Diurnal autonomic variations and emotional reactivity

Effectiveness of labels in digital art experience: psychophysiological and behavioral evidence

Introduction

Nowadays museums make large use of digital materials (e.g., virtual tours) to attract visitors. Therefore, it is worthwhile investigating which variables affect the engagement with art outside the museum, and whether digital reproductions of artworks are as effective as museum originals in producing a satisfying aesthetic experience.

Methods

Here we tested the effectiveness of introducing additional informative materials on the artistic enjoyment of contemporary paintings presented on a computer screen. Naïve observers were exposed to essential and descriptive labels before viewing artworks. We flanked traditional measurement methods - viewing times and questionnaires, with biometric parameters - pupil responses, eye movements, heart rate, and electrodermal activity. The results were then compared to our previous museum study that adopted the same experimental paradigm.

Results

Our behavioral and psychophysiological data lead to a complex pattern of results. As found in the museum setting, providing detailed descriptions decreases complexity, evokes more positive sensations, and induces pupil dilation but does not enhance aesthetic appreciation. These results suggested that informative labels improve understanding and emotions but have a limited impact on the hedonic evaluation of artworks in both contexts. However, other results do not mirror those found in the museum; in the laboratory setting, participants spend a similar amount of time, have a comparable gaze behavior, and their electrodermal activity and heart rate do not change when viewing artworks with different types of labels. The main difference between the lab and museum settings is the shorter time spent viewing digital reproductions vs. real paintings, although subjective ratings (e.g., liking, interest) are comparable.

Discussion

Overall, this study indicates that the environmental context does impact the aesthetic experience; although, some beneficial effects of introducing additional relevant content in labels accompanying artworks can also be acquainted through digital media outside of the museum.

Circadian-like patterns in electrochemical skin conductance measured from home-based devices: a retrospective study

In this study, we investigated the potential of electrochemical skin conductance (ESC) measurements gathered from home-based devices to detect circadian-like patterns. We analyzed data from 43,284 individuals using the Withings Body Comp or Body Scan scales, which provide ESC measurements. Our results highlighted a circadian pattern of ESC values across different age groups and countries. Our findings suggest that home-based ESC measurements could be used to evaluate circadian rhythm disorders associated with neuropathies and contribute to a better understanding of their pathophysiology. However, further controlled studies are needed to confirm these results. This study highlights the potential of digital health devices to generate new scientific and medical knowledge.

Enhancing precision in human neuroscience

Human neuroscience has always been pushing the boundary of what is measurable. During the last decade, concerns about statistical power and replicability - in science in general, but also specifically in human neuroscience - have fueled an extensive debate. One important insight from this discourse is the need for larger samples, which naturally increases statistical power. An alternative is to increase the precision of measurements, which is the focus of this review. This option is often overlooked, even though statistical power benefits from increasing precision as much as from increasing sample size. Nonetheless, precision has always been at the heart of good scientific practice in human neuroscience, with researchers relying on lab traditions or rules of thumb to ensure sufficient precision for their studies. In this review, we encourage a more systematic approach to precision. We start by introducing measurement precision and its importance for well-powered studies in human neuroscience. Then, determinants for precision in a range of neuroscientific methods (MRI, M/EEG, EDA, Eye-Tracking, and Endocrinology) are elaborated. We end by discussing how a more systematic evaluation of precision and the application of respective insights can lead to an increase in reproducibility in human neuroscience.

Psychophysiological and behavioral responses to descriptive labels in modern art museums

Educational tools in art exhibitions seem crucial to improve the cultural and aesthetic experience, particularly of non-expert visitors, thus becoming a strategic goal for museums. However, there has not been much research regarding the impact of labels on the quality of visitors' aesthetic experience. Therefore, here we compared the impact on the cognitive and emotional experience of naïve visitors between essential and descriptive labels, through multiple objective and subjective measurements, focusing on the controversial modern art museum context. We found that, after detailed descriptions, observers spend more time inspecting artworks, their eyes wander more looking for the described elements, their skin conductance and pupil size increase, and overall, they find the content less complex and more arousing. Our findings show that people do receive important benefits from reading detailed information about artworks. This suggests that elaborating effective labels should be a primary goal for museums interested in attracting a non-expert public.

Preferential consolidation of emotional reactivity during sleep: A systematic review and meta-analysis

Many studies have investigated whether sleep affects cognitively unmodulated reactivity to emotional stimuli. These studies operationalize emotion regulation by using subjective and/or objective measures to compare pre- and post-sleep reactivity to the same emotional stimuli. Findings have been inconsistent: some show that sleep attenuates emotional reactivity, whereas others report enhanced or maintained reactivity. Across-study methodological differences may account for discrepant findings. To resolve the questions of whether sleep leads to the attenuation, enhancement, or maintenance of emotional reactivity, and under which experimental conditions particular effects are observed, we undertook a synthesized narrative and meta-analytic approach. We searched PubMed, PsycINFO, PsycARTICLES, Web of Science, and Cochrane Library databases for relevant articles, using search terms determined a priori and search limits of language = English, participants = human, and dates = January 2006–June 2021. Our final sample included 24 studies that investigated changes in emotional reactivity in response to negatively and/or positively valenced material compared to neutral material over a period of sleep compared to a matched period of waking. Primary analyses used random effects modeling to investigate whether sleep preferentially modulates reactivity in response to emotional stimuli; secondary analyses examined potential moderators of the effect. Results showed that sleep (or equivalent periods of wakefulness) did not significantly affect psychophysiological measures of reactivity to negative or neutral stimuli. However, self-reported arousal ratings of negative stimuli were significantly increased post-sleep but not post-waking. Sub-group analyses indicated that (a) sleep-deprived participants, compared to those who slept or who experienced daytime waking, reacted more strongly and negatively in response to positive stimuli; (b) nap-exposed participants, compared to those who remained awake or who slept a full night, rated negative pictures less negatively; and (c) participants who did not obtain substantial REM sleep, compared to those who did and those exposed to waking conditions, had attenuated reactivity to neutral stimuli. We conclude that sleep may affect emotional reactivity, but that studies need more consistency in methodology, commitment to collecting both psychophysiological and self-report measures, and should report REM sleep parameters. Using these methodological principles would promote a better understanding of under which conditions particular effects are observed.

Take my advice: Physiological measures reveal that intrinsic emotion regulation is more effective under external guidance

Research into emotion regulation (ER) has focused primarily on the intra-personal process through which we regulate our own emotions intrinsically. More recently, however, studies have begun to explore the inter-personal nature of intrinsic ER - that is, how we regulate our emotions under the guidance of others. Preliminary evidence suggests that ER might be more effective when implemented in an inter- compared with an intra-personal manner, but these findings are based almost exclusively on self-reported ratings that capture only the subjective experience of emotions. The current study therefore investigated whether this apparent superiority of inter-personal intrinsic ER could be replicated and extended to physiological measures of affective reactions - namely, various metrics of electrodermal activity. In a within-subjects design, a sufficiently powered sample (N = 146) were required to down-regulate their emotional reactions to negatively valenced images using an ER strategy they had chosen themselves intra-personally or one that had been recommended to them inter-personally. Physiological responses converged to demonstrate the greater effectiveness of inter- over intra-personal ER in decreasing negative affective reactions, despite subjective ratings suggesting that participants perceived the opposite to be true. The superiority of inter- over intra-personal ER in physiological recordings was unrelated to individuals' perceptions of their ability to regulate their own emotions, however, and so it remains to be seen if and how such benefits extend to clinical populations.

Associations of sleep measures with neural activations accompanying fear conditioning and extinction learning and memory in trauma-exposed individuals

STUDY OBJECTIVES

Sleep disturbances increase risk of posttraumatic stress disorder (PTSD). Sleep effects on extinction may contribute to such risk. Neural activations to fear extinction were examined in trauma-exposed participants and associated with sleep variables.

METHODS

Individuals trauma-exposed within the past 2 years (N = 126, 63 PTSD) completed 2 weeks actigraphy and sleep diaries, three nights ambulatory polysomnography and a 2-day fMRI protocol with Fear-Conditioning, Extinction-Learning and, 24 h later, Extinction-Recall phases. Activations within the anterior cerebrum and regions of interest (ROI) were examined within the total, PTSD-diagnosed and trauma-exposed control (TEC) groups. Sleep variables were used to predict activations within groups and among total participants. Family wise error was controlled at p < 0.05 using nonparametric analysis with 5,000 permutations.

RESULTS

Initially, Fear Conditioning activated broad subcortical and cortical anterior-cerebral regions. Within-group analyses showed: (1) by end of Fear Conditioning activations decreased in TEC but not PTSD; (2) across Extinction Learning, TEC activated medial prefrontal areas associated with emotion regulation whereas PTSD did not; (3) beginning Extinction Recall, PTSD activated this emotion-regulatory region whereas TEC did not. However, the only between-group contrast reaching significance was greater activation of a hippocampal ROI in TEC at Extinction Recall. A greater number of sleep variables were associated with cortical activations in separate groups versus the entire sample and in PTSD versus TEC.

CONCLUSIONS

PTSD nonsignificantly delayed extinction learning relative to TEC possibly increasing vulnerability to pathological anxiety. The influence of sleep integrity on brain responses to threat and extinction may be greater in more symptomatic individuals.

Quantifying Occupational Stress in Intensive Care Unit Nurses: An Applied Naturalistic Study of Correlations Among Stress, Heart Rate, Electrodermal Activity, and Skin Temperature

OBJECTIVE

To identify physiological correlates to stress in intensive care unit nurses.

BACKGROUND

Most research on stress correlates are done in laboratory environments; naturalistic investigation of stress remains a general gap.

METHOD

Electrodermal activity, heart rate, and skin temperatures were recorded continuously for 12-hr nursing shifts (23 participants) using a wrist-worn wearable technology (Empatica E4).

RESULTS

Positive correlations included stress and heart rate (ρ = .35, p < .001), stress and skin temperature (ρ = .49, p < .05), and heart rate and skin temperatures (ρ = .54, p = .0008).

DISCUSSION

The presence and direction of some correlations found in this study differ from those anticipated from prior literature, illustrating the importance of complementing laboratory research with naturalistic studies. Further work is warranted to recognize nursing activities associated with a high level of stress and the underlying reasons associated with changes in physiological responses.

APPLICATION

Heart rate and skin temperature may be used for real-time detection of stress, but more work is needed to validate such surrogate measures.

Psychophysiological dynamics of emotional reactivity: Interindividual reactivity characterization and prediction by a machine learning approach

The fast reaction of the autonomic nervous system (ANS) to an emotional challenge (EC) is the result of a functional coupling between parasympathetic (PNS) and sympathetic (SNS) branches. This coupling can be characterized by measures of cross-correlations between electrodermal activity (EDA) (under the influence of the SNS) and the RR interval (the interval between R peaks) (under the influence of the PNS and the SNS). Significant interindividual variability has previously been reported in SNS-PNS coupling in emotional situations, and the present study aimed to identify interindividual cross-correlation variability in ANS reactivity. We therefore studied EDA and the RR interval in 62 healthy subjects, recorded during a 24-minute EC. A Gaussian Mixture Model was used to cluster tonic EDA-RR cross-correlations during the EC. This identified two clusters that were characterized by significant or non-significant cross-correlations (SCC and NCC clusters, respectively). The SCC cluster reported higher negative emotion after the EC, while the NCC cluster reported higher scores on the Center for Epidemiologic Studies-Depression scale. The latter finding suggests that NCC is a pathological mood pattern with altered negative perception. Furthermore, a machine learning model that included three parameters indexing the functionality of both branches of the ANS, measured at baseline, predicted cluster membership. Our results are a first step in detecting dysfunctional ANS reactivity in general population.

Go to Bed and You MIGHT Feel Better in the Morning—the Effect of Sleep on Affective Tone and Intrusiveness of Emotional Memories

Purpose of Review

It is important to examine what effect sleep has after an emotional experience. More knowledge about this topic could help inform us whether there are any potential sleep interventions that could help make sure that memories of negative emotional experiences are processed in the most adaptive manner possible.

Recent Findings

Findings on the role of sleep in altering reactivity to emotional stimuli have been highly varied, with significant findings in opposite directions. A new exciting development in the field is several studies finding that sleep seems to make memories of negative experiences less intrusive.

Summary

This review has mainly aimed to give an overview of the field, and of which issues need to be resolved. We argue for there being a strong need for standardization of how data are analyzed and presented, as well as for better methods for determining to what extent the effects of sleep are specific for a particular memory, or represent general changes in emotional reactivity.

Sleep preserves subjective and sympathetic emotional response of memories

Sleep consolidates episodic content of emotional memories. Whether it likewise preserves or, to the contrary, depotentiates the emotional response associated with memory content is unclear, as there is conflicting evidence. In the current study, we investigated the influence of an afternoon nap (2-hr nap opportunity) on emotional responses of memories using multiple simultaneous measures. Young adults viewed 45 negative and 45 neutral pictures before taking a nap (measured with polysomnography) or remaining awake. Following the nap or wake period, participants viewed the same pictures intermixed with novel ones and indicated whether they remembered each picture. Emotional response to each picture was measured at both time points both subjectively, with valence and arousal ratings, and objectively, with recordings of electrodermal activity, electrocardiography, and corrugator supercilii electromyography. Compared to waking, a nap led to preserved subjective valence for negative pictures and preserved/increased skin conductance response in general. On the other hand, heart rate deceleration response decreased over the nap compared to wake interval, and this result was not influenced by picture type. These data suggest that sleep consolidates aspects of both subjective and physiological emotional response associated with episodic memory content. While sympathetic response appears to be preserved over sleep, parasympathetic response may be diminished.

Associations of sympathetic and parasympathetic activity in job stress and burnout: A systematic review

This systematic review examines the relationship between sympathetic and parasympathetic activity on the one hand and job stress and burnout on the other, and is registered at PROSPERO under CRD42016035918. Background: Previous research has shown that prolonged job stress may lead to burnout, and that differences in heart rate variability are apparent in people who have heightened job stress. Aims: In this systematic review, the associations between job stress or burnout and heart rate (variability) or skin conductance are studied. Besides, it was investigated which–if any–guidelines are available for ambulatory assessment and reporting of the results. Methods: We extracted data from relevant databases following the PRESS checklist and contacted authors for additional resources. Participants included the employed adult population comparing validated job stress and burnout questionnaires examining heart rate and electrodermal activity. Synthesis followed the PRISMA guidelines of reporting systematic reviews. Results: The results showed a positive association between job stress and heart rate, and a negative association between job stress and heart rate variability measures. No definite conclusion could be drawn with regard to burnout and psychophysiological measures. No studies on electrodermal activity could be included based on the inclusion criteria. Conclusions: High levels of job stress are associated with an increased heart rate, and decreased heart rate variability measures. Recommendations for ambulatory assessment and reporting (STROBE) are discussed in light of the findings.

Interactions of time of day and sleep with between-session habituation and extinction memory in young adult males

Within-session habituation and extinction learning co-occur as do subsequent consolidation of habituation (i.e., between-session habituation) and extinction memory. We sought to determine whether, as we predicted: (1) between-session habituation is greater across a night of sleep versus a day awake; (2) time-of-day accounts for differences; (3) between-session habituation predicts consolidation of extinction memory; (4) sleep predicts between-session habituation and/or extinction memory. Participants (N = 28) completed 4-5 sessions alternating between mornings and evenings over 3 successive days (2 nights) with session 1 in either the morning (N = 13) or evening (N = 15). Twelve participants underwent laboratory polysomnography. During 4 sessions, participants completed a loud-tone habituation protocol, while skin conductance response (SCR), blink startle electromyography (EMG), heart-rate acceleration and heart-rate deceleration (HRD) were recorded. For sessions 1 and 2, between-session habituation of EMG, SCR and HRD was greater across sleep. SCR and HRD were generally lower in the morning. Between-session habituation of SCR for sessions 1 and 2 was positively related to intervening (first night) slow wave sleep. In the evening before night 2, participants also underwent fear conditioning and extinction learning phases of a second protocol. Extinction recall was tested the following morning. Extinction recall was predicted only by between-session habituation of SCR across the same night (second night) and by intervening REM. We conclude that: (1) sleep augments between-session habituation, as does morning testing; (2) extinction recall is predicted by concurrent between-session habituation; and (3) both phenomena may be influenced by sleep.

Extinction of conditioned fear is better learned and recalled in the morning than in the evening

Sleep helps emotional memories consolidate and may promote generalization of fear extinction memory. We examined whether extinction learning and memory might differ in the morning and evening due, potentially, to circadian and/or sleep-homeostatic factors. Healthy men (N = 109) in 6 groups completed a 2-session protocol. In Session 1, fear conditioning was followed by extinction learning. Partial reinforcement with mild electric shock produced conditioned skin conductance responses (SCRs) to 2 differently colored lamps (CS+), but not a third color (CS-), within the computer image of a room (conditioning context). One CS+ (CS + E) but not the other (CS + U) was immediately extinguished by un-reinforced presentations in a different room (extinction context). Delay durations of 3 h (within AM or PM), 12 h (morning-to-evening or evening-to-morning) or 24 h (morning-to-morning or evening-to-evening) followed. In Session 2, extinction recall and contextual fear renewal were tested. We observed no significant effects of the delay interval on extinction memory but did observe an effect of time-of-day. Fear extinction was significantly better if learned in the morning (p = .002). Collapsing across CS + type, there was smaller morning differential SCR at both extinction recall (p = .003) and fear renewal (p = .005). Morning extinction recall showed better generalization from the CS + E to CS + U with the response to the CS + U significantly larger than to the CS + E only in the evening (p = .028). Thus, extinction is learned faster and its memory is better generalized in the morning. Cortisol and testosterone showed the expected greater salivary levels in the morning when higher testosterone/cortisol ratio also predicted better extinction learning. Circadian factors may promote morning extinction. Alternatively, evening homeostatic sleep pressure may impede extinction and favor recall of conditioned fear.

Sleep promotes consolidation and generalization of extinction learning in simulated exposure therapy for spider fear

Simulated exposure therapy for spider phobia served as a clinically naturalistic model to study effects of sleep on extinction. Spider-fearing, young adult women (N = 66), instrumented for skin conductance response (SCR), heart rate acceleration (HRA) and corrugator electromyography (EMG), viewed 14 identical 1-min videos of a behaving spider before a 12-hr delay containing a normal night's Sleep (N = 20) or continuous daytime Wake (N = 23), or a 2-hr delay of continuous wake in the Morning (N = 11) or Evening (N = 12). Following the delay, all groups viewed this same video 6 times followed by six 1-min videos of a novel spider. After each video, participants rated disgust, fearfulness and unpleasantness. In all 4 groups, all measures except corrugator EMG diminished across Session 1 (extinction learning) and, excepting SCR to a sudden noise, increased from the old to novel spider in Session 2. In Wake only, summed subjective ratings and SCR to the old spider significantly increased across the delay (extinction loss) and were greater for the novel vs. the old spider when it was equally novel at the beginning of Session 1 (sensitization). In Sleep only, SCR to a sudden noise decreased across the inter-session delay (extinction augmentation) and, along with HRA, was lower to the novel spider than initially to the old spider in Session 1 (extinction generalization). None of the above differentiated Morning and Evening groups suggesting that intervening sleep, rather than time-of-testing, produced differences between Sleep and Wake. Thus, sleep following exposure therapy may promote retention and generalization of extinction learning.

The effect of methadone on emotional reactivity

AIMS

Opioids have been implicated in emotion regulation. Opioid users report decreased negative emotional response, but there has been no formal study on the effect of opioid administration on emotional reactivity. The aim of this study was to investigate the effect of methadone on emotional reactivity in methadone-maintained patients.

DESIGN

Velten's mood induction procedures were used to induce elative and depressive emotional reactions in the subjects. Each group was administered both induction procedures at 0 hour and 3 hours (corresponding with trough and peak plasma methadone concentrations in methadone subjects).

SETTING

A drug treatment clinic with an out-patient methadone maintenance treatment programme.

PARTICIPANTS

Twenty-one subjects currently on methadone maintenance treatment and 21 controls with no history of opioid dependence.

MEASUREMENTS

Emotional reactivity was measured using mood visual analogue scales.

FINDINGS

At 0 hour, methadone and control subjects showed similar elation (methadone 13.2 ± 3.1 mean ± standard error of the mean [SEM], control 14.4 ± 3.7) and depression reactivity (methadone 23.6 ± 5.0, control 25.1 ± 5.0). However, at 3 hours repeated measures showed that methadone subjects had significantly decreased depression reactivity (methadone 18.5 ± 4.6, control 36.7 ± 5.7; P = 0.021) and elation reactivity (methadone 4.4 ± 1.9, control 19.0 ± 2.4) compared to controls.

CONCLUSIONS

Opioid addicts on methadone maintenance appear to be less reactive to mood induction at times of peak plasma methadone concentration than non-addict controls; this suggests that methadone blunts both elative and depressive emotional reactivity.

[The measurement of electrodermal activity]

INTRODUCTION

Electrodermal activity (EDA) is an early physiological index and the subject of constant interest, in spite of the bad reputation attached to "lie detectors". This interest is expected to increase in the future, following the development of research related to the neurobiological aspect of emotions of which it is an index. Recent data provided by functional cerebral imaging has added to the significance of this index and should result in further interest.

AIM

The authors thus re-examined the various notions related to measuring EDA, and its practical aspect as well as its mechanisms. EDA should be useful both for authors wishing to use this variable and for readers wishing to form their own critical point of view.

LITERATURE FINDINGS

The article first defines the various terms used to qualify EDA. Then, it analyses the mechanisms occurring at the sweat glands' level, showing that a distinct innervation of the sweat glands causes sweat to be released in the excretory channels, thereby allowing the recording of a negative surface potential in parallel to the lowering of skin conductance. Arguments are then pointed out to illustrate that the potential's positive phase following this first answer occurs in the case of high intensity stimulations. The study of the central command of sudation demonstrates that, several areas are involved and that different functions such as thermal regulation and motricity may interfere with emotive reactions. Difficulties regarding the mode of measurement of these answers as to their number and amplitude are also brought to light.

DISCUSSION

A particular interest of measuring EDA is its ability to highlight individual characteristic and unconscious emotional reactivity. Subjects who constitutionally present many spontaneous and therefore habitual EDA can indeed be opposed to subjects whose EDA reflexes are very few and hardly habitual. A theory suggests that for the first category, whose subjects are named labiles, emotional control may be at the origin of EDA. This characteristic brings to mind the case of antisocial subjects whose rate of EDA is also reduced, although for the latter a primitive drop in behavioral inhibition is involved. The production of EDA in response to non-conscious emotive stimulations can be objectified in the rare cases of prosopagnosia. These subjects who are unable to recognize familiar faces can produce EDA when presented faces with an emotional load. These cases contrast with the delusional denial of the Capgras syndrome where subjects do not present EDA, suggesting that the dysfunction of visual analysis occurs at a different level. There are other rare cases represented by cortical blindness where EDA shows that an unconscious emotional analysis is preserved. These subjects are known however to be capable of unconscious visual discriminations, which are possibly accompanied by EDA. This possibility of a "blind vision" is experimentally studied via subliminal vision testing (backward masking tests). These demonstrate that a rudimentary visual analysis is carried out in the subcortical circuits while taking into account the affective aspect of stimulations.

CONCLUSION

Present or future data should allow a greater comprehension of electrodermal signals, making it possible to overcome the difficulties related to their interpretation and facilitate their applications.

Napping promotes inter-session habituation to emotional stimuli

The effects of a daytime nap on inter-session habituation to aversive visual stimuli were investigated. Healthy young adult volunteers viewed repeated presentations of highly negative and emotionally neutral (but equally arousing) International Affective Picture System (IAPS) photographs during two afternoon sessions separated by 2.5h. Half of the photographs were shown at both sessions (Repeated Sets) and half differed between sessions (Novel Sets). For each stimulus presentation, evoked skin conductance response (SCR), heart-rate deceleration (HRD) and corrugator supercilii EMG response (EMG), were computed and range corrected using respective maximum session-1 responses. Following each presentation, subjects rated each photograph on dimensions of pleasantness and arousability. During the inter-session interval, Nap subjects had a 120-min polysomnographically monitored sleep opportunity, whereas Wake subjects watched a non-stimulating video. Nap and Wake subjects did not differ in their subjective ratings of photographs. However, for Repeated-Set photographs, Nap subjects demonstrated greater inter-session habituation in SCR and EMG but a trend toward lesser inter-session habituation in HRD. These group differences were absent for Novel-Set photographs. Group differences across all measures were greater for negative stimuli. Occurrence of SWS during the nap was associated with greater inter-session habituation of EMG whereas occurrence of REM was associated with lesser inter-session habituation of SCR to negative stimuli. Sleep may therefore promote emotional adjustment at the level of somatic responses. Physiological but not subjective inter-session habituation to aversive images was enhanced by a daytime nap.

An ERP investigation of emotional processing in European and Japanese individuals

This article examined neural time course differences in the processing of emotional pictures in European and Asian individuals. Event-related potentials (ERPs) were recorded in 15 French and 15 Japanese volunteers during the presentation of neutral and emotional pictures in their own country. ERPs were analyzed by means of spatio-temporal Principal Component Analysis (PCA) and allow to evaluate cultural influences on emotional processing along three temporal windows: 105 to 140 ms, 176 to 230 ms and 255 to 455 ms. Main results highlight that (1) early ERP components coded emotional charge but were not modulated by cultural background, (2) later components showed a significant decrease of amplitudes at parieto-occipital areas for Japanese participants compared to French ones in emotional condition. These findings suggest that, in both populations, similar neurocognitive processes are involved in the early stage of the emotional stimuli processing and effects observed on later components may reflect a poorer engagement of parietal areas, known to be involved in emotional arousal dimension. Considering that cognitive judgments were similar in both populations, electrophysiological findings suggest that cultural influences on later stage of emotional processing could be related to the known lower level of emotionally expressive behavior in Japanese than in Caucasians.