VecStim

VecStim is a stimulus object in the NEURON simulation environment that delivers presynaptic spike events at times specified by a Vector. Each entry in the Vector corresponds to a spike time in seconds from the start of the simulation, and at those times VecStim generates events that can drive postsynaptic mechanisms through NetCon connections.

Implementation and usage typically involve creating a Vector of spike times, creating a VecStim instance, and telling it to play the vector. For example, a Vector of times can be created or loaded, then the VecStim object is instructed to play that vector. The resulting events are then connected to postsynaptic targets via NetCon objects, so the same VecStim can drive multiple synapses or cells with identical spike timings.

VecStim provides deterministic, reproducible stimulation, making it suitable for replaying recorded spike trains or testing network responses to predefined sequences. It does not generate spikes by itself; instead, it relies on an external Vector of times. This makes it complementary to stochastic stimulus generators like NetStim, which can produce spikes based on probabilistic rules such as Poisson processes.

In practice, VecStim is commonly used to present precise temporal patterns to synapses and to study the effects of specific spike timings on network dynamics. It is often employed in conjunction with Vector, NetCon, and various synaptic mechanisms within NEURON.

See also: NetCon, Vector, Synapse, NetStim, NEURON.