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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Bilateral experimental muscle pain changes electromyographic activity of human jaw-closing muscles during mastication

The effects of bilateral experimental muscle pain on human masticatory patterns were studied. Jaw movements and electromyographic (EMG) recordings of the jaw-closing muscles were divided into multiple single masticatory cycles and analyzed on a cycle-by-cycle basis. In ten men simultaneous bilateral injections of hypertonic saline (5%) into the masseter muscles caused strong pain (mean+/-SE: 7.5+/-0.4 on a 0-10 scale), significantly reduced EMG activity of jaw-closing muscles in the agonist phase, and significantly increased EMG activity in the antagonist phase. Nine of the subjects reported a sensation of less intense mastication during pain. Injections of isotonic saline (0.9%) did not cause pain or significant changes in masticatory patterns. The influence of higher brain centers on conscious human mastication can not be discarded but the observed phase-dependent modulation could be controlled by local neural circuits and/or a central pattern generator in the brain stem which are capable of integrating bilateral nociceptive afferent activity.     

Emotional and personality changes following cingulotomy.

The effects of bilateral anterior cingulate cortex (ACC) lesions on emotional and personality functioning were studied. Patients undergoing cingulotomy for chronic intractable pain were assessed on the MMPI, the Profile of Mood States (POMS), cognitive tests, and pain ratings, pre- and postsurgically. Patients with intractable pain, not treated with cingulotomy, served as controls. Cingulotomy patients experienced reductions in POMS–Tension, POMS–Anger, and MMPI Scale 7 (Psychasthenia) compared with baseline and the controls. POMS–Tension was significantly correlated with attention–intention performance. The results indicate that the ACC modulates emotional experience, related to self-perceived tension, and that there is a relationship between the emotional and the attentional effects of cingulotomy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Changes in torque and electromyographic activity of the quadriceps femoris muscles following isometric training

BACKGROUND AND PURPOSE: The purpose of this study was to examine the effect of isometric training of the quadriceps femoris muscles, at different joint angles, on torque production and electromyographic (EMG) activity. SUBJECTS: One hundred seven women were randomly assigned to one of four groups. Three groups trained with isometric contractions three times per week at a knee flexion angle of 30, 60, or 90 degrees. The fourth group, which served as a control, did not exercise. METHODS: Isometric torque was measured using a dynamometer, and EMG activity was measured using a multichannel EMG system. Measurements were obtained during maximal isometric contraction of the quadriceps femoris muscles at 15-degree increments from 15 to 105 degrees of knee flexion. Measurements were taken before and after 8 weeks of training. RESULTS: Following isometric exercise, increased torque and EMG activity occurred not only at the angle at which subjects exercised, but also at angles in the range of motion at which exercise did occur. Further analyses indicated that exercising in the lengthened position for the quadriceps femoris muscles (90 degrees of knee flexion) produced increased torque across all angles measured and appeared to be the more effective position for transferring strength and EMG activity to adjacent angles following isometric training as compared with the shorter positions of the muscle (30 degrees and 60 degrees of knee flexion). CONCLUSION AND DISCUSSION: These findings suggest that an efficient method for increasing isometric knee extension torque and EMG activity throughout the entire range of motion is to exercise with the quadriceps femoris muscles in the lengthened position.     

Effects of experimental manipulation of self-disclosure on group cohesiveness.

Self-disclosure in 8-hr experiential groups was systematically controlled by providing detailed audiotaped instructions and illustrations through a series of structured exercises. Two levels of self-disclosure (level of intimacy) were established. Four 8-person, heterosexually balanced groups were exposed to encounter group tapes that instructed them to share intimate feelings and experiences. Examples of high self-disclosure and openness were presented to clarify the instructions. In contrast, 4 comparable groups were conducted by encounter group tapes that furnished only moderate levels of personal disclosure and interpersonal sharing. Groups in both the high and low intimacy conditions received the same set of exercises and differed only in the instructions and accompanying behavioral examples. All Ss were undergraduates. Results indicate that higher levels of disclosure produced greater group cohesiveness as hypothesized, on 4 separate measures of the dependent variable. Findings on 3 different types of self-report instruments were corroborated by an unobtrusive behavioral measure of cohesiveness (the group hug). (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Failure of posthypnotic responding to occur outside the experimental setting.

Ten highly hypnotizable subjects and two groups of 10 nonhypnotizable simulators were formally tested for posthypnotic responding in two experimental sessions. All subjects passed at least three of the four formal tests. Between the formal test session, subjects were administered three informal tests in which the posthypnotic cue word was presented outside of the experimental context. Two of these informal tests were conducted by confederates who were unknown to any of the subjects, and the third informal test was conducted by the hypnotist. About half of the subjects in each group responded to the informal cue given by the hypnotist. However, none of the subjects in any group responded to the informal cue given by Confederate 1, and only 1 simulator and none of the high hypnotizables responded to the informal cue given by Confederate 2. These findings support the hypothesis that posthypnotic responding is expectancy-mediated, goal-directed action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Identification of emotional facial expressions following recovery from depression.

This study investigated the identification of facial expressions of emotion in currently nondepressed participants who had a history of recurrent depressive episodes (recurrent major depression; RMD) and never-depressed control participants (CTL). Following a negative mood induction, participants were presented with faces whose expressions slowly changed from neutral to full intensity. Identification of facial expressions was measured by the intensity of the expression at which participants could accurately identify whether faces expressed happiness, sadness, or anger. There were no group differences in the identification of sad or angry expressions. Compared with CTL participants, however, RMD participants required significantly greater emotional intensity in the faces to correctly identify happy expressions. These results indicate that biases in the processing of emotional facial expressions are evident even after individuals have recovered from a depressive episode. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibition of masseteric electromyographic activity during oral respiration

Although the effects of oral respiration on the growth and development of craniofacial structure have been studied previously, little is known about how altered respiration affects the activity of the jaw-closing muscles. Obstruction of the nasal airway in the cat significantly inhibited the masseteric stretch reflex and discharges of masseteric motor units but did not affect the electromyographic activity of the diaphragm. This inhibition was greater during inspiration than during expiration. In addition, the amplitude of the masseteric monosynaptic reflex elicited by electrical stimulation of the mesencephalic trigeminal nucleus showed no significant change in association with the altered respiratory mode. These findings suggest that masseteric electromyographic activity is inhibited during oral respiration and that the gamma-system is involved in this inhibition.     

Context extinction following conditioning with delayed reward enhances subsequent instrumental responding.

In Experiment 1, delayed reward generated low response rates relative to immediate reward delivered with the same frequency. Lister rats exposed to delayed reward subsequently responded at a higher rate in extinction if they received nonreinforced exposure to the conditioned context after instrumental training and prior to test, compared with animals that received home cage exposure. In Experiment 2, a signaled delay of reinforcement resulted in higher rates than an unsignaled delay. Nonreinforced exposure to the conditioning context elevated response rate for subjects in the unsignaled condition relative to a home cage group, but had no effect on response rates for subjects that had received the signaled delay. In Experiment 3, following an unsignaled reinforcement delay, groups receiving either no event or signaled food in the context responded faster in extinction than groups receiving no context exposure or unsignaled food. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prevention of microstomia following facial burns

A polymorphic dinucleotide (CA) repeat sequence was isolated from a genomic clone containing the human calcitonin gene at 11p15.2-p15.1. This polymorphism will be a useful marker in the genetic study of disorders affecting calcium metabolism including hyperparathyroidism, hypoparathyroidism, and osteoporosis.     

Verbal pragmatics following unilateral stroke: Emotional content and valence.

Verbal pragmatic aspects of discourse production were examined in 16 right brain-damaged (RBD), 16 left brain-damaged (LBD), and 16 normal control right-handed adults. The facilitation effect of emotional content, valence hypothesis, and relationship between pragmatics and emotion were evaluated. Participants produced monologues while recollecting emotional and nonemotional experiences. Transcribed monologues were rated for appropriateness on 6 pragmatic features: conciseness, lexical selection, quantity, relevancy, specificity, and topic maintenance. Overall, brain-damaged groups were rated as significantly less appropriate than normals. Consistent with the facilitation effect, emotional content enhanced pragmatic performance of LBD aphasic participants yet suppressed performance of RBD participants. Contrary to the valence hypothesis, RBD participants were more impaired for positive emotions and LBD participants for negative emotions. Pragmatic appropriateness was not strongly correlated with a measure of emotional intensity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Looking happy: The experimental manipulation of a positive visual attention bias.

Individuals with a positive visual attention bias may use their gaze to regulate their emotions while under stress. The current study experimentally trained differential biases in participants' (N = 55) attention toward positive or neutral information. In each training trial, one positive and one neutral word were presented and then a visual target appeared consistently in the location of the positive or neutral words. Participants were instructed to make a simple perceptual discrimination response to the target. Immediately before and after attentional training, participants were exposed to a stress task consisting of viewing a series of extremely negative images while having their eyes tracked. Visual fixation time to negative images, assessed with an eye tracker, served as an indicator of using gaze to successfully regulate emotion. Those participants experimentally trained to selectively attend to affectively positive information looked significantly less at the negative images in the visual stress task following the attentional training, thus demonstrating a learned aversion to negative stimuli. Participants trained toward neutral information did not show this biased gaze pattern. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Emotional and cardiovascular sensitization to daily stress following childhood parental loss.

Adverse childhood events can influence the development of emotional and physiological self-regulatory abilities, with significant consequences for vulnerability to psychological and physical illness. This study evaluated stress sensitization and inoculation models of the impact of early parental death on stress exposure and reactivity in late adolescence/young adulthood. Ambulatory blood pressure (BP) and diary reports of minor stress were collected every 30 min during waking hours over a 24-hr period from 91 late adolescents/young adults (43 early bereaved, 48 nonbereaved). Across the sample, minor stressors were associated with elevated BP and negative affect. The bereaved group had lower BP than did the nonbereaved group. Within the bereaved group, higher perceived caring from the surviving parent was associated with fewer reports of minor stress and lower stress-related negative affect. Higher perceived parental caring during childhood was associated with lower BP across the sample and more frequent hassles in the nonbereaved group. Findings support both the stress inoculation and sensitization models, suggesting that childhood parental loss and parental caring exert important influences on children's development of stress sensitivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recognition of facial stimuli following an intervening task involving the Identi-kit.

The Identi-kit is a tool for constructing a facial composite. The types of errors made on a recognition task, following an intervening task involving the Identi-kit, were examined in this study. One hundred and eight introductory psychology students viewed a target composite-face and made an Identi-kit reconstruction. Subsequently, they were required to identify the original composite-face from a lineup of six composite-faces. Subjects who made an Identi-kit reconstruction were prone to make more errors on the recognition task than participants in a control condition, p?p?p?     

Specific changes in conditioned responding following neurotoxic damage to the posterior parietal cortex.

The central nucleus (CN) of the amygdala and basal forebrain cholinergic projections to the posterior parietal cortex (PPC) are involved in regulating changes in attentional processing of conditioned stimuli. In a previous study, lesions of the CN produced a deficit in conditioned orienting behavior (rearing on the hind legs) when a visual stimulus was paired with food. Unconditioned orienting (rearing to nonreinforced presentations of the stimulus) and conditioned food cup behavior were unaffected. The present study examined the contribution of the PPC to attentional orienting behavior. Damage to the PPC did not affect orienting behavior but produced deficits in food cup behavior. These findings help define the specific contributions of the PPC to attentional processing and associative learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Altered responding to cholecystokinins and dopaminergic agonists following 6-hydroxydopamine treatment in rats.

In 5 experiments with 265 male Wistar albino rats, production of lesions in the brain dopamine (DA) system by intraventricular injection of 6-hydroxydopamine (6-OHDA) resulted in increased responses to subcutaneous apomorphine (0.5 mg/kg) and reduced responses to methamphetamine (0.15 mg/kg). It also made Ss increase responding to intracerebroventricular (icv) cholecystokinin octapeptide (CCK-8; 0.5–2 μg) and reduce responding to cholecystokinin tetrapeptide (CCK-4; 0.5–2 μg). Response changes were quantified by measuring the level of general activity. Results indicate that DA dysfunction not only affected DA receptor sensitivity but also the sensitivity of the CCK system. The response to CCK-8 was partially blocked by a selective CCK-8 antagonist, proglumide (5 μg, icv), a result suggesting the involvement of the CCK-8 receptor system. Results indicate that manipulation of 1 neuronal system could induce sensitivity changes in another closely related system. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Instrumental response persistence following induction of hippocampal theta frequency during fixed-ratio responding in rats.

Four groups of 6 male albino rats (24 Ss) were used to investigate the relationship between hippocampal theta and instrumental response persistence. All Ss were first trained on a discrete-trial FR-10 schedule of reinforcement. In Phase 2, hippocampal theta was induced via electrical stimulation of medial septal pacemaker cells through implanted electrodes at the beginning of 50% of the 8 daily FR-10 trials for experimental Ss, while stimulated-control Ss received 200-Hz medial septal stimulation which does not induce theta. The 2 remaining control groups continued as in the training phase. In Phase 3, FR-10 responding was extinguished in all Ss. Induction of hippocampal theta depressed responding and led to greater resistance to extinction in the experimental group compared with the other groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An experimental manipulation of Rorschach form: The effect of making indistinct the ambiguous.

Systematic variations of the stimulus properties of the Rorschach inkblots are relatively rare. In this study, form was altered by projecting slides of the blots out of focus. Since this blurring more or less duplicated the situation to be expected in some types of poor vision, there are practical implications; to make the application to the clinic as direct as possible within the limitations of the experimental design, the degree of blurring was adjusted to that associated with a commonly encountered level of defective eyesight. In an otherwise standard group-administration procedure, every other slide was presented out of focus, the even numbered to 1 group of 20 Ss, the odd to another. Marked changes occurred in location, P, F%, F + %, and other, nonform determinants. The magnitude and importance of these changes lead to the caution that the Rorschach might well be preceded by a test of visual acuity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)