The results of visual event-related potential(ERP)examinations and reactiontime(RT)tests were reported in 30 elders and compared with their performanceintellegence quotient(PIQ)scores.The subjects consisted of 18 male...The results of visual event-related potential(ERP)examinations and reactiontime(RT)tests were reported in 30 elders and compared with their performanceintellegence quotient(PIQ)scores.The subjects consisted of 18 males and 12 femalesaged 50-71(mean 61.4)years old.No history of central nervous system disease wasfound.The visual stimuli were randomly presented to the subject,including three sym-bols:E as target stimulus with 0.15 probability,and H and E as nontarget stimuliwith 0.15 and 0.70 probability respectively.The recording electrodes were placed on Fzand Pz.The duration from the subject seeing the target to touching a button immediatelywas considered as reaction time(RT).It was shown that the P3 latency at Pz was longer than that at Fz and the P3amplitude at Pz was larger than that at Fz,and that the RT was longer than P3 latencywith obvious effect of distribution(P【0.05 at Fz and P】0.05 at Pz)as well .The higherthe PIQ scores,the longer the RT and the P3 latency.It is suggested that the ERPmight reflect the differences of PIQ scores,and the P3 is an objective index.We considerthat the research of ERP is of great interest in the neuropsychological and neurological sci-ences.展开更多
This study explored the possibility of using event-related potentials （ERP） for the measurement of picture-recognition memory and examined its correlation with the Chinese Wechsler Memory Scale-revised （WMS-RC） in...This study explored the possibility of using event-related potentials （ERP） for the measurement of picture-recognition memory and examined its correlation with the Chinese Wechsler Memory Scale-revised （WMS-RC） in patients with memory disorder caused by severe traumatic brain injury （sTBI）. The subjects included 20 sTBI patients with memory disorder and 22 healthy individuals. Memory function was measured by using WMS-RC. Behavioral and ERP responses were recorded on-line during performance on a battery of picture recognition and the responses were analyzed off-line for recognition memory effects. Mean memory quotient （MQ） of patients with sTBI was significantly lower than that of the control group. Mean reaction time （RT） was significantly longer and the mean correctness rate （CR） of picture recognition was significantly lower in sTBI group than that of the controls. In controls, the main components of average ERP of picture recognition includes two positive-going waves, designated as P170 and P500, that appear 170 ms and 500 ms after stimulation when the subject could later successfully recall and recognize the pictures. P500 amplitude of target stimulus was significantly higher than that of non-target stimulus. Compared to controls, P500 responses of sTBI group were significantly delayed in latency （P〈0.001） and lower in amplitude （P〈0.001）. P500 latency showed significant negative correlation with MQ and the scores of ＂addition＂, ＂visual recognition＂, ＂picture recall＂, ＂visual reproduction＂ and ＂tactile memory＂ in WMS-RC. ERP of picture recognition provides a neurophysiological approach to directly assess memory impairment, and P500 may serve as a helpful index for memory disorder caused by sTBI in forensic practice.展开更多
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
The P300, an endogenous subcomponent of the event-related potential, is thought to reflect cognitive processes. The event-related potential evoked by the old-new memory recognition task in the oddball paradigm is suit...The P300, an endogenous subcomponent of the event-related potential, is thought to reflect cognitive processes. The event-related potential evoked by the old-new memory recognition task in the oddball paradigm is suitable for examining the neural processes involved in malingered neurocognitive deficits. Forty-four undergraduates were randomly assigned to a simulated malingering group and a truth-telling group, Another 22 patients with head injudes were enrolled as a control group. All participants completed the old-new memory recognition task in the oddball paradigm. The mean P300 amplitude of the simulated malingering group was significantly reduced compared with the truth-telling group （P 〈 0.01）, but was increased compared with the control group （P〈 0.01）. These results revealed that the P300, evoked by the old-new memory recognition task of the oddball paradigm, may be a helpful indicator for determining cognitive malingering.展开更多
Rehabilitation of episodic memory declines typically focuses on alleviating the demand for recall and improving the retrieval process. Modulating the encoding is not commonly practiced, but may nevertheless be importa...Rehabilitation of episodic memory declines typically focuses on alleviating the demand for recall and improving the retrieval process. Modulating the encoding is not commonly practiced, but may nevertheless be important. Seventeen event-related potential (ERP) studies interpreted using the subsequent memory effect, an index of successful encoding, are reviewed and the factors involved in encoding are discussed. The nature of the materials used for testing, modes of encoding, and the nature of the retrieval task are highlighted as important factors. Meaningful materials and processing information semantically enhance encoding to episodic memory. The stud-ies reviewed reveal that older persons process information more uniformly without elaboration compared with their younger counterparts. Although people with mild cognitive impairment have encoding and retrieval deficits, an elaborative type of encoding training that draws on successful encoding factors may help to improve memory performance.展开更多
Recent evidence demonstrates that with training, one can enhance visual working memory (VWM) capacity and attention over time in the near transfer tasks. Not only do these studies reveal the characteristics of VWM loa...Recent evidence demonstrates that with training, one can enhance visual working memory (VWM) capacity and attention over time in the near transfer tasks. Not only do these studies reveal the characteristics of VWM load and the influences of training, they may also provide insights into developing effective rehabilitation for patients with VWM deficiencies. However, few studies have investigated VWM over extended periods of time and evaluated transfer benefits on non-trained tasks. Here, we combined behavioral and electroencephalographical approaches to investigate VWM load, training gains, and transfer benefits. Our results reveal that VWM capacity is directly correlated to the difference of event-related potential waveforms. In particular, the “magic number 4” can be observed through the contralateral delay amplitude and the average capacity is 3.25-item over 15 participants. Furthermore, our findings indicate that VWM capacity can be improved through training;and after training exercises, participants from the training group are able to dramatically improve their performance. Likewise, the training effects on non-trained tasks can also be observed at the 12th week after training. Therefore, we conclude that participants can benefit from training gains, and augmented VWM capacity sustained over long periods of time on specific variety of tasks.展开更多
Mismatch negativity is generated automatically, and is an early monitoring indicator of neuronal integrity impairment and functional abnormality in patients with brain injury, leading to decline of cognitive function....Mismatch negativity is generated automatically, and is an early monitoring indicator of neuronal integrity impairment and functional abnormality in patients with brain injury, leading to decline of cognitive function. Antipsychotic medication cannot affect mismatch negativity. The present study aimed to explore the relationships of mismatch negativity with neurocognition, daily life and social functional outcomes in patients after brain injury. Twelve patients with traumatic brain injury and 12 healthy controls were recruited in this study. We examined neurocogni-tion with the Wechsler Adult Intelligence Scale-Revised China, and daily and social functional outcomes with the Activity of Daily Living Scale and Social Disability Screening Schedule, re-spectively. Mismatch negativity was analyzed from electroencephalogram recording. The results showed that mismatch negativity amplitudes decreased in patients with traumatic brain injury compared with healthy controls. Mismatch negativity amplitude was negatively correlated with measurements of neurocognition and positively correlated with functional outcomes in patients after traumatic brain injury. Further, the most signiifcant positive correlations were found be-tween mismatch negativity in the fronto-central region and measures of functional outcomes. The most signiifcant positive correlations were also found between mismatch negativity at the FCz electrode and daily living function. Mismatch negativity amplitudes were extremely positive-ly associated with Social Disability Screening Schedule scores at the Fz electrode in brain injury patients. These experimental ifndings suggest that mismatch negativity might efifciently relfect functional outcomes in patients after traumatic brain injury.展开更多
The influence of attention on memorizing related items and on available long-term memory (ALTM) was explored,showing that N400 of no-memory items was more negative than that of the memory item.The results of the categ...The influence of attention on memorizing related items and on available long-term memory (ALTM) was explored,showing that N400 of no-memory items was more negative than that of the memory item.The results of the category comparison task indicated that information processing under attention-driven in WM determined the availability of related long-term memory,i.e.,specific content,which was formerly concerned or ignored,yielding different indirect semantic priming effects.These indicate that the orientation of conceptual attention leads the related representations of LTM to diverse activation patterns,supporting the activation-based model.展开更多
Prospective memory (PM) refers to memory for future intentions.Difference due to memory (Dm effect) is the difference in neural activity related to stimuli that were subsequently remembered or forgotten.Using event-re...Prospective memory (PM) refers to memory for future intentions.Difference due to memory (Dm effect) is the difference in neural activity related to stimuli that were subsequently remembered or forgotten.Using event-related potentials (ERPs),the present study investigated the Dm effect for PM using a subsequent task-switching paradigm.The results showed that a Dm effect of ERP P150 was more positive-going for later PM hit trials than for later PM forgotten trials during 100–200 ms.This Dm effect may reflect the process for the production of future intention or the process for attention.Consistent with previously reported Dm effects of other types of memory,we found that the fbN2 (250–280 ms) and late positivity component (400–700 ms) were stronger in later PM hit trials than in forgotten trials.The fbN2 was evoked by Chinese characters.The late positivity component was related to the precise encoding process.In conclusion,because of the early P150,PM encoding appears to be somewhat different from previously identified Dm effects.However,further research is needed.Our findings reveal that Dm effects of PM share similar characteristics with known Dm effects of other types of episodic memory after the very early stage of neural processing.展开更多
Background: Although growing evidence links beta-amyloid (Aβ) and neuronal hyperexcitability in preclinical mouse models of Alzheimer’s disease (AD), a similar association in humans is yet to be established. The fir...Background: Although growing evidence links beta-amyloid (Aβ) and neuronal hyperexcitability in preclinical mouse models of Alzheimer’s disease (AD), a similar association in humans is yet to be established. The first aim of the study was to determine the association between elevated Aβ (Aβ+) and cognitive processes measured by the P3 event-related potential (ERP) in cognitively normal (CN) older adults. The second aim was to compare the event- related power between CNAβ+ and CNAβ−. Methods: Seventeen CNAβ+ participants (age: 73 ± 5, 11 females, Montreal Cognitive Assessment [MoCA] score 26 ± 2) and 17 CNAβ- participants group-matched for age, sex, and MOCA completed a working memory task (n-back with n = 0, 1, 2) test while wearing a 256-channel electro-encephalography net. P3 peak amplitude and latency of the target, nontarget and task difference effect (nontarget−target), and event-related power in the delta, theta, alpha, and beta bands, extracted from Fz, Cz, and Pz, were compared between groups using linear mixed models. P3 ampli-tude of the task difference effect at Fz and event-related power in the delta band were considered main outcomes. Correlations of mean Aβ standard uptake value ratios (SUVR) using positron emission tomography with P3 amplitude and latency of the task difference effect were analyzed using Pearson Correlation Coefficient r. Results: The P3 peak amplitude of the task difference effect at Fz was lower in the CNAβ+ group (P = 0.048). Simi-larly, power was lower in the delta band for nontargets at Fz in the CNAβ+ participants (P = 0.04). The CNAβ+ partici-pants also demonstrated higher theta and alpha power in channels at Cz and Pz, but no changes in P3 ERP. Strong correlations were found between the mean Aβ SUVR and the latency of the 1-back (r = − 0.69;P = 0.003) and 2-back (r = − 0.69;P = 0.004) of the task difference effect at channel Fz in the CNAβ+ group. Conclusions: Our data suggest that the elevated amyloid in cognitively normal older adults is associated with neuronal hyperexcitability. The decreased P3 task difference likely reflects early impairments in working memory processes. Further research is warranted to determine the validity of ERP in predicting clinical, neurobiological, and functional manifestations of AD.展开更多
文摘The results of visual event-related potential(ERP)examinations and reactiontime(RT)tests were reported in 30 elders and compared with their performanceintellegence quotient(PIQ)scores.The subjects consisted of 18 males and 12 femalesaged 50-71(mean 61.4)years old.No history of central nervous system disease wasfound.The visual stimuli were randomly presented to the subject,including three sym-bols:E as target stimulus with 0.15 probability,and H and E as nontarget stimuliwith 0.15 and 0.70 probability respectively.The recording electrodes were placed on Fzand Pz.The duration from the subject seeing the target to touching a button immediatelywas considered as reaction time(RT).It was shown that the P3 latency at Pz was longer than that at Fz and the P3amplitude at Pz was larger than that at Fz,and that the RT was longer than P3 latencywith obvious effect of distribution(P【0.05 at Fz and P】0.05 at Pz)as well .The higherthe PIQ scores,the longer the RT and the P3 latency.It is suggested that the ERPmight reflect the differences of PIQ scores,and the P3 is an objective index.We considerthat the research of ERP is of great interest in the neuropsychological and neurological sci-ences.
文摘This study explored the possibility of using event-related potentials （ERP） for the measurement of picture-recognition memory and examined its correlation with the Chinese Wechsler Memory Scale-revised （WMS-RC） in patients with memory disorder caused by severe traumatic brain injury （sTBI）. The subjects included 20 sTBI patients with memory disorder and 22 healthy individuals. Memory function was measured by using WMS-RC. Behavioral and ERP responses were recorded on-line during performance on a battery of picture recognition and the responses were analyzed off-line for recognition memory effects. Mean memory quotient （MQ） of patients with sTBI was significantly lower than that of the control group. Mean reaction time （RT） was significantly longer and the mean correctness rate （CR） of picture recognition was significantly lower in sTBI group than that of the controls. In controls, the main components of average ERP of picture recognition includes two positive-going waves, designated as P170 and P500, that appear 170 ms and 500 ms after stimulation when the subject could later successfully recall and recognize the pictures. P500 amplitude of target stimulus was significantly higher than that of non-target stimulus. Compared to controls, P500 responses of sTBI group were significantly delayed in latency （P〈0.001） and lower in amplitude （P〈0.001）. P500 latency showed significant negative correlation with MQ and the scores of ＂addition＂, ＂visual recognition＂, ＂picture recall＂, ＂visual reproduction＂ and ＂tactile memory＂ in WMS-RC. ERP of picture recognition provides a neurophysiological approach to directly assess memory impairment, and P500 may serve as a helpful index for memory disorder caused by sTBI in forensic practice.
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.
文摘The P300, an endogenous subcomponent of the event-related potential, is thought to reflect cognitive processes. The event-related potential evoked by the old-new memory recognition task in the oddball paradigm is suitable for examining the neural processes involved in malingered neurocognitive deficits. Forty-four undergraduates were randomly assigned to a simulated malingering group and a truth-telling group, Another 22 patients with head injudes were enrolled as a control group. All participants completed the old-new memory recognition task in the oddball paradigm. The mean P300 amplitude of the simulated malingering group was significantly reduced compared with the truth-telling group （P 〈 0.01）, but was increased compared with the control group （P〈 0.01）. These results revealed that the P300, evoked by the old-new memory recognition task of the oddball paradigm, may be a helpful indicator for determining cognitive malingering.
文摘Rehabilitation of episodic memory declines typically focuses on alleviating the demand for recall and improving the retrieval process. Modulating the encoding is not commonly practiced, but may nevertheless be important. Seventeen event-related potential (ERP) studies interpreted using the subsequent memory effect, an index of successful encoding, are reviewed and the factors involved in encoding are discussed. The nature of the materials used for testing, modes of encoding, and the nature of the retrieval task are highlighted as important factors. Meaningful materials and processing information semantically enhance encoding to episodic memory. The stud-ies reviewed reveal that older persons process information more uniformly without elaboration compared with their younger counterparts. Although people with mild cognitive impairment have encoding and retrieval deficits, an elaborative type of encoding training that draws on successful encoding factors may help to improve memory performance.
文摘Recent evidence demonstrates that with training, one can enhance visual working memory (VWM) capacity and attention over time in the near transfer tasks. Not only do these studies reveal the characteristics of VWM load and the influences of training, they may also provide insights into developing effective rehabilitation for patients with VWM deficiencies. However, few studies have investigated VWM over extended periods of time and evaluated transfer benefits on non-trained tasks. Here, we combined behavioral and electroencephalographical approaches to investigate VWM load, training gains, and transfer benefits. Our results reveal that VWM capacity is directly correlated to the difference of event-related potential waveforms. In particular, the “magic number 4” can be observed through the contralateral delay amplitude and the average capacity is 3.25-item over 15 participants. Furthermore, our findings indicate that VWM capacity can be improved through training;and after training exercises, participants from the training group are able to dramatically improve their performance. Likewise, the training effects on non-trained tasks can also be observed at the 12th week after training. Therefore, we conclude that participants can benefit from training gains, and augmented VWM capacity sustained over long periods of time on specific variety of tasks.
基金supported by grants from the National Natural Science Foundation of China,No.81172911,81373251the National High Technology Research and Development Program of China(863 Program),No.2015AA020503+1 种基金the Science and Technology Development Project of Suzhou of China,No.SZP201304Priority Academic Program Development of Jiangsu Higher Education Institutes of China
文摘Mismatch negativity is generated automatically, and is an early monitoring indicator of neuronal integrity impairment and functional abnormality in patients with brain injury, leading to decline of cognitive function. Antipsychotic medication cannot affect mismatch negativity. The present study aimed to explore the relationships of mismatch negativity with neurocognition, daily life and social functional outcomes in patients after brain injury. Twelve patients with traumatic brain injury and 12 healthy controls were recruited in this study. We examined neurocogni-tion with the Wechsler Adult Intelligence Scale-Revised China, and daily and social functional outcomes with the Activity of Daily Living Scale and Social Disability Screening Schedule, re-spectively. Mismatch negativity was analyzed from electroencephalogram recording. The results showed that mismatch negativity amplitudes decreased in patients with traumatic brain injury compared with healthy controls. Mismatch negativity amplitude was negatively correlated with measurements of neurocognition and positively correlated with functional outcomes in patients after traumatic brain injury. Further, the most signiifcant positive correlations were found be-tween mismatch negativity in the fronto-central region and measures of functional outcomes. The most signiifcant positive correlations were also found between mismatch negativity at the FCz electrode and daily living function. Mismatch negativity amplitudes were extremely positive-ly associated with Social Disability Screening Schedule scores at the Fz electrode in brain injury patients. These experimental ifndings suggest that mismatch negativity might efifciently relfect functional outcomes in patients after traumatic brain injury.
基金supported by the National Natural Science Foundation of China (Grant No. 30870760)the Key Foundation of Beijing Municipal Commission of Education (Grant No. KZ201010028029)supported by the Research Found for Young Scholars of the School of Sociology,China University of Political Science and Law
文摘The influence of attention on memorizing related items and on available long-term memory (ALTM) was explored,showing that N400 of no-memory items was more negative than that of the memory item.The results of the category comparison task indicated that information processing under attention-driven in WM determined the availability of related long-term memory,i.e.,specific content,which was formerly concerned or ignored,yielding different indirect semantic priming effects.These indicate that the orientation of conceptual attention leads the related representations of LTM to diverse activation patterns,supporting the activation-based model.
基金supported by the National Natural Science Foundation of China (Grant No. 30870760)Ministry of Education of China (Grant No. 20101108110004)the Key Foundation of Beijing Municipal Commission of Education (Grant No. KZ201010028029)
文摘Prospective memory (PM) refers to memory for future intentions.Difference due to memory (Dm effect) is the difference in neural activity related to stimuli that were subsequently remembered or forgotten.Using event-related potentials (ERPs),the present study investigated the Dm effect for PM using a subsequent task-switching paradigm.The results showed that a Dm effect of ERP P150 was more positive-going for later PM hit trials than for later PM forgotten trials during 100–200 ms.This Dm effect may reflect the process for the production of future intention or the process for attention.Consistent with previously reported Dm effects of other types of memory,we found that the fbN2 (250–280 ms) and late positivity component (400–700 ms) were stronger in later PM hit trials than in forgotten trials.The fbN2 was evoked by Chinese characters.The late positivity component was related to the precise encoding process.In conclusion,because of the early P150,PM encoding appears to be somewhat different from previously identified Dm effects.However,further research is needed.Our findings reveal that Dm effects of PM share similar characteristics with known Dm effects of other types of episodic memory after the very early stage of neural processing.
基金the National Institute on Aging of the National Institutes of Health under Award Number K01 AG058785This study was supported in part by a pilot grant of the KU Alzheimer Disease Center(P30 AG035982).
文摘Background: Although growing evidence links beta-amyloid (Aβ) and neuronal hyperexcitability in preclinical mouse models of Alzheimer’s disease (AD), a similar association in humans is yet to be established. The first aim of the study was to determine the association between elevated Aβ (Aβ+) and cognitive processes measured by the P3 event-related potential (ERP) in cognitively normal (CN) older adults. The second aim was to compare the event- related power between CNAβ+ and CNAβ−. Methods: Seventeen CNAβ+ participants (age: 73 ± 5, 11 females, Montreal Cognitive Assessment [MoCA] score 26 ± 2) and 17 CNAβ- participants group-matched for age, sex, and MOCA completed a working memory task (n-back with n = 0, 1, 2) test while wearing a 256-channel electro-encephalography net. P3 peak amplitude and latency of the target, nontarget and task difference effect (nontarget−target), and event-related power in the delta, theta, alpha, and beta bands, extracted from Fz, Cz, and Pz, were compared between groups using linear mixed models. P3 ampli-tude of the task difference effect at Fz and event-related power in the delta band were considered main outcomes. Correlations of mean Aβ standard uptake value ratios (SUVR) using positron emission tomography with P3 amplitude and latency of the task difference effect were analyzed using Pearson Correlation Coefficient r. Results: The P3 peak amplitude of the task difference effect at Fz was lower in the CNAβ+ group (P = 0.048). Simi-larly, power was lower in the delta band for nontargets at Fz in the CNAβ+ participants (P = 0.04). The CNAβ+ partici-pants also demonstrated higher theta and alpha power in channels at Cz and Pz, but no changes in P3 ERP. Strong correlations were found between the mean Aβ SUVR and the latency of the 1-back (r = − 0.69;P = 0.003) and 2-back (r = − 0.69;P = 0.004) of the task difference effect at channel Fz in the CNAβ+ group. Conclusions: Our data suggest that the elevated amyloid in cognitively normal older adults is associated with neuronal hyperexcitability. The decreased P3 task difference likely reflects early impairments in working memory processes. Further research is warranted to determine the validity of ERP in predicting clinical, neurobiological, and functional manifestations of AD.
