Music and language are arguably the most characteristic traits of human beings. On one hand, previous functional magnetic resonance imaging (fMRI) studies have identified multiple cortical regions that are involved in the processing of both music and language, suggesting shared neural substrate for music and language. On the other hand, neuropsychological studies on brain-lesioned patients show the double dissociation between music and language, suggesting distinct neural substrates for music and language respectively. Here we used meta-analysis to examine the relation of the neural basis underlying music and language. First, we adopted the data from three meta-analysis studies on music and language respectively. Specifically, for the neural substrate of music, we focused on two processing levels specific to music processing, which were interval analysis (15 contrasts and 63 peaks) and structure analysis (19 contrasts and 217 peaks) (Lai, Xu, Song, & Liu, 2013). For the neural substrate of language, three processing levels specific to language processing were selected, which were phonological analysis (86 contrasts and 344 peaks), lexico-semantic analysis (111contrasts and 339 peaks), and sentence analysis (65 contrasts and 218 peaks) (Vigneau et al., 2006; Vigneau et al., 2011). Second, we projected these peak activation elicited by processing either music or language onto the MNI (Montreal Neurological Institute) space to visualize the distribution of cortical regions involved in music and language with Caret. Finally, to explore the relation of neural substrates underlying music and language, we calculated whether pairs of peak activation were spatially overlapped or dissociated by K-means clustering and multivariate analysis of variance (MANOVA). The overlapping rate was estimated to quantify the extent to which music and language shared common neural substrates. We finally found 11 pairs of overlapping clusters. Music and language shared neural substrates at all levels of processing tested. Specially, the overlapped clusters from phonological processing of language and music perception were mainly in the auditory-motor loop, the overlapped clusters from semantic processing and music perception were in core loop, and the overlapped clusters of sentence processing and music were in cognition-emotion loop. In addition, the neural substrate underlying interval analysis of music overlapped with that underlying language processing as much as 50% in left hemisphere, which was mainly in the left superior temporal gyrus, left precentral gyrus, left pars triangularis of the inferior frontal gyrus and right insular. The neural substrate underlying structure analysis of music overlapped with that underlying language processing as much as 7% and 14% in the left and right hemisphere respectively, which was mainly in left Rolandic operculum, right pars opercularis of the inferior frontal gyrus and right insular. In sum, our study illuminates the functionality of the distinct and shared neural substrates underlying music and language. That is, for lower-level processes, such as interval analysis, phonological analysis and lexico-semantic analysis, music and language are more likely to share the same neural substrate in auditory analysis, auditory-motor integration and working memory. By contrast, for higher-level processes, especially in the structure analysis and sentence analysis, the neural substrate underlying music is more likely distinct from that underlying language. Models were proposed to illustrate the distinct and shared neural mechanisms underlying music and language, which invites future studies on the relation between music and language.
To recognize or report the second occurrence of a target in RSVP paradigm is challenging, a phenomenon known as Repetition Blindness (RB; Kanwisher, 1987). Some scholars argue that RB is due to an encoding failure of a repeated stimulus (e.g., Kanwisher, 1987, 1991; Kanwisher & Potter, 1989, 1990), while others believe it is caused by a retrieval failure (e.g., Armstrong & Mewhort, 1995; Fagot & Pashler, 1995; Masson, 2004; Whittlesea & Masson, 2005). Morris, Still and Caldwell-Harris (2009) proposed the Competition Hypothesis to further explain RB with inter-item competition. However, under the time press, people may allocate attention resources according to the task to get the best recall performance. In the RSVP paradigm, to serve the purpose of detecting more distinctive stimuli, repeated stimuli receive less attention resource than the non-repeated stimuli during the perceptual phase. Consequently, repeated items become difficult to report during the retrieval phase. Recently, Leng, Tan, Zeng, Cheng, and Lu (2012) illustrated these views in their Optimization Allocation of Attention Resources Hypothesis. The present study aimed to further examine the mechanism of RB through a new method. The typical RSVP paradigm includes one pair of repeated item (single repetition, C1 and C1’).In our research, two pairs of repeated items (double repetition, C1 and C1’, and C2 and C2’) were created. A within-subject design with one variable was used in all three experiments, repetition of words with three levels (non-repeated, one pair of word repeated, and two pairs of words repeated). The dependent variable was the accuracy rate for reporting targets. If RB occurs in a single repetition RSVP and it occurs at the perceptual phase, then the effect of RB from the second repeated stimulus (C2’) should not occur in a double repetition RSVP because the first repeated stimulus (C2) can not be recognized in the RSVP streams. If RB occurs at the retrieval phase in a single repetition RSVP, then the effect of RB from the second repeated stimulus should occur in a double repetition RSVP because the first repeated stimulus can be recognized in the RSVP displays. The second pairs repeated stimuli C2 and C2’ as well as an item between them construct a single repetition RSVP, in which the RB from C2’ should occur. In Experiment 1, both targets and non-targets were neutral words; while in Experiments 2a and 2b, targets were emotional words and non-targets were neutral words. Experiment 1 found that the accuracy rate for targets in the singly repeated but not in the doubly repeated condition differed from accuracy rate in the non-repeated condition. However, in Experiments 2a and 2b, the accuracy rate for targets in the doubly repeated condition but not in the singly repeated condition differed from the accuracy rate in the non-repeated condition. The results indicated: (1) The methodological merits of the repetitiveness of doubly repeated stimuli in a RSVP paradigm depended on the value intensity of targets and non-targets. When the intensity between them was equivalent, the second repeated targets showed advantage. When the intensity from the targets was stronger relative to the non-targets, the second repeated targets showed disadvantage. (2) People can allocate more attention resources to the stimui with higher intensity. RB occurs at the retrieval phase, not at the perception phase. The Optimization Allocation of Attention Resources Hypothesis can reasonably explain the effect of RB.
It has been well documented that that personal significance modulates the high-level cognitive processes, including face recognition, memory and thinking. How personal significance (i.e., the self) modulates the visual selection remains poorly understood, however. Here by combining recent developed self-associative learning approach and a global-local task, this article present the evidence that self-salience impacted on visual selection–eliminating the effect of global advantage. The pattern consistently occurred in both divided and focused attention tasks. In contrast, this was not the case for friend-associations. The present study report 3 experiments to test how the self-salience modulated the selection of attention. It first developed a baseline experiment showing a global advantage effect in Experiment 1; 24 participants participated in Experiment 1 and carried out two tasks – a self-associative learning task following by a global-local task. In the self-associative learning task, three geometric shapes were randomly assigned to three persons (self, friend, and a stranger). Having formed a personal association, participants performed the global-local task where they were presented compound shapes (e.g. a global circle formed by local squares, self – square, stranger – circle, local self forming global stranger) and had to identify the shape-associated person (self vs. friend). Targets randomly appeared at either the global or local level. Reaction time and accuracy performance were measured and analyzed using repeated-measures analyses of variance (ANOVAs) with Social Relevance (self vs. friend) and Attention Level (global vs. local). Experiment 2 was identical to Experiment 1 except that the stranger-related shapes were targets while the self- and friend-related shapes had to be ignored. There were 20 participants in Experiment 2. Different from Experiments 1 and 2 where the divided attention task was employed, Experiment 3 used a focus attention task where participants were instructed to complete either a local or global task in different blocks. There were three within-subjects factors with 2 (Social Relevance: self vs. friend) × 2 (Saliency Level: global saliency vs. local saliency) × 2 (Attention Level: global vs. local). 24 participants participated in Experiment 3. The results in Experiment 1 showed a reliable self-advantage effect where faster responses to global than local level targets occurred in both the self- and friend-related target conditions. In contrast, the global advantage to targets (stranger-shapes) was eliminated in the presence of self-related distractors while the effect survived in the presence of friend-related distractors in Experiment 2. The interference effect of self-salience was verified in Experiment 3where the focused rather than divided attention task (in Experiment 2) was used. In conclusion, the results demonstrated that compared with friend-related information, the self as distractors affected the global advantage effect, and the effect appeared at both global and local levels unanimously and cannot be influenced by task. The data indicate that self-saliency can modulate basic visual selection.
The current study investigated the age differences in repetition priming of studied or new objects in a delayed-matching-to-sample task involving common objects. Prior to matching task, older or young participants intentionally studied a set of object pictures. For the matching task, a trial began with the presentation of two sample pictures (both were studied objects or both were new objects), then followed by twelve successive test pictures. The test pictures were classified into four types: studied match, new match, studied non-match, new non-match. Each types of test picture were repeated for three to four times within each trial. Participants were instructed to judge whether each test picture match one of the sample pictures or not as quickly and as accurately as possible. The results showed that older adults were generally slower than young adults in response, and both older and young participants respond faster to matches than to non-matches. RTs to studied matches were faster than to new matches, but RTs to studied non-matches were slower than to new non-matches for both older and young adults. Moreover, both older and young adults showed repetition effect for matches, with reduced repetition effect for non-matches. Repetition effect was reduced over times, and was differentiated between older and young participants. Importantly, while young adults showed no repetition effect for studied non-matches, older adults were significantly longer in response to repeatedly presented studied non-matches. These results demonstrated that implicit repetition effects for objects in older and young adults were affected by previous experiences with these objects. Repeatedly presented non-matches induced higher familiarity and caused difficulty for older adults in rejecting them, but this familiarity did not affect young adults.
Researchers have highlighted the relations among language, culture and thinking for a long time and there have been two viewpoints including Universalism and Relativism concerning this topic. Universalism assumes that we comprehend, produce and learn language using the same cognitive mechanisms. Relativism by Sapir-Whorf hypothesis assumes that language affect cognition. Researchers have found a large body of evidences supporting Sapir-Whorf hypothesis such as color categorization, spatial reasoning, temporal comparisons, and grammatical gender. Language is an important factor that may influence how we reason about the world, or even how we perceive it. The differences of English and Chinese mainly reflect in word order when scene is expressed. Do structural differences of language lead to differentiation of scenery cognition? What is the mechanism if languages can lead subjects to process scenes differently? To investigate the above problems may help to furthering the research on the relationships of language, culture and thinking, as well as providing evidence for the impact of language on cognition. Eye movement experiment was used to investigate the impact of primed language on Chinese-English bilinguals’ scene processing. A total of 20 college students (7 males and 13 females) were participated in this study. 2 (language style) × 3 (picture-text consistency relations) design was used. Language style contained Chinese and English, picture-text consistency relations contained three types including consistency condition, foreground object inconsistency condition and background information inconsistency condition. The materials included 48 pictures and 96 primed phrases (48 Chinese phrases and 48 English phrases respectively). Among the 48 pairs of picture-text materials, there were 16 pairs sharing the same meaning between the contents of pictures and the meaning of primed phrases; the meaning of 16 primed phrases were different from the contents of pictures which was mainly reflected in the foregrounds; the meaning of 16 primed phrases were different from the contents of pictures which was mainly reflected in the backgrounds. At the beginning of the experiment, primed phrases of English or Chinese were presented, and then subjects were asked to judge the consistency relations of pictures-text pairs under Chinese and English primed conditions. The results showed that primed phrases influenced bilinguals’ scene processing. Significant differences occurred on several eye movement index under the English and Chinese conditions such as the fixation duration, the fixation duration in objects, the fixation duration in backgrounds, the number of fixations in backgrounds, and the average fixation duration. The proportion of fixations to object across 14 fixations under English and Chinese primed language were depicted, which showed that in English priming condition, the backgrounds obtained extra and fast attention due to the postposition of backgrounds’ information in word order. Under the Chinese condition, the transfer from foregrounds to backgrounds was late and the watching proportion was few. These differences were related to not only the properties of languages but also the depth of processing. Features of eye movement were also influenced by depth of processing. The conclusions were derived from this study：(1) Foreground objects were highlighted in picture-text consistency judgment regardless of Chinese condition or English condition. (2) Language structures affected the properties of eye movements. (3) The depth of processing affected bilinguals’ scene perception.
Self-reference effect refers to the accelerated process and better memorization by the individual when the information is involved with self-concept. However, previous studies have focused only on categorical differences, considering self-relevant effects as behavioral or neural activation differences between self-relevant and non-self-relevant stimuli. Thus, they failed to take into account the degree of self-relevance. In real-life situations, different correlations usually lead to various personal meanings, as the process of highly self-relevant stimulus has a more significant physical and social meaning than that of the minimally one. In addition, there are researches showing that self-relevant information is associated with positive emotional valence, that the individual inclines to attribute positive results and traits to personal characteristics and accounts the negative results or traits unrelated with their own personal characteristics. Therefore, investigating the influence of positive emotion on self-reference process is of great value. We adopted picture-priming paradigm, presented emotional pictures and self-reference stimulus with participants. To be specific, each trial was initiated by a cross appearing at the centre of the screen for 200ms followed by a blank screen whose duration varied randomly from 500 ms to 1000 ms. Then a picture from one of the two emotional pictures categories was presented for 500 ms along with black screen lasting randomly for 150~300 ms in sequence. Afterwards, 500 ms self-reference stimulus and 1000 ms black screen emerged. Subjects were instructed to identify the color of self-referential stimulus as fast and accurate as possible. If the color is blue, press the “1” key; if it is green, press the “2” key. Stimulus words would disappear after a key press or automatically disappear after 1000ms. After the exercise experiment, the formal experiment concluded 360 trials divided into 3 blocks. Results of ERP showed that under positive emotional priming condition, the target stimulus elicited smaller P2 amplitudes than neutral condition, and highly self-relevant stimulus elicited a shorter P2 latency than any other stimulus. Furthermore, highly self-relevant names elicited larger N2 amplitude than moderately and non-self-relevant names, and under neutral priming condition, the target stimulus elicited longer N2 latency than positive emotional priming condition in frontal sites; highly self-relevant stimulus elicited longer N2 latency than any other stimulus conditions in the frontal and parietal sites. In the average amplitude of P3, highly self-relevant names elicited larger P3 amplitude than moderately and non-self-relevant names, and moderately self-relevant names elicited larger P3 amplitude than non-self-relevant names. Our results indicate human brain might not be sensitive on the processing of positive emotional stimulus. Self-referential processing demonstrates stability characteristics no matter whether in positive or neutral condition. Moreover, highly self-referential stimuli receive a more thorough and elaborate procession, with a representation of degree effect of self-referential processing.
Internal working models are based on young children’s expectations for the behavior of their attachment figures that develop into broader representations of their relational experiences, and decision rules about how to interact with others. These internal working models are thought to influence the child’s subsequent processing of social experiences and allow the child to anticipate, plan for, and adapt to his or her social world. Current research studies largely concentrated on the internal working models of attachment in childhood and adulthood; very little inquiry has been conducted on internal working models of preverbal infants and toddlers. It was not until 2007 that a study by Johnson, Dweck and Chen had found evidence for infants’ internal working models of attachment using a habituation paradigm. In addition, some theorists and researchers have indicated that maternal sensitivity is associated with internal working models in childhood; and also it has been suggested that maternal sensitivity may affect toddler’s attachment status. Therefore, internal working models may play an important role in relationship between maternal sensitivity and toddler’s attachment status. However, there is inadequate research on maternal sensitivity and internal working models in infancy. The present study explored the relationship between toddlers’ attachment status, maternal sensitivity and internal working models of toddlers. We hypothesized that toddlers of different attachment status might have unique patterns of expectations about their mother’s responsive behavior, and the expectations might correspond to maternal sensitivity in caregiver-infant interactions. Forty-one toddlers (M = 14.01 months, SD = 0.81) and their mothers from middle class backgrounds participated in the study. A visual habituation study using abstract animations with separation and reunion events was conducted to test a part of the toddlers’ internal working models—their expectations of a caregiver’s responsiveness. Toddlers’ attachment status was assessed by the Strange Situation procedure. Maternal sensitivity in caregiver–toddler interactions was measured by Maternal Behavior Q-Sort. The data was analyzed using repeated-measure analysis of variance, chi-square analyses, paired t tests, q-factor analysis and LCA. Results were as follows: (1) Toddlers’ expectations of a caregiver’s responsiveness depended on their own attachment status: insecure toddlers expected their caregivers to withhold comfort; (2) Toddlers’ expectations of a caregiver’s responsiveness depended on their mother’s behavior: the toddlers of Self-centered mothers expected caregivers to be unresponsive; (3) The results found by LCA indicated that there were two types of attachment system: Category 1, the toddlers of Child-centered mothers tended to expect their caregivers to be responsive, and showed secure attachment behaviors. Category 2, the toddlers of Self-centered mothers tended to expect their caregivers to be unresponsive, and showed insecure attachment behaviors in Strange Situation procedure. These results indicated that it was effective to using a visual habituation procedure to measure internal working models of preverbal toddlers. The claims that toddlers’ internal working models play an important role in the relationship between maternal sensitivity and toddler’s attachment status can be supported. If we want to change the attachment status of toddlers through their internal working models, we should pay attention to the behavior of their mothers.
Using the eye tracker, the present study was conducted to explore the cognitive process of problem finding of undergraduates in the contradictory and potential conditions, which focused on the four eye-movement areas of interest. Based on our hypothesis, we expected the quality and quantity of problem finding of two groups (high ability group and low ability group) would show significant difference in the contradictory and potential problem finding conditions, which would be reflected in the eye movement model. Furthermore, the eye movement characteristics would be correlated with the quantity and quality of problem finding. We think the analysis of eye track can show the eye movement rules which could not be reflected by the static indicators. The mixed design with 2 (question situation: a contradictory situation, a potential situation) ×2 (subject category : high ability group, low ability group) × 4 (interest areas: the first to the fourth interest area) was conducted in the study. The question situation and interest area were within-group factors, while the subject category was a between-group factor. The dependent variable included the quantity and quality of problem finding and the eye movement indexes (e.g. the fixation duration, fixation frequency, regression frequency, pupil diameter and eye track in the overall and four areas of interest). In the experiment, subjects were required to find problems in the contradictory and potential situations. The eye tracker recorded eye movement parameters when subjects found problems. The results were as follows. First, the average fixation duration in the potential situation was significant longer than the time in the contradictory situation, which may reflect that the cognitive processing in the potential situation was much more difficult than it in the contradictory situation. The pupil diameter size in the contradictory situation was bigger than it in the potential situation. The regression frequency for high ability group was more than that for low ability group, which indicated the positive role of the relationship and integration of information in the problem finding. Second, the eye movement in problem finding was significant different in the four areas of interest. In the region with essential information, many eye movement indexes raised, such as fixation duration, fixation frequency, and pupil diameter, which indicated subjects would put more effort. Particularly, the total fixation duration and fixation frequency in the second, third and fourth areas were more than these in the first area. The average fixation duration and pupil diameter size of undergraduates in the rear area were more than these in the front area. The regression frequency in the second area was more than it in the first area. In the contradictory situation, the total fixation duration, fixation frequency and regression frequency were correlated significantly with the quantity of problems, while the regression frequency was correlated significantly with the quality of problems in the contradictory situation. The regression frequency was correlated significantly with the quantity of problems in the potential situation. The relationship between the eye movement indexes and the quantity or the quality of problems in the areas of interest was almost the same with in total. Third, the fixation area matched the problem finding area which indicated the eye movement followed the thinking in problem finding. Searching behavior across area was observed in the first and the last fixation area which means the search for clues and final inspection and evaluation. High ability group spent less time in a stable fixation phase, which reflected their superiority of the flexibility in information conversion. For problem finding, the factors of group category and situation were reflected in eye movement indexes. Because of the differences in material property and difficulty, there was a significant difference of eye movement in the situation between each area of interest. All kinds of static eye movement indexes could better reflect the quantity rather than the quality of problem finding. However, the regression frequency was a sensitive index of reflecting the problem-finding ability, and the analysis of the dynamic eye track revealed the rules that a single static index cannot. Overall, using the eye tracker to investigate the cognitive process of problem finding could not only improve the accuracy of the experimental research, but also conduce to deeply explore the internal information processing mechanism of problem finding.
Several previous studies consistently reported that children with Autistic Spectrum Disorder (ASD) had impairments in referential word learning when they are provided with only social eye gaze cues. More recent studies, however, suggested that children with ASD could use a speaker’s gaze direction to learn words when there were abundant additional perceptual cues enhancing the salience of the referent object. But their findings could not exclude the possibility that children in these studies just relied on perceptual cues to guide their word learning without noticing any social cues. In addition, it is also unknown that how ASD children in late childhood should respond when social cues conflict with perceptual cues. In order to examine the relative roles of social cues on word learning task compared to perceptual cues, the study recorded the eye movements of 18 verbally able children with ASD (M ages = 134.83 months) and their typical developing peers matched on receptive language and non-verbal intelligence (M ages = 71.61 months) while these two groups were completing word learning tasks under the following conditions: when gaze cues were no provided (No Gaze condition), when gaze cues were consistent with perceptual cues (Consistent Gaze condition), and when gaze cues were inconsistent with perceptual cues (Inconsistent Gaze condition). We found that, like typically developing (TD) children, children with ASD would map the novel word to the interesting object in the No Gaze condition and in the Consistent Gaze condition and the performance in the Consistent Gaze condition was better than that in the No Gaze condition. We also found that the ASD children would overlook perceptual cues to follow the speaker’s attention focus to pick up the boring object in the Inconsistent Gaze condition. Eye movement data results showed that: 1) the correct rate of first gaze following (the first saccades from face to target objects/ the first saccades from face to target and non-target objects) and the frequency of gaze following (saccades from face to target objects) in ASD children were lower than TD children; 2) the proportion of duration on eye region (fixation to eye region/ fixation to face region) in ASD children was higher than TD children; 3)there were no differences between two groups in the proportion of fixation to interesting object (fixation to interesting objects/ fixation to interesting and boring objects) and the proportion of gaze following (saccades from face to target objects/ saccades from face to target and non-target objects). The results illustrated that although social cues facilitated word learning in autism in overlapping cues condition and children with ASD also weighted social cues more heavily than perceptual cues, the style of capturing social cues in ASD children were different from TD children. They could not flexibly distribute attention resource according to the change in social scene, captured social information with the analytic way of feature process, and lacked the sensitivity of social information and the understanding of social meaning of social information.
The suggestion of individual differences in fear conditioning has been put forward as a potential etiological factor for the development of anxiety disorders. Previous studies mostly focused on investigating the differences in fear acquisition and extinction comparing anxious and non-anxious individuals, and different theories were developed for possible explanations. However, to provide evidence for a causal link between anxiety and fear conditioning, anxiety should be experimentally induced in healthy individuals. And to further understand the mechanism of anxiety and fear conditioning, evaluative conditioning should also be explored. An experiment was designed to test the impact of anxiety on fear conditioning. Forty-four healthy female participants were exposed to a psychological social stressor (or control condition) while subjective anxiety was measured, then all participants participated in a differential fear conditioning experiment consisted of habituation, acquisition, and extinction phases while subject US-expectancy was rated online. Two simple geometrical figures served as CS+ and CS?, and a 4-sec female scream as US. Each CS+ was paired with a US during the acquisition phase. To measure evaluative conditioning, participants were required to rate CS-valence at the end of each conditioning phase. The results showed that exposure to the stressor increased state anxiety. During acquisition, state anxiety inhibited discriminative conditioning between CS+ and CS?. Specifically, the anxiety group exhibited lower subjective US-expectancy ratings for CS+, but higher subjective US-expectancy ratings for CS? compared to control group. At the phase of extinction, state anxiety led to a deficit in extinction learning. The impact of state anxiety was also found in evaluative conditioning. The anxiety group showed more negative valence ratings for CS compared to control group in habituation and extinction phases. The results of this study support the theory, which identifies the failure to inhibit fear responses in the presence of safety signals (a CS?) in anxiety individuals. The results suggest that anxiety hinders the individuals’ ability to distinguish between safe and unsafe signals, and in turn impairs the adaptive response to threatening stimulus in a changeful environment. The results also show that anxiety attenuates the normal recovery process from aversive experiences, which indicates that individuals in an anxiety state would need more extinction trials (or exposure session) than individuals in a neutral emotional state. In addition, the relation between US-expectancy and CS-valence suggests that successful exposure therapy should be more focused on the changing of the individuals’ negative evaluation reactions of CS.
Social comparison is a mental process through which people come to know themselves by evaluating their own abilities, attitudes, outcomes and believes in comparison with others. Previous studies found that social comparison influenced the evaluative process of the outcome in the brain. However, in all those studies, social comparison was manipulated as the comparison between the rewards of two participants, so it remains unclear whether the monetary value or the comparison affects the outcome evaluation. By dissociating the monetary value from comparison, the current study aimed to investigate how non-monetary social comparison affects the process of outcome evaluation in a cooperative task. Eighteen healthy undergraduates (10 males, 8 females) took part in the EPR experiment. Participants cooperated with a confederate to complete a gambling game on two connected computers. Each of them chucked one dice sequentially and randomly. If the numbers on the two dices totaled greater than 6 in the trail, they would win 1 yuan in the trial; if not, they would lose 1 yuan. The final reward would be portioned out equally between them. After they chucked the two dices, a “>” or “<” between their name cueing comparison feedback indicates which one get a larger number. Then a feedback screen informed about whether they win or loss. However, unknown to the participants, the feedback was independent of their performance. Trails of each conditions were equal. Both social comparison feedback and monetary feedback were included in the final statistical analyses. For FRN analysis, we measured the average amplitude in the 250-350 ms time window for the social comparison feedback and the monetary feedback. P300 amplitude was quantified as the positive peak in the time window of 300-600 ms after feedback onset. ERP results revealed that FRN and P300 were both sensitive to non-monetary social comparison. When compared with those who had a better performance, participants who got a smaller number showed a larger FRN and a smaller P300. FRN amplitude of gain was more negative than that of loss. P300 showed an opposite pattern relative to FRN. Social comparison did not affect the process of outcome evaluation of the cooperative task. These findings suggest that the encoding of social comparison occurs at the early stage of the outcome evaluation. And FRN could code not only the prediction errors for monetary reward but also the information in the social context. Our results also indicate that FRN responds to the most notable information in the current context.
Trustees’ trustworthiness is a precondition of other people trusting in them, which may be influenced by trustees’ social identity complexity. Previous literature has revealed the impact of single social identity on trustworthiness; however, few studies have examined how the multiple social identities of a trustee affect his or her trustworthiness rated by others. The structure of multiple social identities can be measured in terms of social identity complexity, a concept proposed by Roccas and Brewer in 2002, which refers to the way in which individuals subjectively represent the relationships among their multiple ingroup memberships. Concretely, individuals with low social identity complexity see their ingroups as highly overlapping and convergent, whereas those with high social identity complexity see their different ingroups as distinct and cross-cutting membership groups. Roccas and their colleagues merely concerned how individuals perceive their own social identities, but neglected how they represent other people’s social identities. Moreover, social identity complexity not only reflects humans’ mental representation of their own or others social identities, but also represents one’s factual quantity of social identities. In our opinion, the quantity of social identities can be defined as an index of objective social identity complexity, which role has never been paid attention to. The present study expanded Roccas and Brewer’s ideas of social identity complexity and examined how trustees’ objective social identity complexity (single social identity vs. multiple social identities) affected people’s judgment towards trustees’ trustworthiness. In Study 1, we tested the main influence of trustees’ social identity complexity on their trustworthiness. The experiment was carried out in sleepers of a train traveling from Beijing to Yantai city. Sixty train passengers were enrolled and randomly assigned into two conditions to read a news report about a Volkswagen car (a middle-class brand) crash respectively: one group read the report depicting the driver’s single social identity (low complexity), whereas, the other group read the report depicting the driver’s multiple social identities (high complexity). After reading, they rated the driver’s trustworthiness and social distance between themselves and the driver (trustee). The results showed that trustees’ high social identity complexity effectively reduced social distance, and led participants give a higher remark on trustees’ trustworthiness. That is to say, social distance mediated the impact of trustees’ social identity complexity on their trustworthiness. In Study 2, we examined the moderating effect of trustees’ group category on the impact of social identity complexity and social distance on their trustworthiness. One hundred and twenty college students were randomly assigned into one of four conditions in a 2 (trustees’ social identity complexity: high vs. low) × 2 (trustees’ group category: ingroup vs. outgroup) full-factorial design. The experiment materials in this study were same to Study 1, except that we used two distinct car brands (ALTO vs. BMW) to manipulate trustees’ group category (ingroup vs. outgroup). More specifically, ALTO as an under-class brand, its driver would be perceived by college students as an ingroup member; whereas, BMW as a top-class brand, its driver would be an outgroup member. The results confirmed the findings of Study 1 that trustees’ social identity complexity had a positive effect on their trustworthiness and the relationship between the two variables was mediated by social distance. Moreover, the main effect of social identity complexity and the mediating effect of social distance were moderated by the group membership of trustees, and the two effects merely occurred for outgroup trustees rather than ingroup trustees. The present study provided new findings about the correlates of trustees’ trustworthiness, more importantly, which enriched the theory of social identity complexity and previous research. Besides the theoretical contributions, the present study also had great practical implications for making people’s judgment objective and promoting the positive intergroup relationships.