Several investigations have shown that emotional events show superior recall than non-emotional ones. However, the cortical mechanisms underlying the episodic recall of emotional scenes are still poorly understood. Ou...Several investigations have shown that emotional events show superior recall than non-emotional ones. However, the cortical mechanisms underlying the episodic recall of emotional scenes are still poorly understood. Our main aim was to compare the magnitude of the Event-Related brain Potentials (ERP) old-new effect related to emotionally unpleasant, pleasant and neutral photographic images. As expected, correct recognition of all types of images elicited three topographically distinct ERP components sensitive to the classical old-new recognition effect. The results revealed that the behavioral performances were mainly sensitive to arousal, while the ERP old/new effect over posterior regions (300 - 1000 ms) was exclusively affected by unpleasantness. A later component (1000 - 1400 ms) showed an inverted old/ new effect at parietal sites, which was also sensitive to unpleasantness. These results imply that ERP reflecting episodic conscious recollection and post-retrieval monitoring are clearly affected both by valence and arousal.展开更多
ERP dissociations between implicit and explicit memory have been confirmed by a large amount of evidence in theories of human memory. However, similarities between the two forms of memory have scarcely been studied. A...ERP dissociations between implicit and explicit memory have been confirmed by a large amount of evidence in theories of human memory. However, similarities between the two forms of memory have scarcely been studied. A possibility is that while implicit memory and explicit memory have independ- ent components, they might additionally have shared components. To explore this question, an ERP experiment was conducted with a study-to-test paradigm, in which participants performed a "shallow" (color) study task or a "deep" (pleasant) study task, followed by either a lexical decision (implicit) test (Section 1) or a recognition (explicit) test (Section 2). An interference task was performed concurrently with either the encoding or the retrieval phase of the memory task for encoding interference condition or retrieval interference condition. We compared ERP signatures of implicit and explicit memory as a function of depth of processing or interference. Under the action of the same variables, 300―500 ms old/new ERP effects of implicit and explicit memory showed the same trend. These effects maybe all link with a perceptual representational system. 500―700 ms old/new ERP effects of the two memories were dissociated. They may probably reflect voluntary and involuntary recollection respectively. These results suggested that implicit and explicit memories are not completely independent of each other, but have both independent and shared components.展开更多
To examine the neural mechanisms o working memory in children, event-related potentials (ERPs) were recorded from the 12―13 year-old while they performed a delayed match-to-sample task. The ERP results revealed that ...To examine the neural mechanisms o working memory in children, event-related potentials (ERPs) were recorded from the 12―13 year-old while they performed a delayed match-to-sample task. The ERP results revealed that new and studied objects both evoked a late positive ERP componen peaking around 350 ms during the working memory process. New objects evoke a more positive ERP waveform than the studied objects. The scalp distri bution showed that the frontal-central electrode sites were associated with object working memory proc esses. When tracking new or studied targets among visual distracters, ERPs of targets and distracters revealed differential responses as early as 150 ms The visual targets evoked larger and more positive ERP responses than the distracters. The typica old-new effect was observed between ERPs of stud ied and new distracters. However, ERPs of new and studied targets differed at about 250 ms, in which new targets evoked more positive-going and slightly earlier ERP responses. In addition, a P3a componen was found for new targets only, and was absent in ERPs of studied targets at frontal and central sites The present study results reveal the spatial and temporal characteristics of neural mechanisms un derlying working memory in children, some of which are distinct from those in adults.展开更多
Two event-related potential experiments were conducted to investigate the temporal and the spatial distributions of the old/new effects for the item recognition task and the auditory source retrieval task using pictur...Two event-related potential experiments were conducted to investigate the temporal and the spatial distributions of the old/new effects for the item recognition task and the auditory source retrieval task using picture and Chinese character as stimuli respectively. Stimuli were presented on the center of the screen with their names read out either by female or by male voice simultaneously during the study phase and then two tests were performed separately. One test task was to differentiate the old items from the new ones, and the other task was to judge the items read out by a certain voice during the study phase as targets and other ones as non-targets. The results showed that the old/new effect of the auditory source retrieval task was more sustained over time than that of the item recognition task in both experiments, and the spatial distribution of the former effect was wider than that of the latter one. Both experiments recorded reliable old/new effect over the prefrontal cortex during the source retrieval task. However, there existed some differences of the old/new effect for the auditory source retrieval task between picture and Chinese character, and LORETA source analysis indicated that the differ- ences might be rooted in the temporal lobe. These findings demonstrate that the relevancy of the old/new effects between the item recognition task and the auditory source retrieval task supports the dual-process model; the spatial and the temporal distributions of the old/new effect elicited by the auditory source retrieval task are regulated by both the feature of the experimental material and the perceptual attribute of the voice.展开更多
文摘Several investigations have shown that emotional events show superior recall than non-emotional ones. However, the cortical mechanisms underlying the episodic recall of emotional scenes are still poorly understood. Our main aim was to compare the magnitude of the Event-Related brain Potentials (ERP) old-new effect related to emotionally unpleasant, pleasant and neutral photographic images. As expected, correct recognition of all types of images elicited three topographically distinct ERP components sensitive to the classical old-new recognition effect. The results revealed that the behavioral performances were mainly sensitive to arousal, while the ERP old/new effect over posterior regions (300 - 1000 ms) was exclusively affected by unpleasantness. A later component (1000 - 1400 ms) showed an inverted old/ new effect at parietal sites, which was also sensitive to unpleasantness. These results imply that ERP reflecting episodic conscious recollection and post-retrieval monitoring are clearly affected both by valence and arousal.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 30170322 and 30570603)the Chinese Ministry of Education (Grant No. 20040028001)the Beijing Key Laboratory, and PHR (IHLB)
文摘ERP dissociations between implicit and explicit memory have been confirmed by a large amount of evidence in theories of human memory. However, similarities between the two forms of memory have scarcely been studied. A possibility is that while implicit memory and explicit memory have independ- ent components, they might additionally have shared components. To explore this question, an ERP experiment was conducted with a study-to-test paradigm, in which participants performed a "shallow" (color) study task or a "deep" (pleasant) study task, followed by either a lexical decision (implicit) test (Section 1) or a recognition (explicit) test (Section 2). An interference task was performed concurrently with either the encoding or the retrieval phase of the memory task for encoding interference condition or retrieval interference condition. We compared ERP signatures of implicit and explicit memory as a function of depth of processing or interference. Under the action of the same variables, 300―500 ms old/new ERP effects of implicit and explicit memory showed the same trend. These effects maybe all link with a perceptual representational system. 500―700 ms old/new ERP effects of the two memories were dissociated. They may probably reflect voluntary and involuntary recollection respectively. These results suggested that implicit and explicit memories are not completely independent of each other, but have both independent and shared components.
基金This research was conducted in the Beijing Key Laboratory and in conjunction with the Beijing Key Course.This work was supported by the Chinese Ministry of Education(Grant No.20040028001)the National Natural Science Foundation of China(Grant Nos.30170322&30570603)+1 种基金Ministry of Science and Technology grant 95-special-09Jing Yang is supported by National Institutes of Health(Grant No.AG00986).
文摘To examine the neural mechanisms o working memory in children, event-related potentials (ERPs) were recorded from the 12―13 year-old while they performed a delayed match-to-sample task. The ERP results revealed that new and studied objects both evoked a late positive ERP componen peaking around 350 ms during the working memory process. New objects evoke a more positive ERP waveform than the studied objects. The scalp distri bution showed that the frontal-central electrode sites were associated with object working memory proc esses. When tracking new or studied targets among visual distracters, ERPs of targets and distracters revealed differential responses as early as 150 ms The visual targets evoked larger and more positive ERP responses than the distracters. The typica old-new effect was observed between ERPs of stud ied and new distracters. However, ERPs of new and studied targets differed at about 250 ms, in which new targets evoked more positive-going and slightly earlier ERP responses. In addition, a P3a componen was found for new targets only, and was absent in ERPs of studied targets at frontal and central sites The present study results reveal the spatial and temporal characteristics of neural mechanisms un derlying working memory in children, some of which are distinct from those in adults.
基金the National Natural Science Foundation of China (Grant Nos. 30570603, 30570604 and J0630760)the Ph.D. Programs Foundation of Ministry of Education of China (Nos. 20060335034 and 20070335172)+1 种基金 Educational Bureau Foundation by Zhejiang Province of China (No. 20061310)the Postdoctoral Foundation by Zhejiang Province of China and PHR (IHLB)
文摘Two event-related potential experiments were conducted to investigate the temporal and the spatial distributions of the old/new effects for the item recognition task and the auditory source retrieval task using picture and Chinese character as stimuli respectively. Stimuli were presented on the center of the screen with their names read out either by female or by male voice simultaneously during the study phase and then two tests were performed separately. One test task was to differentiate the old items from the new ones, and the other task was to judge the items read out by a certain voice during the study phase as targets and other ones as non-targets. The results showed that the old/new effect of the auditory source retrieval task was more sustained over time than that of the item recognition task in both experiments, and the spatial distribution of the former effect was wider than that of the latter one. Both experiments recorded reliable old/new effect over the prefrontal cortex during the source retrieval task. However, there existed some differences of the old/new effect for the auditory source retrieval task between picture and Chinese character, and LORETA source analysis indicated that the differ- ences might be rooted in the temporal lobe. These findings demonstrate that the relevancy of the old/new effects between the item recognition task and the auditory source retrieval task supports the dual-process model; the spatial and the temporal distributions of the old/new effect elicited by the auditory source retrieval task are regulated by both the feature of the experimental material and the perceptual attribute of the voice.
