ERP P300 Peak Latency
Measure sampled positive peak latency in an explicitly supplied inclusive P300 analysis window. Times are relative to stimulus onset, ties select the earliest sample, and at least one positive amplitude is required. Component identification and preprocessing belong to the caller.
Description
A sampled P300-window peak measure locates the largest positive ERP sample in a declared time interval.
A sampled P300-window peak measure locates the largest positive ERP sample in a declared time interval. Component identity and preprocessing precede this numeric selection.1
Measure sampled positive peak latency in an explicitly supplied inclusive P300 analysis window. Times are relative to stimulus onset, ties select the earliest sample, and at least one positive amplitude is required. Component identification and preprocessing belong to the caller.
When to use ERP P300 Peak Latency
Use this tool to measure sampled positive peak latency in an explicitly supplied inclusive P300 analysis window. Times are relative to stimulus onset, ties select the earliest sample, and at least one positive amplitude is required. Component identification and preprocessing belong to the caller.
Prepare the task-specific rates, comparable response-time means, identified spike train, processed ERP or estimated spectra requested. Confirm units, preprocessing, sample pairing and caller-fitted model coefficients.
How to use ERP P300 Peak Latency and understand its results
- Prepare the task-specific rates, comparable response-time means, identified spike train, processed ERP or estimated spectra requested. Confirm units, preprocessing, sample pairing and caller-fitted model coefficients.
- Enter timesMs, amplitudesUv, windowStartMs, windowEndMs using the field table and calculation rules, then run the tool.
- Read latencyMs, peakAmplitudeUv. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| timesMs | Ascending sample times relative to stimulus onset. (ms) | list of number; minimum entries: 1; maximum entries: 100000 | Required |
| amplitudesUv | Baseline-referenced ERP sample amplitudes. (uV) | list of number; minimum entries: 1; maximum entries: 100000 | Required |
| windowStartMs | Inclusive analysis window start. (ms) | number; minimum: 0 | Required |
| windowEndMs | Inclusive analysis window end. (ms) | number; minimum: 0 | Required |
Enter aligned nonempty ascending finite times in stimulus-relative milliseconds and finite baseline-referenced microvolt amplitudes. Use nonnegative ordered window endpoints. Return selected time/amplitude; reject absent positive in-window samples. Equal peaks choose the earliest time.
peak=earliest maximum positive amplitude within inclusive [windowStart,windowEnd] Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| latencyMs | Time of the maximum positive sample in the window. (ms) | number; minimum: 0 |
| peakAmplitudeUv | Amplitude of the selected sample. (uV) | number; strictly above: 0 |
{
"input": {
"timesMs": [
0,
200,
300,
400,
500,
700
],
"amplitudesUv": [
0,
2,
6,
5,
3,
9
],
"windowStartMs": 200,
"windowEndMs": 600
},
"output": {
"latencyMs": 300,
"peakAmplitudeUv": 6
}
}Limitations and assumptions
No EEG filtering, baseline correction, component detection or interpolation is performed. A positive sample selected in the window is not by itself a confirmed P300 component.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use EEG Alpha Peak Frequency: Find the supplied PSD bin with maximum power in [8, 12) Hz under the MNE alpha convention, choosing the lowest frequency on a tie. The grid need not be uniform; no interpolation or physiological classification is performed. For a complementary task, use Stroop Interference: Calculate the signed stroop interference as mean incongruent response time minus mean congruent response time in milliseconds, using caller-prepared comparable correct-trial means.
References
-
ERP P300 Peak Latency — tool.io
Similar or alternative tools
- EEG Alpha Peak Frequency
Find the supplied PSD bin with maximum power in [8, 12) Hz under the MNE alpha convention, choosing the lowest frequency on a tie. The grid need not be uniform; no interpolation or physiological classification is performed.
- Stroop Interference
Calculate the signed stroop interference as mean incongruent response time minus mean congruent response time in milliseconds, using caller-prepared comparable correct-trial means.