Abstract:
:We studied visual perception using an annular random-dot motion stimulus called the racetrack. We recorded neural activity using magnetoencephalography while subjects viewed variants of this stimulus that contained no inherent motion or various degrees of embedded motion. Subjects reported seeing rotary motion during viewing of all stimuli. We found that, in the absence of any motion signals, patterns of brain activity differed between states of motion perception and nonperception. Furthermore, when subjects perceived motion, activity states within the brain did not differ across stimuli of different amounts of embedded motion. In contrast, we found that during periods of nonperception brain-activity states varied with the amount of motion signal embedded in the stimulus. Taken together, these results suggest that during perception the brain may lock into a stable state in which lower-level signals are suppressed.
journal_name
Proc Natl Acad Sci U S Aauthors
Crowe DA,Leuthold AC,Georgopoulos APdoi
10.1073/pnas.1009857108subject
Has Abstractpub_date
2010-12-28 00:00:00pages
22677-81issue
52eissn
0027-8424issn
1091-6490pii
1009857108journal_volume
107pub_type
杂志文章,随机对照试验abstract::Diffuse celestial sources of relatively low surface brightness such as the Milky Way, zodiacal light, and gegenschein (or contre lumière) can be studied most reliably from above the earth's atmosphere with equipment flown in artificial satellites. We review the techniques used and some of the difficulties encountered ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::The aspartate receptor involved in chemotaxis is modified by methyl esterification at four distinct glutamate residues during the adaptive response of this receptor. To explain the high degree of specificity of this modification, it has been proposed that the methyltransferase recognizes the sequence Glu-Glu-Xaa-Xaa-A...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2013-05-28 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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abstract::Somatic crossing over in flies heterozygous for a dominant Minute mutant may result in two cells, homozygous for wild type and Minute, respectively. If both cells took part in development, a twin spot of two genotypes, different from the rest of the body, would result. Two-hundred wild type spots were found, none of w...
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1980-04-01 00:00:00