Spatial gradients and multidimensional dynamics in a neural integrator circuit

Princeton Neuroscience Institute and Department of Molecular Biology, Princeton University, Princeton, New Jersey, USA.
Nature Neuroscience (Impact Factor: 16.1). 08/2011; 14(9):1150-9. DOI: 10.1038/nn.2888
Source: PubMed


In a neural integrator, the variability and topographical organization of neuronal firing-rate persistence can provide information about the circuit's functional architecture. We used optical recording to measure the time constant of decay of persistent firing (persistence time) across a population of neurons comprising the larval zebrafish oculomotor velocity-to-position neural integrator. We found extensive persistence time variation (tenfold; coefficients of variation = 0.58-1.20) across cells in individual larvae. We also found that the similarity in firing between two neurons decreased as the distance between them increased and that a gradient in persistence time was mapped along the rostrocaudal and dorsoventral axes. This topography is consistent with the emergence of persistence time heterogeneity from a circuit architecture in which nearby neurons are more strongly interconnected than distant ones. Integrator circuit models characterized by multiple dimensions of slow firing-rate dynamics can account for our results.

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Available from: Aristides Arrenberg, Mar 07, 2014
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    • "Such results were interpreted to suggest the presence of neural integrators in the circuit, as velocity signals can be integrated to yield position signals (Robinson, 1989; Miri et al., 2011). Our finding that most sensorimotor striatal neurons are correlated with velocity suggests the possibility that a neural integrator is found in the basal ganglia circuitry. "
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    • "It now is possible to go beyond the traditional approaches used in monkey research, and to answer questions that were intractable in the past. For example, imaging of calcium signals makes it possible to record from many nearby neurons simultaneously with a temporal resolution that is good enough to capture the relationships between neural and behavioral or stimulus dynamics (Stosiek et al., 2003; Rothschild et al., 2010; Miri et al., 2011). Activation of specific subpopulations of neurons through optogenetics provides a carefully controlled tool for dissection of neural circuits in behaving animals (Han and Boyden, 2007). "
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