Action Potential Amplitude
Measure sampled positive-going action-potential peak relative to an explicit baseline window; sampling and filtering can bias peak amplitude.
Description
An action-potential amplitude compares the event’s sampled maximum voltage with a preceding baseline mean.
An action-potential amplitude compares the event’s sampled maximum voltage with a preceding baseline mean. It does not require the baseline to be zero.
The tool returns baselineMv (baseline mv); peakMv (peak mv); amplitudeMv (amplitude mv). Input measurements and model parameters are supplied by the caller; the tool computes the stated summary rather than acquiring those measurements.
When to use Action Potential Amplitude
Use Action Potential Amplitude when you already have timesMs, voltagesMv, baselineStartMs, baselineEndMs, spikeStartMs, spikeEndMs and want baselineMv, peakMv, amplitudeMv. This is useful for checking a supplied calculation, documenting a measurement convention, or comparing observations prepared on the same basis.
How to use Action Potential Amplitude and understand its results
- Enter timesMs, voltagesMv, baselineStartMs, baselineEndMs, spikeStartMs, spikeEndMs using the field table below. Match the units, ordering and data boundaries described in the calculation.
- Run the tool after checking the stated bounds and matching paired observations or categories. A malformed request gives a tool error rather than a usable measurement.
- Read baselineMv, peakMv, amplitudeMv. Use the calculation and interpretation below to distinguish amounts, ratios, signs and decision flags where applicable.
- Review the supplied parameters and assumptions before using the result in a report or comparing it with another observation.
| Input field | Meaning | Value type and bounds | Requirement |
|---|---|---|---|
| timesMs | Times ms | list of number | Required |
| voltagesMv | Voltages mv | list of number | Required |
| baselineStartMs | Baseline start ms | number | Required |
| baselineEndMs | Baseline end ms | number | Required |
| spikeStartMs | Spike start ms | number | Required |
| spikeEndMs | Spike end ms | number | Required |
Require disjoint nonempty inclusive windows on strictly increasing aligned timestamps. The baseline must finish before the spike window begins.
amplitudeMv = max(spike-window voltage)−mean(baseline-window voltage) The symbols refer to the supplied quantities or generated values described above; unit conversions and comparison boundaries follow the stated implementation.
{
"input": {
"timesMs": [
0,
1,
2,
3
],
"voltagesMv": [
-70,
-70,
30,
-60
],
"baselineStartMs": 0,
"baselineEndMs": 1,
"spikeStartMs": 2,
"spikeEndMs": 3
},
"output": {
"baselineMv": -70,
"peakMv": 30,
"amplitudeMv": 100
}
}Limitations and assumptions
Peak timing, threshold detection and filtering are external. Sampling resolution can underestimate the true peak.
Numerical inputs must be finite. The tool checks its declared input shape and calculation constraints; those checks do not verify the quality, calibration or representativeness of the supplied observations.
Alternative or Complementary methods
Action Potential Rise Time: Interpolate fractional-amplitude rise time from a supplied positive spike rising limb and baseline/peak reference; the caller must isolate a single rising event. Spike Timing Precision: Derive per-trial stimulus-aligned first-spike latencies and inverse sample SD precision; identical latencies have undefined infinite precision and return an error.
Methodological background: Spike train variability.1
References
-
Spike train variability — Gerstner et al.; Neuronal Dynamics
Similar or alternative tools
- Action Potential Rise Time
Interpolate fractional-amplitude rise time from a supplied positive spike rising limb and baseline/peak reference; the caller must isolate a single rising event.
- Spike Timing Precision
Derive per-trial stimulus-aligned first-spike latencies and inverse sample SD precision; identical latencies have undefined infinite precision and return an error.