Emotional memories: the relationship between age of memory and the corresponding psychophysiological responses.

The recollection of emotional memories has been used as a method of emotion induction for much of the research concerning the psychophysiological sequelae of emotions. The instructions used in most of these investigations have simply required the participants to recollect or imagine an emotional memory, with no constraint being placed on the age of the memory. Research has indicated that the specific instructions for inducing emotions can have a profound effect on the resulting patterns of psychophysiological arousal. The present investigation concerned whether the age of the emotional memory has an influence on the resulting psychophysiological arousal. Heart rate and skin conductance was recorded from 10 female graduate students while they recollected emotional memories concerning mirth and anger. The results indicated a significant positive correlation between skin conductance and age of both the angry (0.6395) and the mirthful (0.8460) memories. The results are discussed and explained within the framework of the somatic marker hypothesis and the spreading activation model of memories.     

Resting physiological arousal is associated with the experience of music-induced chills

In the study of emotion and autonomic nervous system functioning, resting physiological arousal is usually considered a negative characteristic. The present study examined the relationship between resting physiological arousal and positive emotional experience linked to psychophysiological arousal. We assessed resting physiological arousal using markers as high skin conductance level and low respiratory sinus arrhythmia, measured just before participants listened to their favorite music. Participants reported the sensation of chills (goose bumps, shivers) by pressing a mouse button while listening. The results indicated that individuals with resting physiological arousal frequently experience music-induced chills, which evoked unambiguous pleasurable feelings and an increase in skin conductance response. The current results, and the previously demonstrated relationship between resting physiological arousal and negative emotionality linked to psychophysiological arousal (e.g., anxiety, panic), suggest that resting physiological arousal may reflect sensitivity to psychophysiological arousal with both intense positive and negative emotions.     

Specific cue reactivity on computer game-related cues in excessive gamers

It has been posited that excessive computer game playing behavior, referred to as computer game addiction, meets criteria that have been internationally established to define drug addiction. Nevertheless, there have been no psychophysiological investigations of the underlying mechanisms available to support the characterization of excessive computer gaming as behavioral addiction. To investigate whether excessive computer gaming parallels learning processes in development and maintenance (which are assumed to underlie drug addiction), the authors obtained a psychophysiological assessment of the (learned) emotional processing of computer game-relevant and -irrelevant cues. For this purpose, electroencephalographic recordings in excessive and casual computer game players were conducted. Significant between-group differences in event-related potentials evoked by computer game related-cues were found at parietal regions and point to an increased emotional processing of these cues in excessive pathological players compared with casual players. These results are in concordance with the suggestion that addiction is characterized and maintained through sensitization of the mesolimbic dopaminergic system along with incentive salience of specific addiction-associated cues.     

Diurnal autonomic variations and emotional reactivity

Diurnal temporal variations of emotional reactivity were investigated in relationship with fluctuations of psychophysiological state, evaluated by tonic autonomic activity. Neutral and unpleasant pictures, selected to constitute seven matched sets, were evaluated by 12 participants during seven sessions in the course of daytime. Skin conductance level (SCL) was recorded at the beginning of each session, whereas skin conductance responses (SCRs), affective evaluation and emotional experience were measured during or after each session. Data show significant temporal variations for SCL, SCRs and emotional experience which follow similar patterns during the daytime. Discussion highlights the role of temporal patterns of autonomic activity as an interesting basis to better understand the emotional regulation and affective disorders.     

Psychophysiological differentiation of deception: the effects of electrodermal lability and mode of responding on skin conductance and heart rate.

The differentiation-of-deception paradigm enables the examination of deception as a psychophysiological process by varying, within subjects, two conditions which differ only with respect to honesty and deception. The present experiment assessed the effects of two group factors - electrodermal lability and mode of responding - on the deception phenomenon in a situation with low emotional involvement and mental load. Skin conductance responses, phasic heart rate, self-rated relaxation, calmness, and concentration were the dependent variables. Twenty questions referring to general knowledge were presented on a monitor. The 88 male participants answered half of the questions deceptively and the other half honestly, depending on which of two signals appeared on the screen. Half of the subjects answered verbally and the others by pressing keys. For electrodermal lability and mode of responding, significant main effects on skin conductance and heart rate were obtained. The expected main effect of truthfulness emerged in all variables, without being affected by the group factors. These findings, therefore, extend the generality and robustness of the differentiation-of-deception phenomenon.     

The time course of pupil dilation evoked by visual sexual stimuli: Exploring the underlying ANS mechanisms

The early processing of visual sexual stimuli shows signs of automaticity. Moreover, there is evidence for sex‐specific patterns in cognitive and physiological responding to erotica. However, little is known about the time course of rapid pupillary responses to sexual stimuli and their correspondence with other measures of autonomic activity in women and men. To study pupil dilation as an implicit measure of sexual arousal at various stages of picture processing, we presented 35 heterosexual participants with pictures showing either erotic couples or single (male/female) erotic nudes, contrasted with people involved in everyday situations. Brightness‐adjusted grayscale pictures were shown for a duration of 2,500 ms within the central visual field, alternating with perceptually matched patches. Left pupil diameter was recorded at 500 Hz using a video‐based eye tracker. Skin conductance and heart rate were coregistered and correlated with latent components of pupil dilation (dissociated by temporal PCA). Whereas stimulus‐evoked changes in pupil size indicated virtually no initial constriction, a rapid effect of appetence emerged (dilation to erotica within 500 ms). Responses at early stages of processing were remarkably consistent across both sexes. In contrast, later phases of pupil dilation, subjective ratings, and skin conductance responses showed a sex‐specific pattern. Moreover, evidence for an association of early‐onset pupil dilation and heart rate acceleration was found, suggestive of parasympathetic inhibition, whereas the late component was mainly related to sympathetically mediated skin conductance. Taken together, our results indicate that different temporal components of pupil responses to erotic stimuli may reflect divergent underlying neural mechanisms.     

Psychophysiological anomalies in children with emotional and conduct disorders.

We studied patterns of psychophysiological (skin conductance, heart rate) reactivity to sounds and to situations with varying emotional and alerting connotations in child psychiatric outpatients and in healthy controls. Children with emotional disorders were particularly reactive to situations with aversive components, while conduct disorder subjects showed increased reactivity to pleasant situations and decreased responses to neutral but high-intensity stimulation and to withdrawal of stimulation in silence periods. The results indicate patterns of biological reactivity which may underlie different psychiatric disturbances in children.     

Expertise in video game playing is associated with reduced valence‐concordant emotional expressivity

In carefully selected groups of video game playing (VGP) experts and nonexperts, we examined valence‐concordant emotional expressivity. We measured electromyographic (EMG) activity over the corrugator supercilii muscle while participants viewed pleasant, neutral, and unpleasant pictures. Potential group differences concerning valence‐concordant expressivity may arise from differences concerning the participants' emotional reactivity. To control for such differences, we concomitantly measured skin conductance response (SCR) and, in a separate affect misattribution procedure (AMP), valence transfer from the same set of stimuli. Importantly, we found attenuated valence‐concordant EMG activity over the corrugator supercilii muscle in VGP experts compared to nonexperts, but no differences were evident concerning SCR or valence transfer in the AMP. The findings suggest that expertise in VGP is particularly associated with reduced valence‐concordant emotional expressivity.     

All alone with sweaty palms--physiological arousal and ostracism

Social exclusion, or ostracism, is universally perceived as a negative emotional experience and often leads to poor social outcomes for individuals and society. Although the experience of distress associated with being ostracized is innate, there has been very little investigation of the effects on the autonomic nervous system. This study provides objective evidence for the effects of ostracism on arousal (examined with skin conductance levels) while participants played an internet ball-tossing game (Cyberball). Forty-two healthy undergraduate students participated in both inclusion and ostracism conditions. When participants were included, there was a marked decrement in arousal over the course of the task, whereas there was no evidence of habituation when participants were ostracized. The implications of these results are discussed in terms of the potential of differential autonomic activity to predict the coping strategies that people engage in following ostracism.     

Effects of expectancy on physiological responsivity in novice meditators

Forty non-meditators were randomly assigned to 4 experimental cells devised to control for order and expectation effects. The subjects (all female) were continuously monitored on 7 physiological measures during both meditation and rest. Each subject was her own control in an 'abab' experimental paradigm comparing meditation to rest. The subjects, meditating for the first time, showed marginally lower psychophysiological arousal during the meditation than rest condition for systolic blood pressure, heart rate, skin conductance level and digital skin temperature. Deliberately fostering positive expectations of meditation was associated with lower physiological arousal in terms of diastolic and systolic blood pressure, heart rate and skin conductance level.     

What our eyes tell us about feelings: Tracking pupillary responses during emotion regulation processes

Emotion regulation is essential for adaptive behavior and mental health. Strategies applied to alter emotions are known to differ in their impact on psychological and physiological aspects of the emotional response. However, emotion regulation outcome has primarily been assessed via self‐report, and studies comparing regulation strategies with regard to their peripheral physiological mechanisms are limited in number. In the present study, we therefore aimed to investigate the effects of different emotion regulation strategies on pupil dilation, skin conductance responses, and subjective emotional responses. Thirty healthy females were presented with negative and neutral pictures and asked to maintain or up‐ and downregulate their upcoming emotional responses through reappraisal or distraction. Pupil dilation and skin conductance responses were significantly enhanced when viewing negative relative to neutral pictures. For the pupil, this emotional arousal effect manifested specifically late during the pupillary response. In accordance with subjective ratings, increasing negative emotions through reappraisal led to the most prominent pupil size enlargements, whereas no consistent effect for downregulation was found. In contrast, early peak dilations were enhanced in all emotion regulation conditions independent of strategy. Skin conductance responses were not further modulated by emotion regulation. These results indicate that pupil diameter is modulated by emotional arousal, but is initially related to the extent of mental effort required to regulate automatic emotional responses. Our data thus provide first evidence that the pupillary response might comprise two distinct temporal components reflecting cognitive emotion regulation effort on the one hand and emotion regulation success on the other hand.     

Reduced positive emotion and underarousal are uniquely associated with subclinical depression symptoms: Evidence from psychophysiology,self‐report,and symptom clusters

Multiple models of aberrant emotional processing in depression have been advanced. However, it is unclear which of these models best applies to emotional disturbances in subclinical depressive symptoms. The current study employed a battery of psychophysiological measures and emotional ratings in a picture‐viewing paradigm to examine whether the underarousal, low positive emotion, heightened negative emotion, or emotion context insensitivity model of emotional dysfunction in subclinical depressive symptoms received greatest support. Postauricular reflex and skin conductance response potentiation for pleasant minus neutral pictures (measuring low positive emotion), overall skin conductance magnitude and late positive potential (LPP) amplitude (measuring underarousal), and pleasant minus aversive valence ratings (measuring emotion context insensitivity) and aversive minus neutral arousal ratings (measuring heightened negative emotionality) were all negatively related to depressive symptomatology. Of these, postauricular reflex potentiation and overall LPP amplitude were incrementally associated with depressive symptoms over the other measures. Postauricular reflex potentiation, overall skin conductance magnitude, and aversive minus neutral arousal ratings were incrementally associated with depressive symptomatology after controlling for other symptoms of internalizing disorders. Though no model was unequivocally superior, the low positive emotion and underarousal models received the most support from physiological measures and symptom reports, with self‐report data matching patterns consistent with the emotion context insensitivity model.     

Discovering Alzheimer's disease and bipolar disorder white matter effects building computer aided diagnostic systems on brain diffusion tensor imaging features

Responses to affective stimuli are usually studied in just one sensory system at a time. However, this is rarely the way they are experienced. We were interested in how combining affective stimuli of similar intensities across two sensory modalities (smell and vision) would affect both behavioral responses (ratings) and psychophysiological responses (skin conductance). We studied this using olfactory stimuli delivered birhinally while the subjects viewed affectively laden scenes on a computer screen. Bilateral skin conductance recordings were taken throughout. Subjects rated the pleasantness of the images that they were viewing. We found a particularly salient effect of unpleasant smells, which enhanced the pleasantness ratings of certain images and also the skin conductance responses to unpleasant images.     

Autonomic correlates of social anxiety and embarrassment in shy and non-shy individuals.

Social anxiety and embarrassment are closely related constructs, both of which are relevant to the study of shyness. To examine the psychophysiological correlates of anxiety and embarrassment in relation to shyness, we measured autonomic arousal (heart rate, respiratory sinus arrhythmia, skin conductance level, and blushing response) in shy and non-shy female participants while they performed tasks designed to elicit either social anxiety or embarrassment. Results indicated that social anxiety and embarrassment are difficult to disentangle at the autonomic level. Blushing may be an important psychophysiological marker of shyness and social anxiety.     

Up- and down-regulating facial disgust: affective, vagal, sympathetic, and respiratory consequences

Relative to watching in a natural manner, people asked to suppress or exaggerate their facial response to a negative emotional stimulus experience greater activation of the sympathetic nervous system but report a similar subjective emotional experience. The present research extends prior research on response modulation in two important ways. First, discrete indicators of cardiac vagal and sympathetic control (respiratory sinus arrhythmia (RSA) and pre-ejection period (PEP), respectively) were included as dependent measures along with interbeat interval (IBI) and skin conductance (EDR). Second, to help generalize results across response-focused modulation techniques, participants suppressed, exaggerated, or exerted no control over their responses while watching a disgust-eliciting film (for control purposes, a fourth group was asked to watch a neutral film naturally). Response modulation was associated with significantly decreased PEP (increased cardiac sympathetic control) relative to those in the natural-watch conditions. All participants evidenced increased EDR while watching the disgusting clip, but facial modulation did not produce EDR reactivity beyond that of watching the disgusting film naturally. Exaggerators experienced decreased IBI during modulation (perhaps due to increased muscle contraction) whereas all other groups showed increased IBI (i.e., the orienting response). Neither emotional experience nor facial modulation reliably impacted RSA, respiration rate, or inspiratory depth.     

Psychophysiological responses of adults who do not stutter while listening to stuttering.

The present study examined the psychophysiological responses of fluent listeners to stuttered speech. Specifically, skin conductance and heart rate changes were measured from adults who do not stutter while watching one-minute video speech samples of persons stutter read aloud. Fifteen adult participants observed three stuttered and three fluent speech samples, presented in random order with a two-minute interstimulus intervals. Results revealed that observing stuttered speech evoked a significant increase in skin conductance and a significant deceleration in heart rate relative to watching fluent speech samples. These findings suggest that listeners are physiologically aroused by stuttering and appear to maintain feelings of unpleasantness to stuttered speech. Further, deceleration in heart rate during stuttered samples also suggest that listeners may be paying more attention to the stuttered speech samples as compared to the fluent speech samples. We speculate that aberrant and anomalous stuttering behaviors probably simulate the mirror neuronal mechanism eliciting the emotional arousal associated within them. Such physiological arousal may provide the emotional genesis to the listener's negative stereotypical perceptions towards people who stutter.     

The impact of prolonged violent video‐gaming on adolescent sleep: an experimental study

Video‐gaming is an increasingly prevalent activity among children and adolescents that is known to influence several areas of emotional, cognitive and behavioural functioning. Currently there is insufficient experimental evidence about how extended video‐game play may affect adolescents' sleep. The aim of this study was to investigate the short‐term impact of adolescents' prolonged exposure to violent video‐gaming on sleep. Seventeen male adolescents (mean age = 16 ± 1 years) with no current sleep difficulties played a novel, fast‐paced, violent video‐game (50 or 150 min) before their usual bedtime on two different testing nights in a sleep laboratory. Objective (polysomnography‐measured sleep and heart rate) and subjective (single‐night sleep diary) measures were obtained to assess the arousing effects of prolonged gaming. Compared with regular gaming, prolonged gaming produced decreases in objective sleep efficiency (by 7 ± 2%, falling below 85%) and total sleep time (by 27 ± 12 min) that was contributed by a near‐moderate reduction in rapid eye movement sleep (Cohen's d = 0.48). Subjective sleep‐onset latency significantly increased by 17 ± 8 min, and there was a moderate reduction in self‐reported sleep quality after prolonged gaming (Cohen's d = 0.53). Heart rate did not differ significantly between video‐gaming conditions during pre‐sleep game‐play or the sleep‐onset phase. Results provide evidence that prolonged video‐gaming may cause clinically significant disruption to adolescent sleep, even when sleep after video‐gaming is initiated at normal bedtime. However, physiological arousal may not necessarily be the mechanism by which technology use affects sleep.     

Psychophysiological Response of Breast- and Bottle-Feeding Mothers to Their Infants'' Signals

This study examined the relationship between infant feeding status and parity of mothers, and the psychophysiological and behavioral responses of mothers to their infants' emotional signals. Forty-eight mothers (half breast-feeders, half bottle-feeders) viewed previously prepared videotaped segments of their infants' emotional expressions as heart rate, skin conductance responses, and facial expressions were monitored. Afterwards, mothers rated their subjective emotional responses to the scenes (self reports of happiness, sadness, anxiety, irritability, and helplessness) and their readiness to pick up the baby. Mothers completed an empathy measure and provided information about their choice of feeding mode and level of satisfaction with the feeding experience. The most important finding of the study was the evidence of strikingly different response patterns characterizing breast- and bottle-feeding mothers across response measures. Skin conductance measures indicated that breast-feeders may have been more relaxed under laboratory conditions than bottle-feeders; breast-feeders also showed a differential pattern of cardiac response to infant stimuli. On subjective measures of emotional response, the breast-feeders were more inclined to want interaction with the infant and they also expressed greater satisfaction with the feeding experience. Response patterns were interpreted as suggesting differential physiology of the lactating mother as well as different prior personality factors operating on choice of feeding mode. A few sex of infant and maternal parity effects were observed. Empathy and facial expression measures did not differentiate feeding or parity groups.     

Memory detection with the Concealed Information Test: A meta analysis of skin conductance,respiration, heart rate,and P300 data

The Concealed Information Test (CIT) uses psychophysiological measures to determine the presence or absence of crime‐related information in a suspect's memory. We conducted a meta‐analysis on the validity of the CIT based on four physiological measures—skin conductance response (SCR), respiration line length (RLL), changes in heart rate (HR), and enhanced amplitudes of the P300 component of the event‐related potential (P300). This meta‐analysis relied on laboratory studies that used either the mock‐crime or the personal‐item paradigm. Results showed a mean effect size (d*) of 1.55 for SCR, 1.11 for RLL, 0.89 for HR, and 1.89 for P300. However, P300 outperformed SCR only in the personal‐item paradigm, but not in the mock‐crime paradigm. Motivation level, number of questions, publication year, and the inclusion of innocent participants emerged as significant moderators for the SCR, while only the type of paradigm used moderated the P300 effect.     

Characterizing the psychophysiological signature of boredom

Research on the experience and expression of boredom is underdeveloped. The purpose of the present study was to explore the psychophysiological signature of the subjective experience of boredom. Healthy undergraduates (n = 72) viewed previously validated and standardized video clips to induce boredom, sadness, and a neutral affective state, while their heart rate (HR), skin conductance levels (SCL), and cortisol levels were measured. Boredom yielded dynamic psychophysiological responses that differed from the other emotional states. Of particular interest, the physiological signature of boredom relative to sadness was characterized by rising HR, decreased SCL, and increased cortisol levels. This pattern of results suggests that boredom may be associated with both increased arousal and difficulties with sustained attention. These findings may help to resolve divergent conceptualizations of boredom in the extant literature and, ultimately, to enhance our understanding and treatment of clinical syndromes in which self-reported boredom is a prominent symptom.