Filial versus romantic love: contributions from peripheral and central electrophysiology

A major problem in recent neuroscience research on the processing of loved familiar faces is the absence of evidence concerning the elicitation of a genuine positive emotional response (love). These studies have two confounds: familiarity and arousal. The present investigation controlled for both factors in female university students. Two categories of loved faces were chosen: one with higher familiarity but lower emotionality (fathers) and the other with higher emotionality but lower familiarity (romantic partners). Unfamiliar and baby faces were used as control faces. Central and peripheral electrophysiological measures as well as subjective indices of valence, arousal, and dominance were recorded. Results support the conclusion that viewing loved familiar faces elicits an intense positive emotional reaction that cannot be explained either by familiarity or arousal. The differences between romantic and filial love appeared in the magnitude of some peripheral and subjective indices of emotionality (zygomatic activity, valence, arousal, and dominance), that were higher for images of the romantic partners, and one central index of familiarity (the P3 amplitude), that was higher for images of the fathers.     

Positive emotional reactions to loved names

Studies concerning personal attachment have successfully used loved familiar faces to prompt positive affective and physiological reactions. Moreover, the processing of emotional words shows similar physiological patterns to those found with affective pictures. The objective of this study was to assess whether the passive viewing of loved names would produce a pattern of subjective and physiological reactivity similar to that produced by the passive viewing of loved faces. The results showed that, compared to neutral (unknown) and famous names, loved names produced a biphasic pattern of heart rate deceleration‐acceleration, heightened skin conductance and zygomaticus muscle activity, inhibition of corrugator muscle activity, and potentiation of the startle reflex response. This pattern of physiological responses was accompanied by subjective reports of higher positive affect and arousal for loved names than for neutral and famous ones. These findings highlight not only the similarity but also the differences between the affective processing of identity recognition by loved faces and names.     

Event-related potential responses to love-related facial stimuli

In event-related potential (ERPs) studies, emotional stimuli usually elicit an enhanced late positive potential (LPP), which is assumed to reflect motivated attention. However, whether a stimulus elicits emotional responses may depend on the individual's state, such as experiencing romantic love. It has been suggested that stimuli that are related to someone's beloved will elicit increased attention in that infatuated individual. In this study, participants who were in love viewed faces of their beloved, their friend, and of an unknown, beautiful person. The friend was included to control for familiarity, and the unknown person for perceived beauty. As expected, the LPP was larger in response to the face of the beloved than to the other two emotionally significant faces. Interpreting the LPP as reflecting motivated attention, this implies that romantic love is accompanied by increased attention for the face of one's beloved.     

Modulatory effects of emotion and sleep on recollection and familiarity

Growing evidence suggests that declarative memory benefits from the modulatory effects of emotion and sleep. The primary goal of the present study was to determine whether these two factors interact to enhance memory or they act independently of each other. Twenty-eight volunteers participated in the study. Half of them were sleep deprived the night immediately following the exposure to emotional and non-emotional images, whereas the control group slept at home. Their memory for images was tested 1 week later along the valence and arousal dimension of emotion with the remember–know procedure. As emotional events appear to gain preference during encoding, via the modulatory effect of amygdala on prefrontal and medial temporal lobe regions, conscious retrieval of emotional pictures (relative to neutral ones) was expected to be less disrupted by sleep loss. Results indicated that emotional images were more richly experienced in memory than neutral, particularly those with high arousal and positive valence. Even though sleep deprivation resulted in behavioral impairment at retrieval of both emotional and neutral images, results revealed that remember-based recognition accuracy and its underlying process of recollection for emotional images were less influenced by the lack of sleep (the mean difference between control and sleep-deprived subjects was around 40% higher for neutral images than for emotional images). Familiarity, however, was affected by neither emotion nor sleep. Taken together, these results suggest that emotion and sleep influence differentially the subjective experience of remembering and knowing and the underlying processes of recollection and familiarity through brain mechanisms probably involving amygdala- and hippocampo-neocortical networks respectively.     

成语情感词分类系统的初步建立

目的建立一套情绪障碍研究用中华成语情感词分类系统,为异常情绪的研究提供标准化刺激材料。方法 65名不同文化程度的被试对345个中华成语情绪词（包括115个正性词、115个负性词、115个中性词）的愉悦度、唤醒度、优势度、熟悉度、使用频率、情绪性、模糊性、形象性8个维度进行9级的等级评定。结果 3类词语在3个维度上的ANOVA结果显示,分别存在愉悦度主效应（F=624.708,P〈0.01）、唤醒度主效应（F=384.826,P〈0.01）、优势度主效应（F=408.984,P〈0.01）、熟悉度主效应（F=21.542,P〈0.01）、使用频率主效应（F=24.128,P〈0.01）、情绪性主效应（F=607.882,P〈0.01）、模糊性主效应（F=54.276,P〈0.01）和形象性主效应（F=53.947,P〈0.01）。重复测量方差分析结果表明3类词语在8个维度上组间效应（F=891.641,P〈0.01）和组内效应（F=20164.989,P〈0.01）均有统计学意义。结论此次初步建立的中华成语情感词分类系统较好,为以后异常情绪的研究提供情感词语刺激材料。     

Healthy aging is associated with increased neural processing of positive valence but attenuated processing of emotional arousal: an fMRI study

Arousal and valence play key roles in emotional perception, with normal aging leading to changes in the neural substrates supporting valence processing. The objective of this study was to investigate normal age-related changes in the neural substrates of emotional arousal processing. Twenty-three young and 23 older, healthy women underwent functional magnetic resonance imaging as they viewed images which were neutral or positive in valence and which varied in arousal level from low to high. Using a parametric modulation approach, we examined how the blood oxygen-level dependent signal varied with single trial subjective ratings of valence and arousal, and whether this differed with age. In accordance with previous studies we found that the older group showed greater activation in response to positive valence, in the left amygdala, left middle temporal gyrus and right lingual gyrus. In contrast however, they showed reduced reactivity to emotional arousal, in occipital and temporal visual cortices bilaterally, the left inferior parietal cortex, and the supplementary motor area bilaterally. This study represents the first of its kind to clearly dissociate how aging affects the neural correlates of emotional arousal and valence. The changes in arousal processing may in part be mediated by the functional reorganization evident in the aging brain, such as reduced activation of the posterior cortices as described by the posterior-anterior shift in ageing (PASA) effect.     

Subjective and physiological responses to emotion-eliciting pictures in male schizophrenic patients.

Several studies have shown that schizophrenic patients have difficulties in their ability to recognize emotional facial expressions, whereas other research indicated that they subjectively report the same emotional experience as healthy controls. The purpose of this study was to investigate whether the physiological responses that accompany emotions differ between schizophrenic patients and controls, which would suggest a different basic emotional processing mechanism in these patients. We presented 40 emotion-eliciting pictures to male patients (n=26) and controls (n=21), while measuring heart rate (HR), breathing rate (BR), skin conductance response (SCR) and systolic blood pressure (SBP). Each subject rated each picture for its degree of valence and arousal. Mixed-effects regression models were used to investigate the relationships between the subjective ratings and the physiological responses. In both groups, BR and SCR increased with increasing arousal ratings, suggesting sympathetic activation. The SBP of both groups increased with increases in both the valence and the arousal ratings. However, whereas the patients' HR first decreased with decreasing pleasure ratings and subsequently increased with higher arousal and valence ratings, the HR in the control group was influenced by a complex interaction between valence and arousal ratings. Thus, the schizophrenic patients showed similar relationships between subjective ratings and SCR, BR, and SBP, but a different relationship between subjective ratings and HR compared with the healthy controls.     

Pay attention to me! Late ERPs reveal gender differences in attention allocated to romantic partners

The present study employed late ERPs to examine differences in the association between neural responses to romantic partners and relationship quality factors across men and women. Participants passively viewed photos of their romantic partners, celebrities, and strangers during a computerized facial processing task. All participants demonstrated enhanced positivity to partner faces at late ERP components (P3 and LPP), furthering the notion that significant others elicit more motivated and sustained attention than do other familiar or unfamiliar individuals. Neural responses to romantic partner faces were influenced by factors including overall relationship quality, investment, and communication quality, with associations varying by gender. Results highlight the key role that relationship quality factors play in the immediate processing of romantic partners—a finding with implications for couples counseling and research.     

Respiratory sinus arrhythmia as an index of emotional response in young adults

The relationship between respiratory sinus arrhythmia (RSA) and valence and arousal remains unclear. In the present study, the associations between emotion responses and tonic or task-related changes in RSA were assessed. Specifically, the sensitivities of changes in interbeat interval, RSA, and skin conductance to the valence and arousal values of emotional stimuli were examined. This study also explored the association between tonic RSA and subjective, expressive, and physiological emotional responses. Response measures were collected from 56 adults during baseline and film-viewing periods. Tonic RSA was not significantly related to any of the response measures. Increased skin conductance and decreased RSA were associated with arousal independent of valence. Interbeat interval was related to affective valence and not arousal. These findings suggest that RSA may be a useful adjunct to skin conductance measures in assessing emotional arousal.     

A startling absence of emotion effects: Active attention to the startle probe as a motor task cue appears to eliminate modulation of the startle reflex by valence and arousal

Research has shown that during emotional imagery, valence and arousal each modulate the startle reflex. Here, two imagery-startle experiments required participants to attend to the startle probe as a simple reaction time cue. In Experiment 1, four emotional conditions differing in valence and arousal were examined. Experiment 2, to accentuate potential valence effects, included two negative high arousal, a positive high arousal and a negative low arousal condition. Imagery effectively manipulated emotional valence and arousal, as indicated by heart rate and subjective ratings. Compared to baseline, imagery facilitated startle responses. However, valence and arousal failed to significantly affect startle magnitude in both experiments and startle latency in Experiment 1. Results suggest that emotional startle modulation is eclipsed when the probe is significant for task completion and/or cues a motor response. Findings suggest that an active, rather than defensive, response set may interfere with affective startle modulation, warranting further investigation.     

情绪障碍研究用汉语情绪词分类系统的初步建立

目的：建立一套情绪障碍研究用汉语情绪词分类系统，为异常情绪的研究提供标准化刺激材料。方法：54名不同受教育程度的被试对344个双字汉语情绪词（包括115个正性词、114个负性词、115个中性词）的愉悦度、唤醒度和熟悉度三个维度进行9级的情绪等级评定。结果：三类词语在三个维度上的ANOVA结果显示，分别存在愉悦度主效应（F=2514．96，P=0．000）、唤醒度主效应（F=147．43，P=0．000）和熟悉度主效应（F=106．81，P=0．000）。两两比较后发现正性词的愉悦度得分（7．29±0．41）高于负性和中性词（2．81±0．30、5．47±0．66），中性词得分高于负性词；正性词的唤醒度得分（6．57±0．39）高于负性词和中性词（5．33±0．41、5．23±0．67）；正性词的熟悉度得分（5．98±0．57）高于负性和中性词（4．63±0．53、5．21±0．93），中性词得分高于负性词。结论：初步建立的情绪障碍研究用汉语情绪词分类系统较好，为以后的异常情绪的研究提供词语刺激材料。     

Sex differences in memory of emotional images: a behavioral and electrophysiological investigation

Current research suggests that emotional responses differ between men and women. Sex differences regarding emotional effects on memory have been recently studied through brain imaging techniques. However, the majority of investigations have often neglected to balance the variable of emotional intensity (arousal) across pleasant and unpleasant pictures. Additionally, men and women were often mixed or studied separately. The current study aims at comparing men and women's electrophysiological responses related to emotional memory of photographic material. These responses were measured using Event Related brain Potentials (ERP) in response to a task of episodic memory of emotional images. The frontal N200, the parietal P300 and the central LPC were compared in 17 men and 17 women matched for age, social economic status, education and intelligence. Behavioral results showed that, in men, reaction times were modulated by valence, whereas for women, reaction times were mainly modulated by arousal. Accuracy was affected by both emotional valence and arousal, but only in women. ERP analyses revealed that emotional valence influenced earlier time components (frontal N200 and parietal P300), whereas arousal influenced memory in the later time component (central LPC). Moreover, sex differences, mediated by valence and arousal, were found in ERP responses at different times in the processing stream.     

Interaction of facial expressions and familiarity: ERP evidence

There is mounting evidence that under some conditions the processing of facial identity and facial emotional expressions may not be independent; however, the nature of this interaction remains to be established. By using event-related brain potentials (ERP) we attempted to localize these interactions within the information processing system. During an expression discrimination task (Experiment 1) categorization was faster for portraits of personally familiar vs. unfamiliar persons displaying happiness. The peak latency of the P300 (trend) and the onset of the stimulus-locked LRP were shorter for familiar than unfamiliar faces. This implies a late perceptual but pre-motoric locus of the facilitating effect of familiarity on expression categorization. In Experiment 2 participants performed familiarity decisions about portraits expressing different emotions. Results revealed an advantage of happiness over disgust specifically for familiar faces. The facilitation was localized in the response selection stage as suggested by a shorter onset of the LRP. Both experiments indicate that familiarity and facial expression may not be independent processes. However, depending on the kind of decision different processing stages may be facilitated for happy familiar faces.     

中国面部表情视频系统的初步建立

目的：建立本土化的中国面部表情视频系统（ehinese facial expression video system，CFEVS）以增加情绪研究的取材范围。方法：录制强度分为三等级的喜悦、悲伤、惊奇、恐惧、愤怒、厌恶及中性（无表情及咀嚼动作两种）等面部表情视频片段，经两轮粗选后，请50名中国大学生对剩余视频片段的表情类型、愉悦度、唤醒度及表演者的长相进行自我报告式评定。将表情类型、愉悦度、唤醒度一致性高且表情类型与愉悦度相一致的片段纳入CFEVS，做分布分析，同时分析评测者性别、表演者长相对愉悦度、唤醒度分值的影响。结果：纳入CFEVS的喜悦表情男18女43共61个，悲伤表情男23女28共51个，无表情中性男13女17共31个，咀嚼中性男7女17共24个。散点图显示CFEVS在愉悦度及唤醒度上分布较为广泛。方差分析表明评测者性别及表演者长相对视频片段的愉悦度、唤醒度的影响与其表情类型有关。结论：本研究初步建立了一个拥有喜悦、悲伤及中性表情的CFEVS，并发现评测者的性别及表演者的长相可影响实验结果。     

Detecting a viewer’s familiarity with a face: Evidence from event-related brain potentials and classifier analyses

Human observers recognize the faces of people they know efficiently and without apparent effort. Consequently, recognizing a familiar face is often assumed to be an automatic process beyond voluntary control. However, there are circumstances in which a person might seek to hide their recognition of a particular face. The present study therefore used event-related potentials (ERPs) and a classifier based on logistic regression to determine if it is possible to detect whether a viewer is familiar with a particular face, regardless of whether the participant is willing to acknowledge it or not. In three experiments, participants were presented with highly variable “ambient” images of personally familiar and unfamiliar faces, while performing an incidental butterfly detection task (Experiment 1), an explicit familiarity judgment task (Experiment 2), and a concealed familiarity task in which they were asked to deny familiarity with one truly known facial identity while acknowledging familiarity with a second known identity (Experiment 3). In all three experiments, we observed substantially more negative ERP amplitudes at occipito-temporal electrodes for familiar relative to unfamiliar faces starting approximately 200 ms after stimulus onset. Both the earlier N250 familiarity effect, reflecting visual recognition of a known face, and the later sustained familiarity effect, reflecting the integration of visual with additional identity-specific information, were similar across experiments and thus independent of task demands. These results were further supported by the classifier analysis. We conclude that ERP correlates of familiar face recognition are largely independent of voluntary control and discuss potential applications in forensic settings.     

国际情绪图片系统的本土化研究:在中国大学生群体中的评定

目的:国际情绪图片系统(LAPS)是美国情绪与注意研究中心为情绪相关研究编制的标准化图片系统.但其各项参数尚未在中国人群中得以完整地评定与验证.方法:本研究选取中国大学生被试300名,对全部704张LAPS图片从效价、唤醒度、优势度三个维度进行了中国本土化评定.结果:中国被试评定虽然与LAPS原始评分具有较高的相关,但是在效价与唤醒度维度上均具有显著的差异;对于与中国文化特征相冲突的强烈、直接的情绪图片.中国被试在效价方面的评分显著低于原始结果,而唤醒度高于原始评定.结论:IAPS图片虽然具有较好的国际适用性,但虑及东西方文化差异,中国研究中应参考本土评定结果选取相关的LAPS图片.     

考试焦虑图片库的编制:在中国大学生群体中的试用

目的:建立标准的考试焦虑图片库以适应考试焦虑研究的需要。方法:筛选出210张图片组成考试焦虑图片库,62名中国大学生对所有图片的愉悦度、唤醒度和优势度进行了自我报告的9点量表评分,并对图片与考试是否相关做3点量表评分。结果:62名被试对210幅图片的评分结果在四个维度上的内部一致性信度系数、分半信度都高于0.90。与考试相关图片的唤醒度高于无关图片,而愉悦度、优势度则低于无关图片。聚类分析将图片分为六类,各类图片在四个维度评分的差异显著(P<0.001)。组间比较显示,除在相关图片优势度上焦虑组间差异显著外,其他均不显著。结论:考试焦虑图片库具有良好的信度和效度,评分结果可靠而稳定,可用于有关考试焦虑的研究。     

Different brain activity in response to emotional faces alone and augmented by contextual information

This study examined the extent to which emotional face stimuli differ from the neural reactivity associated with more ecological contextually augmented stimuli. Participants were scanned when they viewed contextually rich pictures depicting both emotional faces and context, and pictures of emotional faces presented alone. Emotional faces alone were more strongly associated with brain activity in paralimbic and social information processing regions, whereas emotional faces augmented by context were associated with increased and sustained activity in regions potentially representing increased complexity and subjective emotional experience. Furthermore, context effects were modulated by emotional intensity and valence. These findings suggest that cortical elaboration that is apparent in contextually augmented stimuli may be missed in studies of emotional faces alone, whereas emotional faces may more selectively recruit limbic reactivity.     

The effects of inversion and eye displacements of familiar and unknown faces on early and late-stage ERPs.

OBJECTIVES: The objective of this study is to examine whether configural alterations of faces affect early or late processing stages as a function of their familiarity and their level of representation in memory. We then sought to verify whether the structural encoding stage is susceptible to top-down influences. METHODS: Electrophysiologic and behavioral studies were undertaken, during which unknown and familiar faces were presented upright or upside-down with or without feature alterations. The subjects were asked to determine whether the faces were familiar or not. RESULTS: N170 and N360 amplitudes were larger for familiar faces as well as altered ones. A higher degree of familiarity decreased reaction times (RTs) and N360 latencies, but increased N170 latencies, whereas face alterations increased RTs and latencies of both components examined. However, familiarity interacted with altered face configurations only for RTs and the N170. SIGNIFICANCE: In the perceptual stage, familiar faces seem to develop a more elaborate type of processing because of top-down influences linked to the robust nature of their representations in memory. The more elaborate type of processing for familiar faces has advantageous consequences for the following steps of information processing, by facilitating access to structural representations in memory (N360) as well as the final step reflected by RTs. The fact that configural alterations cause different effects for familiar as opposed to unfamiliar faces indicate that these stimuli are processed in a qualitatively different manner and solicit different representations in memory.     

Electrocortical processing of social signals of threat in combat-related post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is characterized by avoidance, emotional numbing, increased arousal and hypervigilance for threat following a trauma. Thirty-three veterans (19 with PTSD, 14 without PTSD) who had experienced combat trauma while on deployment in Iraq and/or Afghanistan completed an emotional faces matching task while electroencephalography was recorded. Vertex positive potentials (VPPs) elicited by happy, angry and fearful faces were smaller in veterans with versus without PTSD. In addition, veterans with PTSD exhibited smaller late positive potentials (LPPs) to angry faces and greater intrusive symptoms predicted smaller LPPs to fearful faces in the PTSD group. Veterans with PTSD were also less accurate at identifying angry faces, and accuracy decreased in the PTSD group as hyperarousal symptoms increased. These findings show reduced early processing of emotional faces, irrespective of valence, and blunted prolonged processing of social signals of threat in conjunction with impaired perception for angry faces in PTSD.