情绪和时间辨别任务中视听整合与预先准备效应

本研究分别在时间和情绪认知维度上考察预先准备效应对情绪视听整合的影响。时间辨别任务(实验1)发现视觉引导显著慢于听觉引导,并且整合效应量为负值。情绪辨别任务(实验2)发现整合效应量为正值;在负性情绪整合中,听觉引导显著大于视觉引导;在正性情绪整合中,视觉引导显著大于听觉引导。研究表明,情绪视听整合基于情绪认知加工,而时间辨别会抑制整合;此外,跨通道预先准备效应和情绪预先准备效应都与引导通道有关。     

Is there an advantage for recognizing multi-modal emotional stimuli?

Emotions can be recognized whether conveyed by facial expressions, linguistic cues (semantics), or prosody (voice tone). However, few studies have empirically documented the extent to which multi-modal emotion perception differs from uni-modal emotion perception. Here, we tested whether emotion recognition is more accurate for multi-modal stimuli by presenting stimuli with different combinations of facial, semantic, and prosodic cues. Participants judged the emotion conveyed by short utterances in six channel conditions. Results indicated that emotion recognition is significantly better in response to multi-modal versus uni-modal stimuli. When stimuli contained only one emotional channel, recognition tended to be higher in the visual modality (i.e., facial expressions, semantic information conveyed by text) than in the auditory modality (prosody), although this pattern was not uniform across emotion categories. The advantage for multi-modal recognition may reflect the automatic integration of congruent emotional information across channels which enhances the accessibility of emotion-related knowledge in memory.     

Cortical operational synchrony during audio-visual speech integration

Information from different sensory modalities is processed in different cortical regions. However, our daily perception is based on the overall impression resulting from the integration of information from multiple sensory modalities. At present it is not known how the human brain integrates information from different modalities into a unified percept. Using a robust phenomenon known as the McGurk effect it was shown in the present study that audio-visual synthesis takes place within a distributed and dynamic cortical networks with emergent properties. Various cortical sites within these networks interact with each other by means of so-called operational synchrony (Kaplan, Fingelkurts, Fingelkurts, & Darkhovsky, 1997). The temporal synchronization of cortical operations processing unimodal stimuli at different cortical sites reveals the importance of the temporal features of auditory and visual stimuli for audio-visual speech integration.     

Using eye-tracking to study audio-visual perceptual integration

Perceptual integration of audio-visual stimuli is fundamental to our everyday conscious experience. Eye-movement analysis may be a suitable tool for studying such integration, since eye movements respond to auditory as well as visual input. Previous studies have shown that additional auditory cues in visual-search tasks can guide eye movements more efficiently and reduce their latency. However, these auditory cues were task-relevant since they indicated the target position and onset time. Therefore, the observed effects may have been due to subjects using the cues as additional information to maximize their performance, without perceptually integrating them with the visual displays. Here, we combine a visual-tracking task with a continuous, task-irrelevant sound from a stationary source to demonstrate that audio-visual perceptual integration affects low-level oculomotor mechanisms. Auditory stimuli of constant, increasing, or decreasing pitch were presented. All sound categories induced more smooth-pursuit eye movement than silence, with the greatest effect occurring with stimuli of increasing pitch. A possible explanation is that integration of the visual scene with continuous sound creates the perception of continuous visual motion. Increasing pitch may amplify this effect through its common association with accelerating motion.     

基于视听双通道的音乐情绪加工机制及情绪类型和音乐经验的影响

为了探讨视听双通道下的音乐情绪加工机制及音乐情绪类型和音乐训练背景对加工机制的影响,本研究采用表达开心和悲伤的音乐表演视频为材料,比较音乐组被试和非音乐组被试在单听觉通道、单视觉通道和视听双通道三种情境下的情绪评定速度、正确率和强度。结果发现：1）视听双通道与单视觉通道差异显著,与单听觉通道差异不显著。2）非音乐组被试对悲伤的评定正确率高于音乐组被试,对开心的评定正确率低于音乐组被试。说明音乐情绪加工的视听双通道整合优势仅相对单视觉通道存在;非音乐组被试对视觉通道情绪信息的变化更敏感,音乐组被试更依赖音乐经验;可在音乐表演时加入协调的视觉通道情绪信息帮助没有音乐训练经验的听赏者。     

Eye position affects audio-visual fusion in darkness

We investigated the frame of reference involved in audio-visual (AV) fusion over space. This multisensory phenomenon refers to the perception of unity resulting from visual and auditory stimuli despite their potential spatial disparity. The extent of this illusion depends on the eccentricity in azimuth of the bimodal stimulus (Godfroy et al, 2003 Perception 32 1233-1245). In a previous study, conducted in a luminous environment, Roumes et al 2004 (Perception 33 Supplement, 142) have shown that variation of AV fusion is gaze-dependent. Here we examine the contribution of ego- or allocentric visual cues by conducting the experiment in total darkness. Auditory and visual stimuli were displayed in synchrony with various spatial disparities. Subjects had to judge their unity ('fusion' or 'no fusion'). Results showed that AV fusion in darkness remains gaze-dependent despite the lack of any allocentric cues and confirmed the hypothesis that the reference frame of the bimodal space is neither head-centred nor eye-centred.     

基于视听双通道的音乐情绪冲突效应及优势通道研究

为探讨基于视听双通道的音乐情绪冲突效应、冲突情境下的优势加工通道和音乐经验对结果的影响,本研究采用音乐表演视频为材料,比较音乐组和非音乐组被试在一致型和不一致型视听双通道下的情绪评定速度、准确性及强度。结果发现:(1)一致型条件下的情绪评定更准确且更强烈;(2)不一致型条件下,被试更多以听觉通道的情绪线索为依据进行情绪类型评定;(3)非音乐组被试比音乐组被试更依赖视觉通道的情绪线索。结果表明:通道间情绪信息的不一致阻碍了音乐情绪加工; 听觉通道是音乐情绪冲突情境下的优势加工通道; 音乐经验降低了情绪冲突效应对音乐组被试的干扰。     

Age-related decrease in recognition of emotional facial and prosodic expressions

The recognition of nonverbal emotional signals and the integration of multimodal emotional information are essential for successful social communication among humans of any age. Whereas prior studies of age dependency in the recognition of emotion often focused on either the prosodic or the facial aspect of nonverbal signals, our purpose was to create a more naturalistic setting by presenting dynamic stimuli under three experimental conditions: auditory, visual, and audiovisual. Eighty-four healthy participants (women = 44, men = 40; age range 20-70 years) were tested for their abilities to recognize emotions either mono- or bimodally on the basis of emotional (happy, alluring, angry, disgusted) and neutral nonverbal stimuli from voice and face. Additionally, we assessed visual and auditory acuity, working memory, verbal intelligence, and emotional intelligence to explore potential explanatory effects of these population parameters on the relationship between age and emotion recognition. Applying unbiased hit rates as performance measure, we analyzed data with linear regression analyses, t tests, and with mediation analyses. We found a linear, age-related decrease in emotion recognition independent of stimulus modality and emotional category. In contrast, the improvement in recognition rates associated with audiovisual integration of bimodal stimuli seems to be maintained over the life span. The reduction in emotion recognition ability at an older age could not be sufficiently explained by age-related decreases in hearing, vision, working memory, and verbal intelligence. These findings suggest alterations in social perception at a level of complexity beyond basic perceptional and cognitive abilities.     

Assessing crossmodal matching of abstract auditory and visual stimuli in posterior superior temporal sulcus with MEG

Associating crossmodal auditory and visual stimuli is an important component of perception, with the posterior superior temporal sulcus (pSTS) hypothesized to support this. However, recent evidence has argued that the pSTS serves to associate two stimuli irrespective of modality. To examine the contribution of pSTS to crossmodal recognition, participants (N = 13) learned 12 abstract, non-linguistic pairs of stimuli over 3 weeks. These paired associates comprised four types: auditory–visual (AV), auditory–auditory (AA), visual–auditory (VA), and visual–visual (VV). At week four, participants were scanned using magnetoencephalography (MEG) while performing a correct/incorrect judgment on pairs of items. Using an implementation of synthetic aperture magnetometry that computes real statistics across trials (SAMspm), we directly contrasted crossmodal (AV and VA) with unimodal (AA and VV) pairs from stimulus-onset to 2 s in theta (4–8 Hz), alpha (9–15 Hz), beta (16–30 Hz), and gamma (31–50 Hz) frequencies. We found pSTS showed greater desynchronization in the beta frequency for crossmodal compared with unimodal trials, suggesting greater activity during the crossmodal pairs, which was not influenced by congruency of the paired stimuli. Using a sliding window SAM analysis, we found the timing of this difference began in a window from 250 to 750 ms after stimulus-onset. Further, when we directly contrasted all sub-types of paired associates from stimulus-onset to 2 s, we found that pSTS seemed to respond to dynamic, auditory stimuli, rather than crossmodal stimuli per se. These findings support an early role for pSTS in the processing of dynamic, auditory stimuli, and do not support claims that pSTS is responsible for associating two stimuli irrespective of their modality.     

Seeing to hear better: evidence for early audio-visual interactions in speech identification

Lip reading is the ability to partially understand speech by looking at the speaker's lips. It improves the intelligibility of speech in noise when audio-visual perception is compared with audio-only perception. A recent set of experiments showed that seeing the speaker's lips also enhances sensitivity to acoustic information, decreasing the auditory detection threshold of speech embedded in noise [J. Acoust. Soc. Am. 109 (2001) 2272; J. Acoust. Soc. Am. 108 (2000) 1197]. However, detection is different from comprehension, and it remains to be seen whether improved sensitivity also results in an intelligibility gain in audio-visual speech perception. In this work, we use an original paradigm to show that seeing the speaker's lips enables the listener to hear better and hence to understand better. The audio-visual stimuli used here could not be differentiated by lip reading per se since they contained exactly the same lip gesture matched with different compatible speech sounds. Nevertheless, the noise-masked stimuli were more intelligible in the audio-visual condition than in the audio-only condition due to the contribution of visual information to the extraction of acoustic cues. Replacing the lip gesture by a non-speech visual input with exactly the same time course, providing the same temporal cues for extraction, removed the intelligibility benefit. This early contribution to audio-visual speech identification is discussed in relationships with recent neurophysiological data on audio-visual perception.     

Perceiving emotion from a talker: How face and voice work together

The experiment investigated how the addition of emotion information from the voice affects the identification of facial emotion. We presented whole face, upper face, and lower face displays and examined correct recognition rates and patterns of response confusions for auditory-visual (AV), auditory-only (AO), and visual-only (VO) expressive speech. Emotion recognition accuracy was superior for AV compared to unimodal presentation. The pattern of response confusions differed across the unimodal conditions and across display type. For AV presentation, a response confusion only occurred when such a confusion was present in each modality separately, thus response confusions were reduced compared to unimodal presentations. Emotion space (calculated from the confusion data) differed across display types for the VO presentations but was more similar for the AV ones indicating that the addition of the auditory information acted to harmonize the various VO response patterns. These results are discussed with respect to how bimodal emotion recognition combines auditory and visual information.     

Cross-modal interactions in the experience of musical performances: physiological correlates

This experiment was conducted to investigate cross-modal interactions in the emotional experience of music listeners. Previous research showed that visual information present in a musical performance is rich in expressive content, and moderates the subjective emotional experience of a participant listening and/or observing musical stimuli [Vines, B. W., Krumhansl, C. L., Wanderley, M. M., & Levitin, D. J. (2006). Cross-modal interactions in the perception of musical performance. Cognition, 101, 80--113.]. The goal of this follow-up experiment was to replicate this cross-modal interaction by investigating the objective, physiological aspect of emotional response to music measuring electrodermal activity. The scaled average of electrodermal amplitude for visual-auditory presentation was found to be significantly higher than the sum of the reactions when the music was presented in visual only (VO) and auditory only (AO) conditions, suggesting the presence of an emergent property created by bimodal interaction. Functional data analysis revealed that electrodermal activity generally followed the same contour across modalities of presentation, except during rests (silent parts of the performance) when the visual information took on particular salience. Finally, electrodermal activity and subjective tension judgments were found to be most highly correlated in the audio-visual (AV) condition than in the unimodal conditions. The present study provides converging evidence for the importance of seeing musical performances, and preliminary evidence for the utility of electrodermal activity as an objective measure in studies of continuous music-elicited emotions.     

Audio-visual speech perception is special

In face-to-face conversation speech is perceived by ear and eye. We studied the prerequisites of audio-visual speech perception by using perceptually ambiguous sine wave replicas of natural speech as auditory stimuli. When the subjects were not aware that the auditory stimuli were speech, they showed only negligible integration of auditory and visual stimuli. When the same subjects learned to perceive the same auditory stimuli as speech, they integrated the auditory and visual stimuli in a similar manner as natural speech. These results demonstrate the existence of a multisensory speech-specific mode of perception.     

Atypical crossmodal emotional integration in patients with gliomas

The relevance of emotional perception in interpersonal relationships and social cognition has been well documented. Although brain diseases might impair emotional processing, studies concerning emotional recognition in patients with brain tumours are relatively rare. The aim of this study was to explore emotional recognition in patients with gliomas in three conditions (visual, auditory and crossmodal) and to analyse how tumour-related variables (notably, tumour localisation) and patient-related variables influence emotion recognition. Twenty six patients with gliomas and 26 matched healthy controls were instructed to identify 5 basic emotions and a neutral expression, which were displayed through visual, auditory and crossmodal stimuli. Relative to the controls, recognition was weakly impaired in the patient group under both visual and auditory conditions, but the performances were comparable in the crossmodal condition. Additional analyses using the ‘race model’ suggest differences in multisensory emotional integration abilities across the groups, which were potentially correlated with the executive disorders observed in the patients. These observations support the view of compensatory mechanisms in the case of gliomas that might preserve the quality of life and help maintain the normal social and professional lives often observed in these patients.     

McGurk效应的影响因素与神经基础

McGurk效应(麦格克效应)是典型的视听整合现象, 该效应受到刺激的物理特征、注意分配、个体视听信息依赖程度、视听整合能力、语言文化差异的影响。引发McGurk效应的关键视觉信息主要来自说话者的嘴部区域。产生McGurk效应的认知过程包含早期的视听整合(与颞上皮层有关)以及晚期的视听不一致冲突(与额下皮层有关)。未来研究应关注面孔社会信息对McGurk效应的影响, McGurk效应中单通道信息加工与视听整合的关系, 结合计算模型探讨其认知神经机制等。     

Effects of audio-visual integration on the detection of masked speech and non-speech sounds

Integration of simultaneous auditory and visual information about an event can enhance our ability to detect that event. This is particularly evident in the perception of speech, where the articulatory gestures of the speaker's lips and face can significantly improve the listener's detection and identification of the message, especially when that message is presented in a noisy background. Speech is a particularly important example of multisensory integration because of its behavioural relevance to humans and also because brain regions have been identified that appear to be specifically tuned for auditory speech and lip gestures. Previous research has suggested that speech stimuli may have an advantage over other types of auditory stimuli in terms of audio-visual integration. Here, we used a modified adaptive psychophysical staircase approach to compare the influence of congruent visual stimuli (brief movie clips) on the detection of noise-masked auditory speech and non-speech stimuli. We found that congruent visual stimuli significantly improved detection of an auditory stimulus relative to incongruent visual stimuli. This effect, however, was equally apparent for speech and non-speech stimuli. The findings suggest that speech stimuli are not specifically advantaged by audio-visual integration for detection at threshold when compared with other naturalistic sounds.     

Audio-visual integration of emotional cues in song

We examined whether facial expressions of performers influence the emotional connotations of sung materials, and whether attention is implicated in audio-visual integration of affective cues. In Experiment 1, participants judged the emotional valence of audio-visual presentations of sung intervals. Performances were edited such that auditory and visual information conveyed congruent or incongruent affective connotations. In the single-task condition, participants judged the emotional connotation of sung intervals. In the dual-task condition, participants judged the emotional connotation of intervals while performing a secondary task. Judgements were influenced by melodic cues and facial expressions and the effects were undiminished by the secondary task. Experiment 2 involved identical conditions but participants were instructed to base judgements on auditory information alone. Again, facial expressions influenced judgements and the effect was undiminished by the secondary task. The results suggest that visual aspects of music performance are automatically and preattentively registered and integrated with auditory cues.     

Auditory and visual attention-based apparent motion share functional parallels

A perception of coherent motion can be obtained in an otherwise ambiguous or illusory visual display by directing one's attention to a feature and tracking it. We demonstrate an analogous auditory effect in two separate sets of experiments. The temporal dynamics associated with the attention-dependent auditory motion closely matched those previously reported for attention-based visual motion. Since attention-based motion mechanisms appear to exist in both modalities, we also tested for multimodal (audiovisual) attention-based motion, using stimuli composed of interleaved visual and auditory cues. Although subjects were able to track a trajectory using cues from both modalities, no one spontaneously perceived "multimodal motion" across both visual and auditory cues. Rather, they reported motion perception only within each modality, thereby revealing a spatiotemporal limit on putative cross-modal motion integration. Together, results from these experiments demonstrate the existence of attention-based motion in audition, extending current theories of attention-based mechanisms from visual to auditory systems.     

Matching auditory and visual signals: is sensory modality just another feature?

In order to perceive the world coherently, we need to integrate features of objects and events that are presented to our senses. Here we investigated the temporal limit of integration in unimodal visual and auditory as well as crossmodal auditory-visual conditions. Participants were presented with alternating visual and auditory stimuli and were asked to match them either within or between modalities. At alternation rates of about 4 Hz and higher, participants were no longer able to match visual and auditory stimuli across modalities correctly, while matching within either modality showed higher temporal limits. Manipulating different temporal stimulus characteristics (stimulus offsets and/or auditory-visual SOAs) did not change performance. Interestingly, the difference in temporal limits between crossmodal and unimodal conditions appears strikingly similar to temporal limit differences between unimodal conditions when additional features have to be integrated. We suggest that adding a modality across which sensory input is integrated has the same effect as adding an extra feature to be integrated within a single modality.     

Audio-visual simultaneity judgments

The relative spatiotemporal correspondence between sensory events affects multisensory integration across a variety of species; integration is maximal when stimuli in different sensory modalities are presented from approximately the same position at about the same time. In the present study, we investigated the influence of spatial and temporal factors on audio-visual simultaneity perception in humans. Participants made unspeeded simultaneous versus successive discrimination responses to pairs of auditory and visual stimuli presented at varying stimulus onset asynchronies from either the same or different spatial positions using either the method of constant stimuli (Experiments 1 and 2) or psychophysical staircases (Experiment 3). The participants in all three experiments were more likely to report the stimuli as being simultaneous when they originated from the same spatial position than when they came from different positions, demonstrating that the apparent perception of multisensory simultaneity is dependent on the relative spatial position from which stimuli are presented.