Fabien D'Hondt

Early brain-body impact of emotional arousal

Current research in affective neuroscience suggests that the emotional content of visual stimuli activates brain–body responses that could be critical to general health and physical disease. The aim of this study was to develop an integrated neurophysiological approach linking central and peripheral markers of nervous activity during the presentation of natural scenes in order to determine the temporal stages of brain processing related to the bodily impact of emotions. More specifically, whole head magnetoencephalogram (MEG) data and skin conductance response (SCR), a reliable autonomic marker of central activation, were recorded in healthy volunteers during the presentation of emotional (unpleasant and pleasant) and neutral pictures selected from the International Affective Picture System (IAPS). Analyses of event-related magnetic fields (ERFs) revealed greater activity at 180 ms in an occipitotemporal component for emotional pictures than for neutral counterparts. More importantly, these early effects of emotional arousal on cerebral activity were significantly correlated with later increases in SCR magnitude. For the first time, a neuromagnetic cortical component linked to a well-documented marker of bodily arousal expression of emotion, namely, the SCR, was identified and located. This finding sheds light on the time course of the brain–body interaction with emotional arousal and provides new insights into the neural bases of complex and reciprocal mind–body links.

Implicit emotional processing in peripheral vision: Behavioral and neural evidence

Emotional facial expressions (EFE) are efficiently processed when both attention and gaze are focused on them. However, what kind of processing persists when EFE are neither the target of attention nor of gaze remains largely unknown. Consequently, in this experiment we investigated whether the implicit processing of faces displayed in far periphery could still be modulated by their emotional expression. Happy, fearful and neutral faces appeared randomly for 300 ms at four peripheral locations of a panoramic screen (15 and 30° in the right and left visual fields). Reaction times and electrophysiological responses were recorded from 32 participants who had to categorize these faces according to their gender. A decrease of behavioral performance was specifically found for happy and fearful faces, probably because emotional content was automatically processed and interfered with information necessary to the task. A spatio-temporal principal component analysis of electrophysiological data confirmed an enhancement of early activity in occipito-temporal areas for emotional faces in comparison with neutral ones. Overall, these data show an implicit processing of EFE despite the strong decrease of visual performance with eccentricity. Therefore, the present research suggests that EFE could be automatically detected in peripheral vision, confirming the abilities of humans to process emotional saliency in very impoverished conditions of vision.

Below and beyond the recognition of emotional facial expressions in alcohol dependence: from basic perception to social cognition

Studies that have carried out experimental evaluation of emotional skills in alcohol-dependence have, up to now, been mainly focused on the exploration of emotional facial expressions (EFE) decoding. In the present paper, we provide some complements to the recent systematic literature review published by Donadon and de Lima Osório on this crucial topic. We also suggest research avenues that must be, in our opinion, considered in the coming years. More precisely, we propose, first, that a battery integrating a set of emotional tasks relating to different processes should be developed to better systemize EFE decoding measures in alcohol-dependence. Second, we propose to go below EFE recognition deficits and to seek for the roots of those alterations, particularly by investigating the putative role played by early visual processing and vision–emotion interactions in the emotional impairment observed in alcohol-dependence. Third, we insist on the need to go beyond EFE recognition deficits by suggesting that they only constitute a part of wider emotional deficits in alcohol-dependence. Importantly, since the efficient decoding of emotions is a crucial ability for the development and maintenance of satisfactory interpersonal relationships, we suggest that disruption of this ability in alcohol-dependent individuals may have adverse consequences for their social integration. One way to achieve this research agenda would be to develop the field of affective and social neuroscience of alcohol-dependence, which could ultimately lead to major advances at both theoretical and therapeutic levels.

Fearful faces impact in peripheral vision: Behavioral and neural evidence

Many studies provided evidence that the emotional content of visual stimulations modulates behavioral performance and neuronal activity. Surprisingly, these studies were carried out using stimulations presented in the center of the visual field while the majority of visual events firstly appear in the peripheral visual field. In this study, we assessed the impact of the emotional facial expression of fear when projected in near and far periphery. Sixteen participants were asked to categorize fearful and neutral faces projected at four peripheral visual locations (15° and 30° of eccentricity in right and left sides of the visual field) while reaction times and event-related potentials (ERPs) were recorded. ERPs were analyzed by means of spatio-temporal principal component and baseline-to-peak methods. Behavioral data confirmed the decrease of performance with eccentricity and showed that fearful faces induced shorter reaction times than neutral ones. Electrophysiological data revealed that the spatial position and the emotional content of faces modulated ERPs components. In particular, the amplitude of N170 was enhanced by fearful facial expression. These findings shed light on how visual eccentricity modulates the processing of emotional faces and suggest that, despite impoverished visual conditions, the preferential neural coding of fearful expression of faces still persists in far peripheral vision. The emotional content of faces could therefore contribute to their foveal or attentional capture, like in social interactions.

Are visual impairments responsible for emotion decoding deficits in alcohol-dependence?

Emotional visual perception deficits constitute a major problem in alcohol-dependence. Indeed, the ability to assess the affective content of external cues is a key adaptive function, as it allows on the one hand the processing of potentially threatening or advantageous stimuli, and on the other hand the establishment of appropriate social interactions (by enabling rapid decoding of the affective state of others from their facial expressions). While such deficits have been classically considered as reflecting a genuine emotion decoding impairment in alcohol-dependence, converging evidence suggests that underlying visual deficits might play a role in emotional alterations. This hypothesis appears to be relevant especially as data from healthy populations indicate that a coarse but fast analysis of visual inputs would allow emotional processing to arise from early stages of perception. After reviewing those findings and the associated models, the present paper underlines data showing that rapid interactions between emotion and vision could be impaired in alcohol-dependence and provides new research avenues that may ultimately offer a better understanding of the roots of emotional deficits in this pathological state.

Electrophysiological correlates of problematic Internet use: Critical review and perspectives for future research

Problematic behaviors have emerged with the exponential development of the Internet access, with some individuals failing to constrain their Internet use despite its negative impact on their daily lives. Recent neuropsychological and neuroscience studies have suggested that problematic Internet use is notably associated with increased cue-reactivity and reduced inhibitory control. This review of the electroencephalography (EEG) literature shows that most studies have found that impaired self-control abilities (i.e., inhibition and error monitoring) are associated with underactivated frontal regions in problematic Internet users (PIUs). However, some EEG studies in the domain have also demonstrated alterations in the processing of Internet-related cues and emotional stimuli. As a whole, these data therefore suggest that both reflective (top-down) and automatic/affective (bottom-up) systems, postulated by dual-process models as being determinants in decision making, are impaired among PIUs. On this basis, new research avenues are proposed to better understand the development and maintenance of problematic Internet use, according to six main directions respectively related to (1) the identification of vulnerability biomarkers, (2) the investigation of possible lower level cognitive impairments, (3) the exploration of core reflective and automatic/affective symptoms, (4) the evaluation of Internet use heterogeneity and comorbidities, (5) the development of new neuroscience strategies and (6) the elaboration of behavioral and cognitive interventions.

Electrophysiological studies in Internet addiction: A review within the dual-process framework

Abstract The increase of pathological Internet use recently led to the identification of an “Internet addiction” disorder. While its diagnosis criteria remain unclear, the behavioral consequences of Internet addiction have been widely explored. Its cerebral correlates have also been investigated using electroencephalography, but obtained results have not yet been integrated in a sound theoretical framework. This paper aims at reviewing these studies and at analyzing their results through a dual-process perspective. A systematic literature search was conducted using Pubmed to identify studies in English exploring neural oscillations and/or event-related potentials in individuals displaying problematic Internet use. The 14 articles finally selected show that Internet addiction shares essential features with other addictive states, mainly a joint hypo-activation of the reflective system (decreased executive control abilities) and hyper-activation of the automatic-affective one (excessive affective processing of addiction-related cues). Despite the currently limited data, dual-process models thus appear useful to conceptualize the imbalance between cerebral systems in Internet addiction. We finally propose that future electrophysiological studies should better characterize this disequilibrium between controlled-deliberate and automatic-affective networks, notably by using event-related potentials paradigms focusing on each system separately and on their interactions, but also by better specifying the potential differences between sub-categories of Internet addiction.

Electrophysiological correlates of performance monitoring in binge drinking: Impaired error-related but preserved feedback processing

OBJECTIVE Performance monitoring, which allows efficient behavioral regulation using either internal (error processing) or external (feedback processing) cues, has not yet been explored in binge drinking despite its adaptive importance in everyday life, particularly in the regulation of alcohol consumption. Capitalizing on a theoretical model of risky behaviors, the present study aimed at determining the behavioral and electrophysiological correlates of the cognitive (inhibition) and motivational (reward sensitivity) systems during performance monitoring. METHODS Event-related potentials were recorded from 20 binge drinkers and 20 non-binge drinkers during two experimental tasks, a speeded Go/No-Go Task [investigating internal error processing by Error-Related Negativity (ERN) and error positivity (Pe)] and a Balloon Analogue Risk Task [investigating external feedback processing by Feedback-Related Negativity (FRN) and P3]. RESULTS While no group differences were observed at the behavioral level, electrophysiological results showed that binge drinkers, despite having intact feedback-related components, presented modified error-monitoring components (i.e. larger ERN amplitude, delayed Pe latency). CONCLUSIONS Internal performance monitoring is impaired in binge drinkers, showing an abnormal automatic processing of response errors (ERN) and a decreased processing of their motivational significance (Pe). SIGNIFICANCE These results suggest that the electrophysiological correlates of inhibitory control allow identifying the specific binge drinking consumption pattern.

Spatiotemporal dynamics of affective picture processing revealed by intracranial high-gamma modulations

Our comprehension of the neural mechanisms underlying emotional information processing has largely benefited from noninvasive electrophysiological and functional neuroimaging techniques in recent years. However, the spatiotemporal dynamics of the neural events occurring during emotional processing remain imprecise due to the limited combination of spatial and temporal resolution provided by these techniques. This study examines the modulations of high‐frequency activity of intracranial electroencephalography recordings associated with affective picture valence, in epileptic patients awaiting neurosurgery. Recordings were obtained from subdural grids and depth electrodes in eight patients while they viewed a series of unpleasant, pleasant and neutral pictures from the International Affective Picture System. Broadband high‐gamma (70–150 Hz) power was computed for separate 100‐ms time windows and compared according to ratings of emotional valence. Compared to emotionally neutral or pleasant pictures, unpleasant stimuli were associated with an early and long‐lasting (≈200–1,000 ms) bilateral increase in high‐gamma activity in visual areas of the occipital and temporal lobes, together with a late and transient (≈500–800 ms) decrease found bilaterally in the lateral prefrontal cortex (PFC). Pleasant pictures were associated with increased gamma activity in the occipital cortex, compared to the emotionally neutral stimuli. Consistent with previous studies, our results provide direct evidence of emotion‐related modulations in the visual ventral pathway during picture processing. Results in the lateral PFC also shed light on the neural mechanisms underlying its role in negative emotions processing. This study demonstrates the utility of intracranial high‐gamma modulations to study emotional process with a high spatiotemporal precision. Hum Brain Mapp, 36:16–28, 2015..

Heterogeneity of emotional and interpersonal difficulties in alcohol-dependence: A cluster analytic approach

BACKGROUND Emotional and interpersonal impairments have been largely reported in alcohol-dependence, and their role in its development and maintenance is widely established. However, earlier studies have exclusively focused on group comparisons between healthy controls and alcohol-dependent individuals, considering them as a homogeneous population. The variability of socio-emotional profiles in this disorder thus remains totally unexplored. The present study used a cluster analytic approach to explore the heterogeneity of affective and social disorders in alcohol-dependent individuals. METHODS 296 recently-detoxified alcohol-dependent patients were first compared with 246 matched healthy controls regarding self-reported emotional (i.e. alexithymia) and social (i.e. interpersonal problems) difficulties. Then, a cluster analysis was performed, focusing on the alcohol-dependent sample, to explore the presence of differential patterns of socio-emotional deficits and their links with demographic, psychopathological and alcohol-related variables. RESULTS The group comparison between alcohol-dependent individuals and controls clearly confirmed that emotional and interpersonal difficulties constitute a key factor in alcohol-dependence. However, the cluster analysis identified five subgroups of alcohol-dependent individuals, presenting distinct combinations of alexithymia and interpersonal problems ranging from a total absence of reported impairment to generalized socio-emotional difficulties. CONCLUSIONS Alcohol-dependent individuals should no more be considered as constituting a unitary group regarding their affective and interpersonal difficulties, but rather as a population encompassing a wide variety of socio-emotional profiles. Future experimental studies on emotional and social variables should thus go beyond mere group comparisons to explore this heterogeneity, and prevention programs proposing an individualized evaluation and rehabilitation of these deficits should be promoted.