Document Detail


Visual motion direction is represented in population-level neural response as measured by magnetoencephalography.
MedLine Citation:
PMID:  19285543     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We investigated whether direction information is represented in the population-level neural response evoked by the visual motion stimulus, as measured by magnetoencephalography. Coherent motions with varied speed, varied direction, and different coherence level were presented using random dot kinematography. Peak latency of responses to motion onset was inversely related to speed in all directions, as previously reported, but no significant effect of direction on latency changes was identified. Mutual information entropy (IE) calculated using four-direction response data increased significantly (>2.14) after motion onset in 41.3% of response data and maximum IE was distributed at approximately 20 ms after peak response latency. When response waveforms showing significant differences (by multivariate discriminant analysis) in distribution of the three waveform parameters (peak amplitude, peak latency, and 75% waveform width) with stimulus directions were analyzed, 87 waveform stimulus directions (80.6%) were correctly estimated using these parameters. Correct estimation rate was unaffected by stimulus speed, but was affected by coherence level, even though both speed and coherence affected response amplitude similarly. Our results indicate that speed and direction of stimulus motion are represented in the distinct properties of a response waveform, suggesting that the human brain processes speed and direction separately, at least in part.
Authors:
Y Kaneoke; T Urakawa; R Kakigi
Related Documents :
7308353 - Spatial arrangements of responses by cells in the cat visual cortex to light and dark b...
12480073 - Global speed processing: evidence for local averaging within, but not across two speed ...
18319573 - Functional disorder of the retina in manganese-deficient japanese quail revealed by ele...
Publication Detail:
Type:  Journal Article     Date:  2009-03-12
Journal Detail:
Title:  Neuroscience     Volume:  160     ISSN:  1873-7544     ISO Abbreviation:  Neuroscience     Publication Date:  2009 May 
Date Detail:
Created Date:  2009-04-20     Completed Date:  2009-08-19     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  7605074     Medline TA:  Neuroscience     Country:  United States    
Other Details:
Languages:  eng     Pagination:  676-87     Citation Subset:  IM    
Affiliation:
Department of Integrative Physiology, National Institute for Physiological Sciences, Myodaiji-cho, Okazaki, Japan. kaneyo@nips.ac.jp
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Analysis of Variance
Brain / physiology*
Evoked Potentials, Visual
Eye Movement Measurements
Female
Humans
Magnetoencephalography
Male
Middle Aged
Motion Perception / physiology*
Neurons / physiology*
Photic Stimulation
Reaction Time

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Single administration of 1-benzyl-1,2,3,4-tetrahydroisoquinoline increases the extracellular concent...
Next Document:  Characterization and mapping of sleep-waking specific neurons in the basal forebrain and preoptic hy...