排序方式: 共有218条查询结果,搜索用时 8 毫秒
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Wang Z Pan Y Li W Jiang H Chatzimanolis L Chang J Gong Z Liu L 《Learning & memory (Cold Spring Harbor, N.Y.)》2008,15(3):133-142
The role of the foraging (for) gene, which encodes a cyclic guanosine-3',5'-monophosphate (cGMP)-dependent protein kinase (PKG), in food-search behavior in Drosophila has been intensively studied. However, its functions in other complex behaviors have not been well-characterized. Here, we show experimentally in Drosophila that the for gene is required in the operant visual learning paradigm. Visual pattern memory was normal in a natural variant rover (for(R)) but was impaired in another natural variant sitter (for(S)), which has a lower PKG level. Memory defects in for(S) flies could be rescued by either constitutive or adult-limited expression of for in the fan-shaped body. Interestingly, we showed that such rescue also occurred when for was expressed in the ellipsoid body. Additionally, expression of for in the fifth layer of the fan-shaped body restored sufficient memory for the pattern parameter "elevation" but not for "contour orientation," whereas expression of for in the ellipsoid body restored sufficient memory for both parameters. Our study defines a Drosophila model for further understanding the role of cGMP-PKG signaling in associative learning/memory and the neural circuit underlying this for-dependent visual pattern memory. 相似文献
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Liu YF Chen HI Yu L Kuo YM Wu FS Chuang JI Liao PC Jen CJ 《Neurobiology of learning and memory》2008,90(1):81-89
Cognitive functions usually involve various synaptic proteins and neurotrophic factors in the hippocampus. However, whether treadmill exercise can improve learning and memory by upregulating some of these molecules remain unraveled. To address this question, male BALB/c mice were divided into control and exercise groups, the latter group went through 4 weeks of treadmill exercise training. At the end of exercise training period, they were either tested for passive avoidance (PA) performance or sacrificed for quantifying the hippocampal levels of brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB, the BDNF receptor), synaptotagmin (a Ca2+-dependent synaptic vesicle protein), and SNAP-25 (a presynaptic vesicular fusion protein). Our results showed that treadmill exercise training (1) increased the retention latency without affecting the fear acquisition in the PA test, (2) transiently increased the hippocampal BDNF level at 1, 2, and 4 h after the completion of exercise training, and (3) persistently increased the hippocampal protein levels of full-length TrkB, phosphorylated TrkB and synaptotagmin, but not truncated TrkB or SNAP-25. Moreover, the protein expression level of full-length TrkB or synaptotagmin was positively correlated with PA performance in mice. Finally, inhibition of TrkB signaling by K252a abolished the exercise-facilitated PA performance and upregulation of TrkB and synaptotagmin. Taken together, these data suggest that the upregulation of TrkB and synaptotagmin in the hippocampus contributes to the exercise-facilitated aversive memory. 相似文献
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Eye movements of young and older adults during reading 总被引:1,自引:0,他引:1
The eye movements of young and older adults were tracked as they read sentences varying in syntactic complexity. In Experiment 1, cleft object and object relative clause sentences were more difficult to process than cleft subject and subject relative clause sentences; however, older adults made many more regressions, resulting in increased regression path fixation times and total fixation times, than young adults while processing cleft object and object relative clause sentences. In Experiment 2, older adults experienced more difficulty than young adults while reading cleft and relative clause sentences with temporary syntactic ambiguities created by deleting the that complementizers. Regression analyses indicated that readers with smaller working memories need more regressions and longer fixation times to process cleft object and object relative clause sentences. These results suggest that age-associated declines in working memory do affect syntactic processing. 相似文献
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Using Mandarin Chinese, a "tone language" in which the pitch contours of syllables differentiate words, the authors examined the acoustic modifications of infant-directed speech (IDS) at the syllable level to test 2 hypotheses: (a) the overall increase in pitch and intonation contour that occurs in IDS at the phrase level would not distort lexical pitch at the syllable level and (b) IDS provides exaggerates cues to lexical tones. Sixteen Mandarin-speaking mothers were recorded while addressing their infants and addressing an adult. The results indicate that IDS does not distort the acoustic cues that are essential to word meaning at the syllable level; evidence of exaggeration of the acoustic differences in IDS was observed, extending previous findings of phonetic exaggeration to the lexical level. 相似文献
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This article reports a calibration procedure that enables researchers to track movements of the eye while allowing relatively
unrestricted head and/or body movement. The eye—head calibration algorithm calculates fixation point based on eye-position
data acquired by a head-mounted eyetracker and corresponding head-position data acquired by a 3-D motion-tracking system.
In a single experiment, we show that this procedure provides robust eye-position estimates while allowing free head movement.
Although several companies offer ready-made systems for this purpose, there is no literature available that makes it possible
for researchers to explore the details of the calibration procedures used by these systems. By making such details available,
we hope to facilitate the development of cost-effective, nonproprietary eyetracking solutions. 相似文献
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To assess the learning of word form and meaning in an unfamiliar writing system, we carried out primed-naming experiments with learners of Chinese at the end of their first and second terms in a Chinese class at an American university. The subjects were required to name a target Chinese character after a prime character had been presented for 500 msec. There were three priming conditions defined by the relation between the prime and the target: orthographically similar, homophonic, and semantically related. At the end of the first term, there was a significant facilitation for naming speed in the orthographic condition, but not in the homophonic or semantic conditions. However, at the end of the second term, orthographical facilitation disappeared. Instead, naming speed was facilitated by semantically related primes. A threshold-style framework was proposed to illustrate the processing of Chinese orthography, phonology, and semantics by second-language learners. 相似文献
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Li Q Liu XS Zeng QW Xue QS Cao XH Liu J Ren Y Yu BW 《Neurobiology of learning and memory》2011,96(3):492-497
Considerable evidence indicates that the noradrenergic system of the basolateral amygdala (BLA) participates in the consolidation of various types of emotionally arousing memories. We previously reported that administration of an anesthetic-dose of sevoflurane immediately after continuous multiple-trail inhibition avoidance (CMIA) training impaired memory consolidation. This experiment investigated whether posttraining noradrenergic activation of the BLA is sufficient to reverse the memory impairing effect of sevoflurane. Adult male Sprague-Dawley rats received bilateral injections of norepinephrine (NE 0.3, 1.0, or 3.0 μg/0.5 μl) or normal saline (NS 0.5 μl) immediately after training in a CMIA paradigm. Subsequently, the rats were exposed to sevoflurane (2% inspired) or air for 2h. Norepinephrine produced a dose-dependent enhancement of memory consolidation on a 24-h retention test. The highest dose of NE tested (3.0 μg/0.5 μl) blocked sevoflurane-induced impairment of memory consolidation and reversed the inhibitory effect of sevoflurane on activity-regulated cytoskeletal protein (Arc) expression in the hippocampus 2h after training. These findings provide evidence that the mechanism mediating the memory-impairing effect of sevoflurane involves a network interaction between the BLA noradrenergic system and modulation of Arc protein expression in the hippocampus. 相似文献