Detect artefact epochs in a PSG recording

Flags epochs containing likely artefacts based on amplitude thresholds, excessive high-frequency (muscle) power, and movement contamination. Operates on the EEG channels by default. Returns a logical vector (one value per epoch) and optionally attaches per-epoch artefact metrics for inspection.

Usage

detect_artifacts(
  psg,
  channels = NULL,
  amp_threshold_uv = 500,
  hf_band = c(40, 100),
  hf_percentile = 0.99,
  verbose = TRUE
)

Arguments

psg

An mrpheus_psg object from prepare_psg().

channels

Character vector. Channel labels to evaluate. If NULL (default), all non-bad EEG channels are used.

amp_threshold_uv

Numeric. Peak-to-peak amplitude threshold in µV. Epochs exceeding this in any selected channel are flagged. Default 500.

hf_band

Numeric vector of length 2. Frequency band (Hz) considered high-frequency / muscle contamination. Default c(40, 100).

hf_percentile

Numeric. Epochs whose HF power exceeds this percentile (across all epochs) are flagged. Default 0.99.

verbose

Logical. Print summary. Default TRUE.

Value

A tibble with one row per epoch and columns:

epoch

Integer. Epoch index (1-based).

artefact

Logical. TRUE if the epoch is flagged as artefact.

reason

Character. Comma-separated reasons for flagging, or NA.

peak_to_peak_uv

Numeric. Maximum peak-to-peak amplitude across selected channels.

hf_power_db

Numeric. Mean HF band power (dB) across selected channels.