour Task (easy/congruent) but not the Stroop-Word Task (hard/incongruent). THC/CBD also produced a small increase (+8.6, p=.042, d=0.3) in self-ratings of Sedated at 10 h post-treatment, but with no accompanying changes in subjective ratings of Alert or Sleepy (p’s>0.05). In conclusion, we found a lack of notable ‘next day’ impairment to cognitive and psychomotor function and simulated driving performance following evening use of 10 mg oral THC, in combination with 200 mg CBD, in an insomnia population who infrequently use cannabis.

Stressor-Specific Sex Differences in Amygdala-Frontal Cortex Networks.

Females and males differ in stress reactivity, coping, and the prevalence rates of stress-related disorders. According to a neurocognitive framework of stress coping, the functional connectivity between the amygdala and frontal regions (including the dorsolateral prefrontal cortex (dlPFC), ventral anterior cingulate cortex (vACC), and medial prefrontal cortex (mPFC)) plays a key role in how people deal with stress. In the current study, we investigated the effects of sex and stressor type in a within-subject counterbalanced design on the resting-state functional connectivity (rsFC) of the amygdala and these frontal regions in 77 healthy participants (40 females). Both stressor types led to changes in subjective ratings, with decreasing positive affect and increasing negative affect and anger. Females showed higher amygdala-vACC and amygdala-mPFC rsFC for social exclusion than for achievement stress, and compared to males. Whereas a higher amygdala-vACC rsFC indicates the activation of emotion processing and coping, a higher amygdala-mPFC rsFC indicates feelings of reward and social gain, highlighting the positive effects of social affiliation. Thus, for females, feeling socially affiliated might be more fundamental than for males. Our data indicate interactions of sex and stressor in amygdala-frontal coupling, which translationally contributes to a better understanding of the sex differences in prevalence rates and stress coping.

On Suggestibility and Placebo: A Follow-Up Study

Identifying what makes some people respond well to placebos remains a major challenge. Here, we attempt to replicate an earlier study in which we found a relationship between hypnotic suggestibility and subjective ratings of relaxation following the ingestion of a placebo sedative (Sheiner, Lifshitz, & Raz, 2016). To assess the reliability of this effect, we tested 34 participants using a similar design. Participants ingested a placebo capsule in one of two conditions: (1) relaxation, wherein we described the capsule as a herbal sedative, or (2) control, wherein we described the capsule as inert. To index placebo response, we collected measures of blood pressure and heart rate, as well as self-report ratings of relaxation and drowsiness. Despite using a similar experimental design as in our earlier study, we were unable to replicate the correlation between hypnotic suggestibility and placebo response. Furthermore, whereas in our former experiment we observed a change in subjective ratings of relaxation but no change in physiological measures, here we found that heart rate dropped in the relaxation condition while subjective ratings remained unchanged. Even within a consistent context of relaxation, therefore, our present results indicate that placebos may induce effects that are fickle, tenuous, and unreliable. Although we had low statistical power, our findings tentatively accord with the notion that placebo response likely involves a complex, multifaceted interaction between traits, expectancies, and contexts.

Corticotropin-releasing hormone and dopamine release in healthy individuals

Corticotropin-releasing hormone (CRH) is a key component of the neuroendocrine response to stress. In animal models, CRH has been shown to modulate dopamine release, and this interaction is believed to contribute to stress-induced relapse in neuropsychiatric disorders. Here we investigated whether CRH administration induces dopamine release in humans, using positron emission tomography (PET). Eight healthy volunteers (5 female, 22–48 years old) completed two PET scans with the dopamine D2/3 receptor radioligand [11C]-(+)-PHNO: once after saline injection, and once after injection of corticorelin (synthetic human CRH). We also assessed subjective reports and measured plasma levels of endocrine hormones (adrenocorticotropic hormone and cortisol). Relative to saline, corticorelin administration decreased binding of the D2/3 PET probe [11C]-(+)-PHNO, suggesting dopamine release. Endocrine stress markers were also elevated, in line with activation of the hypothalamic-pituitary-adrenal axis, but we detected no changes in subjective ratings. Preliminary results from this proof-of-concept study suggests that CRH challenge in combination with [11C]-(+)-PHNO PET may serve as an assay of dopamine release, presenting a potential platform for evaluating CRH/dopamine interactions in neuropsychiatric disorders and CRH antagonists as potential treatment avenues.

Subjective and objective rating of spectrally different pseudorandom noises--implications for speech masking design.

Artificial sound masking is increasingly used in open-plan offices to improve speech privacy and to reduce distraction caused by speech sounds. Most of the masking sounds are based on pseudorandom continuous noise filtered to a specific spectrum that should be optimized in respect with speech masking efficiency and comfort. The aim of this study was to increase basic understanding regarding the comfort. The second aim was to determine how well objective rating methods (15 different noise indices) predict the subjective ratings. Twenty-three subjects rated the loudness, disturbance, pleasantness, and six other subjective measures of 11 spectrally different noises in laboratory conditions. Speech was not present during the experiment. All sounds were presented at 42 dB LAeq within 50-10,000 Hz. Unexpectedly, the subjects were most satisfied with sounds having emphasis on low frequencies. A sound having a slope of -7 dB per octave increment resulted in the highest satisfaction. Changes in subjective ratings were reasonably well predicted by five noise indices, while many well-known noise indices frequently used in building design underperformed in this task. The results are expected to benefit in the design of masking sounds and other appliances.

Neuropsychological changes following deep brain stimulation surgery for Parkinson's disease: comparisons of treatment at pallidal and subthalamic targets versus best medical therapy

BackgroundDeep brain stimulation (DBS) improves motor symptoms in Parkinson's disease (PD), but questions remain regarding neuropsychological decrements sometimes associated with this treatment, including rates of statistically and clinically meaningful change,...

Decreasing Nicotine Content Reduces Subjective and Physiological Effects of Smoking.

Assessment of the subjective and physiological effects of smoking cigarettes with different machine-smoked nicotine yields. Eight volunteers rated the characteristics of cigarettes with varying levels of nicotine (Quest®). At 30 minute intervals, participants smoked one of three different Quest® brand cigarettes in a counterbalanced order (reported machine-smoked nicotine yield: 0.6 mg, 0.3 mg, or 0.05 mg). Smoking satisfaction and sensations were measured on a cigarette evaluation questionnaire. A mood questionnaire measured self-reported subjective changes in 'happy', 'stimulated', 'anxious', 'desire to smoke', and 'desire not to smoke'. Heart rate and skin temperature were recorded continuously. As nicotine yield decreased, cigarettes produced smaller changes in subjective ratings on the evaluation questionnaire with the placebo nicotine cigarette always rated lower or less potent than the other two cigarettes evaluated. Heart rate was significantly increased by the reduced nicotine cigarettes, but was not affected by the nicotine-free cigarette. These results indicate that machine-smoked yield is an important determinant of both the subjective and physiological effects of smoking. The use of reduced and nicotine free cigarettes in smoking cessation programs remains to be evaluated.

Effects of different physical workload parameters on mental workload and performance

The design and evaluation of an occupational task should include an assessment of mental workload, since excessive levels of mental workload can cause errors or delayed information processing. Physically demanding work that is performed concurrently with a cognitive task may impact mental workload by impairing mental processing or decreasing performance. The primary objective of this study was to determine whether there is a differential effect of various types of physical activity on both mental workload and cognitive performance. Objective and subjective assessment tools (heart rate variability and visual analog scale) were used as indicators of mental workload, while correct responses during an arithmetic task reflected levels of performance. Thirty participants (ages 18–24 years) performed a combination of tasks inducing both physical and mental workload. Type of physical effort, frequency of movement, and force exertion level were manipulated to alter the workload associated with the physical activity. Changes in subjective ratings generally corresponded to changes in both performance on the arithmetic task and objective mental workload assessment. Some discrepancies occurred at the highest physical force exertion level as participants perceived an increase in effort to maintain the same level of performance. Further research is needed to determine the force exertion threshold, beyond which the physical effort required interferes with mental workload and/or cognitive performance. Relevance to industry Technological advancements have increased the requirement for many workers to execute cognitive tasks concurrently with physical activity. When designing and evaluating such situations it is important to determine the interactive effects of these activities. A simple, uni-dimensional tool is suggested as a screening tool to identify situations requiring excessive or increased mental workload that many degrade performance or place additional stress on the individual.

Subjective and Psychophysiological Indexes of Listening Effort in a Competing-Talker Task

The effects of noise and other competing backgrounds on speech recognition performance are well documented. There is less information, however, on listening effort and stress experienced by listeners during a speech-recognition task that requires inhibition of competing sounds. The purpose was (a) to determine if psychophysiological indexes of listening effort were more sensitive than performance measures (percentage correct) obtained near ceiling level during a competing speech task, (b) to determine the relative sensitivity of four psychophysiological measures to changes in task demand, and (c) to determine the relationships between changes in psychophysiological measures and changes in subjective ratings of stress and workload. A repeated-measures experimental design was used to examine changes in performance, psychophysiological measures, and subjective ratings in response to increasing task demand. Fifteen adults with normal hearing participated in the study. The mean age of the participants was 27 (range: 24-54). Psychophysiological recordings of heart rate, skin conductance, skin temperature, and electromyographic (EMG) activity were obtained during listening tasks of varying demand. Materials from the Dichotic Digits Test were used to modulate task demand. The three levels of task demand were single digits presented to one ear (low-demand reference condition), single digits presented simultaneously to both ears (medium demand), and a series of two digits presented simultaneously to both ears (high demand). Participants were asked to repeat all the digits they heard, while psychophysiological activity was recorded simultaneously. Subjective ratings of task load were obtained after each condition using the National Aeronautics and Space Administration Task Load Index questionnaire. Repeated-measures analyses of variance were completed for each measure using task demand and session as factors. Mean performance was higher than 96% for all listening tasks. There was no significant change in performance across listening conditions for any listener. There was, however, a significant increase in mean skin conductance and EMG activity as task demand increased. Heart rate and skin temperature did not change significantly. There was no strong association between subjective and psychophysiological measures, but all participants with mean normalized effort ratings of greater than 4.5 (i.e., effort increased by a factor of at least 4.5) showed significant changes in skin conductance. Even in the absence of substantial performance changes, listeners may experience changes in subjective and psychophysiological responses consistent with the activation of a stress response. Skin conductance appears to be the most promising measure for evaluating individual changes in psychophysiological responses during listening tasks.

Predictors of subjective ratings of stressor severity: the effects of current mood and neuroticism

AbstractRespondent‐based or subjective, ratings of stressor severity are posited to be influenced by systematic biases related to current mood and trait neuroticism which may confound associations between environmental stressors and psychological outcomes. The current study examined the effects of current mood state and neuroticism on subjective ratings of severity for real‐life stressors in a sample of 76 (30 males) undergraduates. Subjective ratings of stressor severity were collected in the context of an interview‐based stress assessment and were assessed on two separate occasions. Changes in mood state across the two assessments did not correspond with changes in subjective ratings of stressor severity. Neuroticism independently predicted subjective ratings of stressor severity, as did female gender and investigator‐based ratings of objective stressor severity. In addition, there was evidence to suggest that neuroticism fully accounted for observed associations between current mood state and subjective ratings of stressor severity. The findings are discussed with regard to the potential confounding influence of neuroticism in studies that rely on respondent‐based ratings of stressor severity in predicting psychological outcomes. Copyright © 2010 John Wiley &amp; Sons, Ltd.

Effect of the threat of a disulfiram–ethanol reaction on cue reactivity in alcoholics

Rationale Little is known about the effect of disulfiram on subjective and autonomic nervous system cue reactivity in the laboratory. The dissuasive psychological effect manifested as a threat would seem to prevail over the pharmacological effect. Objectives The primary objective was to determine whether there was a difference in cue reactivity responses during a threat condition compared to a neutral condition during alcohol cue exposure. Methods In a crossover randomized study, participants received threat and neutral messages during two cue exposure sessions. The threat condition consisted of leading the patients to believe they had ingested 500 mg of disulfiram and the neutral condition of informing them that they had ingested a placebo, while in both condition they received the same placebo. Results Physiological cue reactivity was demonstrated by a decrease in diastolic blood pressure during the threat compared to the neutral condition ( p = 0.04). Heart rate and subjective cue reactivity measures remained unchanged. There was a negative affect (assessed by the Positive and Negative Affect Scale) by condition by exposure interaction. Conclusions The threat of a disulfiram–ethanol reaction appears to affect cue reactivity physiologically rather than subjectively. While the data does not show changes in subjective ratings, it is possible that there are alternative beneficial effects arising from other cognitive processes that are not captivated by self-reported craving scales, reflected by decreases in negative affect and blood pressure. From this perspective, disulfiram might be recast to be more acceptable to patients.

Effect of Acute Antidepressant Administration on Negative Affective Bias in Depressed Patients

Acute administration of an antidepressant increases positive affective processing in healthy volunteers, an effect that may be relevant to the therapeutic actions of these medications. The authors investigated whether this effect is apparent in depressed patients early in treatment, prior to changes in mood and symptoms. In a double-blind, placebo-controlled, between-groups randomized design, the authors examined the effect of a single 4-mg dose of the norepinephrine reuptake inhibitor reboxetine on emotional processing. Thirty-three depressed patients were recruited through primary care clinics and the community and matched to 31 healthy comparison subjects. Three hours after dosing, participants were given a battery of emotional processing tasks comprising facial expression recognition, emotional categorization, and memory. Ratings of mood, anxiety, and side effects were also obtained before and after treatment. Depressed patients who received placebo showed reduced recognition of positive facial expressions, decreased speed in responding to positive self-relevant personality adjectives, and reduced memory for this positive information compared to healthy volunteers receiving placebo. However, this effect was reversed in patients who received a single dose of reboxetine, despite the absence of changes in subjective ratings of mood or anxiety. Antidepressant drug administration modulates emotional processing in depressed patients very early in treatment, before changes occur in mood and symptoms. This effect may ameliorate the negative biases in information processing that characterize mood and anxiety disorders. It also suggests a mechanism of action compatible with cognitive theories of depression.

Evaluation of a Mental Toughness Training Program for Youth-Aged Australian Footballers: I. A Quantitative Analysis

The purpose of this study was to evaluate the effectiveness of two different psychological skills training (PST) packages in enhancing mental toughness among three youth-aged (under 15 years old) Australian football teams. We compared a program targeting the keys to mental toughness identified previously (Gucciardi, Gordon, & Dimmock, 2008) with a more traditional PST program targeting self-regulation, arousal regulation, mental rehearsal, attentional control, self-efficacy, and ideal performance state as well as a control group. Overall, both intervention groups reported more positive changes in subjective ratings of mental toughness, resilience, and flow than the control group. Similar ratings for mental toughness were reported by the parents and coaches. Both PST packages appeared to be equally effective in enhancing mental toughness.

Comparison of hypopnea definitions in lean patients with known obstructive sleep apnea hypopnea syndrome (OSAHS)

In the interest of improving inter-rater reliability and standardization between sleep laboratories, hypopnea definitions were recently changed to place less emphasis on arousal scoring and more emphasis on oxygen desaturations. We sought to determine whether these changes would affect detection and treatment of OSAHS in lean patients-a group known to desaturate less-than-obese patients. Thirty-five lean subjects (15 male, 20 women, five post-menopausal) diagnosed OSAHS and a documented benefit from treatment had diagnostic polysomnograms (PSG) originally scored using the American Academy of Sleep Medicine (AASM) rule from 1999 (referred to as "Rule C"). These patients had appropriate clinical care based on those results. PSG records were then re-scored in a randomized and blinded fashion utilizing hypopnea Rule A and B of the 2007 AASM guidelines. Baseline mean (SD) apnea hypopnea indices (AHI) for rules A, B, and C were 6.4 (3.1), 20.6 (8.2), and 26.9 (7.3), respectively (p < 0.0001). Mean (SD) BMI was 24.4 (1.0). By design, all subjects were treatment responders. Eighty-six percent with CPAP, 83% with oral appliance, and 100% with surgical intervention reported resolution of their initial daytime or sleep complaint. Post-treatment AHIs for rules A, B, and C were 0.8 (0.9), 1.8 (1.2) and 2.3 (1.6; p < 0.001). In all three scoring conditions, the AHI was reduced significantly with treatment (p < 0.001). A repeated measures ANOVA of the difference between scoring methods indicated statistically significant differences between all three strategies at both pre- and post-treatment (p < 0.001). Sleepiness on the Epworth sleepiness scale decreased from a mean of 10.9 (2.3) to 5.7 (1.3) with treatment (p < 0.001). This change in subjective rating of sleepiness was more strongly correlated with rules B and C (r = 0.6) and more modestly correlated with Rule A scoring (r = 0.4). Response to treatment was more tightly correlated with arousal based scoring rules B and C in this group of lean subjects. The1999 hypopnea rule was used at baseline to detect this cohort of patients with OSAHS that ultimately benefitted from treatment. Rule B detected OSAHS and correlated well with response to treatment, but many more were categorized as mild (5 < AHI < 15) at baseline. Since 40% of the subjects had an AHI less than 5 with Rule A, lack of sensitivity should be considered before applying Rule A to the scoring of sleep studies in lean patients.

The effects of d-amphetamine on extrastriatal dopamine D2/D3 receptors: a randomized, double-blind, placebo-controlled PET study with [11C]FLB 457 in healthy subjects

The dopamine D(2)/D(3) receptor ligand [(11)C]FLB 457 and PET enable quantification of low-density extrastriatal D(2)/D(3) receptors, but it is uncertain whether [(11)C]FLB 457 can be used for measuring extrastriatal dopamine release. We studied the effects of d-amphetamine (0.3 mg/kg i.v.) on extrastriatal [(11)C]FLB 457 binding potential (BP(ND)) in a randomized, double-blind, placebo-controlled study including 24 healthy volunteers. The effects of d-amphetamine on [(11)C]FLB 457 BP(ND) and distribution volume (V(T)) in the frontal cortex were not different from those of placebo. Small decreases in [(11)C]FLB 457 BP(ND) were observed only in the posterior cingulate and hippocampus. The regional changes in [(11)C]FLB 457 BP(ND) did not correlate with d-amphetamine-induced changes in subjective ratings of euphoria. This placebo-controlled study showed that d-amphetamine does not induce marked changes in measures of extrastriatal dopamine D(2)/D(3) receptor binding. Our results indicate that [(11)C]FLB 457 PET is not a useful method for measuring extrastriatal dopamine release in humans.

Neural, electrodermal and behavioral response patterns in contingency aware and unaware subjects during a picture–picture conditioning paradigm

One way of investigating affective learning is the use of aversive pictures as unconditioned stimuli (UCS) in conditioning paradigms. In the last decades, there has been a heated debate on the influence of contingency awareness on conditioned responses (CRs). Only a few studies found CRs in contingency unaware subjects whereas other studies only reported conditioned reactions in contingency aware participants. However, as a shortcoming, most studies employing picture–picture paradigms only investigated one response level (e.g. changes in subjective ratings). Further, changes in brain activity have so far been neglected in this field of research. The aim of the present study was to investigate different response levels with respect to contingency awareness: brain activity measured by functional magnetic resonance imaging (fMRI), skin conductance responses (SCRs) and valence ratings. A neutral geometric shape (conditioned stimulus, CS+) was followed by aversive pictures, whereas another shape (CS−) preceded neutral pictures. Unaware participants showed CRs in brain activity (e.g. the insula). Generally more activity was observed in the fear network (e.g. the amygdala, the lateral orbitofrontal cortex) in aware participants and in the nucleus accumbens (NAcc). Investigation of SCRs and valence ratings revealed that only aware participants showed conditioned reactions. Our results point toward dissociations between response levels (e.g. brain activity) not affected by contingency awareness and more cognitive response levels (e.g. subjective ratings and SCRs) which are affected by contingency awareness. As a unique finding in human aversive conditioning, we discuss the role of the nucleus accumbens as well as practical implications for affective learning models.

The development of hunger and fullness during a laboratory meal in patients with binge eating disorder

This study aimed to test the hypothesis that, compared to similarly obese participants without BED, individuals with BED have a disturbance in the development of fullness and reduction of hunger during the course of a standard meal of large size. Thirteen patients with BED and 14 obese control participants consumed 975 g of a milkshake. Participants received no information about how much they had eaten or how much of the meal remained to be consumed. Participants were interrupted after every 75 g consumed to rate hunger and fullness. Final fullness ratings were higher in patients with BED, but there were no differences in mean duration or mean rate of eating, or in changes in subjective ratings of hunger and fullness per gram of food. The current study reports the surprising finding of no difference in reports of hunger and fullness between patients with BED and obese controls.

Changes in subjective ratings of impulsive steering wheel vibration due to changes in noise level: a cross-modal interaction

Cross-modal effects occur when subjective opinions of stimuli from one sense (e.g., tactile at steering wheel) are influenced by simultaneous stimuli in another sense (auditory). A steering wheel rig was used to provide specified vibration stimuli to participants' hands, and a recording of vehicle sound was played in accordance with the vibrations. Participants were subjected to test conditions with vibration values between 10 m s−2 and 20 m s−2, and auditory stimuli between 88 dB(A) and 98 dB(A) peak. Participants were neither informed of nor asked about any changes in the noise level: thus the purpose of the experiment was withheld from them. The results show that as noise level increased, subjective ratings of steering wheel vibration increased. Therefore, car cabin noise could be used to enhance the feel of the vibration at the steering wheel.

See red? Turn pale? Unveiling Emotions through Cardiovascular and Hemodynamic Changes

Cardiodynamic and hemodynamic reactions to emotion-eliciting film sequences were investigated. Thirty-two healthy subjects (12 women, 20 men) were randomly assigned to one of two groups. In the first group, anger was induced using selected scenes of the film "Ragtime." In the second group, scenes of the film "The Shining" were chosen to elicit fear. A documentary film was used as a baseline stimulus in both groups. EKG, impedance cardiography, and blood pressure were continuously monitored. The two emotional conditions elicited significant differential changes in subjective ratings and cardiovascular indices. Fear was associated with decreased cardiac output, increased total peripheral resistance, and a reduction in stroke volume and myocardial contractility. Anger was associated with an increase of cardiac output and small changes in total peripheral resistance. These results support the hypothesis that discrete emotions such as fear and anger elicit differential patterns of physiological responses.