We are interested in how high frequency (30+ Hz) brains oscillations are generated using the mouse olfactory bulb as our model system. These oscillations are a prominent feature of neural activity in many brain areas including the olfactory system. The mechanisms that underlie these oscillations, as well as the functional role they play are poorly understood, but they have recently been implicated in many aspects of brain function and disease. In the previous funding period, we have described a novel mechanism, called stochastic synchrony, by which correlated fast fluctuating inputs can generate synchronous gamma-frequency (30-80Hz) oscillations in populations of neurons. While much of our previous work used olfactory bulb neurons as a model system for analysis of this novel mechanism of synchronization, this prior work ignored many details of olfactory bulb neurons and circuits in order to describe the general features of this phenomenon. In this application we propose to extend our previous work by considering how key features of olfactory bulb circuitry and physiology modulate stochastic synchrony. We are particularly interested in whether the observed heterogeneity of neural properties is a useful feature of neural networks or is a "bug" that results from the intrinsic imprecision of biological systems. Homogeneity should enhance synchrony but recent data suggests that heterogeneity across neurons of the same type may provide certain functional advantages. We are also interested in how the synaptic connectivity of the olfactory bulb may facilitate or disrupt synchrony. Exploring these mechanisms will improve our understanding of the function and disorders of synchrony, especially in the context of the vertebrate olfactory system

Public Health Relevance

Activity of neurons in the olfactory system represents information about sensory stimuli in the environment. One of our long term goals is to understand how to interpret features of neuronal activity as representing features of olfactory stimuli. To accomplish this goal we believe that it is critical to develop our understanding of the dynamics of neuronal activity through the use of experiments and computational models. In this proposal we describe an integrated experimental and computational approach to analysis of the mechanisms of patterns of periodic synchronized activity in the olfactory system. In particular we want to understand how the detailed and diverse biophysical and synaptic properties of olfactory bulb neurons contribute to the generation of patterned activity.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Research Project (R01)
Project #
5R01DC011184-08
Application #
8518055
Study Section
Neurotechnology Study Section (NT)
Program Officer
Sullivan, Susan L
Project Start
2006-09-01
Project End
2015-07-31
Budget Start
2013-08-01
Budget End
2014-07-31
Support Year
8
Fiscal Year
2013
Total Cost
$287,934
Indirect Cost
$71,513
Name
Carnegie-Mellon University
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
052184116
City
Pittsburgh
State
PA
Country
United States
Zip Code
15213
Burton, Shawn D; Urban, Nathaniel N (2014) Greater excitability and firing irregularity of tufted cells underlies distinct afferent-evoked activity of olfactory bulb mitral and tufted cells. J Physiol 592:2097-118
Tripathy, Shreejoy J; Savitskaya, Judith; Burton, Shawn D et al. (2014) NeuroElectro: a window to the world's neuron electrophysiology data. Front Neuroinform 8:40
Padmanabhan, Krishnan; Urban, Nathaniel N (2014) Disrupting information coding via block of 4-AP-sensitive potassium channels. J Neurophysiol 112:1054-66
Arthur, Joseph G; Burton, Shawn D; Ermentrout, G Bard (2013) Stimulus features, resetting curves, and the dependence on adaptation. J Comput Neurosci 34:505-20
Gerkin, Richard C; Tripathy, Shreejoy J; Urban, Nathaniel N (2013) Origins of correlated spiking in the mammalian olfactory bulb. Proc Natl Acad Sci U S A 110:17083-8
Ventura, Valerie; Gerkin, Richard C (2012) Accurately estimating neuronal correlation requires a new spike-sorting paradigm. Proc Natl Acad Sci U S A 109:7230-5
Oswald, Anne-Marie M; Urban, Nathaniel N (2012) Interactions between behaviorally relevant rhythms and synaptic plasticity alter coding in the piriform cortex. J Neurosci 32:6092-104
Padmanabhan, Krishnan; Urban, Nathaniel N (2010) Intrinsic biophysical diversity decorrelates neuronal firing while increasing information content. Nat Neurosci 13:1276-82