Our long-range research interest is to understand the functional organization of the adult sensory cortex and its plasticity. The target of our research is the somatosensory cortex of the adult rat, especially the subdivision that processes information from the whiskers known as Postero Medial Barrel Sub Field (PMBSF). We have demonstrated that the size of a whisker functional representation (WFR) in the PMBSF is large and consequently overlap extensively with the WFRs of other whiskers. We have also demonstrated that the size of the WFR in the cortex is mutable following changes in the patterns of sensory input. For example, after removal of all its neighboring whiskers, a spared (remaining) WFR could expand dramatically. However, when such whisker-deprived rats were removed from their home cages and given brief opportunity to explore a novel environment, an unexpected strong contraction of the spared whisker's WFR was found. The degree of contraction of the spared whisker WFR became more pronounced with increasing amount of time actually spent exploring the environment with the remaining whiskers. We propose to extend these findings from whisker-deprived rats to non-deprived rats. Our general hypothesis is that solitary confinement of the laboratory rat to the typical small and bare cage is an inadvertent form of sensory deprivation that lead to abnormally expanded sensory representation in the cortex. If correct, conditions that promote natural, innate behavior in rats such as tunnel digging, navigation, foraging and social interactions - by transferring rats from their home cage to a new kind of an 'enriched environment' (EE) - can refine cortical functional organization by inducing a contraction of cortical representations and consequently reducing their overlap, a refinement verified by our preliminary results. Using functional imaging, single unit recordings and anatomical techniques we propose to characterize functional and anatomical aspects of such plasticity, its time course, and its effects on neuronal activity patterns and receptive field characteristics within PMBSF. We also propose to study whether exposure to an EE endows the cortex with some immunity to the deprivation effects of the standard cage. Successful completion of our proposal should have major implications for both basic and clinical research because they question the relevance of caged, laboratory rat brain to serve as a model for the brain of humans in their natural environments. In addition, such findings could have important implications for treatment of adult perceptual/motor disorders. ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS043165-02
Application #
6749037
Study Section
Integrative, Functional and Cognitive Neuroscience 8 (IFCN)
Program Officer
Babcock, Debra J
Project Start
2003-07-01
Project End
2007-06-30
Budget Start
2004-07-01
Budget End
2005-06-30
Support Year
2
Fiscal Year
2004
Total Cost
$323,831
Indirect Cost
Name
University of California Irvine
Department
Other Basic Sciences
Type
Schools of Arts and Sciences
DUNS #
046705849
City
Irvine
State
CA
Country
United States
Zip Code
92697
Frostig, Ron D; Chen-Bee, Cynthia H; Johnson, Brett A et al. (2017) Imaging Cajal's neuronal avalanche: how wide-field optical imaging of the point-spread advanced the understanding of neocortical structure-function relationship. Neurophotonics 4:031217
Weber, Jessie R; Cuccia, David J; Johnson, William R et al. (2011) Multispectral imaging of tissue absorption and scattering using spatial frequency domain imaging and a computed-tomography imaging spectrometer. J Biomed Opt 16:011015
Chen-Bee, Cynthia H; Agoncillo, Teodora; Lay, Christopher C et al. (2010) Intrinsic signal optical imaging of brain function using short stimulus delivery intervals. J Neurosci Methods 187:171-82
Abookasis, David; Lay, Christopher C; Mathews, Marlon S et al. (2009) Imaging cortical absorption, scattering, and hemodynamic response during ischemic stroke using spatially modulated near-infrared illumination. J Biomed Opt 14:024033
Frostig, Ron D; Xiong, Ying; Chen-Bee, Cynthia H et al. (2008) Large-scale organization of rat sensorimotor cortex based on a motif of large activation spreads. J Neurosci 28:13274-84
Chen-Bee, Cynthia H; Agoncillo, Teodora; Xiong, Ying et al. (2007) The triphasic intrinsic signal: implications for functional imaging. J Neurosci 27:4572-86
Frostig, Ron D (2006) Functional organization and plasticity in the adult rat barrel cortex: moving out-of-the-box. Curr Opin Neurobiol 16:445-50
Polley, Daniel B; Rickert, Jessica L; Frostig, Ron D (2005) Whisker-based discrimination of object orientation determined with a rapid training paradigm. Neurobiol Learn Mem 83:134-42
Prakash, Neal; Frostig, Ron D (2005) What has intrinsic signal optical imaging taught us about NGF-induced rapid plasticity in adult cortex and its relationship to the cholinergic system? Mol Imaging Biol 7:14-21