The detection of adult cortical auditory evoked potentials (CAEPs) using an automated statistic and visual detection

The detection of adult cortical auditory evoked potentials (CAEPs) can be challenging when the stimulus is just audible. The effectiveness of a statistic compared with expert examiners in (1) detecting the presence of CAEPs when stimuli were present, and (2) reporting the absence of CAEPs when no stimuli were present, was investigated. CAEPs recorded from ten adults, using two speech-based stimuli, five stimulus presentation levels, and non-stimulus conditions, were given to four experienced examiners who were asked to determine if responses to auditory stimulation could be observed, and their degree of certainty in making their decision. These recordings were also converted to multiple dependent variables and Hotelling's T2 was applied to calculate the probability that the mean value of any linear combination of these variables was significantly different from zero. Results showed that Hotelling's T2 was equally sensitive to the best of individual experienced examiners in differentiating a CAEP from random noise. It is reasonable to assume that the difference in response detection for a novice examiner and Hotelling's T2 would be even greater. Sumario La deteccin de los potenciales evocados auditivos corticales (CAEP) del adulto puede ser un desafo cuando el estmulo es apenas audible. Se investig la efectividad de una comparacin estadstica con examinadores expertos para (1) detectar la presencia del CAEP cuando el estimulo estuvo presente, y (2) reportar la ausencia del CAEP cuando ningn estmulo estaba presente. Los CAEP registrados para diez adultos, usando dos estmulos con base en lenguaje, cinco niveles de presentacin del estmulo, y condiciones sin estmulo, fueron presentados a cuatro examinadores con experiencia, a quienes se solicit que determinaran si las respuestas a estmulos auditivos podan ser observadas y su grado de certeza en la toma de sus decisiones. Estos registros fueron tambin convertidos a mltiples variables dependientes y se aplic el T2 de Hotelling para calcular la probabilidad de que el valor medio de una combinacin lineal de estas variables fuera significativamente diferente de cero. Los resultados mostraron que el T2 de Hotelling era igualmente sensible que lo mejor de los examinadores experimentados individuales para diferenciar un CAEP de un ruido aleatorio. Es razonable asumir que la diferencia en deteccin de respuestas para un examinador novato y el T2 de Hotelling seran an mayor.