The role of intra-striatal synaptic interactions for shaping cortico-striatal network dynamics
Jovana Belić (Royal Institute of Technology (KTH), Stockholm and Bernstein Center Freiburg), Andreas Klaus (Karolinska Institutet (KI), Stockholm and National Institute of Mental Health (NIH), Bethesda, USA), Dietmar Plenz (National Institute of Mental Health (NIH), Bethesda, USA), Jeanette Hellgren Kotaleski (Royal Institute of Technology (KTH), Stockholm and Karolinska Institutet (KI), Stockholm )
Neuronal avalanches are a type of spontaneous activity first observed in vitro by recording local field potentials in cortical neural networks using slices of rat cortex as well as cultured networks . Propagation of spontaneous activity is balanced and shows a branching parameter close to 1. In addition, the number of electrodes driven over threshold during activity is distributed approximately like a power law with an exponent of -3/2 for event sizes suggesting a critical dynamics . Neural avalanches have been shown to provide: optimal information transmission [5, 6], maximal information capacity  and maximal dynamic range .
We are studying simultaneously striatal and cortical activity in vitro. Preliminary results show that neuronal avalanches in cortex induce activity clusters in striatum whose size distribution can be approximated by a steeper power law than observed in cortex. Based on this we have developed network models in order to determine the impact of different striatal neurons on the more negative exponent. In particular, we are investigating whether FS or MS neurons have any roles in shaping the striatal dynamics.
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