title: Speed-dependent motion-sensitive responses in V5: an fMRI study.
abstract: This fMRI study examined motion-sensitive responses in human area V5 as a function of stimulus speed. Consistent with electrophysiological findings, we observed optimal responses at intermediate speeds of around 7 degrees/s to 30 degrees/s. The results are consistent with a nonlinear (inverted "U") dependency on speed that was also observed in V3a. V1 activation was observed to decrease linearly as speed increased. This is consistent with the fact that speed-sensitive cells in V1 have been shown to be tuned to much slower speeds than in V5.
authors.affiliation: Leopold Muller Functional Imaging Laboratory, Wellcome Department of Cognitive Neurology, Institute of Neurology, London, UK. dave@fil.ion.ucl.ac.uk
authors.forename: D
authors.initials: D
authors.lastname: Chawla
authors.forename: J
authors.initials: J
authors.lastname: Phillips
authors.forename: C
authors.initials: C
authors.lastname: Buechel
authors.forename: R
authors.initials: R
authors.lastname: Edwards
authors.forename: K J
authors.initials: KJ
authors.lastname: Friston
mesh_terms: D001921:Brain / Q000502:physiology*; D003463:Cues; D003627:Data Interpretation, Statistical; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009039:Motion Perception / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology*; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*