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Stress has profound impacts on physiology, the brain, cognition and behaviour. In response to stress, the brain initiates several neuromodulatory and endocrine systems. This leads to the release of stress-sensitive mediators, including neuromodulators, hormones and neuropeptides, which in turn feed back on the brain and thus alters cognition and behaviour. As the progress of sophisticated cognitive neuroimaging techniques, cognitive neuroscientists have begun to elucidate the psychological and neural mechanisms underlying detrimental and beneficial effects of stress on emotion, cognition and behaviour in the human brain. Stress-related neuromodulations occur at various stages of information processing, from the initial vigilance, attention, executive functions, learning and memory, and emotion. We reviewed recent advances in cognitive neuroscience of stress and proposed a multidimensional model of stress for better understanding how stress-sensitive neuromodulatory and endocrine systems interplay to impact the brain, cognition and behaviour in humans.

Objective: To explore the satisfactory rate in patients with body dysmorphic disorder (BDD) after cosmetic surgery., Methods: We designed a questionnaire to investigate the postoperative satisfactory rate in patients with BDD and without BDD., Results: There was significant difference in postoperative satisfactory rate between patients with BDD and without BDD., Conclusion: The patients with BDD have a lower satisfactory rate, which is even worse after repeated surgery.

Objective: To investigate if switch cost involved in shifting between neutral and emotional stimuli is reflected by ERPs correlates., Method: The subjects were 14 healthy right-handed college students (7 females, 7 males). Garavan's (1998) task paradigm which was important in studying inner attention shifting was used. The subjects were asked to watch a stimulus sequence comprising Schematic line drawings of faces with neutral and emotional expressions, and make counts of them (neutral faces or emotional faces). EEG signals were recorded at 64 sites., Result: 1) Switching between stimuli elicited slow responses, increased N2 amplitudes and reduced P300 amplitudes. 2) A negative component (Nd370) was found when ERP wave during non-switching trials was subtracted from that during switching trials, and it was found obviously at extensive parietal area. 3) Nd370 amplitude during switching from emotional stimuli to neutral ones was smaller than that during switching from neutral stimuli to emotional ones., Conclusion: Nd370 can be taken as an index of switch cost effect.

Objective: Based on the visual experimental paradigm "precue-target", the search range should be affected by different Chinese characters and the dynamic mechanisms of aging in the brain on the visual attention were investigated., Method: 16 young and 16 old subjects participated the experiment. Cue was comprised of three Chinese words "Large", or "Median" or "Small." The letter "T" was designed as the target stimulus. When the cue was the "large", "T" may appear within 3 circles. When the cue was the "median", "T" may appear within either the median and small circles. When the cue was small, the target "T" may appear only within the small circle., Result: The reaction time (RT) of the two groups of subjects became quick with the reduction of the cue size, while amplitudes of the P1 and N1 component of ERPs increased with the decrease of the cue scale. Old subjects showed longer RT than younger subjects did. The posterior P1 was enhanced significantly and the N1 was inhibited obviously in the old group. The P2 was manifested as significantly inhibitory effect not only in the amplitude but also in the abnormal and unstable waveform., Conclusion: The cognitive function of elderly subjects declined in the task of visual spatial attention. We demonstrated for the first time that the P2 was manifested as significantly inhibitory effect, which suggested that the age-related reduction could lead to dysfunction in the anterior scalp to visual spatial attention (voluntary attention).

Objective: To investigate the visual attention mechanisms of brain, the "cue-target" experimental paradigm was adopted, and the attended range was cued by different Chinese characters., Method: Sixteen healthy young participants (8 male and 8 female, 19-24 years old with an average of 21) served as the subjects. The stimulus sequence was "background-cue-target". The background was comprised of three homocentric white circles. Cue was the Chinese character " large", "median" and " small ". There were 8 capital English letters in each circle, which formed three homocentric circles. "T" was designed as the target stimulus. When the cue was large, the target "T" appeared within the three circles. When the cue was medium, "T" appeared within the medium and small circles. When the cue was small, the T maybe appeared only within the small circle., Result: The reaction time became short with the decrease of the cue scale, while P1 and N1 components amplitudes increased., Conclusion: These results not only provided the electrophysiological evidence for the spot light theory, but also indicated that the spot-light effect happened at the early period of the information processing.

Objective: To compare the cortical mechanisms associated with visual spatial attention directed by location cues and Chinese character cues., Method: Eleven healthy adults (mean age=19) with normal vision served as the subjects. In experiment I, the cue was a circle with black solid line. There were three cue sizes: small, medium and large. In experiment II, three black concentric circles were presented as background, their diameters were the same as the three cues used in experiment I. The cue was one of three Chinese characters small, medium or large respectively. The task of the subjects was to discriminate the target's orientation., Result: RT in experiment II was longer with short ISI. The anterosuperior N1 amplitude elicited by the cue in experiment II was larger than that in experiment I. The inferoposterior P1 latency in experiment II was longer than that in experiment I. Comparing the target evoked ERP, the inferoposterior P1 and N1, latency of experiment II was longer than that in experiment I, the inferoposterior P2 amplitude in experiment II was larger than that in experiment I., Conclusion: The processing of Chinese cue takes place at higher level functional brain regions compared to processing of location cue. The later requires more resource in the earlier stage of cue process and less in the subsequent stage of the task.

Objective. To observe features of early component N170 during face recognition. Method. Scalp distribution, amplitude, and latency of N170 was recorded during face recognition tasks in 16 normal subjects. Result. N170 was elicited by the face stimuli in only half of the subjects and the amplitude was modulated by cognitive tasks. Conclusion. N170 reflects not only face structure encoding unit but also direct visual processing unit. Whether N170 reflects the specialty in face recognition needs further study. The latency of N170 showed left hemisphere dominance and the amplitude showed right hemisphere dominance, indicating that it is not pure right hemisphere dominance in face recognition.

Objective. To compare the cortical mechanisms associated with the visual spatial attention directed by fixed location cues. Method. The subjects were 12 healthy right-handed young volunteers. The visual stimuli were presented with the sequence as: background-cue-target. The cue was a black circle varied in three different sizes randomly. The foci of the circles were always at the center of the screen. The task of the subjects was to search the target within the cue circle and discriminate its orientation. Electroencephalogram (EEG) was recorded from 128 scalp sites. Result. The reaction time (RT) to the targets in the same location shortened when the cue size enlarged. The target evoked P1 and N1 components were not affected by the attentive region size, while the amplitudes of the inferoposterior P2 and anterosuperior N2 enlarged when the attentive region size enlarged. Conclusion. 1) The P1 and N1 components under visual attention were related to the spatial location processes mainly. 2) Cue-evoked P2 and N2 components were related to the size of attentive region. 3) The processes of spatial location information were earlier than attentive scale information, which supported the theory that spatial selection is a prerequisite for correct processes of visual object information.