Investigation of effects of face rotation on race processing: An ERPs study

Recent ERP research has indicated that the processing of faces of other races (OR) and same race (SR) as the perceiver differs at the perceptual level, more precisely for the N170 component. The purpose of the present study was to continue the investigation of the race-of-face processing across multiple orientations. Event-related brain potentials (ERPs) and performance were recorded when Caucasian participants were required to categorize by race Caucasian and African faces presented in eight different angles of orientation. Three main observations were made: (1) the face-sensitive N170 is modulated by the race of faces, being larger in response to OR compared to SR faces; (2) face rotation affected this component in the same pattern for both racial groups; (3) the N170-ORE progressively disappeared as the faces moved away from their canonical orientation at the right hemisphere only. Thus, the current findings suggest that configural/holisitic information is extracted from faces of both racial groups, but that upright OR faces require increased demands.     

ERP evidence for task modulations on face perceptual processing at different spatial scales

Does the perceptual processing of faces flexibly adapt to the requirements of the categorization task at hand, or does it operate independently of this cognitive context? Behavioral studies have shown that the fine and coarse spatial scales of a face are differentially processed depending on the categorization task performed, thus suggesting that the latter can influence stimulus perception. Here, we investigated the time course of these task influences on perceptual processing by examining the visual N170 face‐sensitive Event‐Related Potential (ERP), while observers categorized faces for their gender and familiarity. Stimuli were full spectrum, or filtered versions that preserved either coarse or fine scale information of the faces. Behavioral results replicated previous findings of a differential processing of coarse and fine spatial scales across tasks. In addition, the N170 amplitude was larger in the Gender task as compared to the Familiarity task for LSF faces exclusively, thus showing that task demands differentially modulated the spatial scale processing on faces. These results suggest that the diagnosticity of scale‐specific cues in categorization tasks can modulate face processing.     

The influence of processing objectives on the perception of faces: An ERP study of race and gender perception

In two experiments, event-related potentials were used to examine the effects of attentional focus on the processing of race and gender cues from faces. When faces were still the focal stimuli, the processing of the faces at a level deeper than the social category by requiring a personality judgment resulted in early attention to race and gender, with race effects as early as 120 msec. This time course corresponds closely to those in past studies in which participants explicitly attended to target race and gender (Ito &Urland, 2003). However, a similar processing goal, coupled with a more complex stimulus array, delayed social category effects until 190 msec, in accord with the effects of complexity on visual attention. In addition, the N170 typically linked with structural face encoding was modulated by target race, but not by gender, when faces were perceived in a homogenous context consisting only of faces. This suggests that when basic-level distinctions between faces and nonfaces are irrelevant, the mechanism previously associated only with structural encoding can also be sensitive to features used to differentiate among faces.     

The association of physical activity to occipito-temporal processing during face recognition

ObjectivesThis study examined the association between physical activity level and primitive cognitive processing during a face recognition task in young adults, a topic that has received little attention.DesignCross-sectional.MethodsThe face recognition task required participants to respond to famous faces but not respond to unfamiliar faces. Task performance and several occipito-temporal event-related brain potentials reflecting the various stages of face processing, from perceptual encoding (N170) to recognition (N250 and face-N400), were assessed during the face recognition task.ResultsAlthough analyses revealed no significant group differences in behavioral performance measures, neuroelectric data showed different time courses of face recognition processes between groups. Active individuals exhibited larger N250 amplitude, reflecting an early stage of facial recognition, for famous relative to unfamiliar faces, whereas inactive individuals did not exhibit such a difference.ConclusionsThese findings are suggestive of a possible association between physical activity and relatively early, primitive cognitive processes.     

知觉负载对负性分心面孔的知觉加工和记忆的影响

本研究采用视觉搜索和意外再认记忆任务,结合事件相关电位技术,考察知觉负载对负性分心面孔的知觉加工和记忆的影响。在视觉搜索任务中,行为上恐惧分心面孔在高负载下干扰任务。ERP结果上,恐惧比中性分心面孔诱发更大的N170和N250;在低负载下恐惧比中性分心面孔诱发更大的N700,在高负载下没有差异。在意外再认记忆中,个体对低负载下的恐惧分心面孔表现出记忆。这些结果说明负性分心物在早期是自动化加工;晚期加工受知觉负载的调节,负载越低对负性分心物的过滤越少,存在对负性分心物的记忆偏向。     

Symmetrical interaction of sex and expression in face classification tasks

Classification of faces as to their sex or their expression—with sex and expression varying orthogonally—was studied in three experiments. In Experiment 1, expression classification was influenced by sex, with angry male faces being classified faster than angry female faces. Complementarily, sex classification was faster for happy than for angry female faces. In Experiment 2, mutual interaction of sex and expression was also found when the participants were asked to classify top and bottom face segments. In Experiment 3, a face inversion effect was found for both sex and expression classification of whole faces. However, a symmetrical interaction between sex and expression was again found. The results are discussed in terms of configural versus feature processing in the perception of face sex and expression and of their relevance to face perception models that postulate independent processing of different facial features. 2009 The Psychonomic Society, Inc.     

Electrophysiological correlates of the composite face illusion: Disentangling perceptual and decisional components of holistic face processing in the human brain

When the bottom halves of two faces differ, people’s behavioral judgment of the identical top halves of those faces is impaired: they report that the top halves are different, and/or take more time than usual to provide a response. This behavioral measure is known as the composite face effect (CFE) and has traditionally been taken as evidence that faces are perceived holistically. Recently, however, it has been claimed that this effect is driven almost entirely by decisional, rather than perceptual, factors ( Richler, Gauthier, Wenger, & Palmeri, 2008). To disentangle the contribution of perceptual and decisional brain processes, we aimed to obtain an event-related potential (ERP) measure of the CFE at a stage of face encoding ( Jacques & Rossion, 2009) in the absence of a behavioral CFE effect. Sixteen participants performed a go/no-go task in an oddball paradigm, lifting a finger of their right or left hand when the top half of a face changed identity. This change of identity of the top of the face was associated with an increased ERP signal on occipito-temporal electrode sites at the N170 face-sensitive component (∼160 ms), the later decisional P3b component, and the lateralized readiness potential (LRP) starting at ∼350 ms. The N170 effect was observed equally early when only the unattended bottom part of the face changed, indicating that an identity change was perceived across the whole face in this condition. Importantly, there was no behavioral response bias for the bottom change trials, and no evidence of decisional biases from electrophysiological data (no P3b and LRP deflection in no-go trials). These data show that an early CFE can be measured in ERPs in the absence of any decisional response bias, indicating that the CFE reflects primarily the visual perception of the whole face.     

The role of eyes in early face processing: a rapid adaptation study of the inversion effect

The current study employed a rapid adaptation procedure to test the neuronal mechanisms of the face inversion effect (FIE) on the early face-sensitive event-related potential (ERP) component N170. Five categories of face-related stimuli (isolated eyes, isolated mouths, eyeless faces, mouthless faces, and full faces) and houses were presented in upright and inverted orientations as adaptors for inverted full face test stimuli. Strong adaptation was found for all face-related stimuli except mouths. The adaptation effect was larger for inverted than upright stimuli, but only when eyes were present. These results underline an important role of eyes in early face processing. A mechanism of eye-dependent orientation sensitivity during the structural encoding stage of faces is proposed.     

Race-based perceptual asymmetries underlying face processing in infancy

Adults process other-race faces differently than own-race faces. For instance, a single other-race face in an array of own-race faces attracts Caucasians’ attention, but a single own-race face among other-race faces does not. This perceptual asymmetry has been explained by the presence of an other-race feature in other-race faces and its absence in own-race faces; this difference is thought to underlie race-based differences in face processing. We examined the developmental origins of this mechanism in two groups of Caucasian 9-month-olds. Infants in the experimental group exhibited a preference for a pattern containing a single Asian face among seven Caucasian faces over a pattern containing a single Caucasian face among seven Asian faces. This preference was not driven by the majority of elements in the images, because a control group of infants failed to exhibit a preference between homogeneous patterns containing eight Caucasian versus eight Asian faces. The results demonstrate that an other-race face among own-race faces attracts infants’ attention but not vice versa. This perceptual asymmetry suggests that the other-race feature is available to Caucasians by 9 months of age, thereby indicating that mechanisms of specialization in face processing originate early in life.     

Deficits in early-stage face perception in excessive internet users

Excessive Internet use is associated with a limited ability to communicate effectively socially, which depends largely on the capacity for perception of the human face. We used a passive visual detection paradigm to compare the early stages of the processing of face-related information in young excessive Internet users (EIUs) and healthy normal subjects by analyzing event-related potentials (ERPs) elicited by faces and by nonface stimuli (tables), each presented in the upright and inverted position. The P1 and N170 components of the spectrum of ERPs elicited at occipital-temporal sites by the viewing of faces were larger and peaked sooner than the same ERP components elicited by tables, and inverted faces significantly enhanced and delayed the N170 component. EIUs had a generally smaller P1 component than did normal subjects, whether elicited by faces or by tables, and the N170 effect, or difference in amplitude of the N170 component for faces versus tables, was significantly smaller in the EIUs than in normal subjects. However, the N170 inversion effect, or difference in amplitude of the N170 component elicited by upright versus inverted faces, was similar in the EIUs and normal subjects. These data indicate that EIUs have deficits in the early stage of face-perception processing but may have intact holistic/configural processing of faces. Whether some deeper processes of face perception, such as face memory and face identification, are affected in EIUs needs to be investigated further with more specific procedures.     

知觉场理论对面孔知觉年龄偏差效应的解释

使用融合面孔范式和倒置面孔范式来研究面孔知觉的年龄偏差效应,检验知觉场能否作为面孔整体加工的指标,并以此发展年龄偏差的整体加工解释。结果发现：（1）成人和儿童在加工正立面孔时的知觉场均大于加工倒置面孔时的知觉场;（2）在加工正立面孔时,成人加工本年龄面孔比加工他年龄面孔的知觉场更大。上述结果表明：（1）知觉场大小可以作为面孔整体加工的指标,且受面孔朝向的影响;（2）知觉场假设可以解释面孔的年龄偏差效应。     

知觉场理论对面孔知觉年龄偏差效应的解释

使用融合面孔范式和倒置面孔范式来研究面孔知觉的年龄偏差效应,检验知觉场能否作为面孔整体加工的指标,并以此发展年龄偏差的整体加工解释。结果发现：（1）成人和儿童在加工正立面孔时的知觉场均大于加工倒置面孔时的知觉场;（2）在加工正立面孔时,成人加工本年龄面孔比加工他年龄面孔的知觉场更大。上述结果表明：（1）知觉场大小可以作为面孔整体加工的指标,且受面孔朝向的影响;（2）知觉场假设可以解释面孔的年龄偏差效应。     

Behavioral and ERP measures of holistic face processing in a composite task

Holistic processing of faces is characterized by encoding of the face as a single stimulus. This study employed a composite face task to examine whether holistic processing varies when attention is restricted to the top as compared to the bottom half of the face, and whether evidence of holistic processing would be observed in event-related potentials. Analyses of behavioral data showed that spatial misalignment of the face halves disrupted holistic processing and enhanced detection of repeated attended halves. Effects of misalignment on the N170, VPP and N250 ERP components resembled effects of face inversion. Attention to the top half of the face was associated with faster P1, N170, VPP, and P2 latencies than attending to the bottom, suggesting automatic processing of the eye region. Further, N170 latency effects suggested that structural encoding of the face is facilitated during holistic processing. N250 latency effects reflected task difficulty. Finally, an overall right hemispheric asymmetry was most pronounced when holistic face processing was greatest. Results are discussed in light of recent proposals that holistic face processing is a subtype of configural face processing.     

面孔识别特异性本质的ERP研究

本研究记录了16名被试在完成有整体结构变化和局部特征变化的面孔/房屋图片的一致性判断时的脑内时程变化,以期对面孔识别的特异性本质进行探讨。结果显示,N170波幅和潜伏期的刺激类型主效应显著;面孔/房屋所诱发的N170成分在波幅和潜伏期上均不存在加工方式上的显著差异。晚期成分(300～700ms)上也得到类似的结果。这表明:面孔与房屋(非面孔)的加工在早期和晚期成分上都有差异性,体现出面孔的加工在早期视觉刺激的加工和晚期识别的加工上都具有特异性;晚期识别加工的脑电结果不支持"面孔识别是整体的,结构的,而非面孔客体的识别是局部的,基于特征的"加工观点。     

Glucose regulation and face recognition deficits in older adults: the role of attention

The present study investigated the perceptual, attentional, and memory processes underlying face recognition deficits observed in older adults with impaired glucoregulation. Participants were categorized as good glucoregulators or poor glucoregulators on the basis of an oral glucose tolerance test. Using event-related potential (ERP) methodology, 23 participants (62–88 years) performed a 2-stimulus oddball task. Participants were asked to rate and memorize 10 “target” faces, which were then presented amongst 120 unfamiliar foils. Behavioral results indicated that good glucoregulators were significantly more accurate at recognizing target faces. ERP markers of early visual perception (P1 and N170 components) and memory formation (P3 component) were unaffected by glucoregulatory efficiency. The P2 component, an index of attentional processing, was larger and delayed in the poor glucoregulators. To the best of our knowledge, this study is the first to suggest that face recognition deficits in poor glucoregulators may be due to impairments in attentional processing.     

Reducing the own-race bias in face recognition by shifting attention

The own-race bias (ORB) in face recognition can be interpreted as a failure to generalize expert perceptual encoding developed for own-race faces to other-race faces. Further, black participants appear to use different features to describe faces from those used by white participants (Shepherd & Deregowski, 1981). An experiment is reported where the size of the ORB was assessed using a standard face recognition procedure. Four groups were tested at two time intervals. One group received a training regime involving learning to distinguish faces that varied only on their chin, cheeks, nose, and mouth. Three control groups did not receive this training. The ORB, present prior to training, was reduced after the critical perceptual training. It is concluded that the ORB is a consequence of a failure of attention being directed to those features of other race faces that are useful for identification.     

Age-related changes in amplitude,latency and specialization of ERP responses to faces and watches

ABSTRACT

Healthy aging is associated with impairments in face recognition. While earlier research suggests that these impairments arise during memory retrieval, more recent findings suggest that earlier mechanisms, at the perceptual stage, may also be at play. However, results are often inconsistent and very few studies have included a non-face control stimulus to facilitate interpretation of results with respect to the implication of specialized face mechanisms vs. general cognitive factors. To address these issues, P100, N170 and P200 event-related potentials (ERPs) were measured during processing of faces and watches. For faces, age-related differences were found for P100, N170 and P200 ERPs. For watches, age-related differences were found for N170 and P200 ERPs. Older adults showed less selective and less lateralized N170 responses to faces, suggesting that ERPs can detect age-related de-differentiation of specialized face networks. We conclude that age-related impairments in face recognition arise in part from difficulties in the earliest perceptual stages of visual information processing. A working model is presented based on coarse-to-fine analysis of visually similar exemplars.     

Knowledge scale effects in face recognition: An electrophysiological investigation

Although the amount or scale of biographical knowledge held in store about a person may differ widely, little is known about whether and how these differences may affect the retrieval processes triggered by the person’s face. In a learning paradigm, we manipulated the scale of biographical knowledge while controlling for a common set of minimal knowledge and perceptual experience with the faces. A few days after learning, and again after 6 months, knowledge effects were assessed in three tasks, none of which concerned the additional knowledge. Whereas the performance effects of additional knowledge were small, event-related brain potentials recorded during testing showed amplitude modulations in the time range of the N400 component—indicative of knowledge access—but also at a much earlier latency in the P100 component—reflecting early stages of visual analysis. However, no effects were found in the N170 component, which is taken to reflect structural analyses of faces. The present findings replicate knowledge scale effects in object recognition and suggest that enhanced knowledge affects both early visual processes and the later processes associated with semantic processing, even when this knowledge is not task-relevant.     

Event-related brain potentials reveal differences in emotional processing in alexithymia

ABSTRACT

The inability to recognise and describe emotions in the self is known as Alexithymia. In the present study we used event-related potentials (ERPs) to examine the locus of processing emotional differences in alexithymia. We tested men, both those scoring high (score?>?61) and controls who scored low (score?<?51) on the Toronto Alexithymia Scale-20 on an emotional face discrimination task. We assessed three ERP components: P1 (an index of early perceptual processing), N170 (an index of early facial processing) and P3 (an index of late attentional suppression). While controls showed a stronger P3 effect for angry faces relative to happy and neutral faces, Alexithymic men showed no significant differences in P3 across emotions. Alexithymic men showed delayed P1 and N170 amplitudes compared to controls. These results suggest that the locus of processing differences between alexithymic men and controls occur both early in perceptual processing and later in conscious processing.     

The neurophysiological correlates of face processing in adults and children with Asperger's syndrome

Past research has found evidence for face and emotional expression processing differences between individuals with Asperger's syndrome (AS) and neurotypical (NT) controls at both the neurological and behavioural levels. The aim of the present study was to examine the neurophysiological basis of emotional expression processing in children and adults with AS relative to age- and gender-matched NT controls. High-density event-related potentials were recorded during explicit processing of happy, sad, angry, scared, and neutral faces. Adults with AS were found to exhibit delayed P1 and N170 latencies and smaller N170 amplitudes in comparison to control subjects for all expressions. This may reflect impaired holistic and configural processing of faces in AS adults. However, these differences were not observed between AS and control children. This may result from incomplete development of the neuronal generators of these ERP components and/or early intervention.