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ISSN 0439-755X
CN 11-1911/B

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    30 November 2007, Volume 39 Issue 06 Previous Issue    Next Issue

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    Inhibition of Return on Three-dimensional Slant Plane
    Shen-Mowei,Gao-Zaifeng,Zhang-Guangqiang,Shui-Rende,Qiao-Xinxi,Li-Weijian
    2007, 39 (06):  951-958. 
    Abstract ( 2124 )  

    Introduction
    Inhibition of return (IOR) has been a major research focus in the field of attention since Posner and Cohen (1984) discovered this phenomenon. There are two main views on the generation of IOR. The first view is postulated by Posner and Cohen (1984), which claims that IOR is the withdrawal of attention from a location that leaves an inhibitory tag. The second view is that IOR has a close relation with oculomotor system (Rafal, et al, 1989), and that superior colliculus plays a very important role (Sapir & Soroker, 1999). Both views have obtained much support. However, all the previous research used the cue-target paradigm in the two dimension space, in which a cue was displayed first to indicate a peripheral location before the target appeared. In this paradigm, the cue would lead to attention shift as well as a saccade (or a saccade plan), so the previous research on IOR generation could not separate the attention factor from oculomotor factor effectively. To eliminate saccade’s contribution to IOR, we explored the generation of IOR by using random dot stereogram with slant information as material.
    Method
    Sixteen individuals participated in the study. Two experiments were conducted using a three dimension spatial cue-target paradigm. First, a random dot stereogram was displayed in the center of the screen as a cue, and the participants were asked to pay attention to the slant orientation of the plane. Then a target displayed in the center of screen with the same or different slant orientation as the cue, and the participants were required to respond to the target’s slant orientation. Thus, in this paradigm the participants did not need to make saccades or saccade plans to complete the task. We varied the consistency of orientation and angle between focused plane and tested plane in experiment 1 and 2. We also varied the consistency of orientation and angle between unattended plane and tested plane in experiment 2. . ANOVAs were performed in both experiments.
    Results
    The data analyses showed that the response to the plane having the same orientation with the cuing focused plane was much lower than that with different orientation. The response to the plane having the same orientation with cuing unattended plane was much slower than that with no cuing plane at all.
    Conclusions
    The results suggested that there was attention-related inhibition of return in three dimension space which was formed by disparity. Both the focused plane and the unattended plane led to IOR, but the former condition had a greater inhibition effect. The results support that inhibition of return is related to attention.

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    The Effects of Stimulus Type and Consistency of Representation on Inattentional Blindness
    Li Huijie,Wo Jianzhong,Liu Hanhui,Zhao Liqin
    2007, 39 (06):  959-965. 
    Abstract ( 2392 )  
    The study of attentional capture has focused primarily on measuring the effect of an irrelevant stimulus on task performance, termed implicit attentional capture. In essence, these studies explore how well observers are able to ignore something that they expect but know to be irrelevant. By contrast, several new paradigms that explore the same issue have found unexpected objects often fail to capture attention, termed “inattentional blindness.” Many researchers are extremely interested in this field and have consequently conducted many researches related to this subject. They have explored (1) the effect of stimulus familiarity, size, location, and distance; (2) the similarity between attended and unattended stimuli; (3) the zone of attention; (4) perceptual load; and (5) expectation and expertise on inattentional blindness. The current study aims to examine the effect of stimulus type and consistency of semantic representation on inattentional blindness.
    The study employed a two-factor mixed design. The participants comprised 40 subjects who attended the baseline tests involving pictures and words and 52 subjects who attended the inattentional blindness experiment. The attended stimulus type was the between-subject factor, while the consistency of semantic representation was the within-subject factor. The attended picture group and attended word group each included 23 valid subjects. Using superimposed picture and word streams, we explored the effect of stimulus type and consistency of semantic representation on inattentional blindness. An ANOVA was performed to analyze the results. We explored the baseline recognition score of pictures and words; moreover, we compared the inattentional blindness scores with baseline scores.
    The results showed that in comparison to baseline scores, inattentional blindness was significant when the superimposed pictures and words were presented. Regardless of whether the attended stimuli were pictures or words or whether the representation between the pictures and words was consistent, Subjects were able to detect words more easily when the words and pictures had the same semantic representation. In addition, unattended stimuli captured the attention of subjects more easily when they had the same semantic representation as the attended stimuli.
    Inattentional blindness provides a new visual angle for the research of attentional capture. Traditional implicit paradigms explore how well observers are able to ignore something that they expect but know to be irrelevant, whereas in explicit attentional capture, the critical question is how likely are subjects to notice something that is potentially relevant but unexpected. In this research, we found that meaning was an important factor in attentional capture. Moreover, the results provided some useful suggestions for advertisements. If advertisement producers would like the audience to be influenced by their advertisements, then they should display pictures that the audience is interested in and subsequently, in the background, present their products using words. Furthermore, for better attention capture, the representation of objects using both pictures and words is recommended
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    Effect of Conflicting Reference Frames on Image Updating
    Liang Sancai,You Xuqun
    2007, 39 (06):  966-976. 
    Abstract ( 2112 )  
    Introduction: When an individual moves in an environment, his or her cognitive system must simultaneously update information pertaining to the spatial relations between the environment and his or her body; this is termed as spatial updating. Similarly, when an individual imagines himself or herself or the surrounding objects to be rotating, the representation of the spatial relations between him or her and the surrounding objects will be updated; this is known as image updating. Wraga et al. (2000) found that egocentric image updating had an advantage over array-centered image updating. Further, Zack et al. (2003) found the different brain activation patterns between them. This suggested that there were two different processing subsystems underlying both egocentric and array-centered image updating. Based on the conflicting-of-reference model of spatial updating, developed by Presson et al. (1987), the present study aims to examine whether conflicting reference frames influence egocentric and array-centered image updating, and if so, how can it be realized.
    Method: The study included four experiments that were attended by 64 undergraduates, aged between 18 and 23. The participants were unaware of the purpose of the experiments; further, all participants had normal or corrected-to-normal vision. Acting as stimuli, 3D pictures representing a scene were drawn using 3ds max 6.0 software. Stimulus presentation and data collection were controlled by a Lenovo microcomputer using the E-Prime software. The effects of conflicting reference frames under the baseline condition were tested in experiment 1. In experiment 2 to 4, conflicting reference frames were systematically manipulated to explore their effects on the two kinds of image updating.
    Results: The results indicated the following. First, conflicting reference frames had significant effects on egocentric image updating; however, in comparison, they had comparatively minor effects on array-centered image updating. As a result, the self-rotation advantage of image updating decreased gradually, and eventually disappeared. Second, the effect of conflicting reference frames caused by tilted observers was unequal to that caused by tilted scenes in that the former was smaller than the latter. Finally, the effect of conflicting reference frames on array-centered image updating diminished if a local spatial reference frame was included in the scene and was tilted at the same angle as the scene. However, at the same time, the effect of conflicting reference frames on egocentric image updating was unaffected by this experimental manipulation.
    Conclusions: The results suggest that there were different cognitive mechanisms underlying egocentric and array-centered image updating. Moreover, the results extended the conflicting-of-reference model developed by Presson et al
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    Two Color-Based Top-Down Processes in Preview Search
    Cui Xiangyu,Xu Baihua
    2007, 39 (06):  977-984. 
    Abstract ( 1510 )  
    Preview search is one of the new focuses in attention selection research in the last few years. In preview search task, a subset of distractors appears at least 400 ms ahead of the second subset, which may include the target. The time to search the target can be almost foreign to the number of the former distractors, only depending on the latter. This phenomenon is termed Preview Effect. The most acceptant interpretation on Preview Effect is the Visual Marking theory (Watson & Humphreys, 1997). According to this theory, the former distractors can be ignored or “marked” by top-down inhibition, which is based on the locations of the items. However, Braithwaite et al (2004)’ claimed that the inhibition was not only location-based, but also feature-based. They found some evidences by manipulating color proportions in both former and latter subset. This study designed a new method to certify the role of color in Preview Effect, called colored probe-dot technique. Using this method, a direct color process effect could be observed, without altering the color proportions in both subsets, which may alter the original pattern of preview search.
    This study included two experiments, combining preview search task and colored probe-dot task. In both experiments, first a group of preview items were displayed followed by a probe-dot or a group of search items, depending on whether a sound clue appeared in the advance. In the first experiment, the color of probe-dot was that of the preview items or the irrelevant one, while in the second experiment, the color of the search items and the irrelevant color are the alternatives. 14 subjects participated the first experiment, and 16 subjects participated the second, all had normal or corrected-to-normal visual acuity and normal color vision.
    The results showed that subjects detected the irrelevant-color probe-dot faster than the preview-item-color probe-dot in the first experiment, and a weak location effect was also observed. In the second experiment, the reaction time to the search-item-color probe-dot is shorter than the irrelevant-color probe-dot, no location effect showed.
    We deduce that there are probably two kinds of color-based top-down processes, one is the inhibition set of the preview items’ color, and the other is the anticipatory set of the search items’ color. A location-based inhibition may play an important role in preview search too, depending on dissimilar task situation. The existence of color effect indicates Gestalt organization clues can greatly facilitate preview search. Besides different colors between former and latter subsets, temporal grouping and search array configuration are regarded Gestalt organization clues too
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    The Endogenous Preparation and Exogenous Adjustment
    of Switching Process in Working Memory
    Guo Chunyan,Sun Tianyi
    2007, 39 (06):  985-993. 
    Abstract ( 520 )  
    Switching process is an important aspect of executive control. The process is presented as controlling switching course between two tasks which compete the same cognitive resources in working memory. The course of switching involves both endogenous preparation without an external stimulus and exogenous adjustment in response to the external stimulus. But what is the general way to deal with information is not clear.
    A “Task—switch” paradigm was used in this study to investigate the switching process in behavioral experiments. Tasks consisted of a simple classification of Chinese words (noun /verb) or digits (odd /even). For each task, a stimulus picture consisted of a background, one-word Chinese and a two-digit natural number. The task to be performed was indicated by the color of the background (If the color is red, the task is a digit task, and if it is blue, the task is a Chinese-word task). We explored the switching process under foreknowledge conditions in experiment 1. Participants performed two tasks consecutively (task one and task two) that were either the same (task repetition) or different (task switch), and there were three blocks for both task repetition and task switch. All the blocks were presented by the sequence of ABBAAB. In experiment 2, we studied the switching process under no-foreknowledge condition. There were six blocks of stimulus and each block mixed with the trials of task repetition and the trials of task switch randomly. All the blocks were presented in a quasi-random sequence. The presentation (version 0.81) was used to compile the experimental procedures and the 17 inches (1024×768) Dell monitor was used to display stimuli. Thirty healthy and right-handed undergraduate students (12 men and 18 women) from the Capital Normal University participated in the experiments 1 and 2 respectively. The students’ eyesight or corrected eyesight was normal, and their ages ranged from 19-24 years (averaged:20.03). A repeated measure ANOVA was performed to analyze the data.
    The results suggested: 1.The task repetition and task switch were different courses. The time of task repetition effect was significantly longer than that of task switch effect, under the condition of foreknowledge or no-foreknowledge; 2. The hypothesis was confirmed that endogenous preparation and exogenous adjustment were two different courses of switch process; 3. Under the conditions of foreknowledge task repetition, foreknowledge task switch and no-foreknowledge, the influence of task two on task one was different. There was a prospective memory effect in this course.
    Comparing the results of experiments 1 and 2, we conclude that the general way of the switching process in dealing with information as an important aspect of executive control is that under the condition of foreknowledge, switching process beginning with endogenous preparation after task one is clear, and is accomplished via exogenous adjustment after task two is presented. In the case of no-foreknowledge, however, switching process can be accomplished only by relying on the exogenous adjustment
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    Processing Mechanisms Underlying Event-based Prospective Memory: Evidence from an ERP Study
    Chen Youzhen,Ren Guofang,Yuan Hong,Huang Xiting,Chen Youguo,Yue Caizhen
    2007, 39 (06):  994-1001. 
    Abstract ( 1118 )  
    Prospective memory (PM) is the memory for actions to be performed in the future. There are several theories on the processing mechanisms underlying event-based prospective memory, such as the simple activation model, noticing-search model, preparatory attentional processes and memory processes theory, and multiprocess view. They differ from one another on whether PM uses cognitive resources at retrieval. Using behavioral experiments, previous researches have generally examined how a PM task interferes with a background task and have achieved inconsistent results. The present article aims at testing these theories, using the event-related potentials (ERPs) technique.
    In this experiment, 20 junior undergraduates (10 women, 10 men) aged 19~26 years participated as paid volunteers. All participants were healthy, right-handed, and had normal or corrected to normal vision. Further, a typical paradigm for studying processing mechanisms underlying PM was used in this experiment. A triangle and a polygon were presented together in each trial. In the background task, participants were required to judge whether the polygon was on the left-hand side or on the right-hand side. In the PM task, participants were supposed to complete the background task; moreover, if the triangle was blue, they were required to determine the number of sides of the polygon and press a specified key if the number of sides was 5 or less and another key if it was more than 5. A session of the control condition involving only background trials was included at the beginning of the experiment, before participants had received any instructions concerning the PM trials. Subsequently, in the experimental condition, a PM task was administered to each participant. Brain electrical activity was recorded from 64 scalp sites.
    As a function of non-PM trials, the accuracy and reaction time data in the two conditions were compared. The results indicated that the reaction time in the experimental condition was significantly longer than that in the control condition. The findings suggest that perhaps in the PM task, the participants were involved in strategic monitoring processes before the target event occurred. Data from the ERPs recorded during the non-PM trials suggest that there were significant differences in the time windows of 200~300 ms, 300~350 ms, and 350~400 ms after the onset of the stimulus. The ERP difference wave (subtracting the experimental condition from the control condition) showed the maximum amplitude over the central site (Fz) with a peak latency of 250 ms (N250). The topographic map in the time window of 200~300 ms indicated that the components mainly activate the frontal lobe.
    These results might support the preparatory attentional processes and memory processes theory and partially support the multiprocess view. However, they fail to support the predictions derived from the simple activation model and the noticing-search model. Further, the possibility that PM retrieval might rely on multiprocess is discussed. The present results provide electrophysiological evidence for potential mechanisms underlying event-based prospective memory
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    Attentional Modulation of Time Perception: An ERP Study
    Chen Youguo,Zhang Zhijie,Guang Xiting,Guo Xiuyan,Yuan Hong,Zhang Tian
    2007, 39 (06):  1002-1011. 
    Abstract ( 2611 )  
    Previous researches have indicated that attention can modulate subjective time perception: the less the attention distributed to duration, the more the chances of time being misperceived. Most brain mechanism studies have focused on the comparison between temporal and nontemporal conditions. These studies were confined to the attention shift between temporal and nontemporal attributes, and did not refer to the process of attentional modulation of time perception. A recent research studied the cerebral areas concerned with the attentional modulation of time perception using functional magnetic resonance imaging (fMRI). The study employed a dual-task paradigm in which attention was distributed differently between the time and color of the visual stimulus. However, the dynamic process of attentional modulation of time perception was still unclear because of the low temporal resolution of the fMRI. In contrast, this experiment used event-related potentials (ERPs) to investigate this process.
    Nineteen volunteers participated in this experiment. All subjects performed a training session at least two days before the formal experiment. An attentional cue directed the subjects to selectively attend to (1) the stimulus time (T condition), (2) the time rather than the pitch (Tp condition), (3) both parameters equally (tp condition), (4) the pitch rather than the time (tP condition), or (5) the pitch (P condition). Effective attentional allocation was obtained by varying the relative likelihood of trials involving time distinguishing or those involving pitch distinguishing. The reaction time, error rate, and event-related potentials were recorded simultaneously by computers during the experiment.
    The electroencephalogram (EEG) was recorded from 64 scalp locations of the extended 10–20 system, using an electrode cap (Brain Product Inc.) with Ag/AgCl electrodes. Linked mastoids were used as the reference, and a ground electrode (GND) was placed on the medial aspect of the frontal lobes (on the middle line, between FZ and FCz). An estimation of the dipolar sources of the T-P difference waveform was performed using the Brain Electrical Source Analysis program (BESA version 5.0), which is based on the four-shell ellipsoidal head model. Further, a principal component analysis (PCA) was employed in the interval from 300 to 540 ms in order to estimate the minimum number of dipoles. Finally, a genetic algorithm was used to determine the location of the dipoles.
    Behavioral data showed that the subjects allocated their attention to the time and pitch based on the attentional cues. The ERP data indicated the following: (1) the main effect of the attentional conditions in the amplitude of P2 was not significant, but the difference between the T and P conditions was significant in the multiple comparison; (2) the main effect of the attentional conditions in the average amplitude of the contingent negative variation (CNV) was significant from the start latency time to 540ms, and an increase in the attention to time augmented the average amplitude of the CNV; (3) the map of the T-P difference waveform showed that the maximal amplitude of the difference waveform was located on the areas of the frontal, center, and parietal lobes; and (4) the dipoles of the T-P difference waveform were located on the supplementary motor area (superior frontal gyrus, middle frontal gyrus) and the inferior parietal lobule.
    These results have the following implications: (1) the time information process exists in P2 phase; (2) CNV reflects the attentional modulation of time perception, which is an index of the existing controlled process; (3) the supplementary motor area may play a key role in time perception with cross-modal effect; and (4) the inferior parietal lobule is also related to the attention of time, albeit time attention is not the only attribute. However, these results are contradictory to Lewis’ notion that (1) a “second” is the boundary between an “automatic” and a “cognitively controlled” timing system and (2) the supplementary motor area belongs only to the “automatic timing system.”
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    The Impact of the Articulary Loop and Visuospatial Sketchpad
    on Phonemic and Semantic Fluency
    Zhang Jijia,Lu Aitao
    2007, 39 (06):  1012-1024. 
    Abstract ( 1929 )  
    Verbal fluency is typically measured by generative naming tasks. The two types of verbal fluency that are generally tested are (1) phonemic fluency, in which the subjects generate words beginning with a particular letter, and (2) semantic fluency, in which the subjects produce items from a specified category. Most of the previous studies primarily focused on the contribution of the central executive function to phonemic and semantic fluency; however, little attention was paid to the contribution of the phonological loop and the visuospatial sketchpad.
    Based on the work of Rende, the present study explored the effects of the articulary loop and visuospatial sketchpad on verbal fluency. The following two types of secondary tasks were used: (1) articulatory suppression and sound judgment and (2) grapheme judgment and rotation judgment.
    Methods
    Forty four undergraduates, including 22 women, participated in Exp.1. The writing speed of all participants was estimated. Subsequently, the participants were given a familiar topic, such as “my college life,” and were required to write as many words as possible in one minute. All of them produced more than 30 words per minute, which satisfied the experimental requirement. Thereafter, they were required to assess their Chinese language level based on a 5-point scale. The scores of all the participants were equal to or higher than 3. Exp. 2 involved 40 subjects, including 20 women. The participants were given the same topic as Exp.1 and were required to talk on the subject for one minute in order to test their oral speed. They spoke rather fluently and none of them stuttered or spoke slowly. Similar to Exp. 1, the Chinese level of all participants was equal to or higher than 3. Both experiments employed a two-factor within-subject design, 2 (phonemic and semantic fluency) × 2 (single- and dual-task conditions).
    Results
    (1) The results of Exp.1 indicated that the articulatory loop had a substantial impact on verbal fluency. When the secondary task was articulatory suppression, the participants produced more words during the semantic fluency task than during the phonemic fluency task; however, they produced fewer words in the dual-task condition than in the single-task condition. Further, the cluster size was smaller in the dual-task condition than in the single-task condition. The participants generated more switches during the semantic fluency task than during the phonemic fluency task; however, they generated fewer switches in the dual-task condition than in the single-task condition. When the secondary task was sound judgment, the pattern of results was similar to that when the secondary task was articulatory suppression, with the exception that there were no significant differences in the cluster sizes across the different tasks and different conditions. Therefore, the negative impact of articulatory suppression and sound judgment was significantly stronger for the phonemic fluency task than for the semantic fluency task.
    (2) The results of Exp.2 indicated that visuospatial sketchpad had a substantial impact on verbal fluency. When the secondary task was grapheme judgment, the participants produced more words during the phonemic fluency task than during the semantic fluency task; however, they produced fewer words in the dual-task condition than in the single-task condition. Further, the cluster size was larger in the semantic fluency task than in the phonemic fluency task. The participants generated more switches during the phonemic fluency task than during the semantic fluency task; however, they generated fewer switches in the dual-task condition than in the single-task condition. When the secondary task was rotation judgment, the pattern of results was similar to that when the secondary task was grapheme judgment. Therefore, the negative impact of grapheme judgment and rotation judgment was significantly stronger for the semantic fluency task than for the phonemic fluency task.
    (3) A detailed analysis showed that Chinese subjects adopt different strategies in different fluency tasks, using the oral verbatim and reading silently strategies for phonemic fluency tasks and the mental image strategy for semantic fluency tasks.
    Conclusions
    (1) Articulatory suppression and sound judgment tasks influenced phonemic verbal fluency more than semantic fluency.
    (2) Grapheme judgment and rotation judgment tasks influenced semantic fluency more than phonemic fluency.
    (3) The strategies adopted in phonemic fluency tasks reflected language&nb
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    The Patterns and Function of Information Representation in Stereotype
    Wang Pei,Yang Yaping
    2007, 39 (06):  1025-1033. 
    Abstract ( 729 )  
    Information is organized on the principle of valence-consistency in the stereotype representation according to the study of Quinn et al. (2004). In their study, however, they simply studied two neutral stereotypes. If there was an extremely strong positive or negative stereotype towards a group, was information still organized in way mentioned above? Given this, this paper studied in detail the patterns of information representation in stereotype and its function by choosing stereotypes of three professions with different valences(namely positive, neutral and negative). At the same time, the paper verified the following hypotheses: The pattern in which positive information integrated with the positive one while the negative one with the negative one was available in the information representation of stereotype. The pattern had a parallel facilitation-inhibition effect in social cognition.
    This study used retrieval-practice paradigm and recognition paradigm to probe the above hypotheses. 288 subjects were randomly chosen from one university. The procedure of the experiment was planned by a computer program designed with VB 6.0. The experiment was divided into 5 stages, namely, stimulation, study, retrieval-practice, distraction and recognition.
    The results verified the following hypotheses: Regardless of the valence of stereotypes, the patterns of information representation adhered to the principle of valence-consistency, i.e. positive information integrated closely with the positive one while the negative one with the negative one. Besides, some unexpected results were found, i.e. the retrieval for negative information and the features related to women is better.
    This study has important implications in the theory of social cognition. It tested for the first time the patterns of information representation in stereotype and its function; it shows that, when there are conflicts among stereotypes towards a target, the process of facilitation and that of inhibition function together, which make it possible that a consistent judgment is formed by only using fewer cognitive resources; the results of this study tested the typical preference for the negative information and prejudice against women in the course of social perception.
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    Effects of Chronic Stress on Behavior and Heat Shock Protein 70
    Wang Weiwen,Shao Feng,Liu Mei,Sun Meng,Lin Wenjuan
    2007, 39 (06):  1034-1040. 
    Abstract ( 1990 )  
    Chronic stress can suppress organisms’ resistance to adverse stimuli in the environment. The stress responses occur at both the system and single-cell levels. Although many studies have investigated the neuroendocrine mechanisms underlying the effects of stress on health, the characteristics of cellular stress response are still poorly understood. One manner in which cells resist damage and/or death induced by stress is to synthesize a highly conserved set of intracellular proteins, termed heat shock protein (HSP). In particular, the 70-kDa HSP (HSP70) is essential for cellular recovery after stress as well as survival and maintenance of normal cellular function. It has been demonstrated that the expression of high levels of HSP70 is associated with an increased resistance of cells to challenges that would otherwise lead to cell injury and/or death. Therefore, the intensity of an HSP70 response to stress is an important biomarker of how the cell tolerates stress damage.
    This study aimed to determine whether prior chronic stress inhibited the synthesis of HSP70 in immune cells in the peripheral blood and spleen of rats exposed to an acute hot water bath. Twenty-eight rats were randomly divided into 2 groups with 14 rats in each group: the control group (C) and the chronic stress group (CS). CS rats were exposed to chronic unpredictable stress for 4 weeks to induce depressive-like behavior. The controls were stress-free. Thereafter, 8 rats in each group were exposed to acute heat stress (C-heat shock and CS-heat shock) to induce whole-body hyperthermia (maintaining the core temperature at 41°C for 25 minutes).The other rats remained undisturbed in their home cages (C-no heat shock and CS-no heat shock). All rats were decapitated 6 hours after the completion of the treatments. The blood and spleen were collected and the level of HSP70 expression in the leukocytes was measured using flow cytometry.
    It was found that CS rats showed a decreased cellular HSP70 expression following the heat treatment, while a significant increase in the synthesis of HSP70 was observed in all types of immune cells from C rats. However, in CS rats, such HSP70 changes were only detected in the monocytes and granulocytes. Further, the increasing degree of heat-induced cellular HSP70 expression in CS rats was less pronounced than that observed in C rats.
    These results demonstrated that chronic stress decreased heat-induced HSP70 response in immune cells. Further, they suggested that the deficit of HSP70 might be involved in the suppressive modulation of the immune function induced by chronic stress.
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    Animal Research on Immunity Activation-Induced Depressive-Like Behavior: Doses and Time Effects

    Pan Yuqin,Wang Donglin,Lin Wenjuan

    2007, 39 (06):  1041-1047. 
    Abstract ( 1089 )  
    The “cytokine theory of depression” indicated that cytokines induced by immunity activity are not only immunity mediators but also play an important role in the mechanism of depressive-like behaviors. The administration of lipoposaccharide (LPS), which is a product of the cell wall of gram-negative bacteria, is known to activate immune functions and induce the release of several cytokines both in the periphery, and the brain such as frontal cortex, hippocampus, and hypothalamus that are considered to be the essential brain regions of depression. Many studies found that the administration of LPS could induce depressive-like behavior, such as a decrease in the preference of sweet milk, low locomotion, and anorexia. However, these researches only pay attention to short-term behavior effects; the effects of LPS administration on long-term behavior changes have not been clearly reported. To further understand the role of immunity activation-induced cytokines in depression, the purpose of the present study was to investigate the effects of repeated administration of LPS in different doses on behavior and the long-term behavior effects in rats.
    Method
    Fifty rats were randomly divided into 4 LPS groups (LPS400, LPS200, LPS50, and LPS10) and 1 saline control group (LPS0); each group comprised ten rats. According to the groups, the rats were injected intraperitoneally with LPS 400 μg/kg, 200 μg/kg, 50 μg/kg, 10 μg/kg, and saline, respectively; they were injected again after 3 days. Two hours, 24 hours, and 48 hours after every injection, the rats were subjected to a saccharin preference test, an open-field test, and an elevated plus-maze test.
    Results
    The results indicated that 2 hours after the first LPS injection, the percent of saccharin preference, locomotion and upright activity in the open-field test, and open arms and closed arms entries in the elevated plus-maze test were significantly lower in LPS50, LPS200, and LPS400 than in the saline control group (percent of saccharin preference: p < 0.01; locomotion: p < 0.01; upright activity: p < 0.01; open arms entries: p < 0.01; and closed arms entries: p < 0.01). It was also found that the LPS-treated rats had fewer open arms entries than the saline controls 2 hours after the repeated LPS injection (p < 0.01). However, there was no significant difference between the LPS-treated groups and the saline control group with respect to behavior changes 24 hours and 48 hours after the first LPS injection and after the repeated LPS injection. In addition, there were no differences among LPS400, LPS200, and LPS50 at any given point of time.
    Conclusions
    Our results demonstrate that LPS-induced immunity activation can result in evident depressive-like behavior in animals. However, no significant long-term effect in behavior was found. Thus, the present results suggest that LPS-induced proinflammation cytokines may be one of the conditions, but not the only condition or sufficient condition that causes the long-term depression. Using the animal model of LPS-induced depression has certain limitations.
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    Interactions of MK-801 and Environmental Cues on the Behavioral Sensitization Induced by Morphine
    Yu Bin,Li Xinwang,Wang Jia,Wang Lei,Ren Limin
    2007, 39 (06):  1048-1054. 
    Abstract ( 1967 )  
    Many laboratories have reported that co-administration of N-methyl-D-aspartate (NMDA) receptor antagonists such as MK-801 with addictive drugs prevents the development of behavioral sensitization and therefore concluded that NMDA receptor transmission is necessary for sensitization. However, according to “State-dependency” interpretation, NMDA receptor antagonists do not prevent sensitization. Rather, they become a conditioned stimulus for the sensitized response. There is also considerable evidence showing that the circumstances surrounding drug administration play an important role in modulating the development and expression of the sensitization. Thus, we attempted to investigate the interactions of MK-801 and environmental cues on the behavioral sensitization induced by morphine and determine whether the rats that receive MK-801+morphine combination will develop state-dependency to the effect of MK-801.
    42 male Wistar rats were randomly divided into six groups: Saline, MK-801, Morphine (paired group), MK-801 plus Morphine (paired group), Morphine (unpaired group) and MK-801 plus Morphine (unpaired group). During the development period, each rat was administered with MK-801 (0.1mg/kg) or saline by intraperitoneal, 30 minutes later administered with morphine (5mg/kg) or saline for 7 days on end. In the paired group, the administration of morphine was performed with environmental cues (test cage) and the unpaired group received morphine without cues by replacing them into their home cage. The locomotor activities of the rats in paired group were monitored daily immediately after the second injection by using computer-interfaced monitoring system. During the expression period, all the rats were received challenge injection for three times by morphine (day15), MK-801 (day18) and MK-801 plus morphine (day21) each. The distance traveled (cm) during the development period was analyzed by two-way ANOVA with treatment day as the repeated measure. The data from the three challenge tests were separately analyzed by one-way ANOVA. Post hoc analyses (LSD test) were performed for assessing specific group comparison.
    MK-801 did not block but rather enhanced the day-to-day increase in morphine-induced locomotion. When, following initial sensitization, morphine was given in the absence of MK-801, there was no expression of sensitization of the rats in both paired and unpaired groups that have received MK-801 plus morphine during the development period; the sensitized response of animals previously treated with morphine in the MK-801 drug state was expressed only when the animal was tested in the MK-801 drug state.
    The development of behavioral sensitization to morphine is not prevented by MK-801. Rather, the co-administration of MK-801 has made the sensitization of morphine state dependent; the sensitization can be better expressed in the same state under which it developed than under any other state. The interoceptive MK-801 cues has become one of conditioned stimulus, and it overshadows the environmental cues which serve as another conditioned stimulus. These findings illustrate the state-dependent effects of MK-801 may not only restricted to atypical stimulants such as bromocriptine, and the role of NMDA receptor in behavioral sensitization could benefit from further examination with some other NMDA receptor antagonists which are less discriminative
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    Cognitive Development on Recognizing Goal-directed Action of Biological Kinds in 4-to-7-Year-Olds
    Qin Sulan
    2007, 39 (06):  1055-1062. 
    Abstract ( 1784 )  
    Creatures are the living entities, which go for advantages and avoid disadvantages in order to keep themselves living and race breeding, so all creatures have goal-directed action. Goal-directed action is the basic nature for living things, but non-living things have no such nature, so it is an important standard to distinguish living and non-living things, but for 4-to-7-year-old children, the following three questions are uncertain. How or Whether they carry on entity distinguish of living things and non- living things by goal-directed action, or whether the children have formed the naïve biology theory in this dimension, so this study will provide theory and experimental proof for naïve biology theory development in children’s core domain.
    The study has applied structure mode interviewing, by making simulated true situation cartoon story scenarios (three for each of animals, plants, and non-living things, the orders are counterbalanced), subjects are tested individually according to the presenting modes on the computer. Subjects are children from 4 to 7-years-old, among them, children of 4-year-old are 25, children of 5-year-old, children of 6-year-old children of 7-year-old are all 24, 49 boys , 48 girls. The study is 3(animals, plants, man-made things) by 4(age) mixed experiment design, entity stimulants are subject design, age is design among subject.
    Results showed that: (1) For 4-7children, the cognitive development of entity distinguish in goal-directed action dimension embodies four stages from low level to high level: cognitive mode based on teleology (0 level), cognitive mode based on animals(level 1), cognitive mode based on living things (level 2) and the cognitive pattern based on entity distinguish(level 3). (2)For 4-7 children, the consistency of cause and effect cognitive development and entity distinguish development has also experienced the process from vague to polarization and concordance. (3) For children, 5-year-old and 6-year-old is the fast period of goal-directed cognitive development, domain knowledge has obvious simulative effect, but affected by age and domain tasks.
    Under such experimental situation, according to the analysis on goal-directed action cognitive development quality and quantity, we have concluded: The children’s cognitive development doesn’t follow the rule of all or none, while it follows the unity rule of continuous and stage. According to naïve biology theory by Inagaki and “theory” theory by Wellman, and children’s goal-directed action entity distinguish, cause and result cognition and its unity, the study shows that preschoolers form gradually the naïve biology theory in goal-directed action dimension, field knowledge can promote children’s cognition development, what’s more, the result is best in Zone of Proximal Development and key developing period
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    The Influence of Parent-Teen Communication about Sex on Adolescents’ Sexual Attitude and Behavior: Parent-teen Attachment Style as a Moderator
    Wang Zhengyan,Zhao Dongyan,Lie Li
    2007, 39 (06):  1063-1073. 
    Abstract ( 3227 )  
    The influence of parent-teen communication on adolescents’ sexual behavior had been examined in a number of studies. Previous findings have suggested that parent-teen communication is related to lower levels of adolescents’ engagement in sexual risk-taking behavior. Howefer, little is known about this issue in Chinese parents and adolescents. A large portion of Chinese parents (41.65%) thinks that sex education is useless in the family. 33.20% Chinese parents believe that adolescents can teach themselves about sex. Others feel embarrassed when talking about sex with their children. In sum, few studies have examined the role Chinese parents in adolescents’ sexual behavior. Therefore, this study focused on examining how parental communication about sex influences adolescents’ sexual attitude and behavior in China.
    We hypothesized that due to the extreme-privacy nature of sex behaviors in China, little or no communication would take place unless parents and adolescents trusted each other. Past studies have shown that adolescents with a secure attachment style trust their parents more than those with an insecure attachment style. Therefore, parent-child secure and insecure attachment may play a moderating role in the relations between parent-teen communication and adolescents’ sex behavior.
    A sample of adolescents (497 girls, 350 boys) from Beijing, China, aged from 15 to 19 years (mean age 16.36 years) , participated in the study. The self-report measures included 1) Openness of communication, 2) communicational comfort about sexual topics, 3) adolescent sexual behavior and attitude, and 4) parent-child attachment style were administered to the adolescents.
    Two 2 (gender) × 4 (occupations) × 4 (education) multivariate analysis of variance (MANOVA) were run for mother and father respectively to examine the effects of gender of adolescent, parent occupations, and parent’s level of education on communication openness and comfort. Two significant main effects of gender had been revealed. No significant 2 way or 3-way (gender x occupations× education) interactions were found. The following up ANOVAs indicated significant main effects of gender for both father and mother on communication comfort. Boys scored higher on communication comfort than girls, regardless of whether it was mother of farther they communicated with. A further structure equation modeling analysis first revealed that communication openness significantly, and negatively predicted adolescents’ sexual behavior (including kiss, touch, hug and sexual intercourse) and positively predicted adolescents’ negative attitudes about peers’ sexual behaviors. However, communication comfort significantly and negatively predicted adolescents’ disagreement on peers’ sexual behaviors. Second, parents’ attachment moderated the effect of communication openness on adolescent sexuality, specifically, strengthening the negative relation between communication openness and adolescent sexuality.
    Taken together, for adolescents who were insecurely attached with parents, communication openness was more negatively related to their sexual behavior, comparing to those who were securely attached. This may be because openness in communication between parents and adolescents has an inhibiting effect on adolescent’s sexuality in families where adolescents’ attachment with father and mother were both insecure. In other words, in families with an insecure parent-child attachment style (esp. single father/mother family, divorced family, disorganized family and so on), adolescents whose parents communicated more sexual topics with them are more likely to develop patterns of conservative sexual attitudes and reduced sexual behaviors.
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    The Interaction among Deaf Students’ Mental Health, Achievement Motivation and Behavioral Mode
    Tao Xinhua,Zhu Yan,Zhang Pulin
    2007, 39 (06):  1074-1083. 
    Abstract ( 2513 )  
    As a special group, nowadays deaf students obtain more and more attention. Previous research found that their mental health lever was lower than normal students, but little researches were applied to find the reason of that. In the preliminary research, the inner and external factors related to the mental were discussed based in Stress Respond Mechanisms.
    There are 114 deaf students in Suzhou considered as subjects in the research, among which 67 are male and 47 are female. Learning stress, coping style, achievement motivation, social support are considered as antecedents to deaf students’ mental health. Questionnaires and self-administered technique are used in this research. Multiple regression analysis is used to analyze the hypotheses. In order to prove the statistical results, this research carried out an interview which including 8 deaf students and 6 teachers.
    The results are summarized as follows: (1) Whether general questionnaire or three sub-questionnaire of mental health, deaf students’ lever is lower than that of normal students, which is as same as the previous research; (2) The learning stress of deaf students mainly comes from others’ expectation, high learning object set up by their own, heavy learning assignment or competition among classmates; (3) The four coping style of deaf students commonly used are problem-solving, help-seeking and withdrawal. Compared to normal students, deaf students are adapt to adopt fantasy to cope with the frustration and trouble; (4) The social support of deaf students is more than that of normal students; (5) Whether total achievement motivation or external and inner achievement motivation of deaf students is higher than that of normal students, and deaf students’ inner achievement motivation is higher than their external achievement motivation; (6) Deaf students with learning stress, coping style, achievement motivation have predictive power over mental health.
    The present findings shows the influencing Mechanisms of deaf students’ mental health, which can serve as the scientific base for improving deaf students’ mental health. At the same time, the result is useful for the development of Special Education. Owning to the particularity of deaf students, their education should be different from the normal students, especially reinforcing the education of mental health.
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    Impacts of Different Approaches of Emotion Regulation on Memory
    Li Jing,Lu Jiamei
    2007, 39 (06):  1084-1092. 
    Abstract ( 3395 )  
    The research on the relationship between emotion regulation and cognition is a hotly contested issue. There exists 2 major viewpoints whether emotion regulation impacts on cognition. Emotion Regulation Automatic Processing Theory states that the capacity of emotion regulation is inherent and people don’t use their cognition. Therefore, emotion regulation has no impact on people’s cognitive behaviors and their corresponding consequences. The other point is the perspective from Emotion Regulation Cognition Consumption Theory, which states that emotion regulation is self-regulation and that any kind of self-regulation has to consume psychological resources. Therefore, people have to exert their cognition, and the emotion regulation has an impact on people’s cognitive behaviors and their corresponding consequences. In recent years, Gross has contributed major research in this field. He classified emotion regulation into antecedent-focused emotion regulation and response-focused emotion regulation. According to this, different approaches of emotion regulation have different mechanisms which result in different impacts on cognition.
    Memory is one important aspect of cognition. This experimental research design probes how the antecedent-focused emotion regulation and response-focused emotion regulation as well as decreased emotion regulation and increased emotion regulation affect memory . The research used a 2 stage design with experiment probes as it impacts 4 approaches of emotion regulation on memory and assessment memory. The 4 approaches of emotion regulation consist of: antecedent-focused emotion regulation (Reappraisal and rumination) and response-focused emotion regulation(expressive suppression and expressive revealing).The subjects consisted of randomly select SHNU students from several majors. There were 43 males and 78 females. Their mean age was 21.04 and standard deviation was o.96. They were divided into 5 groups, each group adopting one of the approaches. In the first stage of the experiment, the students’ emotions were measured after viewing a war movie clip. Each group viewed the movie clip from the 4 different approaches of emotion regulation. In the second stage, all subjects were required to fill out a questionnaire on self-evaluation of visual and audio memory according to their previous test. The entire process took 30 minutes.
    The results reveal that: (1) Reappraisal and rumination have no significant impact on memory. Expressive suppression and expressive revealing have demonstrated significant impacts on memory due to their suppression affects auditory memory and expressive revealing affects both visual and auditory memory. (2) Reappraisal, rumination and expressive revealing have no impact on metamemory, while expressive suppression has significant impact on metamemory as it affects auditory metamemory. (3) There is neither sex nor student major differences in the impact that different emotion regulation approaches have on memory. However, as to the metamemory, there is no sex but student major differences.
    Based on these results , different emotion regulation approaches have different impacts on memory and metamemory
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    Impact of Public Policy-making Procedures on the Acceptability of A Public Policy
    Li Dazhi Wang Erping
    2007, 39 (06):  1093-1101. 
    Abstract ( 2275 )  
    This research addresses the problems of public policy-making procedures. In conducting our research, we considered public policy as the allocation or reallocation of interests or resources among different members of the public. Due to limited resources, administrations should trade off all interests among different segments of society when formulating a policy. Unfortunately, in recent years there have been several mass conflicts with administration of public policy. This infers that some people’s interests were ignored or harmed by certain policies. According to the theory of procedural justice, people may accept the unexpected result if they consider the procedure is just. This research hypothesizes that there are certain problems in current policy-making procedures and that improving these procedures may make policies more acceptable.
    A pilot study was conducted by interviewing ten scholars from a range of disciplines. The interview record transcripts were coded by three analysts. The results indicate that: 1) Most of the scholars criticized current public policies as lacking sensitivity to public issues; 2) Most of them considered that current public policies do not resolve problems effectively; and 3) They all considered that psychology research may enhance awareness of public issues and improve the effectiveness of policy.
    In study 2, the procedure of public policy was tracked and compared with a social survey. The Beijing government would like to increase the taxi fare rate to cope with the rising price of petroleum. Although the majority of delegates in a hearing of witnesses supported the policy consideration, the social survey of 189 residents and 62 taxi divers indicated that both of them oppose the consideration. The findings indicate that the hearing of witnesses was not able to delegate the opinions of the public, resulting in the policy failing to resolve the problem.
    Study 3 was a nonequivalent control group quasi-experiment. Visitors of two Internet Website were chosen as subjects for original photo games. For the experiment group, visitors were invited to express their desires and suggestions on the game rules for one week, and then declare rules referencing the suggestions before starting the game. Meanwhile, the control group simply declared the rules at the beginning of the game. Compared with the two games during four weeks, the experiment group submitted more photos than the control group.
    The results of this research imply that, the good will of policy makers is not enough to make a policy effective. Surveys on public attitudes at the beginning of the policy-making process can allow policy makers to better determine public issues, assess the tradeoff of public interests, help ensure policies are more acceptable, and help foster a harmonious society. The authors of this research suggest that psychology research should take more social level problems into account in the policy-making process
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    Construct Dimension of the Employee’s Content of Organizational Socialization in China

    Zhao Guoxiang,Wang Minghui,Ling Wenquan

    2007, 39 (06):  1102-1110. 
    Abstract ( 2077 )  
    Organizational socialization is a learning process by which an individual adjusts the attitudes, behaviors he or she needs to participate as an organizational member, and it has become one of the critical issues in the fields of organizational behavior and human resource management.
    The methods used in this study involved literature review, interview, pilot study and survey. Based on the literature review, interview and pilot study, items for Organizational Socialization Content Questionnaire were developed. The survey data was collected from managers and employees of 22 companies which were different kinds and from different districts of China. The survey data was mainly analyzed with correlation analysis, exploratory factor analysis (EFA) and confirmatory factor analysis (CFA).
    The results show that organizational socialization content of Chinese employees is a four-dimension construct, comprising organizational culture, job competency, interpersonal relationship and organizational politics. Organizational Socialization Content Questionnaire has high validity and reliability. That is to say, the four-dimension construct can reflect the contents which Chinese employees should learn in the process of organizational socialization. At the same time, the results are different from those results generated in western countries. The construct, content and nomination of organizational socialization and the differences compared to western studies are discussed.
    Finally, future research orientations are discussed, especially the antecedents and consequences of organizational socialization content should be studied deeply.
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    The Mechanism of How Trust Climate Impacts on Individual Performance
    Li Ning,Yan Jin
    2007, 39 (06):  1111-1121. 
    Abstract ( 1878 )  
    This paper explored the mechanism through which trust climate influences on individual performance. From the scope of psychological dynamics, we investigated the relationship among perception of organizational climate, motivation and individual behaviors to crystallize how a trustworthy organizational environment favors superior individual performance.
    The concept of trust climate is conceptualized as a kind of perception based on subjective assessment for the trustworthiness of entire organizational environment. In order to develop a solid operational definition of trust climate, we built our framework on Costigan’s work (1998). In their theorizing, three salient parties mainly responsible for individuals’ overall trust perception of organizational environment are located as: direct leader, co-workers and top management. For the purpose of both theoretical parsimony and practical feasibility, we employed these three factors as indicators of trust climate. Psychological safety, defined as a kind of feeling able to show and employ one’s self without fear of negative consequences to self-image, status, or career (Kahn, 1990), is considered as an important factor influencing on spontaneous innovative behaviors and knowledge sharing in workplace.
    The primary aim of this paper is to examine the idea that trust climate enhances levels of psychological safety, which has two independent ways to impact on task performance. First, psychological safety diminishes apprehension about the potential negative consequences of innovative or learning behaviors (enhance the possibility of spontaneous innovation), such as failure or exposure of lack in knowledge or expertise. Second, psychological safety keeps employees from distracters (increase the ability to focus), such as organizational politics, which occupy great amount of employee’s time and energy. With more available resource that could be allocated to behaviors benefiting organization productivity, individuals are likely to have better performance. The two paths are hypothesized to be mutually complementary, and each of them accounts for different mechanisms through which trust climate facilitates superior individual performance.
    Data were obtained from 203 full-time employees of three companies in the eastern China. To avoid the effect of common method bias, we collected employee’s psychological states data and their performance information separately (performance data were rated by employee’s direct leader). Considering the susceptibility of trust research to social desirability, we employed Aryee’s sampling procedure (2002) that is regarded as an effective solution to diminish negative outcome of social desirability. The statistical package of LISREL 8.45 was used to examine the hypotheses. The procedure of testing mediator proposed by Baron & Kendy (1980) was followed to scrutinize the relations between variables.
    In the first stage of data analysis, we tested the hypothesis whether psychological safety mediates the relationship between trust climate and individual performance. In order to provide a stringent examination of our hypotheses, two alternative nested models were established and compared with the hypothesized model. It was revealed that effect of trust climate on task performance is mediated by psychological safety. In the second stage of data analysis, we examined the mediating role of spontaneous innovation and ability to focus in the process that psychological safety translates into performance. Following the same logic employed in the first stage, seven nested alternative models were constructed for comparisons. Results supported the mediating effect of spontaneous innovation and ability to focus, and it also indicated the existence of other potential way(s) that psychological safety impacts on performance, beyond the two paths examined in this article. Finally, the theoretical and managerial implications were discussed.
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    A Longitudinal Study on Newcomers’ Pre-entry Expectations

    Yao Qi,Ma Huawei,Li Qiang

    2007, 39 (06):  1122-1130. 
    Abstract ( 2191 )  
    The early stage of organizational socialization is of great importance to both newcomers and organizations. One of the bases for the conception of organizational socialization is pre-entry expectations, which include the following three dimensions: work expectation, team expectation, and firm expectation. To some degree, socialization included the adjustment processes related to newcomers’ pre-entry expectations.
    Nowadays, most researches on pre-entry expectations in socialization focus on the met expectations and examine their effects on some important outcomes of socialization; they are not, however, involved with the transformation processes or the relations among the processes of socialization. This research aimed to explore the transformation process of pre-entry expectations at an early stage of socialization and to understand newcomers’ adjustment rates.
    In the field of I/O psychology, less attention has been paid to the processing of cross-sectional data using descriptive analysis and simple difference test; however, researchers have been increasingly interested in developing the mechanism and process of specific variables. Intraindividual change over time was the essence of the change phenomenon hypothesized to occur in the individual adaptation process. Therefore, this research employed a longitudinal research design and analyzed data using a latent growth curve model (LGM); further, we explored not only the intraindividual changes but also interindividual changes.
    This 4-wave longitudinal study of 419 newcomers examined their pre-entry expectations and corresponding actual perceptions within a span of 6 months with NPEQ and its revisional editions, using an LGM as the analytical tool.
    The results suggested the following. (1) The transformation process of pre-entry expectations at an early stage of socialization was characterized by a unique pattern: work expectation decreased in a linear trajectory, while team and firm expectations, in an unspecified trajectory. After 6 months, only firm expectations tended to be stable. (2) There were significant individual differences in the change rates for all aspects of the pre-entry expectations, while the individual differences in the initial stages existed only in work expectation. (3) There were significant positive correlations among all aspects of the initial stages and change rates of the pre-entry expectations.
    According to this study and previous literature, enterprises should extend their concept of training and manage expectations according to the expectations dynamic patterns. Issues such as the predictors of individual differences need to be studied in detail in the future.
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    Total Contents of Acta Psychologica Sinica 2007 Volum 39
    Editor
    2007, 39 (06):  1131-1139. 
    Abstract ( 1282 )  
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    Thanks all reviewers 2007
    editor
    2007, 39 (06):  1140-1140. 
    Abstract ( 1272 )  
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