Computes the fractional area latency of an ERP component. This is the time point at which a specified fraction of the total area under the curve (in the given window) has accumulated.
Usage
eegERPlatency(
x,
window,
fraction = 0.5,
polarity = c("positive", "negative"),
epoch_start = 0,
assay_name = NULL
)Arguments
- x
A PhysioExperiment object with EEG data.
- window
Numeric vector of length 2:
c(start_ms, end_ms).- fraction
Fraction of total area (default: 0.5 for median latency).
- polarity
Expected polarity:
"positive"or"negative".- epoch_start
Start time of the epoch in milliseconds relative to stimulus onset. Default is 0 (epoch starts at stimulus).
- assay_name
Input assay name (default: first assay).
Value
A data.frame with columns: channel (character label),
latency_ms (numeric fractional area latency in milliseconds),
and fraction (numeric fraction used).
References
Luck, S. J. (2014). An Introduction to the Event-Related Potential Technique (2nd ed.). MIT Press.
Examples
if (FALSE) { # \dontrun{
pe <- make_eeg_erp(n_epochs = 40, sr = 250)
result <- eegERPlatency(pe, window = c(250, 500), fraction = 0.5,
polarity = "positive")
} # }