The neural response to maternal stimuli: an ERP study

Emotional autobiographical memory retrieval in time domain

Autobiographical memory (AM) is an important psychological phenomenon that has significance for self-development and mental health. The psychological mechanisms of emotional AM retrieval and their association with individual emotional symptoms remain largely unclear in the literature. For this purpose, the current study provided cue words to elicit emotional AMs. Event-related potentials (ERPs) associated with the retrieval process of AMs were recorded and analyzed. We found that the ERP component N400 was sensitive to both emotional valence and retrieval state, such that its amplitude was larger for negative compared to positive AMs, and larger responses for unrecalled compared to recalled AMs. Further, the N400 amplitude in the positive recalled condition was correlated with individual difference in depression (measured by the Beck Depression Inventory). Another ERP component, the late positive potential (LPP), was also sensitive to emotional valence, such that its amplitude was larger (i.e., more positive-going) for positive compared to negative cues. No significant effect was observed on the early ERP components P1, N1, or P2. The current findings bring new understanding on the difference between positive and negative AMs retrieval in the time domain. Also, the importance of this difference to the individual level of depression is worth noting.

Boosting attachment security to cope with threats: Behavioral and ERPs findings

Attachment security describes a sense of safety and security felt by individuals and promotes mental health. The mechanism by which attachment security buffers against psychological threat remains unclear, however. Here, we explored how attachment security attenuates the response to threatening information using a signal detection theory (SDT) and event-related potentials (ERPs) approach. Participants were assigned to an attachment security priming condition or a control condition. After a priming procedure, behavioral data and electroencephalography (EEG) signals were recorded while participants categorized threatening and neutral pictures. Our behavioral results revealed that attachment security biased participant responses to categorizing the two types of pictures; participants in the control condition exhibited a tendency to categorize stimuli as threatening, whereas those in the attachment security condition tended to categorize stimuli as neutral. Meanwhile, attachment security priming modulated early attention processes, reflected by an increased P200. The findings reported here suggest that attachment security buffers against external threats by modulating individual response preferences, the effects of which manifest in the early stages of attentional processing.

Unravelling how low dominance in faces biases non-spatial attention

According to the Dual Dodel of Social Hierarchy, one pathway for attaining social status is through dominance (coercion and intimidation). High dominance stimuli are known to more readily attract eye gaze and social attention. However, when there is a competition for non-spatial attentional resources, low dominance stimuli show an advantage. This low dominance bias was hypothesised to occur due to either counter-stereotypicality or attention competition. Here, these two hypotheses were examined across two experiments using modified versions of the attentional blink paradigm, used to measure non-spatial attention, and manipulations of facial dominance in both males and females. The results support the attention competition theory, suggesting that low dominance stimuli have a consistently strong ability to compete for attentional resources. Unexpectedly, high dominance stimuli fluctuate between having a strong and weak ability to compete for the same resources. The results challenge the current understanding of how humans interact with status.

Effects of dominance and prestige based social status on competition for attentional resources

Social status can be attained through either dominance (coercion and intimidation) or prestige (skill and respect). Individuals high in either of these status pathways are known to more readily attract gaze and covert spatial attention compared to their low-status counterparts. However it is not known if social status biases allocation of attentional resources to competing stimuli. To address this issue, we used an attentional blink paradigm to explore non-spatial attentional biases in response to face stimuli varying in dominance and prestige. Results from a series of studies consistently indicated that participants were biased towards allocating attention to low- relative to high- dominance faces. We also observed no effects of manipulating prestige on attentional bias. We attribute our results to the workings of comparatively early processing stages, separate from those mediating spatial attention shifts, which are tuned to physical features associated with low dominance. These findings challenge our current understanding of the impact of social status on attentional competition.

Self-Reference Emerges Earlier than Emotion during an Implicit Self-Referential Emotion Processing Task: Event-Related Potential Evidence

Self-referential emotion refers to the process of evaluating emotional stimuli with respect to the self. Processes indicative of a self-positivity bias are reflected in electroencephalogram (EEG) signals at ~400 ms when the task does not require a discrimination of self from other. However, when distinguishing between self-referential and other-referential emotions is required, previous studies have shown inconsistent temporal dynamics of EEG signals in slightly different tasks. Based on the observation of early self–other discrimination, we hypothesized that self would be rapidly activated in the early stage to modulate emotional processing in the late stage during an implicit self-referential emotion. To test this hypothesis, we employed an implicit task in which participants were asked to judge the order of Chinese characters of trait adjectives preceded by a self (“I”) or other pronoun (“He” or “She”). This study aimed to explore the difference of social-related emotional evaluation from self-reference; the other pronoun was not defined to a specific person, rather it referred to the general concept. Sixteen healthy Chinese subjects participated in the experiment. Event-related potentials (ERPs) showed that there were self-other discrimination effects in the N1 (80–110 ms) and P1 (170–200 ms) components in the anterior brain. The emotional valence was discriminated in the later component of N2 (220–250 ms). The interaction between self-reference and emotional valence occurred during the late positive potential (LPP; 400–500 ms). Moreover, there was a positive correlation between response time (RT) and N1 in the self-reference condition based on the positive-negative contrast, suggesting a modulatory effect of the self-positivity bias. The results indicate that self-reference emerges earlier than emotion and then combines with emotional processing in an implicit task. The findings extend the view that the self plays a highly integrated and modulated role in self-referential emotion processing.

Attachment affects social information processing: Specific electrophysiological effects of maternal stimuli

Attachment is critical to each individual. It affects the cognitive-affective processing of social information. The present study examines how attachment affects the processing of social information, specifically maternal information. We assessed the behavioral and electrophysiological responses to maternal information (compared to non-specific others) in a Go/No-go Association Task (GNAT) with 22 participants. The results illustrated that attachment affected maternal information processing during three sequential stages of information processing. First, attachment affected visual perception, reflected by enhanced P100 and N170 elicited by maternal information as compared to others information. Second, compared to others, mother obtained more attentional resources, reflected by faster behavioral response to maternal information and larger P200 and P300. Finally, mother was evaluated positively, reflected by shorter P300 latency in a mother + good condition as compared to a mother + bad condition. These findings indicated that the processing of attachment-relevant information is neurologically differentiated from other types of social information from an early stage of perceptual processing to late high-level processing.