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

Automated classification of evoked quantal events

“…While the method for classification to "release/failure" still works if there are many multiple release events in a single trace, the computation of the functionals currently only works for single release events. We do not currently have a computational method for separating a multiple release event into its constituent pieces; however various approaches have been develop to use deconvolution techniques of multi-quantal evoked events at NMJs (Bykhovskaia et al, 1996).…”

Making quantal analysis more convenient, fast, and accurate: User-friendly software QUANTAN

“…3 A, B, arrowheads). QUANTAN incorporates an earlier developed procedure (Bykhovskaia et al, 1996) for accurate detection of inflections and peaks of current traces.…”

“…To accurately detect EPSCs, mEPSCs, or multiple quantal peaks in a single EPSC, we improved and further developed an earlier version of our detection software (Bykhovskaia et al, 1996). Digitized and differentiated recordings are analyzed to determine the following parameters for each EPSC or mEPSC (a response): 1) onset; 2) duration; 3) latencies and amplitudes of multiple quantal peaks or inflections, if they are present (Fig.…”

“…The software performs multiple tasks required for statistical analysis of transmitter release, including filtering of electrical recordings, event detection, analysis of the release time-course, separation of synchronous and asynchronous release components, calculation of quantal content and its variability, and fitting the quantal release by binomial and Poissionian statistical models. QUANTAN combines our previously developed algorithms for direct quantal counts at low-output synapses (Bykhovskaia et al, 1996) and deconvolution of the distribution of EPSC sizes at high-output synapses (Vorobieva et al, 1999); further, it incorporates an algorithm for evaluation of the accuracy of direct quantal counts, which facilitates the choice for the appropriate detection method. Furthermore, it employs several different methods to calculate quantal content, thus possible errors can be assessed.…”

“…Under the conditions when multiquantal responses are infrequent and the instrumental noise is sufficiently low, quanta can be detected visually (Katz and Miledi, 1965;Wernig, 1972;Zucker, 1973) as inflections or multiple peaks of EPSP traces. A software package that performs this procedure automatically by analyzing differentiated signals has been created (Bykhovskaia et al, 1996).…”