The role of muscle tension in “repression”

Using an active partial avoidance conditioning paradigm, muscle tension was conditioned to a verbal conditional stimulus (CS), and recall of words semantically unrelated and related to the CS was tested under conditions of three levels of induced muscle tension with 20 subjects (Ss). Results showed the expected decrease in latency of response with moderate tension for all stimuli during the pretreatment period and for the unrelated words during the posttreatment period and a significant increase in latency of response for the related words during the posttreatment period. It is suggested that if the level of muscle tension associated with the conditional response (CR) is induced in Ss, then recall of CS-related material will be inhibited or “repressed.”     

Verbal, Facial and Autonomic Responses to Empathy-Eliciting Film Clips by Disruptive Male Adolescents with High Versus Low Callous-Unemotional Traits

This study examined empathy-related responding in male adolescents with disruptive behavior disorder (DBD), high or low on callous-unemotional (CU) traits. Facial electromyographic (EMG) and heart rate (HR) responses were monitored during exposure to empathy-inducing film clips portraying sadness, anger or happiness. Self-reports were assessed afterward. In agreement with expectations, DBD adolescents with high CU traits showed significantly lower levels of empathic sadness than healthy controls across all response systems. Between DBD subgroups significant differences emerged at the level of autonomic (not verbal or facial) reactions to sadness, with high CU respondents showing less HR change from baseline than low CU respondents. The study also examined basal patterns of autonomic function. Resting HR was not different between groups, but resting respiratory sinus arrhythmia (RSA) was significantly lower in DBD adolescents with high CU traits compared to controls. Results support the notion that CU traits designate a distinct subgroup of DBD individuals.     

Insular activity during passive viewing of aversive stimuli reflects individual differences in state negative affect

People differ with regard to how they perceive, experience, and express negative affect. While trait negative affect reflects a stable, sustained personality trait, state negative affect represents a stimulus limited and temporally acute emotion. So far, little is known about the neural systems mediating the relationship between negative affect and acute emotion processing. To address this issue we investigated in a healthy female sample how individual differences in state negative affect are reflected in changes in blood oxygen level-dependent responses during passive viewing of emotional stimuli. To assess autonomic arousal we simultaneously recorded changes in skin conductance level. At the psychophysiological level we found increased skin conductance level in response to aversive relative to neutral pictures. However, there was no association of state negative affect with skin conductance level. At the neural level we found that high state negative affect was associated with increased left insular activity during passive viewing of aversive stimuli. The insula has been implicated in interoceptive processes and in the integration of sensory, visceral, and affective information thus contributing to subjective emotional experience. Greater recruitment of the insula in response to aversive relative to neutral stimuli in subjects with high state negative affect may represent increased processing of salient aversive stimuli.     

The effects of anxiety upon attention allocation to affective stimuli

Pictures of emotionally aversive, neutral, and pleasant scenes were presented for 500 ms, followed by a probe presented in the same location (valid trials) or an alternate location (invalid trials) as the picture. Response-times to the probes were recorded in low (N=20) and high (N=27) trait anxious participants. Results revealed an overall negative cue validity effect of shorter reaction times (RTs) on invalid than valid trials, suggestive of an inhibition of return effect. Moreover, high trait anxious females showed a reduced negative cue validity effect for aversive pictures in comparison with neutral and pleasant pictures, suggestive of selective interference by the unpleasant material. By contrast, low trait anxious females showed an enhanced negative cue validity effect for aversive pictures relative to neutral and pleasant pictures, suggestive of attentional avoidance of the aversive content. The emotional content of picture cues did not significantly affect RTs in males, regardless of anxiety status. The results suggest that biased attention processes for aversive stimuli may contribute to the greater female propensity for anxiety disorders.     

The EMG gradient as a reflection of metamotivational state

The significance of motivational statedominance in everyday life and actual motivational state during task performance was investigated in relation to skeletal muscle tension patterns during performance in the continuous preceptual-motor task paradigm. Subjects were recruited to form seriousminded (telic) and playful (paratelic) extreme groups according to their responses to the Telic Dominance Scale (6 subjects in each group). They all performed a continuous perceptual-motor task twice in a neutral context (N1, N2), once with threat of aversive shock at poor performance (T), and once with promise of monetary reward for good performance (R); T and R being balanced around N 2. Measures of tonic (slow) EMG activation were derived from the "passive" forearm, and structured (blind) interview assessed motivational state. It was concluded that motivational state, rather than statedominance, was associated with EMG activation. The telic state was significant to high EMG activation for the N I and T treatments in particular.     

Self‐Report and Psychophysiological Responses to Fear Appeals

This study was designed to assess the relationship between self‐report and psychophysiological responses to fear appeals and behavioral changes elicited by these. Ninety‐two subjects watched one of four messages that varied in level of threat (high vs. low) and efficacy (high vs. low). Concomitantly, psychophysiological measures (heart rate and skin conductance) were registered. Perceived threat and efficacy varied according to the characteristics of the message. High‐threat messages elicited significantly different levels of autonomic arousal than low‐threat messages. Following of behavioral recommendation was higher among subjects who were exposed to the high threat / high efficacy stimulus, those who reported high perceived threat, and for those who showed an autonomic response pattern related to the facilitation of attentional processes.     

The lasting effect of words on feelings: words may facilitate exposure effects to threatening images

Previous studies have shown that mere words, particularly affective words, can dampen emotional responses. However, the effect of affective labels on emotional responding in the long term is unknown. The authors examined whether repeated exposure to aversive images would lead to more reduction in autonomic reactivity a week later if the images were exposed with single-word labels than without labels. In Experiment 1, healthy individuals were exposed to pictures of disturbing scenes with or without labels on Day 1. On Day 8, the same pictures from the previous week were exposed, this time without labels. In Experiment 2, participants were spider fearful and were exposed to pictures of spiders. In both experiments, although repeated exposure to aversive images (without labels) led to long-term attenuation of autonomic reactivity, exposure plus affective labels, but not nonaffective labels, led to more attenuation than exposure alone. Thus, affective labels may help dampen emotional reactivity in both the short and long terms. Implications for exposure therapy and translational studies are discussed.     

Effects of alcohol on psychophysiological hyperreactivity to nonaversive and aversive stimuli in men at high risk for alcoholism

Psychophysiological reactivity to nonaversive (1-KHz, 70-db tones) and aversive stimuli (shock) was examined in nonalcoholic men with multigenerational family histories (MFH) of alcoholism and family history negative (FH-) men, while sober and after consuming alcohol. In comparison with FH- Ss, sober MFH Ss had significantly larger skin conductance (SC) orienting responses (ORs), shorter OR latencies, slower habituation rates to the tones, and larger increases in heart rate and vasoconstriction to the shock. Alcohol dampened the magnitude of the SC-OR to the tones and the degree of cardiovascular reactivity to the shocks and increased the habituation rate to the tones in MFH Ss only. Alcohol consumption also increased the SC-OR recovery time in FH- Ss only. The MFH Ss' pattern of psychophysiological hyperreactivity is discussed in terms of a potential dysfunction in stimulus-response regulation.     

The impact of perceived self-efficacy on memory for aversive experiences

Self-efficacy is a key construct underlying healthy functioning and emotional well-being. Perceptions of uncontrollability, unpredictability, and low self-efficacy are consistently associated with negative mental health outcomes, such as post-traumatic stress disorder (PTSD). To test the causal relation between perceived coping self-efficacy and stress responses we employed a trauma film paradigm in which college students (N=33) viewed a graphic film of the aftermath of a motor vehicle accident following a high (HSE) or low self-efficacy (LSE) induction. Participants were tested for intrusions, distress, and memory recall for the film over the following 24 hours. LSE participants recalled more central details than HSE participants. Further, HSE participants reported fewer negative intrusions immediately following the film and at 24 hours. These findings suggest that strategies that increase perceived coping self-efficacy may reduce intrusive recollections of an aversive event, and also reduce the attentional bias associated with remembering aversive stimuli.     

Emotional catharsis and aggression revisited: heart rate reduction following aggressive responding

The authors tested two components of the catharsis theory of aggression: physiological tension reduction and aggressive drive reduction. On the basis of work in the stress-aggression literature, they also examined the moderating effect of impersonal stress exposure on cathartic reductions in heart rate following aggressive responding. Participants were instructed to administer nonaggressive (correct button) or aggressive (shock button) responses to a frustrating confederate in a laboratory aggression paradigm, and half the participants were exposed to an impersonal stressor (aversive air blasts) during the procedure. Heart rate was recorded before and after the participants administered the aggressive or nonaggressive response. Analyses revealed that participants exhibited reductions in heart rate following aggressive but not nonaggressive responding, but this was the case only for those not exposed to the impersonal stressor. Heart rate reductions during the experimental blocks actually predicted the most intense aggression in a subsequent block of trials. The results are considered in light of different theories of aggression by J. E. Hokanson (1974) and L. Berkowitz (1990) and have implications for interventions with anger-prone individuals.     

BIS and BAS correlates with psychophysiological and cortical response systems during aversive and appetitive emotional stimuli processing

The present research intended first to confirm psychophysiological and cortical responses to valence- and arousal-manipulated stimuli and second to show how the BIS and BAS (Behavioural Inhibition and Activation System) personality characteristics correlated with these psychophysiological and cortical responses. Multiple measures were recorded, such as psychophysiological (skin conductance response, heart rate, and electromyography) and ERPs (event-related potentials) responses, during viewing IAPS figures, that varied in terms of pleasantness (appetitive vs. aversive) and arousing power (high vs. low intensity). Autonomic variables and two ERP positive deflections (P3 and LPP ERP effects) were found to be modulated by valence and arousal rating, with an increased response for high arousing and negative or positive stimuli in comparison with low arousing and neutral stimuli. Moreover, high BAS subjects were more responsive to positive than negative emotions, whereas high BIS subjects responded in greater measure to negative and arousing emotions. Findings were discussed in light of biphasic model of emotion comprehension.     

Types of Aggression,Responsiveness to Provocation,and Callous-unemotional Traits in Detained Adolescents

The present study investigated differences in the behavioral and psychophysiological responses to provocation and in the level of callous-unemotional traits in boys exhibiting different patterns of aggression. Eighty-five boys (ages 13-18) in a juvenile detention center played a competitive computer task against a hypothetical peer who provided low and high levels of provocation. Youth high on both self-reported reactive and proactive aggression showed different behavioral responses to provocation than youth high on only reactive aggression. Specifically, the combined group showed high levels of aggressive responses without any provocation, whereas the group high on reactive aggression showed an increase in aggressive responding to low provocation. Further, results revealed a trend for the combined group to show lower levels of skin conductance reactivity to low provocation if they were also high on callous-unemotional traits.     

Eye fixations in prediction of recognition and recall

Eye fixations were recorded at viewing of picture-label stimuli presented under either recall or recognition instructions; both retention tests were administered. Ss performed substantially better on the retention test of which they were informed, indicating differential encoding of the same stimuli in anticipation of test type. There was no correlation between recognition and recall of items, evidence that different information from the encoded stimuli was utilized in performing each test. Encoding strategies had no effect on how Ss regarded the stimuli, but viewing patterns were related to memory performance: More word fixations was associated with better verbal recall, while fewer picture fixations was associated with better recall and with better picture recognition.     

Biofeedback-assisted relaxation in the control of reactions to a challenging task and anxiety-provoking film

This experiment was designed to evaluate the use of a combined relaxation- and biofeed-back-training procedure in the regulation of psychophysiological reactivity to laboratory stressors. Twenty volunteers participated in the 3-session experiment, comparing relaxation plus skin conductance biofeedback (Training) with simple instructions to relax (Control). During Session 1. subjects tried to solve a series of visual puzzles and watched an anxiety-provoking film, and were then assigned to treatments on the basis of electrodermal reactions to the film. The relaxation methods were practised in Sessions 2 and 3. and were followed by a second film excerpt and series of tasks. Heart rate (HR), skin conductance level (SCL) and ratings of tension and relaxation were recorded throughout.No differences in physiological or self-report variables emerged during quiet relaxation. However, during the post-treatment administration of Stressors, SCL was augmented in the Control group, while remaining near pre-treatment values in the Training condition. This effect was confined to SCL, since HR and self-reported tension did not distinguish the groups post-treatment.     

Arousal of negative emotions and symptom-specific reactivity in chronic low back pain patients

Anger may have greater effects on chronic pain severity than other negative emotions and may do so by increasing muscle tension near the site of injury (symptom-specific reactivity). For patients with chronic low back pain (CLBP), relevant muscles are lower paraspinals (LP). Ninety-four CLBP patients and 79 controls underwent anger and sadness recall interviews. EMG and cardiovascular activity were recorded. Patients exhibited greater LP tension increases during anger and slower recovery than controls. Only patients showed greater LP reactivity during anger than sadness. For both groups, trapezius reactivity during anger and sadness did not differ. LP reactivity to anger correlated with everyday pain severity for patients. Anger-induced symptom-specific LP reactivity may be linked to chronic pain aggravation among CLBP patients.     

Effects of sexual versus fear arousal on alcohol consumption in college males

To compare the effects of pleasant and aversive arousal on alcohol consumption, 18 male undergraduates had three weekly sessions to separately view erotic, mutilation or neutral slides in a simulated memory experiment. Following exposure to the slides, they received access to alcoholic and nonalcoholic beverages, which were presented to half the subjects in a taste rating task, and to half as the result of engaging in an operant lever-press task. Subjects believed these tasks to be distractors during a purported retention interval. Self-report instruments and basal skin conductance confirmed the success of the affective manipulations. However, only the subjects using the taste task after viewing erotic slides significantly increased alcohol consumption. These results question a tension reduction model of drinking and qualify the contribution of autonomic arousal to motivation for drinking.     

Operant GSR conditioning with cool air reinforcement

Two groups of 20 Ss each were run individually in a soundproof chamber heated to 115 F and humidified to 100%. Ss in the experimental group received brief presentation of cool air contingent upon emitted GSRs during 20 min of acquisition. Control Ss were matched one at a time in operant rate and were yoked one at a time to receive the cool air on a response-independent schedule. Both groups increased significantly in rate of unelicited GSRs during acquisition, with the experimental Ss’ curve rising more rapidly and both groups attaining equivalent terminal levels. During extinction, the groups maintained high levels of responding and did not differ. Examination of basal skin conductance data ruled out an activation hypothesis. In the control Ss, terminal response frequency was significantly correlated with percentage of fortuitous response-contingent reinforcement. It was concluded that both groups were conditioned, with the controls receiving intermittent reinforcement sufficiently often to elevate their responding. The cool air was judged to be an effective reinforcer of unelicited GSRs, perhaps more effective than those used in previous studies.     

Differential payoff and locus of selectivity in a visual memory task

Two experiments were run to investigate the locus of selectivity in a visual memory task involving differential payoff for letters correctly recalled: Major variables consisted of value instructions given before or after the exposure of a display, the ratio of high to low value, and exposure duration. The results showed that Ss make more correct reports of higher value than of lesser value, whether value instructions are given before or after the display. Furthermore, overall performance and extent of selectivity increase with increasing exposure time, but more for the before than the after conditions of instruction. These results suggest that selectivity occurs both during perception and retention and during recall.     

Personality and conditioning with appetitive and aversive stimuli

Two studies examining relationships of extraversion (E), neuroticism (N) and psychoticism (P) to conditioning performance are reported. In the first, 31 male volunteers developed electrodermal CRs to appetitive or aversive stimuli of either weak or strong rated intensity. Factor analysis yielded general factors of classical CR acquisition and extinction across reinforcement type. Stability and E loaded the acquisition factor, these Ss, from post-hoc analysis, revealing superior conditioning in the strong appetitive condition. In the second study, 20 of these 31 Ss participated in two series of discrimination motor reaction time trials, in which attainment of criterion RT was reinforced by appetitive slides, and slower-than-criterion responding by aversive slides. Introversion was correlated with greater response acquisition under both conditions, although post-hoc analysis suggested that improvement under positive reinforcement did not differ from simple practice. Results are congruent with a model combining reinforcer preference with response potential to describe personality-conditioning relationships.