The interaction between pictures and words: evidence from positivity offset and negativity bias

Processing of emotional connotations in Chinese monomorphic and compound words reflected by the early posterior negativity

Writing stands as one of humanity's most profound inventions, facilitating the efficient sharing and transmission of vast amounts of information. Similar to images and facial expressions, visual (written) words possess the ability to evoke emotional connotations. Understanding how the brain perceives these emotional nuances encoded in highly symbolic visual words is a key focus of the emerging field of "affective neurolinguistics." At the core of this inquiry lies the examination of the early posterior negativity (EPN), an event-related potentials (ERPs) component peaking around 300 ms after stimulus onset in the occipitotemporal scalp region. EPN has consistently emerged in response to emotional stimuli, encompassing pictures, faces, and visual words. However, prior research has notably lacked observation of EPN in response to Chinese emotional words, raising questions about potential differences in emotional processing between Chinese and other languages. Given the logographic nature of the Chinese writing system and the prevalence of compound words in the Chinese lexicon, this study aims to explore whether the emotional processing of Chinese monomorphic and compound words elicits an EPN response. Two experiments were conducted: Experiment 1 utilized one-character words (monomorphic words), while Experiment 2 employed two-character words (compound words). Participants were assigned a go/no-go task, instructed to respond to unknown words (word recognition task) or blue stimuli (color decision task). Data analysis using a data-driven mass univariate approach revealed significant ERP differences between emotional and neutral words. Notably, the time course, scalp topography, and cortical generators of the difference ERP presented a characteristic EPN response in both experiments. These findings strongly support the notion that the processing of emotional connotations in both Chinese monomorphic and compound words is reflected by the EPN, paving the way for future research using EPN as an emotion-related ERP component for investigating emotional processing of Chinese words.

The role of valence, arousal, stimulus type, and temporal paradigm in the effect of emotion on time perception: A meta-analysis

Anecdotal experiences show that the human perception of time is subjective, and changes with one's emotional state. Over the past 25 years, increasing empirical evidence has demonstrated that emotions distort time perception and usually result in overestimation. Yet, some inconsistencies deserve clarification. Specifically, it remains controversial how valence (positive/negative), arousal (high/low), stimulus type (scenic picture/facial expression/word/sound), and temporal paradigm (reproduction/estimation/discrimination) modulate the effect of emotion on time perception. Thus, the current study aimed to conduct a meta-analysis to quantify evidence for these moderators. After searching the Web of Science, SpiScholar, and Google Scholar, 95 effect sizes from 31 empirical studies were calculated using Hedges'g. The included studies involved 3,776 participants. The results a highlighted significant moderating effect of valence, arousal, stimulus type, and temporal paradigm. Specifically, negative valence tends to result in overestimation relative to positive valence; the increasing arousal leads to increasing temporal dilating; scenic picture, facial picture, and sound are more effective in inducing distortions than word; the overestimation can be better observed by discrimination and estimation paradigms relative to reproduction paradigms, and estimation paradigm is likely to be the most effective. These results suggest that the effect of emotion on time perception is influenced by valence, arousal, stimulus type, and temporal paradigm. These mitigating factors should be considered by scientists when studying time perception.

Evidence for dynamic attentional bias toward positive emotion-laden words: A behavioral and electrophysiological study

There has been no consensus on the neural dissociation between emotion-label and emotion-laden words, which remains one of the major concerns in affective neurolinguistics. The current study adopted dot-probe tasks to investigate the valence effect on attentional bias toward Chinese emotion-label and emotion-laden words. Behavioral data showed that emotional word type and valence interacted in attentional bias scores with an attentional bias toward positive emotion-laden words rather than positive emotion-label words and that this bias was derived from the disengagement difficulty in positive emotion-laden words. In addition, an attentional bias toward negative emotion-label words relative to positive emotion-label words was observed. The event-related potential (ERP) data demonstrated an interaction between emotional word type, valence, and hemisphere. A significant hemisphere effect was observed during the processing of positive emotion-laden word pairs rather than positive emotion-label, negative emotion-label, and negative emotion-laden word pairs, with positive emotion-laden word pairs eliciting an enhanced P1 in the right hemisphere as compared to the left hemisphere. Our results found a dynamic attentional bias toward positive emotion-laden words; individuals allocated more attention to positive emotion-laden words in the early processing stage and had difficulty disengaging attention from them in the late processing stage.

Emotional bias varies with stimulus type, arousal and task setting: Meta-analytic evidences

Emotional bias, which describes human's asymmetric processing of emotional stimuli, consists of negativity bias (Increased response to negative over positive stimuli) and positivity offset (the reversed phenomenon). Previous studies suggest that stimulus arousal (high/low), stimulus type (scenic/verbal), cultural background (Eastern/Western), and task setting (explicit/implicit) may modulate emotional bias, but with inconclusive findings. To address how the profile of emotional bias varies with these factors, a meta-analysis of emotional P3 event-related potential amplitudes was performed. Forty-nine effect sizes from 38 studies involving 1263 subjects were calculated using Hedges'g. The results highlight significant moderators of arousal, stimulus type, and task setting. Specifically, high-arousal stimuli enhance negativity bias relative to low-arousal stimuli; scenic stimulus leads to a negativity bias while verbal stimulus is linked with a positivity offset; explicit emotion tasks lead to negativity bias, whereas implicit emotion tasks do not exhibit emotional bias. These results indicate that emotional bias is labile depending on stimulus arousal, stimulus type and task setting. The implication of these findings for emotion regulation is discussed.

What's the meaning of this? A behavioral and neurophysiological investigation into the principles behind the classification of visual emotional stimuli

Two experiments were performed to investigate the principles by which emotional stimuli are classified on the dimensions of valence and arousal. In Experiment 1, a large sample of healthy participants rated emotional stimuli according to both broad dimensions. Hierarchical cluster analyses performed on these ratings revealed that stimuli were clustered according to their semantic content at the beginning of the agglomerative process. Example semantic themes include food, violence, nudes, death, and objects. Importantly, this pattern occurred in a parallel fashion for ratings on both dimensions. In Experiment 2, we investigated if the same semantic clusters were differentiated at the neurophysiological level. Intracerebral EEG was recorded from 18 patients with intractable epilepsy who viewed the same set of stimuli. Not only did electrocortical responses differentiate between these data-defined semantic clusters, they converged with the behavioral measurements to highlight the importance of categories associated with survival and reproduction. These findings provide strong evidence that the semantic content of affective material influences their classification along the broad dimensions of valence and arousal, and this principle of categorization exerts an effect on the evoked emotional response. Future studies should consider data-driven techniques rather than normative ratings to identify more specific, semantically related emotional images.

Positive words or negative words: whose valence strength are we more sensitive to?

The present study investigates the human brains' sensitivity to the valence strength of emotionally positive and negative chinese words. Event-Related Potentials were recorded, in two different experimental sessions, for Highly Positive (HP), Mildly Positive (MP) and neutral (NP) words and for Highly Negative (HN), Mildly Negative (MN) and neutral (NN) words, while subjects were required to count the number of words, irrespective of word meanings. The results showed a significant emotion effect in brain potentials for both HP and MP words, and the emotion effect occurred faster for HP words than MP words: HP words elicited more negative deflections than NP words in N2 (250-350 ms) and P3 (350-500 ms) amplitudes, while MP words elicited a significant emotion effect in P3, but not in N2, amplitudes. By contrast, HN words elicited larger amplitudes than NN words in N2 but not in P3 amplitudes, whereas MN words produced no significant emotion effect across N2 and P3 components. Moreover, the size of emotion-neutral differences in P3 amplitudes was significantly larger for MP compared to MN words. Thus, the human brain is reactive to both highly and mildly positive words, and this reactivity increased with the positive valence strength of the words. Conversely, the brain is less reactive to the valence of negative relative to positive words. These results suggest that human brains are equipped with increased sensitivity to the valence strength of positive compared to negative words, a type of emotional stimuli that are well known for reduced arousal.

The adaptation of the Affective Norms for English Words (ANEW) for European Portuguese

This study presents the adaptation of the Affective Norms for English Words (ANEW; Bradley & Lang, 1999a) for European Portuguese (EP). The EP adaptation of the ANEW was based on the affective ratings made by 958 college students who were EP native speakers. Subjects assessed about 60 words by considering the affective dimensions of valence, arousal, and dominance, using the Self-Assessment Manikin (SAM) in either a paper-and-pencil or a Web survey procedure. Results of the adaptation of the ANEW for EP are presented. Furthermore, the differences between EP, American (Bradley & Lang, 1999a), and Spanish (Redondo, Fraga, Padrón, & Comesaña, Behavior Research Methods, 39, 600-605, 2007) standardizations were explored. Results showed that the ANEW words were understood in a similar way by EP, American, and Spanish subjects, although some sex and cross-cultural differences were observed. The EP adaptation of the ANEW is shown to be a valid and useful tool that will allow researchers to control and/or manipulate the affective properties of stimuli, as well as to develop cross-linguistic studies. The normative values of EP adaptation of the ANEW can be downloaded at http://brm.psychonomic-journals.org/content/supplemental .

The influence of background music on recognition processes of Chinese characters: an ERP study

In this paper, we employed RSS (rapid stream stimulation) paradigm to study the recognition processes of Chinese characters in background music. Real Chinese characters (upright or rotated) were used as target stimuli, while pseudo-words were used as background stimuli. Subjects were required to detect real characters while listening to Mozart's Sonata K. 448 and in silence. Both behavioral results and ERP results supported that Mozart's music mainly served as a distracter in the recognition processes of real Chinese characters in the experiment. The modulation of Mozart's music on RP (recognition potential) was different across different orientations of Chinese characters; in particular, the modulation of RP elicited by upright Chinese characters was more significant, suggesting that the music factor and orientation factor interact to affect the RP component. In brief, the simultaneous playing of Mozart's music did not improve subjects' performance in the detection of real Chinese characters.

Semantic association of ecologically unrelated synchronous audio-visual information in cognitive integration: an event-related potential study

In this paper, we aimed to study the semantic association of ecologically unrelated synchronous audio-visual information in cognitive integration. A moving particle, which speed varied, was taken as a visual stimulus, while a simple tone, which frequency varied, was used as an auditory stimulus, both were synchronously presented to subjects in the form of a video. Behavioral results confirmed our hypothesis that the moving particle with varied speed and the simple tone with varied frequency were highly associated. Event-related potential (ERP) results showed that an N400 effect and a late posterior negativity (LPN) were elicited under the Incongruent condition as compared to the Congruent condition. It was further determined that there was semantic association between ecologically unrelated synchronous audio-visual information in cognitive integration. We considered that the N400 effect in our results reflected the process that stimulus-driven activities are bound together through a temporal semantic network (TSN) to form multimodal representations, while the state of this temporal semantic network was determined by both long-term learned association among stimuli and short-term experience of incoming information. The LPN might reflect the process that the human brain searches and retrieves context-specifying information in order to make a judgment, and the context-specifying information might have originated from the long-term learned association stored in the brain.

Emotional words impact the mind but not the body: evidence from pupillary responses

Pupillary responses have been shown to be sensitive to both task load and emotional content. We investigated the interplay of these factors in the processing of single words that varied in emotional valence and arousal. Two tasks of different cognitive load, uninstructed reading and a lexical decision task, were employed, followed by an unannounced recognition task. Reaction times were faster and incidental memory performance was better for high-arousing than for low-arousing words. In contrast to previous findings for pictures and sounds, high-arousing words elicited smaller pupillary responses than low-arousing words; these effects were independent of task load, which increased pupil diameter. Therefore, emotional arousal attributed to words does not mandatorily activate the autonomic nervous system, but rather works on a cognitive level, facilitating word processing.

Self-reference modulates the processing of emotional stimuli in the absence of explicit self-referential appraisal instructions

Self-referential evaluation of emotional stimuli has been shown to modify the way emotional stimuli are processed. This study aimed at a new approach by investigating whether self-reference alters emotion processing in the absence of explicit self-referential appraisal instructions. Event-related potentials were measured while subjects spontaneously viewed a series of emotional and neutral nouns. Nouns were preceded either by personal pronouns ('my') indicating self-reference or a definite article ('the') without self-reference. The early posterior negativity, a brain potential reflecting rapid attention capture by emotional stimuli was enhanced for unpleasant and pleasant nouns relative to neutral nouns irrespective of whether nouns were preceded by personal pronouns or articles. Later brain potentials such as the late positive potential were enhanced for unpleasant nouns only when preceded by personal pronouns. Unpleasant nouns were better remembered than pleasant or neutral nouns when paired with a personal pronoun. Correlation analysis showed that this bias in favor of self-related unpleasant concepts can be explained by participants' depression scores. Our results demonstrate that self-reference acts as a first processing filter for emotional material to receive higher order processing after an initial rapid attention capture by emotional content has been completed. Mood-congruent processing may contribute to this effect.

Cognitive processing of traffic signs in immersive virtual reality environment: An ERP study

The virtual reality environment can provide an immersive feeling as in the real word. So, using virtual reality technology to construct realistic experimental scenarios, the mechanism of cognitive processing in the human brain could be better studied. In this paper, we have designed an experiment, where through the presentation of traffic signs with correct or incorrect background colors in a virtual reality traffic environment, and studied the cognitive processing in the human brain using event-related potential (ERP) method. The results showed that whether the background colors of traffic signs were correct or not, the degrees of familiarity to these traffic signs in the human brain were similar, and the degree of contrast between the background colors and foreground colors of traffic signs would influence the degree of difficulty in cognitive processing. The degree of complexity in contents of traffic signs appears related to the cognitive speed in the human brain. In sum, simpler contents and larger contrast between the background colors and foreground colors of traffic signs would make the human brain respond faster.