An algorithm for high-resolution detection of postsynaptic quantal events in extracellular records

A software package has been developed for the detection and measurement of extracellularly recorded postsynaptic quantal events evoked by neural stimulation. The algorithm is based on the identification of monotonic regions of a differentiated current signal and detects the small inflections and peaks of a postsynaptic response that result from the asynchronous presynaptic release of individual packets of neurotransmitter. Recorded and simulated postsynaptic responses have been used to verify the accuracy of the algorithm and to determine its resolution. The algorithm can accurately detect up to six individual quanta in a time period of 20 ms, with a resolution of 0.5-1.0 ms.