N450 and LPC Event-Related Potential Correlates of an Emotional Stroop Task with Words Differing in Valence and Emotional Origin

Affective meaning of verbal stimuli was found to influence cognitive control as expressed in the Emotional Stroop Task (EST). Behavioral studies have shown that factors such as valence, arousal, and emotional origin of reaction to stimuli associated with words can lead to lengthening of reaction latencies in EST. Moreover, electrophysiological studies have revealed that affective meaning altered amplitude of some components of evoked potentials recorded during EST, and that this alteration correlated with the performance in EST. The emotional origin was defined as processing based on automatic vs. reflective mechanisms, that underlines formation of emotional reactions to words. The aim of the current study was to investigate, within the framework of EST, correlates of processing of words differing in valence and origin levels, but matched in arousal, concreteness, frequency of appearance and length. We found no behavioral differences in response latencies. When controlling for origin, we found no effects of valence. We found the effect of origin on ERP in two time windows: 290–570 and 570–800 ms. The earlier effect can be attributed to cognitive control while the latter is rather the manifestation of explicit processing of words. In each case, reflective originated stimuli evoked more positive amplitudes compared to automatic originated words.

The role of emotionality in the acquisition of new concrete and abstract words

A processing advantage for emotional words relative to neutral words has been widely demonstrated in the monolingual domain (e.g., Kuperman et al., 2014). It is also well-known that, in bilingual speakers who have a certain degree of proficiency in their second language, the effects of the affective content of words on cognition are not restricted to the native language (e.g., Ferré et al., 2010). The aim of the present study was to test whether this facilitatory effect can also be obtained during the very early stages of word acquisition. In the context of a novel word learning paradigm, participants were trained on a set of Basque words by associating them to their Spanish translations. Words' concreteness and affective valence were orthogonally manipulated. Immediately after the learning phase and 1 week later, participants were tested in a Basque go-no go lexical decision task as well as in a translation task in which they had to provide the Spanish translation of the Basque words. A similar pattern of results was found across tasks and sessions, revealing main effects of concreteness and emotional content as well as an interaction between both factors. Thus, the emotional content facilitated the acquisition of abstract, but not concrete words, in the new language, with a more reliable effect for negative words than for positive ones. The results are discussed in light of the embodied theoretical view of semantic representation proposed by Kousta et al. (2011).

Emotional words can be embodied or disembodied: the role of superficial vs. deep types of processing

Emotional words are processed rapidly and automatically in the left hemisphere (LH) and slowly, with the involvement of attention, in the right hemisphere (RH). This review aims to find the reason for this difference and suggests that emotional words can be processed superficially or deeply due to the involvement of the linguistic and imagery systems, respectively. During superficial processing, emotional words likely make connections only with semantically associated words in the LH. This part of the process is automatic and may be sufficient for the purpose of language processing. Deep processing, in contrast, seems to involve conceptual information and imagery of a word’s perceptual and emotional properties using autobiographical memory contents. Imagery and the involvement of autobiographical memory likely differentiate between emotional and neutral word processing and explain the salient role of the RH in emotional word processing. It is concluded that the level of emotional word processing in the RH should be deeper than in the LH and, thus, it is conceivable that the slow mode of processing adds certain qualities to the output.

Attention to affect 2.0: Multiple effects of emotion and attention on event-related potentials of visual word processing in a valence-detection task

Here we continue recent work on the specific mental processes engaged in a valence-detection task. Fifty-seven participants responded to one predefined target level of valence (negative, neutral, or positive), and ignored the remaining two levels. This enables more precise fine-tuning of neuronal pathways, compared to valence categorization where attention is divided between different levels of valence. Our group recently used valence detection with emotional words. Posterior P1 and N170 effects in the event-related potential (ERP) supported the idea of valent word forms that can be tuned by selective attention to valence. Here we report findings on three distinct posterior N2 components, P300, N400, and the late positive potential (LPP). Target but not nontarget words showed an arousal effect (emotional > neutral) on left-side early posterior negativity (180-280 ms). In contrast, an arousal effect on a sharp N2 deflection in left-minus-right difference ERPs (230-270 ms), suggesting facilitation of lexical access for emotional words, was independent of target status. This also applied to increased medial parieto-occipital N2 (260-300 ms) specific to negative words, indicating attentional capture. Medial-central N400 was specifically enhanced for negative nontarget words, further supporting attentional capture. The typical LPP arousal effect was observed, being stronger and more left-lateralized in target words. An exploratory finding concerned a broad component-overarching ERP valence effect (250-650 ms). Independent of target status, ERPs were more positive for positive than negative words. Combined with our previous results, data suggest multiple loci of emotion-attention interactions in valence detection.

Sexual Abuse Exposure Alters Early Processing of Emotional Words: Evidence from Event-Related Potentials

This study aimed to compare the time course of emotional information processing between trauma-exposed and control participants, using electrophysiological measures. We conceived an emotional Stroop task with two types of words: trauma-related emotional words and neutral words. We assessed the evoked cerebral responses of sexual abuse victims without post-traumatic stress disorder (PTSD) and no abuse participants. We focused particularly on an early wave (C1/P1), the N2pc, and the P3b. Our main result indicated an early effect (55–165 ms) of emotionality, which varied between non-exposed participants and sexual abuse victims. This suggests that potentially traumatic experiences modulate early processing of emotional information. Our findings showing neurobiological alterations in sexual abuse victims (without PTSD) suggest that exposure to highly emotional events has an important impact on neurocognitive function even in the absence of psychopathology.

Emotional Content and Source Memory for Language: Impairment in an Incidental Encoding Task

Research into the effects of emotion on source memory (i.e., memory for certain contextual details of a stimulus, such as its location, color, or temporal context) has yielded inconsistent findings. Mather and her co-workers tried to account for such inconsistencies by pointing out the relevance of the characteristics of the feature examined. Specifically, they distinguished between intrinsic and extrinsic features (Mather, 2007) and between goal-relevant and goal-irrelevant information (Mather and Sutherland, 2011). In the current study, we investigated source memory for language, which is an intrinsic feature or words. Catalan-Spanish bilinguals were tested in three experiments involving a recognition task in which they were asked about the language of presentation (Catalan or Spanish) of emotional and neutral words. In Experiments 1 and 2, source memory for negative and neutral words was assessed. In Experiment 1 participants performed an intentional encoding task in which language was a goal-relevant feature. In Experiment 2, they did an incidental encoding task in which language was also goal-relevant. Experiment 3 replicated Experiment 2 but negative words were replaced by positive words. The results showed an impairment in source memory for the language of presentation of emotional words when the encoding task was incidental, but not when it was intentional. Such impairment was observed with both negative words and positive words. The results are discussed in relation to the proposals of Mather and co-workers and point to the relevance of modulating factors, such as the intentional/incidental nature of encoding.

Robots with language

Trying to understand human language by constructing robots that have language necessarily implies an embodied view of language, where the meaning of linguistic expressions is derived from the physical interactions of the organism with the environment. The paper describes a neural model of language according to which the robot's behaviour is controlled by a neural network composed of two sub-networks, one dedicated to the non-linguistic interactions of the robot with the environment and the other one to processing linguistic input and producing linguistic output. We present the results of a number of simulations using the model and we suggest how the model can be used to account for various language-related phenomena such as disambiguation, the metaphorical use of words, the pervasive idiomaticity of multi-word expressions, and mental life as talking to oneself. The model implies a view of the meaning of words and multi-word expressions as a temporal process that takes place in the entire brain and has no clearly defined boundaries. The model can also be extended to emotional words if we assume that an embodied view of language includes not only the interactions of the robot's brain with the external environment but also the interactions of the brain with what is inside the body.

The effect of positive and negative memory bias on anxiety and depression symptoms among adolescents

OBJECTIVE

To examine the interaction effect of anxiety and depression on the intentional forgetting of positive and negative valence words.

METHODS

One hundred fifty-five grade 7 to grade 10 students participated in the study. The item-method directed forgetting paradigm was used to examine the intentional forgetting of positive-valence, negative-valence, and neutral-valence words.

RESULTS

Negative-valence words were recognized better than either positive-valence or neutral-valence words. The results revealed an anxiety main effect (p = .01, LLCI = -.09, and ULCI = -.01) and a depression main effect (p = .04, LLCI = .00, and ULCI = .24). The anxiety score was negative, whereas the depression score was positively related to the directed forgetting of negative-valence words. Regression-based moderation analysis revealed a significant anxiety × depression interaction effect on the directed forgetting of positive-valence words (p = .02, LLCI = .00, and ULCI = .01). Greater anxiety was associated with more directed forgetting of positive-valance words only among participants with high depression scores. With negative-valence words, the anxiety × depression interaction effect was not significant (p = .15, LLCI = - .00, and ULCI = .01).

CONCLUSION

Therapeutic strategies to increase positive memory bias may reduce anxiety symptoms only among those with high depression scores. Interventions to reduce negative memory bias may reduce anxiety symptoms irrespective of levels of depression.

The effect of contextual arousal on the integration of emotional words during discourse comprehension

This event-related potential (ERP) study examined the effect of contextual arousal on emotional word integration during discourse comprehension. We used two-sentence discourses as experimental materials. The first sentence served as an emotional context and described a high-arousal positive event, a low-arousal positive event, a high-arousal negative event, or a low-arousal negative event. The second sentence contained one negative word as the critical word, which was identical among different conditions. Thus, four conditions were included in the present study: high-arousal inconsistent, low-arousal inconsistent, high-arousal consistent, and low-arousal consistent. The ERP results showed that inconsistent emotional words elicited larger P200 and LPC than consistent words in the high-arousal context. However, only a P200 effect was observed for inconsistent emotional words in the low-arousal context. Our results indicate that a high-arousal context could lead to more elaborated emotional evaluation in the later stage of emotional word integration and suggest an important role of contextual arousal on the processing of emotional words during discourse processing.

Could L2 Lexical Attrition Be Predicted in the Dimension of Valence, Arousal, and Dominance?

The current study attended to predict L2 lexical attrition by means of a Decision Tree model (DT model) in three emotional dimensions, that is, the valence dimension, the arousal dimension, and the dominance dimension. A sample of 188 participants whose L1 was Chinese and L2 was English performed a recognition test of 500 words for measuring the L2 lexical attrition. The findings explored by the Decision Tree model indicated that L2 lexical attrition could be predicted in all the three emotional dimensions in two aspects: (1) among the three emotional dimensions, the valence dimension was the most powerful in predicting L2 lexical attrition, followed successively by the dominance dimension and the arousal dimension; (2) most of the neutral words in the three emotional dimensions were predicted to be inferior to emotional words in L2 attrition. In addition, the modified Revised Hierarchical Model for emotion could be adopted to justify the modulation of the emotion–memory effects upon L2 lexical attrition.

Processing emotions from faces and words measured by event-related brain potentials

Affective aspects of a stimulus can be processed rapidly and before cognitive attribution, acting much earlier for verbal stimuli than previously considered. Aimed for specific mechanisms, event-related brain potentials (ERPs), expressed in facial expressions or word meaning and evoked by six basic emotions - anger, disgust, fear, happy, sad, and surprise - relative to emotionally neutral stimuli were analysed in a sample of 116 participants. Brain responses in the occipital and left temporal regions elicited by the sadness in facial expressions or words were indistinguishable from responses evoked by neutral faces or words. Confirming previous findings, facial fear elicited an early and strong posterior negativity. Instead of expected parietal positivity, both the happy faces and words produced significantly more negative responses compared to neutral. Surprise in facial expressions and words elicited a strong early response in the left temporal cortex, which could be a signature of appraisal. The results of this study are consistent with the view that both types of affective stimuli, facial emotions and word meaning, set off rapid processing and responses occur very early in the processing stage.

Emotional processing of math-related words in people with math anxiety

BACKGROUND

Research exploring emotional responses to math-related words in individuals with math anxiety (MA) is scarce. Here, we examined MA participants' subjective emotional processing of math-related cues within Lang's bioinformational model of emotion to further understand the role of those cues in MA.

METHODS

In total, 41 high-MA and 32 low-MA undergraduates rated math-related words, along with neutral, pleasant, and unpleasant words, from the Affective Norms for English Words. The Self-Assessment Manikin was used to calculate valence, arousal, and dominance scores for each word.

RESULTS

The low-MA group rated math-related words as neutral on the three emotional scales, however, the high-MA group rated them lower and higher for valence and dominance than neutral and unpleasant words, respectively. Moreover, math-related words were rated as more and less activating than neutral and unpleasant words, respectively. The two groups significantly differed in scores on the three scales only for the math-related words.

CONCLUSIONS

These results provide evidence that individuals with high MA show altered emotional processing of math-related words, experiencing them as moderately aversive and moderately activating. The findings emphasize that the altered emotional processing of words associated with math should be considered a symptom of MA.

Inhibition in the emotional Hayling task: can hypnotic suggestion enhance cognitive control on a prepotent negative word?

Recent studies suggest that instrumental hypnosis is a useful experimental tool to investigate emotional and language processing effects. However, the capacity of hypnotic suggestions to intervene during the response inhibition of emotional words remains elusive. This study investigated whether hypnotic suggestion can improve the inhibition of prepotent negative word responses in an emotional Hayling sentence completion task. High-suggestible participants performed a computerised emotional Hayling task. They were first asked to select the appropriate words ending highly predictable sentences among two propositions (initiation part), and then to select the filler words that did not end the sentences correctly (inhibition part). Half of the expected final words had a negative emotional valence, while the other half was neutral. The task was performed in a control condition (without suggestion) and with a hypnotic suggestion to decrease emotional reactivity. The results revealed that hypnotic suggestion (compared to the control condition) hastened response times on negative final words in the inhibition part, showing that hypnotic suggestion can enhance cognitive control over prepotent negative word responses in a sentence completion task. We suggest that this modulation stems from a reduction in the emotional relevance of the final words caused by the hypnotic suggestion.

The influence of lexical word properties on selective attention to emotional words: Support for the attentional tuning of valent word forms

Using event-related potentials, it was found that selective attention to valence facilitates early affective discrimination of words with task-relevant valence and inhibits affective processing of words with task-irrelevant valence. This attention-based modulation of affective processing presumably relies on prior associative learning linking visual word forms with their affects. To investigate this hypothesis, we employed a valence-detection task and manipulated lexical (length, frequency) and affective (arousal) word features. Since we assumed that these features strongly influence the strength of visual form-affect associations, we expected them to play a crucial role in early affective discrimination. Fifty-eight participants made speeded responses only to words of one predefined target level of valence (negative, neutral, or positive), which varied across three blocks. As expected, the visual P1 component yielded greater valence discrimination for the target than for nontarget words. This interactive effect was most prominent for short, high-frequency and low-arousal words, respectively. Regarding the N170 component, low-frequency words showed higher amplitudes when they were either positive low-arousing or negative high-arousing compared with the other two sets of words, independently of target status. Additionally, an average-referenced EPN-like posterior negativity (150-270 ms) revealed a target-independent interaction between valence and arousal and increased amplitudes for negative target words. Results extend previous research in showing that particularly short and highly frequent valent word forms can be tuned by selective attention to valence, facilitating early affective discrimination. Finally, findings support the notion that valence and arousal interact during early preattentive, bottom-up processing which is interpreted within the valence-arousal conflict theory.

Laterality in Emotional Language Processing in First and Second Language

Language is a cognitive function that is asymmetrically distributed across both hemispheres, with left dominance for most linguistic operations. One key question of interest in cognitive neuroscience studies is related to the contribution of both hemispheres in bilingualism. Previous work shows a difference of both hemispheres for auditory processing of emotional and non-emotional words in bilinguals and monolinguals. In this study, we examined the differences between both hemispheres in the processing of emotional and non-emotional words of mother tongue language and foreign language. Sixty university students with Persian mother tongue and English as their second language were included. Differences between hemispheres were compared using the dichotic listening test. We tested the effect of hemisphere, language and emotion and their interaction. The right ear (associated with the left hemisphere) showed an advantage for the processing of all words in the first language, and positive words in the second language. Overall, our findings support previous studies reporting left-hemispheric dominance in late bilinguals for processing auditory stimuli.

For better or for worse: differential effects of the emotional valence of words on children's recall

Recent research has revealed the widespread effects of emotion on cognitive functions and memory. However, the influence of emotional valence on verbal short-term memory remains largely unexplored, especially in children. This study measured the effect of emotional valence on word immediate serial recall in 4-6-year-old French children (N = 124). Results show a robust effect of emotional valence on recall performances and recall errors. More precisely, we observed a facilitating effect of the positive valence of words: it allows better performance and causes few recall errors. On the contrary, the data indicated a disruptive impact of negative word valence: the latter causes very low recall performance and is associated with a high proportion of recall errors. These findings add new evidence of the influence of emotion on children's verbal short-term memory. Our results are discussed in relation to current semantic and attentional explanations of the emotional enhancement of memory.