28th International Congress of Psychology August 8 ... - U-netSURF

Event-related potentials (ERPs) were recorded from a young and an older group to investigate age
effects on the neural correlates of successful episodic retrieval in the absence of the potentially
confounding effects of age-related performance differences. Relative to ERPs elicited by
unstudied pictures, ERPs elicited by items attracting equivalent levels of source accuracy showed
marked age-related differences. Those from younger subjects demonstrated the positive-going,
‘left parietal’ and ‘right frontal’, ‘old/new’ effects. In contrast, analogous ERPs from older subjects
contained a large, left-lateralized negative effect. The findings suggest the engagement of
qualitatively different retrieval strategies in the two groups.
2028.96 The time course of brain activation in two-digit comparison: An ERP study, Hui Zhao,
Qi Dong, Hongchuan Zhang, Yi Guo, Libo Zhao, Beijing Normal University, Beijing, China
Event-related potentials were used to examine the organization of brain activation during two-digit
comparison. ERP recording revealed independent effects of notation and magnitude processing.
Notation processing was reflected by a first negativity at around 150ms after stimulus onset,
which was right lateralized for Arabic digits but bilateral for Chinese. The bilateral activation of
Chinese was different from previous studies with other alphabetic writing. However, magnitude
processing was reflected by the response-locked averaging in both notations which started about
350ms before response. The results strongly supported the assumption that number magnitude is
processed independent of the input modality.
2028.97 An ERP study for the degrees of the difficulty in visual search, Yanyun Ma 1 , Yuejia
Luo 2 , 1 China National Institute for Educational Research, China; 2 Institute of Psychology, Chinese
Academy of Sciences, Beijing, China
The paper mainly probed the relationship between ERP components and the degrees of the
difficulty in visual search. The experiment included four conditions. The initial P1, N1and P2
latencies and amplitudes had no significant differences between different degrees of the difficulty
in visual search. P3 amplitudes increased as the difficulties in visual search decreased. ERP
waveforms of the easiest search condition (parallel processing) were different from that of other
conditions (serial processing). These results might indicate that ERP waveforms of parallel
searches were very different from that of serial search. But all ERP waveforms of serial searches
were very similar.
2028.98 Involvement of NMDA and its receptor NMDAR in central mechanisms underlying
stress-induced behavioral changes, Huanhuan Li, Wenjuan Lin, Institute of Psychology, Chinese
Academy of Sciences, China
The roles of NMDA and NMDAR involving in the mechanisms underlying stress-induced
behavioral changes gained more and more attention. The findings showed that stress upregulate
number or activity of NMDA and NMDAR in some brain regions associated with behaviors, such
as hippocampus and amygdale. Injection of NMDAR antagonists into these regions prior to stress
reduces anxiety and depression, suggesting they were important mediators between stress and
behavior. Furthermore, neurogranin was also a downstream signal molecule involving in
NMDAR-dependant signaling pathway. Studies on neurogranin and behavior may shed new light
on the mechanism studies of relationship between brain and behavior.
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