Hemispheric asymmetry of emotion words in a non-native mind: a divided visual field study

A short review on emotion processing: a lateralized network of neuronal networks

Emotions are valenced mental responses and associated physiological reactions that occur spontaneously and automatically in response to internal or external stimuli, and can influence our behavior, and can themselves be modulated to a certain degree voluntarily or by external stimuli. They are subserved by large-scale integrated neuronal networks with epicenters in the amygdala and the hippocampus, and which overlap in the anterior cingulate cortex. Although emotion processing is accepted as being lateralized, the specific role of each hemisphere remains an issue of controversy, and two major hypotheses have been proposed. In the right-hemispheric dominance hypothesis, all emotions are thought to be processed in the right hemisphere, independent of their valence or of the emotional feeling being processed. In the valence lateralization hypothesis, the left is thought to be dominant for the processing of positively valenced stimuli, or of stimuli inducing approach behaviors, whereas negatively valenced stimuli, or stimuli inducing withdrawal behaviors, would be processed in the right hemisphere. More recent research points at the existence of multiple interrelated networks, each associated with the processing of a specific component of emotion generation, i.e., its generation, perception, and regulation. It has thus been proposed to move from hypotheses supporting an overall hemispheric specialization for emotion processing toward dynamic models incorporating multiple interrelated networks which do not necessarily share the same lateralization patterns.

The influence of word valence on the right visual field advantage in the VHF paradigm: time to adjust the expectations

Previous studies found that valence and visual half-field have an influence on word reading: Words are processed more efficiently when they evoke positive feelings and when they appear in the right visual field. In the present study we tried to address previous (contradictory) reports of an interaction between valence and visual half-field.A group of 39 right-handed undergraduates completed a lexical decision task in their native language (Dutch). They responded to 300 trials with real words and 300 trials with non-words. Overall, participants responded more efficiently to positive words and there was a strong right visual field advantage. We did not find a significant interaction, however. Further analysis indicated that to find a replicable interaction between a stimulus characteristic and visual half-field, one requires much high numbers of participants and stimuli than done so far. Experimental power is particularly low when the interaction is not fully crossed (a right visual field advantage for one type of stimulus and an equally large left visual field advantage for the other type of stimulus). If such investment cannot be made, the outcome is likely to be ambiguous at best and deceiving at worst if only significant findings are published.

Cognitive inhibition and attentional biases in the affective go/no-go performance of depressed, suicidal populations

BACKGROUND

Although cognitive inhibition deficits and attentional biases have been associated with suicidality, these findings have not been consistently reported across samples. The aim of the current study was to further investigate these variables among participants with differing suicidal risk.

METHODS

We compared affective go/no-go performance in 100 depressed individuals with both current suicidal ideation and a prior history of attempted suicide, 100 depressed individuals with current suicidal ideation, but no history of attempted suicide, 100 suicide attempters without current depression or suicidal ideation, and 100 healthy controls.

RESULTS

Suicide ideators with a history of attempted suicide committed more commission errors during negative word trials than any other group. Additionally, suicide ideators with no attempt history made more commission errors than did controls and previous attempters. An interaction for group status and emotional word valence revealed that suicide ideators with a history of attempted suicide responded fastest to negative words and slowest to positive words. Suicide ideators without an attempt history displayed a similar, but less pronounced pattern. Whereas, controls and previous attempters responded more quickly to positively valenced words.

LIMITATIONS

The use of cross-sectional self-report data and inclusion of only female participants limits generalizability.

CONCLUSIONS

Cognitive dysfunctions were apparent in all suicide vulnerable subjects, but significantly greater in suicide ideators with a history of attempted suicide. Suicidal ideation may be associated with a processing bias and inhibitory deficit for negative, mood-congruent information. These findings increase our knowledge of cognitive impairment in suicidality and may potentially help improve intervention strategies.

The Distinctiveness of Emotion Words: Does It Hold for Foreign Language Learners? The Case of Arab EFL Learners

Empirical evidence has recently been provided for the distinctiveness of emotion words as compared to abstract and concrete words for monolinguals, calling for a reconsideration of the relation between emotion and language. The present study investigates whether the distinctiveness of emotion words among monolinguals holds for foreign language learners. To this end, three groups (n = 120 per group) of late Arabic-English bilinguals who learned English as a foreign language completed tasks including free recall, rating, and discrete word association. One group completed the tasks in Arabic while the other two groups, representing two levels of foreign language exposure, completed the tasks in English. Planned comparisons indicated the distinctiveness of emotion words in the participants' first and foreign languages in the free recall and rating tasks while no significant differences were found in the word association task. The results are discussed in light of the existing literature and relevant theoretical models.

Effects of Valence on Hemispheric Specialization for Emotion Word Processing

The use of emotion in language is a key element of human interactions and a rich area for cognitive research. The present study examined reactions to words of five types: positive emotion (e.g., happiness), negative emotion (e.g., hatred), positive emotion-laden (e.g., blessing), negative emotion-laden (e.g., prison), and neutral (e.g., chance). Words and nonwords were intermixed in a lexical decision task using hemifield presentation. Results revealed a general left hemisphere advantage. Overall, reaction times for positive words were faster than for negative or neutral words and this effect varied by hemifield of presentation. These results support a valence hypothesis of specialized processing in the left hemisphere of the brain for positive emotions and the right hemisphere for negative emotions.

Analysis of functional brain connections for positive-negative emotions using phase locking value

In this study, we investigate the brain networks during positive and negative emotions for different types of stimulus (audio only, video only and audio + video) in [Formula: see text], and [Formula: see text] bands in terms of phase locking value, a nonlinear method to study functional connectivity. Results show notable hemispheric lateralization as phase synchronization values between channels are significant and high in right hemisphere for all emotions. Left frontal electrodes are also found to have control over emotion in terms of functional connectivity. Besides significant inter-hemisphere phase locking values are observed between left and right frontal regions, specifically between left anterior frontal and right mid-frontal, inferior-frontal and anterior frontal regions; and also between left and right mid frontal regions. ANOVA analysis for stimulus types show that stimulus types are not separable for emotions having high valence. PLV values are significantly different only for negative emotions or neutral emotions between audio only/video only and audio only/audio + video stimuli. Finding no significant difference between video only and audio + video stimuli is interesting and might be interpreted as that video content is the most effective part of a stimulus.

The bilingual brain turns a blind eye to negative statements in the second language

Neurobilingualism research has failed to reveal significant language differences in the processing of affective content. However, the evidence to date derives mostly from studies in which affective stimuli are presented out of context, which is unnatural and fails to capture the complexity of everyday sentence-based communication. Here we investigated semantic integration of affectively salient stimuli in sentential context in the first- and second-language (L2) of late fluent Polish–English bilinguals living in the UK. The 19 participants indicated whether Polish and English sentences ending with a semantically and affectively congruent or incongruent adjective of controlled affective valence made sense while undergoing behavioral and electrophysiological recordings. We focused on the N400, a wave of event-related potentials known to index semantic integration. We expected N400 amplitude to index increased processing demands in L2 English comprehension and potential language–valence interactions to reveal differences in affective processing between languages. Contrary to our initial expectation, we found increased N400 for sentences in L1 Polish, possibly driven by greater affective salience of sentences in the native language. Critically, language interacted with affective valence, such that N400 amplitudes were reduced for English sentences ending in a negative fashion as compared to all other conditions. We interpreted this as a sign that bilinguals suppress L2 content embedded in naturalistic L2 sentences when it has negative valence, thus extending the findings of previous research on single words in clinical and linguistic research.

Estimates of functional cerebral hemispheric differences in monolingual and bilingual people who stutter: Visual hemifield paradigm

The relationship between stuttering and bilingualism to functional cerebral hemispheric processing was examined using a visual hemifield paradigm. Eighty native German speakers, half of whom were also proficient speakers of English as a second language (L2), were recruited. The participants were organised into four different groups according to speech status and language ability: 20 monolinguals who stutter, 20 bilinguals who stutter, 20 monolinguals who do not stutter, and 20 bilinguals who do not stutter. All participants completed a task involving selective identification of common objects simultaneously presented to both visual fields. Overall, an LVF advantage was observed across all groups with no significant group differences in regard to hemispheric asymmetry. However, both bilingual groups showed faster reaction times and fewer identification errors than the two monolingual groups. A prevailing finding was that bilingualism seems to offset deficits in executive functioning associated with stuttering. Hence, the results lend support to previous findings implicating the benefits of bilingualism.