The perception of a visual """"""""figure"""""""" often relies upon the overall spatial arrangement of its local elements, as demonstrated by the perception of occluded or illusory contours. The global attributes of a visual stimulus can affect the response of visual cortical neurons to the local attributes of the stimulus. For example, the response of neurons in cortical areas V1 and V2 to stimuli within their classical receptive field (cRF) can be modulated by contextual stimuli outside their cRF (in their """"""""surround""""""""). Similarly, V1 and V2 neurons respond to illusory contours (ICs) within their cRF. Neuronal cRFs and local interactions cannot account for these perceptual and neurophysiological phenomena; rather, fast interactions across distant visual field locations are needed to mediate perceptual completion. The long-term goal of this proposal is to disentangle the relative contributions of long-range inter-areal (feedforward and feedback) and intra-areal (horizontal) corticocortical connections to these global-to-local computations in early visual cortex. The neural circuitry and mechanisms involved are likely to be the cornerstone of contour integration, and figure-ground segregation. Thus, results from these studies ultimately will help understanding the neural substrates for higher visual cortical processing and perception in primate and man. ? As a first step towards the broader goal, the work described in this application is designed to investigate how the spatial extent and organization of intra-areal (Aim 1) and inter-areal, feedforward and feedback (Aims 2 and 3), connections relates to the spatial scale and organization of single V1 and V2 neurons' RF, modulatory surround field and response to ICs. The rationale is that the spatial scale of a given connectional system must be commensurate with the spatial scale of the specific neuronal response that it underlies in retinotopically-organized early visual cortex. We will map the total field of connections labeled by small tracer injected cortical points, and overlay these anatomical maps to physiologically recorded retinotopic maps from the same regions of cortex. The visuotopic scale of the connectional fields will then be related to the spatial dimensions of receptive field and modulatory surround field, and with the limits of neuronal responses to ICs, measured physiologically at the injected cortical points ? ?

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
3R01EY015262-01A1S1
Application #
6952935
Study Section
Central Visual Processing Study Section (CVP)
Program Officer
Oberdorfer, Michael
Project Start
2004-08-01
Project End
2009-05-31
Budget Start
2004-08-01
Budget End
2005-05-31
Support Year
1
Fiscal Year
2004
Total Cost
$57,802
Indirect Cost
Name
University of Utah
Department
Ophthalmology
Type
Schools of Medicine
DUNS #
009095365
City
Salt Lake City
State
UT
Country
United States
Zip Code
84112
Kingdom, Frederick A A; Angelucci, Alessandra; Clifford, Colin W G (2014) Special issue: The function of contextual modulation. Vision Res 104:1-2
Nurminen, Lauri; Angelucci, Alessandra (2014) Multiple components of surround modulation in primary visual cortex: multiple neural circuits with multiple functions? Vision Res 104:47-56
Jeffs, Janelle; Federer, Frederick; Ichida, Jennifer M et al. (2013) High-resolution mapping of anatomical connections in marmoset extrastriate cortex reveals a complete representation of the visual field bordering dorsal V2. Cereb Cortex 23:1126-47
Shushruth, S; Nurminen, Lauri; Bijanzadeh, Maryam et al. (2013) Different orientation tuning of near- and far-surround suppression in macaque primary visual cortex mirrors their tuning in human perception. J Neurosci 33:106-19
Shushruth, S; Mangapathy, Pradeep; Ichida, Jennifer M et al. (2012) Strong recurrent networks compute the orientation tuning of surround modulation in the primate primary visual cortex. J Neurosci 32:308-21
Schwabe, Lars; Ichida, Jennifer M; Shushruth, S et al. (2010) Contrast-dependence of surround suppression in Macaque V1: experimental testing of a recurrent network model. Neuroimage 52:777-92
Federer, Frederick; Ichida, Jennifer M; Jeffs, Janelle et al. (2009) Four projection streams from primate V1 to the cytochrome oxidase stripes of V2. J Neurosci 29:15455-71
Jeffs, Janelle; Ichida, Jennifer M; Federer, Frederick et al. (2009) Anatomical evidence for classical and extra-classical receptive field completion across the discontinuous horizontal meridian representation of primate area V2. Cereb Cortex 19:963-81
Shushruth, S; Ichida, Jennifer M; Levitt, Jonathan B et al. (2009) Comparison of spatial summation properties of neurons in macaque V1 and V2. J Neurophysiol 102:2069-83
Ichida, Jennifer M; Schwabe, Lars; Bressloff, Paul C et al. (2007) Response facilitation from the ""suppressive"" receptive field surround of macaque V1 neurons. J Neurophysiol 98:2168-81

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