The membrane of most gastrointestinal smooth muscles shows slow waves, slow rhythmic changes in membrane potential. Slow waves serve to bring the membrane potential of smooth muscle cells to a threshold level that elicits a second electrical event known as the spike or action potential. The inward current of the spike, in most gastrointestinal smooth muscle preparations, is carried, at least in...

Neostriatal cholinergic interneurons produce spontaneous tonic firing in the absence of synaptic input. Perforated patch recording and whole-cell recording combined with calcium imaging were used in vitro to identify the intrinsic membrane properties underlying endogenous excitability. Spontaneous firing was driven by the combined action of a sodium current and the hyperpolarization-activated c...

Ranganathan GN, Koester HJ. Optical recording of neuronal spiking activity from unbiased populations of neurons with high spike detection efficiency and high temporal precision. J Neurophysiol 104: 1812–1824, 2010. First published July 7, 2010; doi:10.1152/jn.00197.2010. Activity in populations of neurons is essential for cortical function including signaling of information and signal transport...

Long-term modification of synaptic strength is one of the basic mechanisms of memory formation and activity-dependent refinement of neural circuits. This idea was purposed by Hebb to provide a basis for the formation of a cell assembly. Repetitive correlated activity of pre-synaptic and post-synaptic neurons can induce long-lasting synaptic strength modification, the direction and extent of whi...

When an action potential enters a synaptic terminal, voltage-gated calcium channels open, allowing calcium ions to enter and promote synaptic vesicle release. How many vesicles are released depends on the number of release sites and the density and location of calcium channels. If channels are close to release sites, incoming ions quickly bind to vesicle-associated calcium sensors, and relative...

Calcium oscillations regulate several cellular processes by activating particular proteins. Most theoretical studies focused on the idealized situation of infinitely long oscillations. Here we analyze information transfer by time-limited calcium spike trains. We show that proteins can be selectively activated in a resonance-like manner by time-limited spike trains of different frequencies, whil...

Spike timing-dependent plasticity (STDP) experiments have shown that a synapse is strengthened when a presynaptic spike precedes a postsynaptic one and depressed vice versa. The canonical form of STDP has been shown to have an asymmetric shape with the peak long-term potentiation at +6 ms and the peak long-term depression at -5 ms. Experiments in hippocampal cultures with more complex stimuli s...

Two-photon calcium imaging is an emerging experimental technique that enables the study of information processing within neural circuits in vivo. While the spatial resolution of this technique permits the calcium activity of individual cells within the field of view to be monitored, inferring the precise times at which a neuron emits a spike is challenging because spikes are hidden within noisy...

Various forms of synaptic plasticity, including spike timing-dependent plasticity, can be accounted for by calcium-dependent models of synaptic plasticity. However, recent results in which synaptic plasticity is induced by multi-spike protocols cannot simply be accounted for by linear superposition of plasticity due to spike pairs or by existing calcium-dependent models. In this paper, we show ...