Regular Article
Electrophysiological correlates of emotional meaning in
context in relation to facets of schizotypal personality traits:
A dimensional study
Sarah Terrien,
MSc,
1Pamela Gobin,
PhD,
1Galina Iakimova,
PhD,
2Alexandre Coutté,
PhD,
2Flavien Thuaire,
PhD,
3Véronique Baltazart,
PhD,
1Pascale Mazzola-Pomietto,
PhD3and
Chrystel Besche-Richard,
PhD1,4*
1Cognition, Health, Socialisation Laboratory, University of Reims Champagne-Ardenne, Reims,2Anthropology, Cognitive
and Social Psychology Laboratory, LAPCOS, University of Nice-Sophia Antipolis, Nice,3Timone Neuroscience Institute,
Marseille,4French Universitary Institute, Paris, France
Aims: The aim of this study was to investigate the neurocognitive processes mediating the processing of emotional information during the integration of contextual and social information in a schizotypal population.
Methods: One hundred and thirty-one healthy par-ticipants were evaluated using the Schizotypal Per-sonality Questionnaire and event-related potentials were recorded during a linguistic task in which par-ticipants read sentence pairs describing short social situations to themselves. The first sentence implicitly conveyed the positive or negative emotional state of a character. The second sentence was emotionally con-gruent or inconcon-gruent with the first sentence. Results: Across our overall sample, our results revealed a greater N400 effect at right sites than left sites, whereas the late positive component effect was
only observed at left sites. Concerning the correlation results, we observed a negative link between positive and global schizotypy and N400 modulation in response to congruent targets for positive context sen-tences. Results also showed a positive correlation between negative schizotypy and late positive com-ponent modulation in response to congruent targets for negative context sentences.
Conclusions: These results suggest that the different facets of the schizotypal personality traits influenced the integration of emotional context at the level of both early and later-mobilized neurocognitive processes.
Key words: emotional context, late positive
compo-nent, N400, schizotypy, vulnerability.
S
OME STUDIES HAVE suggested that schizotypal individuals might be at some level of risk for later psychosis.1–3 In line with the idea that schizotypy might be situated within the continuum of schizo-phrenia vulnerability,4 most studies support the concept of a three-factor model of schizotypy, whichcorresponds to the three-syndrome model of schizo-phrenia:5 (i) positive (quasi-psychotic symptoms, such as hallucinations and delusions); (ii) negative (alogia, apathy and amotivation); and (iii) disorga-nized (odd speech and behavior). These three trait facets or dimensions can be measured using the Schizotypy Personality Questionnaire (SPQ).3
Similar cognitive4 and social dysfunctions5 may occur in people with schizophrenia and those who present schizotypal personality traits (SZT). For example, people who exhibit SZT describe facial expressions as being more negative than they really are6 and consider that neutral expressions depict
*Correspondence: Chrystel Besche-Richard, PhD, Laboratoire Cognition, Santé, Socialisation, C2S, EA6291, Université de Reims Champagne-Ardenne, 57, Rue Pierre Taittinger, 51096 Reims, Cedex, France. Email: chrystel.besche@univ-reims.fr
Received 28 February 2015; revised 28 September 2015; accepted 15 October 2015.
anger,7thus suggesting a negative interpretative bias. In schizophrenia, an electrophysiological study has suggested a failure in the emotion evaluation process,8and especially when the emotional valence is positive. Beyond these results, the literature is undecided about whether difficulties in emotion rec-ognition are only found in certain dimensions of schizotypy. For example, one study has shown that difficulties in emotion recognition are associated with global schizotypal traits and not with any spe-cific schizotypal trait.7 Other research has suggested that people with global and positive SZT are globally impaired in emotion recognition, whereas in indi-viduals with high negative SZT scores, these difficul-ties are limited to the recognition of positive emotions. Finally, individuals with disorganized SZT have not been found to present emotion recognition difficulties.8Nevertheless, Kerns has shown that the positive dimension of schizotypy9 and disorganized dimension of schizotypy10 are associated with emo-tional confusion and increased emoemo-tionality. A more recent study found that negative SZT were linked to difficulties in emotion recognition, and in particular the recognition of negative facial expressions, and that global SZT were related to impaired emotion recognition, and in particular the recognition of posi-tive emotions.11
Beyond emotional processing, Baez et al. recently suggested that the ability to integrate contextual information may constitute a potential mechanism involved in the comprehension of emotional and social information.11In schizophrenia, the abnormal use of context during language comprehension is a well-established phenomenon reported by both behavioral12and event-related brain potential (ERP) studies.13 ERP studies dealing with context integra-tion have focused on two components: N400 and the late positive component (LPC). Initially described by Kutas and Hillyard,12N400 is a negative component whose amplitude is greatest at approximately 400 ms after the stimulus. This negativity is aroused by a target word presented in conditions in which the semantic context is manipulated. This context may consist of a prime word (word pairs), an entire sen-tence or a block of several sensen-tences (for a review, see Cermolacce et al.13). N400 amplitude is greater in response to words that are incongruous, unexpected or inappropriate in the context. As described below, this component can be observed in sentence presen-tation conditions. When two sentences differ in terms of the level of predictability of the final word, the
amplitude of the N400 component is greater for the sentence containing the less predictable final word (e.g. Kutas and Hillyard14). N400 has been reported for both auditory and visual modes of presentation (for reviews, see Kiang and Kutas15and Kutas16). LPC is a positive component that emerges between 300 and 900 ms after the stimulus. The functional inter-pretation of LPC is a matter of considerable debate in the literature.13 In effect, while most studies have found that its amplitude increases in response to vio-lations of syntax (e.g. Hagoort17), other authors suggest that this component might also be associated with the general updating of the context,18the atten-tive analysis of the global meaning of the sentence,19 or indeed with the analysis and verification mecha-nisms (e.g. Coulson and Kutas20). The mean ampli-tude of the LPC is larger when participants detect an incongruence with a preceding semantic context16–18 or with previous affective stimuli.16
According to McClure et al., the ability to take account of context may be specifically disturbed in the schizophrenia spectrum.19 Niznikiewicz et al. demonstrated that the amplitude of the N400 com-ponent in individuals with SPD is more negative during the presentation of sentences with a semanti-cally congruent ending than it is in healthy partici-pants.20,21This result was interpreted as indicating the presence of an abnormality in the mechanisms responsible for processing congruent contextual information in SPD.
The aim of the current study was to investigate, with the ERP method, the impact of the different dimensions of schizotypal personality on the neurocognitive mechanisms involved in the integra-tion of emointegra-tional and contextual informaintegra-tion. We chose to focus on the exploration of the N400 and LPC components. Given that the topographical dis-tribution of the N400 has traditionally been found at right sites16and that LPC has been described as being greater at left sites,12we expected to observe, across our overall sample, a difference in the amplitude of the N400 and the LPC effect across the scalp. Con-cerning the link between SPQ scores and the integra-tion of emointegra-tional informaintegra-tion, we hypothesized that the polarity of the context valence (i.e. positive or negative) should influence the processing of contex-tual information. Given the disparity of opinion and the absence of consensus in the current literature on ‘the precise implications of the different facets of the SPQ in the processes involved in emotional process-ing,’ we wanted to explore the link between all the
different facets of the SPQ and the modulation of N400 and LPC during emotional context integration. Finally, it has already been shown that the LPC and N400 do not reflect the same stage of cognitive pro-cessing: compared to the N400 component, LPC tends more to reflect an aspect of the cognitive or executive control of language.22 We therefore assumed that SZT modulates N400 and LPC in dif-ferent ways. We expected to observe: (i) in our overall sample, that the N400 effect would be more pro-nounced at right sites, whereas the LPC effect would be more pronounced at left sites; (ii) that the facets of SZT affect contextual integration processes differently depending on the polarity of the emotional context; and (iii) that the facets of SZT affect context integra-tion processes differently depending on the stage of emotional context integration (N400 and LPC).
METHOD
Participants
One hundred and thirty-one participants (106 women; mean age= 22.53 ± 5.53 years; mean years of education= 13.87 ± 2.60) were recruited from the University of Reims Champagne-Ardenne, the Uni-versity of Nice Sophia Antipolis and the Institut de Neuroscience de la Timone in Marseille, France. All participants were French native speakers, right-handed, had normal or corrected-to-normal vision, and had no history of reading disabilities. They also did not self-report any past or present history of neu-rological or psychiatric disorders in connection with themselves or their first-degree relatives and were not taking any psychotropic medicaments. The experi-mental design was approved by the National Ethics Committee (Comité de Protection des Personnes – Est III of the University Hospital of Nancy, permit number: 2013-A000493-42). Anonymity was
respected for all participants, who signed written informed consent prior to the study. All the partici-pants completed the SPQ.3 The SPQ is a 74-item (Yes/No) self-report measure administered to assess schizotypal traits in the general population. It pro-vides a global score and a score on three factors, namely the cognitive–perceptual, interpersonal and disorganized dimensions. Participants also com-pleted the Mill Hill Vocabulary test,23which assesses stored verbal knowledge and its retrieval.
Stimuli and design
The stimuli consisted of 66 short written prime/ context sentences (6–12 words) which implicitly con-veyed either the positive or negative emotional states of a person (e.g. negative: ‘The girl has lost her best friend’). The prime sentence was followed by a written ‘target’ sentence (3–5 words) ending in an emotional adjective. A distinction was made between two types of target sentence: (i) 22 target sentences ending with an adjective that was congruent with the character’s emotional state (e.g. ‘The girl is sad’) as implicitly described in the prime sentence; and (ii) 22 target sentences ending with an adjective that was incongruent with the character’s emotional state (e.g. ‘The girl is happy’) as implicitly described in the prime sentence (see Fig. 1). This design resulted in four experimental conditions each composed of 11 items: (i) Negative context – Emotionally Incongru-ent target sIncongru-entence; (ii) Negative context – Emotion-ally Congruent target sentence; (iii) Positive context – Emotionally Incongruent target sentence; and (iv) Positive context – Emotionally Congruent target sen-tence (Table 1). In order to verify that the final adjec-tives in the different conditions matched for length and frequency in the language, we conducted a two-way repeated-measures analysis of variance (ANOVA) with two within-subjects factors: ‘Congruency’ (2:
+ (2000 ms) Prime sentence (3500 ms) The (500 ms) student (500 ms) is (500 ms) morose (500 ms) Blank (750 ms)
congruent vs incongruent) × ‘Emotional valence’ (2: positive, negative). TheANOVArevealed no significant
effect for either length or frequency (all Ps> 0.10). The final adjectives in the different experimental con-ditions were therefore matched for length and fre-quency in the language according to the database (Lexique3.124). They were never repeated for one and the same participant. Additional filler sentences were included: 22 target sentences were ‘neutral’ with regard to the contextually implied emotional state of the character (e.g. ‘The girl is seated’) and did not share any emotional association with the priming sentence.
The inter-trial interval was 6740 ms. Sentences were presented with E-Prime software (Psychology Software Tools, Pittsburgh, PA, USA) (see Fig. 1). The only instruction given to the participants was to read the set of sentences carefully.
All the emotional adjectives used in the target sen-tences had been evaluated by 204 students (not included in the study) to ensure that they had either a positive or a negative valence (7-point Likert scale ranging from−3 for negative to 3 for positive items, respectively). Each of the selected negative and posi-tive items had a score of less than−1.5 or more than 1.6, respectively. The emotional valence of the context was evaluated by two independent experts.
Electroencephalographic recording and
data analysis
Electroencephalographic (EEG) activity was re-corded using a 32-channel Electrocap (BrainAmp, BrainProducts, Munich, Germany) arranged on the scalp according to the international 10–20 system. The reference electrode was positioned at an equal distance from Fz and Cz and the ground electrode was located between Fz and the pre-frontal sites. The electrode impedance was held below 5 kΩ. The ampli-fication gain was 1000. To record the
electro-oculogram, two electrodes derived from FP1 and FP2 were placed below the right eye and on the external canthus of the left eye and set to an amplification gain of 500. The EEG signal was digitized online at a sampling rate of 250 Hz, with bandpass half-amplitude cut-offs of 0.1–100 Hz, and was filtered using a 30-Hz low-pass filter. Before segmentation, all the electrodes were re-referenced offline to the digital average of the activity at the left and right mastoids. The EEG was segmented 200 ms before and 1500 ms after target onset. Baseline correction was performed for the 200-ms epoch before target onset. Eye blinks were checked for using the Gratton and Coles method by means of an automated analysis performed by BrainVision Analyzer (BrainProducts). Artifacts were also checked for by means of an automated analysis performed by BrainVision Analyzer. The following artifact rejection criteria were applied for the period 200 ms before to 200 ms after each segment: (i) maximum permitted voltage of 50μV/ms; (ii) maximum absolute difference of 100μV for a 200-ms interval; and (iii) minimum required activity in a 100-ms interval of 0.5μV. A visual inspection was also performed to check for blinks and other artifacts. Only participants for whom at least 50% of segments were retained were included in the analyses. Artifact-free EEG trials were averaged separately in a 1.7-s time-window for each condition, with an equivalent mean number and range of trials being used for each average: ‘emotionally incongruent word for negative sentence’ (10.05± 1.37, 5–11), ‘emotionally congru-ent word for negative scongru-entence’ (10.41± 1.34, 5–11), ‘emotionally incongruent word for positive sentence’ (10.24± 1.27, 5–11), and ‘emotionally congruent word for positive sentence’ (10.14± 1.37, 5–11).
Data analysis
ERP were analyzed at the nine electrodes placed on and around the medial line (Fz, Pz, Cz, F3, F4, C3,
Table 1. Example of experimental material
Positive context:
‘The little girl has received all the gifts she hoped for.’
Negative context:
‘The young mother has been waiting for 2 h.’
Emotionally congruent target sentence The little girl is smiling. The young mother is annoyed. Emotionally incongruent target sentence The little girl is annoyed. The young mother is smiling.
C4, P3, P4). In order to investigate the effect of emo-tional integration processes on ERP components, the mean ERP amplitudes were submitted to a two-way repeated-measures ANOVA with four within-subjects factors: ‘Congruency,’ which refers to the emotional congruency between the context and the target sen-tences (2: congruent vs incongruent) × Emotional valence of the context sentence and is referred to as ‘Emotional valence’ here (2: positive, negative) × Antero-posterior electrode factor (3: frontal, central, parietal) × ‘Laterality’ (3: left, medial, right). The Greenhouse–Geisser correction was applied to correct violations of the assumption of sphericity when appropriate.
In order to investigate the link between the level of schizotypy and ERP modulation, we performed cor-relation analyses between SPQ scores and both N400 and LPC mean amplitude for each experimental con-dition and electrode.
Based on a visual inspection and peak detection conducted by BrainVision Analyzer, we focused our analysis on two temporal windows: 380–500 ms for N400 and then 500–900 ms for the LPC.
RESULTS
Results of
ANOVAon the ERP measures
ERP are presented in Figure 2.
The ANOVA showed a significant ‘Emotional
valence’ × ‘Laterality’ interaction effect, F(2, 258) = 5.81, P= 0.004. N400 mean amplitude was larger (i.e. more negative) for negative sentences than for positive ones at the left electrodes (Negative: 0.838μV vs Positive: 1.039 μV); equivalent for nega-tive and posinega-tive sentences at the right electrodes (Negative: 1.211μV vs Positive: 1.205 μV); and greater for positive than for negative sentences at the medial electrodes (Negative: 1.372μV vs Positive: 1.228μV).
Moreover, there was a trend toward a ‘Congruency’ × ‘Laterality’ interaction effect, F(2, 258) = 3.02,
P= 0.052. N400 mean amplitude was greater (i.e.
more negative) for incongruent sentences than for congruent ones, and this difference was largest at the right electrodes (Incongruent: 1.026μV vs Congru-ent: 1.390μV), intermediate at the medial electrodes (Incongruent: 1.439μV vs Congruent: 1.161 μV) and smallest at the left electrodes (Incongruent: 0.992μV vs Congruent: 0.885μV). No other effect was signifi-cant (all Ps> 0.10).
Bar graphs are presented in Figure 3.
The LPC
TheANOVA showed a significant ‘Emotional valence’
× ‘Laterality’ interaction effect, F(2, 258) = 4.91,
P= 0.010. LPC mean amplitude was greater (i.e.
more positive) for positive sentences than for nega-tive ones, with the difference being greater at the left electrodes (Negative: 1.627μV vs Positive: 1.830 μV) than at the right electrodes (Negative: 1.648μV vs Positive: 1.802μV), whereas LPC mean amplitude was more positive for negative than for positive sen-tences at the medial electrodes (Negative: 2.934μV vs Positive: 2.847μV).
Moreover, there was a significant ‘Congruency’ × ‘Laterality’ interaction effect, F(2, 258) = 3.48,
P= 0.033. LPC mean amplitude was larger (i.e. more
positive) for congruent sentences than for incongru-ent ones, with the difference being greater at the right electrodes (Incongruent: 1.602μV vs Congru-ent: 1.848μV) than at the medial electrodes (Incon-gruent: 2.816μV vs Congruent: 2.966 μV), and the reverse was observed at the left electrodes (Incongru-ent: 1.758μV vs Congruent: 1.698 μV). No other effect was significant.
Results of correlation analyses for the
ERP measures
The N400 component
Bravais–Pearson correlations calculated between the mean amplitude of the N400 at the Fz, Pz, Cz, F3, F4, C3, C4, P3, P4 sites and the SPQ scores revealed that: (i) the total SPQ score was negatively correlated with N400 amplitude in the Positive Congruent condition at Fz, r= −0.169; P = 0.055, F4, r = −0.188; P = 0.031, and Cz, r= −0.189; P = 0.043; and (ii) the Positive SPQ subscale score was negatively correlated with N400 amplitude in the Positive Congruent condition at F4, r= −0.168; P = 0.055 and Cz, r = −0.178;
P= 0.030. These results indicated that: (i) higher
global SPQ scores were associated with more negative N400 amplitude in the Positive Congruent condition at the Fz, F4 and Cz electrodes; and (ii) higher Posi-tive SPQ scores were associated with more negaPosi-tive N400 amplitude in the Positive Congruent condition at the F4 and Cz electrodes.
The LPC
Bravais–Pearson correlations calculated between the mean amplitude of the LPC at the Fz, Pz, Cz, F3, F4,
Figure 2. Event-related potentials for the nine electrodes and topographical representations as a function of type of Emotional valence (negative above and positive below) and Congruency (congruent vs incongruent). ( ) Congruent. ( ) Incongruent.
C3, C4, P3, P4 sites and the SPQ scores revealed that the Negative SPQ subscale score was positively corre-lated with LPC amplitude in the Negative Congruent condition at Cz, r= −0.186; P = 0.033. These results indicated that higher negative SPQ scores were asso-ciated with more positive LPC amplitude in the Nega-tive Congruent condition at the Cz electrode.
DISCUSSION
The current study investigated whether the integra-tion of emointegra-tional context informaintegra-tion is influenced by the level of the different facets of SZT and by context valence in a general population.
N400
For our overall sample, the N400 effect was observed with the effect being more pronounced at the right sites. This finding is consistent with the classical centro-parietal right distribution of the N400 effect.16,25–27 Furthermore, the fact that the N400 effect was greater at right sites is consistent with the right hemisphere hypothesis (i.e. the hypothesis that the right hemisphere seems to be predominant in emotional processing)28(for a review, see Borod23).
Our findings showed that the higher the global SPQ score was, the more negative the N400 ampli-tude was in the Positive context – Emotionally Con-gruent target sentence condition at the Fz, F4 and Cz electrodes. This result seems to indicate that the global SPQ score is positively linked to the difficulty of integrating a positive emotional context. Indeed,
the congruent final sentence was perceived as being less congruent (reflected by a more negative N400) when the global SPQ score was higher. This result is consistent with the N400 effect, associated with the reduction of N400 amplitude in response to seman-tically congruent words or sentences, which has been found in healthy people with high schizotypal scores29 or in clinical schizotypal populations.30,31 The limitations affecting positive context integration seem to be consistent with studies that have demon-strated an association between SPD or SZT and an impaired ability to identify positive emotions.11,32We obtained a similar result in connection with positive SZT: the higher the positive SPQ score, the greater the N400 amplitude in the Positive context – Emotion-ally Congruent target sentence condition at the F4 and Cz electrodes. This result seems to illustrate a deficit in the integration of positive emotional con-textual information in individuals with a high posi-tive schizotypy score. The limitation associated with positive emotional contexts could be explained by the fact that people with positive schizotypy seem to be better able to remember negatively valenced items.9
LPC
LPC amplitude in our overall sample was larger for the incongruent emotional stimuli than for the con-gruent stimuli only at the left sites. This result is consistent with the classically observed LPC modula-tion, in which there is a larger LPC amplitude.33,34 Thus, our results seem to indicate that the
modula-(a) (b) 0 0.5 1 1.5 2 2.5 3 3.5 LPC mean amplitude LPC 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.8 2 1.6 Positive Negative Left sites Medial sites Right sites
N400 mean amplitude
N400
Positive Negative Negative Positive Positive Negative
Left sites Medial sites Right sites Positive Negative Negative Positive
Figure 3. (a) N400 mean amplitude and (b) late positive component (LPC) mean amplitude at left, medial and right sites as a function of type of Emotional valence (positive or negative sentences) and Congruency (congruent or incongruent). Error bars indicate standard deviation. ( ) Congruent. ( ) Incongruent.
tion of the LPC is also sensitive to the integration of emotional context at the left sites, with a larger ampli-tude being observed for emotionally incongruent stimuli than for emotionally congruent stimuli. If, like Werheid et al.,33 we consider that LPC modula-tion reflects the priming of emomodula-tional expressions, we could interpret the result observed at the right sites as an emotional priming effect affecting our whole sample.
On the other hand, at the right and medial sites, the LPC amplitude was larger for congruent than for incongruent emotional targets. These results suggest that the topological LPC effect was restricted to left sites, unlike in the case of the N400 effect. This result is consistent with a study that has shown that late positivity (300–900 ms) leads to increased and sig-nificant left asymmetry across temporo-parietal regions.12
Concerning the link between SPQ and LPC modu-lation, our results showed that the higher the negative SPQ score is, the more positive the LPC amplitude is in the Negative context – Emotionally Congruent target sentence condition, but only at the Cz elec-trode. This result seems to indicate that the negative SPQ score is positively linked to the difficulty in inte-grating a negative emotional context. Indeed, the congruent final sentence was perceived as being less congruent (reflected by a more positive LPC) when the negative SPQ score increased. Studies have shown that people with high negative schizotypal trait scores present difficulties in emotion recognition that are restricted to positive emotions8 or negative emo-tions11only. Despite this, the two studies in question did not use the same methodology as our own. In effect, the study by Williams et al.11 used an emo-tional facial expression recognition paradigm, whereas the study by Abbott et al.8used short videos. The participant’s task was to identify the emotion displayed by the target actor in the scene. Thus, the Abbott et al. study required the integration of dynamic, varied information relating, for example, to posture, intonation, facial expressions, etc.; that is, information that was not provided in our paradigm or that used by Williams et al. Thus, in terms of the integration of static compared to dynamic informa-tion, the design of our study seems to be closer to that used by Williams et al.11 Our results, like those reported by Williams, therefore suggest that individu-als with a high negative schizotypy score might find it difficult to integrate negative emotional information, whereas, according to Abbott et al.,8they do not seem
to exhibit any difficulty in the integration of negative multi-modal information.
The differences observed between the N400 and LPC results could be due to the fact that different mechanisms underpin these components. Given that the N400 component reflects the detection of incon-gruity (semantic, as seen in previous studies,12 or emotional, as in our study) and LPC reflects a syntac-tic process that is sensitive to contextual influences and involves an extensive integrative semantic reanalysis,35 the absence of a link between SPQ-global/SPQ-positive scores and LPC amplitudes could be explained by ‘the deployment of a late-occurring compensation mechanism,’ which is involved in positive emotional integration (LPC) in participants with high global and positive schizotypal traits. The reanalysis of the positive emotional context in individuals with high positive and global schizotypal traits seems to be beneficial. In contrast, the fact that the negative schizotypy score was linked to abnormalities in LPC amplitude but not N400 amplitude is surprising. This result needs to be con-sidered with caution because statistical analysis of our overall sample does not suggest that our experi-mental material was sensitive to the classical LPC effect, especially at the medial sites. However, it is possible that these results indicate that people with high negative schizotypy traits make mistakes in the reanalysis of the emotional context.
Overall, as expected, our pattern of results seems to indicate that: (i) across our overall sample, the N400 effect was more pronounced at right sites, whereas the LPC effect was exclusively limited to right sites; (ii) schizotypal personality traits affect contextual integration processes differently depending on the polarity of the emotional context; and (iii) schizotypal personality traits affect contextual inte-gration processes differently depending on the stage of emotional context integration.
In conclusion, we can summarize that global and positive SPQ scores are linked to modifications in cognitive processes involving the integration of posi-tive emotional contexts as reflected by the N400 com-ponent. This possibly suggests that individuals with a high global and positive SPQ score have difficulties in understanding and integrating indices quickly in response only to the positive context sentences. However, global and positive SPQ scores were not found to be correlated with the late-occurring inte-gration processes (LPC). This could point to the deployment of a compensatory mechanism for the
contextual integration of emotionally positive infor-mation that functions efficiently in people with high levels of positive and global SZT. On the other hand, negative SPQ score was linked to an impairment of the cognitive processes involved in negative emo-tional context integration, as reflected by the LPC but not by the N400 component. This could indicate that individuals who have a high negative SPQ score expe-rience difficulties during the reanalysis of negative emotional contexts.
ACKNOWLEDGMENTS
This work was supported by the French Agence Nationale de la Recherche (ANR) (ANR- 11-EMCO-001 01) and the Conseil Régional Champagne-Ardenne. We thank Solange Mardaga for her help with the ERP method. We are grateful to Tim Pownall for reviewing the English language.
DISCLOSURE STATEMENT
The authors have no conflicts of interest to declare.
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