The Effect Of Facial Expression And Familiarity On The Attentional Blink

The attentional blink(AB) refers to the finding that people have difficulties in identifying the second of two masked targets (T1and T2) within a rapid serial visual presentation (RSVP) stream of distractors if T2 is presented within approximately 500 milli-second after T1. Humans are endowed with capabilities enhancing the quick and efficient detection of stimuli significant to the organism. however, These capabilities appear to reach their limits when two such tagets occur in rapid succession. The AB has become central in the study of attention in the past two decades. Especially,in recent years the underlying cause of the AB has emerged as a topic of intense debate. This AB effect is very robust and can be obtained under a wide variety of task conditions and in the great majority of subjects. The AB has been demonstrated with a wide range of stimuli, including letters, numbers, words, symbols, geometric shapes, pictures, colors and with auditory or tactile stimuli.The AB has proven to be a useful tool in the study of interaction between working memory and attention. Questions that exploration of the AB seems well suited to answer are how a stimulus can break into the area of conscious awareness. Fundamental knowledge obtained from the AB has even been used to study information processing in practical applications such as psychological assessment, inter face design and warning signals. Finally, it has had a large impact in developmental and clinical settings, helping to elucidate cognitive limitations in elderly and people suffering from visual neglect, schizophrenia, depression, ADHD, and dyslexia.The attentional blink has been studied by means of two paradigms:rapid serial visual presentation (RSVP), in which targets are embedded in a stream of central distractors, and the two-target paradigm, in which targets are presented eccentrically without distractors.Most studies of visual attention have addressed the question of how multiple stimuli are processed when they are presented simultaneously in a single spatial array. Therefore, we use a rapid serial visual presentation paradigm to investigate the characteristics of attention form time dimension. In present study, we used RSVP paradigm, on each trial, participants were presented a sequence of 15 Stimuli,2 target face(T1 and T2) and 13 distractor Stimuli, at the center of a black screen. Each probe was presented for 100 milli-second with no break between the faces. We presented 1,2, 3,4, or5 distractor Stimuli between T1 and T2, corresponding to five temporal lags ranging from a stimulus onset asynchrony (SOA) of 200 ms to a SOA of 600 ms.This study explored AB effect in face recognition. It included a series of nine experiments for two parts.Expression and familiarity are recognized as two important factors in the processing of the faces recognition. The attentional blink effect maybe under the influence of the T1 expression, but also can be affected by the T2 expression. The study 1 used high and low cognitive load, setted expression judge task and gender judge task, and used the same or different processing channel, examined the influence mechanism of the face expression to the attentional blink effect systematically. What's more, used the ERP as indicators, examined the time processing and cognitive mechanism of it. The study 2 used repeated target or unrepeated target condition, by changing the nature of the familiar of T2, and the potential semantic relation between T1 and T2, System to examined the influence mechanism of the familiarity to the attentional blink effect systematically, and also used the ERP, examined the time processing and cognitive mechanism of it.The study 1:the influence of the face expression on the attentional blink effectIn the experiment 1, using a rapid serial visual presentation paradigm, we investigated whether an emotional T2 reduces the AB when preceded by a neutral Tl. Our results indicate that emotional T2 have strong effect on the AB and that aversive T2 attenuated the AB in the presence of a neutral.In the experiment 2, using a rapid serial visual presentation paradigm, we investigated whether an emotional T1 reduces the AB when offside by an neutral T2. In Experiment 3-a, participants had to judge T1's gender; hence, the face pictures were task relevant, but attention was not explicitly directed to their emotional expression. In Experiment 3-b, participants had to explicitly judge the facial expression of T1 stimuli; thus, the face pictures were task relevant, and attention was directed to their emotional expression. Our results indicate that an emotional T1 has strong effect on the AB:First, angry faces induced a stronger AB than neutral faces when faces were task relevant and attention was directed to the facial expression. Second, with identical physical stimulation, the enhancement of the AB by angry faces disappeared when participants' attention was directed to a nonemotional facial feature.In the experiment 3, using a rapid serial visual presentation paradigm, we investigated the effect of angry, happy and neutral face stimuli on the report of trailing scene targets. When the emotional expression of the face stimuli had to be indicated, fearful faces induced a stronger attentional blink than neutral faces. Under different processing conditions, the different cognitive structure of T1 and T2 make more rational distribution for limited resources.In the experiment 4, setted low cognitive load condition and high cognitive load condition, we investigated whether AB depends on currently available attentional resources. Our results indicate that observers detected faces presented during the attentional blink period that could depict either an angry or a happy expression. Perceptual load of the blink-inducing target was manipulated by a happy expression and a neutral expression. The privileged access of fearful faces to awareness does not occur mandatorily, but instead of depending on attentional resources.In the experiment 5, using ERP and a rapid serial visual presentation paradigm, we investigated the neural mechanism of an emotional T2 reducing the AB when preceded by a neutral T1.ERP components are modulated by facial express valence in the early phase of perception and cognitive evaluation. Early anterior N1and posterior P2 reflect the bias for processing the angry expression, the angry expression elicited larger amplitude than happy and neutral expressions. The amplitude of N170 in short interval condition can distinguish the emotional facial from neutral face stimuli. The amplitude P3 can distinguish among emotional facial expression such as angry expression, happy expression, and neutral faces.The study 2:the influence of the face familiarity on the attentional blink effectIn the experiment 6, in order to investigate the contribution of perceptual structure and semantic representation on face repetition priming, we explored priming effects of recognizing familiar and unfamiliar faces and how this priming is influenced by face inversion. The results are as follows:(1) Familiar faces show priming of perceptual structure and semantic representation, whereas unfamiliar ones only show priming of the perceptual structure; (2) The contribution of perceptual structure and semantic representation is not dissociated but combined, and the semantic priming effect is larger than the perceptual priming in familiar faces; (3) The contribution of perceptual structure and semantic representation is related to process stages. Perceptual structure and semantic representation evokes larger repetition effects during early stage of processing, and semantic representation evokes greater repetition effects during the later stages of processing.In the experiment 7, using a rapid serial visual presentation paradigm, in order to investigate the contribution of potential semantic representation between T1and T2 to the AB, we explored priming effects of recognizing star spouse and nonstar spouse faces. The results indicates that under Lag2 condition, the AB of the T2 stimuli of semantic relationship with the T1 have disappeared, which suggests that potential semantic representation between Tland T2 can break through the bottleneck of attention.In the experiment 8, we investigated the effect of face familiarity to the AB when the T1 is stranger face and the T2 is star face. The behavior results indicate that the AB of the T2 stimuli has reduced. And the ERP data shows that ERP components are not modulated by facial familiarity valence in the early phase of perception and cognitive evaluation. However, the amplitude P3 can distinguish familiar face form unfamiliar face.The thesis can make the following conclusions based on the above nine experiments:1.The AB effect is influenced by both the T1 expression and the T2 expression and processing of threat stimuli can be enhanced under conditions of limited attentional resources.2. Face expression exerts effect on the AB through different processing passageways. Under the same passageway, the occupying of central processing is likely to initiate the psychological refractory period. However, under different processing conditions, the different cognitive structure of T1 and T2 make more rational distribution for limited resources.3. From the occurring of the AB effect, ERP components are modulated by facial express valence in the early phase of perception and the later phase of perception. Under the limited cognitive resources, fearful faces can be separated from other emotional faces in the early phase of perception.4. Semantic representation of faces can motivate the priming effect in the very short time intervals and potential semantic representation between T1and T2 can break through the bottleneck of attention.5. The face familiarity has proven to be a useful tool in breaking through the bottleneck of attention. In the other hand, ERP components are not modulated by facial familiarity valence in the early phase of perception and cognitive evaluation. However, the amplitude P3, the indicator of the later phase of perception, can distinguish familiar face from unfamiliar face.