Abstract
Changes in latency of evoked potentials (EP) may indicate clinically and diagnostically important changes in the status of the nervous system. A low signal-to-noise ratio of the EP signal makes it difficult to estimate small, transient, time-varying changes in latency, or delays. Here, we present an adaptive algorithm that estimates small delay (latency change) values even when EP signal amplitudes are time-varying. When the delay is time invariant, the adaptive algorithm produces an unbiased estimate with delay estimation error less than half of the sampling interval. A lower estimation error variance is obtained when, in a pair of signals, the adaptive algorithm delays the signal with the higher SNR. The adaptive delay estimation algorithm was tested on intra-operative recordings of somatosensory EP, and analysis of those recordings reveals that the anesthetic etomidate produces a step change in the amplitude and latency of the EP signals.
Original language | English (US) |
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Pages (from-to) | 189-197 |
Number of pages | 9 |
Journal | IEEE Transactions on Biomedical Engineering |
Volume | 43 |
Issue number | 2 |
DOIs | |
State | Published - Feb 1996 |
ASJC Scopus subject areas
- Biomedical Engineering