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81.
Language is often perceived together with visual information. Recent experimental evidences indicated that, during spoken language comprehension, the brain can immediately integrate visual information with semantic or syntactic information from speech. Here we used the mismatch negativity to further investigate whether prosodic information from speech could be immediately integrated into a visual scene context or not, and especially the time course and automaticity of this integration process. Sixteen Chinese native speakers participated in the study. The materials included Chinese spoken sentences and picture pairs. In the audiovisual situation, relative to the concomitant pictures, the spoken sentence was appropriately accented in the standard stimuli, but inappropriately accented in the two kinds of deviant stimuli. In the purely auditory situation, the speech sentences were presented without pictures. It was found that the deviants evoked mismatch responses in both audiovisual and purely auditory situations; the mismatch negativity in the purely auditory situation peaked at the same time as, but was weaker than that evoked by the same deviant speech sounds in the audiovisual situation. This pattern of results suggested immediate integration of prosodic information from speech and visual information from pictures in the absence of focused attention. 相似文献
82.
The effect of an acute bout of moderate treadmill walking on behavioral and neuroelectric indexes of the cognitive control of attention and applied aspects of cognition involved in school-based academic performance were assessed. A within-subjects design included 20 preadolescent participants (age=9.5±0.5 years; eight female) to assess exercise-induced changes in performance during a modified flanker task and the Wide Range Achievement Test 3. The resting session consisted of cognitive testing followed by a cardiorespiratory fitness assessment to determine aerobic fitness. The exercise session consisted of 20 min of walking on a motor-driven treadmill at 60% of estimated maximum heart rate followed by cognitive testing once heart rate returned to within 10% of pre-exercise levels. Results indicated an improvement in response accuracy, larger P3 amplitude, and better performance on the academic achievement test following aerobic exercise relative to the resting session. Collectively, these findings indicate that single, acute bouts of moderately-intense aerobic exercise (i.e. walking) may improve the cognitive control of attention in preadolescent children, and further support the use of moderate acute exercise as a contributing factor for increasing attention and academic performance. These data suggest that single bouts of exercise affect specific underlying processes that support cognitive health and may be necessary for effective functioning across the lifespan. 相似文献
83.
Performance errors are indexed in the brain even if they are not consciously registered, as demonstrated by the error-related negativity (ERN or Ne) event-related potential. It has recently been shown that another response-locked potential, the error positivity (Pe), follows the Ne, but only in those trials in which the participants consciously detect making the error ('Aware Errors'). In the present study we generalize these findings to an auditory task and investigate possible caveats in the interpretation of the Pe as an index of error awareness. In an auditory Go/No-Go error-awareness task (auditory EAT) participants pressed an additional 'fix error' button after noticing that they had made an error. As in visual tasks, the Ne was similar for aware ('fixed') and unaware ('unfixed') errors, while the Pe was enhanced only for Aware Errors. Within subjects, the Ne and Pe behaved in similar fashions for auditory and visual errors. A control condition confirmed that the awareness effect was not due to the requirement to report error awareness. These results reinforce the evidence in favor of the Pe as a correlate of conscious error processing, and imply that this process is not modality-specific. Nevertheless, single-trial analysis suggested that the Pe may be a delayed P3b related to stimulus processing rather than to response monitoring. 相似文献
84.
重复经颅磁刺激对催乳素及事件相关电位P300的影响 总被引:1,自引:0,他引:1
目的:探讨重复经颅磁刺激(rTMS)对男性精神分裂症患者血清催乳素(PRL)水平及事件相关电位P300的影响。方法:将43例男性精神分裂症患者随机分为rTMS组(21例)和对照组(22例)。rTMS组在稳定剂量的利培酮3~6 mg/d治疗的同时给予连续5 d的高频rTMS刺激,对照组采用假rTMS刺激。刺激前后对两组分别进行血清PRL测定、P300检查及阳性和阴性症状量表(PANSS)、17项汉密尔顿抑郁量表(HAMD)评定。结果:刺激前两组PRL水平差异无统计学意义(P>0.05);治疗后,rTMS组PRL水平高于治疗前,差异有统计学意义(P<0.01);与治疗前比较,治疗后在CZ点,rTMS组P300的P2、P3波幅升高(P均<0.01)。而对照组P300各项指标治疗前后变化均无统计学意义(P均>0.05)。与治疗前比较,治疗后rTMS组及对照组PANSS总分及各因子分变化均无统计学意义(P均>0.05)。rTMS组治疗后HAMD评分下降(P<0.05)。结论:高频rTMS可使男性精神分裂症患者P300的P2、P3波幅升高,改善患者的认知功能及抑郁情绪。但同时会使血清PRL水平增高。 相似文献
85.
目的探讨抗抑郁剂对癫痫患者认知功能和情感障碍的影响。方法收集癫痫患者320例,正常对照组56例。320例癫痫患者随机分为百忧解治疗组和常规治疗组(每组160例)。百忧解治疗组在常规抗癫痫治疗的同时加用百忧解抗抑郁治疗,每日20mg,连服12周。各组分别进行韦氏智能测定和情感测定,并应用事件相关电位P300、N400研究,对比分析癫痫患者认知功能和情感障碍的特征。结果320例癫痫患者中,智能水平低于正常者(IQ值≤90分)259例(80.9%),智能水平明显低下者(IQ值≤70分)168例(52.8%);246例(76.9%)伴有抑郁,283例(88.4%)伴有焦虑。联合应用抗癫痫药组认知障碍和情感障碍均较单药服药组严重。伴随着认知功能障碍和情感障碍,癫痫患者P300和N400的潜伏期明显延长、波幅降低。治疗12周后常规治疗组和百忧解治疗组认知功能和情感障碍均有改善,P300和N400潜伏期和波幅亦明显改善,且百忧解治疗组的改善更加明显。结论抗癫痫药可造成癫痫患者认知功能的损害,单药应用较联合用药对癫痫患者认知功能损害轻。伴随着认知功能障碍和情感障碍,癫痫患者P300和N400潜伏期明显延长、波幅降低。抗抑郁治疗可改善癫痫患者的认知功能。 相似文献
86.
87.
Ethnopharmacological relevance
Traditional Chinese medicine (TCM), which is fundamentally different from Western medicine, has been widely investigated using various approaches. Cellular- or molecular-based imaging has been used to investigate and illuminate the various challenges identified and progress made using therapeutic methods in TCM. Insight into the processes of TCM at the cellular and molecular changes and the ability to image these processes will enhance our understanding of various diseases of TCM and will provide new tools to diagnose and treat patients.Materials and methods
Various TCM therapies including herbs and formulations, acupuncture and moxibustion, massage, Gua Sha, and diet therapy have been analyzed using positron emission tomography, single photon emission computed tomography, functional magnetic resonance imaging and ultrasound and optical imaging. These imaging tools have kept pace with developments in molecular biology, nuclear medicine, and computer technology.Results
We provide an overview of recent developments in demystifying ancient knowledge - like the power of energy flow and blood flow meridians, and serial naturopathies - which are essential to visually and vividly recognize the body using modern technology.Conclusions
In TCM, treatment can be individualized in a holistic or systematic view that is consistent with molecular imaging technologies. Future studies might include using molecular imaging in conjunction with TCM to easily diagnose or monitor patients naturally and noninvasively. 相似文献88.
对国内外ERP测谎研究进行了总结和讨论。ERP测谎目前采用的编题方法有准绳问题测试法(CQT)和犯罪知识测试法(GKT);涉及的脑电成分主要为P300;研究中使用的统计指标有波幅、潜伏期、头皮分布等,但头皮分布能否成为一种新的测谎统计指标还没有定论;统计方法早先使用方差分析,但该方法难以进行单个人的鉴别,因此研究者现在多采用Bootstrap等来进行统计。最后,对目前ERP在测谎实践中所面临的困难、解决途径和应用前景等进行了论述。 相似文献
89.
Knoeferle P Habets B Crocker MW Münte TF 《Cerebral cortex (New York, N.Y. : 1991)》2008,18(4):789-795
A central topic in sentence comprehension research is the kinds of information and mechanisms involved in resolving temporary ambiguity regarding the syntactic structure of a sentence. Gaze patterns in scenes during spoken sentence comprehension have provided strong evidence that visual scenes trigger rapid syntactic reanalysis. However, they have also been interpreted as reflecting nonlinguistic, visual processes. Furthermore, little is known as to whether similar processes of syntactic revision are triggered by linguistic versus scene cues. To better understand how scenes influence comprehension and its time course, we recorded event-related potentials (ERPs) during the comprehension of spoken sentences that relate to depicted events. Prior electrophysiological research has observed a P600 when structural disambiguation toward a noncanonical structure occurred during reading and in the absence of scenes. We observed an ERP component with a similar latency, polarity, and distribution when depicted events disambiguated toward a noncanonical structure. The distributional similarities further suggest that scenes are on a par with linguistic contexts in triggering syntactic revision. Our findings confirm the interpretation of previous eye movement studies and highlight the benefits of combining ERP and eye-tracking measures to ascertain the neuronal processes enabled by, and the locus of attention in, visual contexts. 相似文献
90.
Paxton JL Barch DM Racine CA Braver TS 《Cerebral cortex (New York, N.Y. : 1991)》2008,18(5):1010-1028
Cognitive control impairments in healthy older adults may partly reflect disturbances in the ability to actively maintain goal-relevant information, a function that depends on the engagement of lateral prefrontal cortex (PFC). In 2 functional magnetic resonance imaging studies, healthy young and older adults performed versions of a task in which contextual cues provide goal-relevant information used to bias processing of subsequent ambiguous probes. In Study 1, a blocked design and manipulation of the cue-probe delay interval revealed a generalized pattern of enhanced task-related brain activity in older adults but combined with a specific delay-related reduction of activity in lateral PFC regions. In Study 2, a combined blocked/event-related design revealed enhanced sustained (i.e., across-trial) activity but a reduction in transient trial-related activation in lateral PFC among older adults. Further analyses of within-trial activity dynamics indicated that, within these and other lateral PFC regions, older adults showed reduced activation during the cue and delay period but increased activation at the time of the probe, particularly on high-interference trials. These results are consistent with the hypothesis that age-related impairments in goal maintenance abilities cause a compensatory shift in older adults from a proactive (seen in young adults) to a reactive cognitive control strategy. 相似文献