Multivariate objective response detectors (MORD): statistical tools for multichannel EEG analysis during rhythmic stimulation.
The presence of cerebral evoked responses can be tested by using objective response detectors. They are statistical tests that provide a threshold above which responses can be assumed to have occurred. The detection power depends on the signal-to-noise ratio (SNR) of the response and the amount of data available. However, the correlation within the background noise could also affect the power of such detectors. For a fixed SNR, the detection can only be improved at the expense of using a longer stretch of signal. This can constitute a limitation, for instance, in monitored surgeries. Alternatively, multivariate objective response detection (MORD) could be used. This work applies two MORD techniques (multiple coherence and multiple component synchrony measure) to EEG data collected during intermittent photic stimulation. They were evaluated throughout Monte Carlo simulations, which also allowed verifying that correlation in the background reduces the detection rate. Considering the N EEG derivations as close as possible to the primary visual cortex, if N = 4, 6 or 8, multiple coherence leads to a statistically significant higher detection rate in comparison with multiple component synchrony measure. With the former, the best performance was obtained with six signals (O1, O2, T5, T6, P3 and P4).
Felix
Leonardo Bonato
LB
Departamento de Engenharia Elétrica e de Produção, Universidade Federal de Viçosa, Av. P.H. Rolfs s/n--Campus, CEP 36570000, Vicosa, MG, Brazil. leobonato@ufv.br
Miranda de Sá
Antonio Mauricio Ferreira Leite
AM
Infantosi
Antonio Fernando Catelli
AF
Yehia
Hani Camille
HC
D000161:Acoustic Stimulation; D000293:Adolescent; D002648:Child; D003627:Data Interpretation, Statistical; D004569:Electroencephalography; D006801:Humans; D009010:Monte Carlo Method; D015999:Multivariate Analysis; D010775:Photic Stimulation