A dendritic spine is a very small structure  } of a neuron that processes input timing information. Why are spines so small? Here, we provide functional reasons; the size of spines is optimal for probability codingof Ca2+ increases, which makes robust and sensitive to input timing information . We created a stochastic simulation model of input timing-dependent Ca2+ increases in a cerebellar Purkinje cells spine. Spines used probability coding of Ca2+ increases rather than amplitude coding for input timing detection via stochastic facilitation by utilizing the small number of molecules in a spine volume, which appeared optimalfor probability coding . Probability coding of Ca2+ increases in a spine volume was more robust against input fluctuation and more sensitive to input numbers than amplitude coding of Ca2+ increases in a cell volume. Thus, stochasticity is a strategy by which neurons robustly and sensitively code information.
A dendritic spine is a very small structure (~0.1 \mu}m^3) of a neuron that processes input timing information. Why are spines so small? Here, we provide functional reasons; the size of spines is optimal for information coding. Spines code input timing information by the probability of Ca^{2+ increases, which makes robust and sensitive information coding possible . We created a stochastic simulation model of input timing-dependent Ca^{2+ increases in a cerebellar Purkinje cell's spine. Spines used probability coding of Ca^{2+ increases rather than amplitude coding for input timing detection via stochastic facilitation by utilizing the small number of molecules in a spine volume, where information per volume appeared optimal . Probability coding of Ca^{2+ increases in a spine volume was more robust against input fluctuation and more sensitive to input numbers than amplitude coding of Ca^{2+ increases in a cell volume. Thus, stochasticity is a strategy by which neurons robustly and sensitively code information.
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(~0.1
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probability codingof Ca2+
information coding. Spines code input timing information by the probability of Ca^{2+
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to input timing information
information coding possible
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Ca^{2+
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cells
cell's
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which appeared optimalfor probability coding
where information per volume appeared optimal
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Ca^{2+
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