Signal processing of the auditory brainstem response: investigation into the use of discrete wavelet analysis

Multiresolutional wavelet analysis of the auditory brainstem response (ABR) in the time frequency domain (TFD) has immense potential for improving this test's sensitivity and specificity as a diagnostic assessment tool, but the choice of wavelet remains a problem. This study compared the clinical significance, as versus the obvious mathematical significance, of using Daubechies 5, symlet 4, and biorthogonal 3.5 wavelet techniques to obtain ABR TFD results in normal subjects. The wavelet techniques showed multiple statistical differences between their TFD results, with a significant number being clinically significant, particularly for TFD component amplitudes. These findings warn against the clinical comparison of TFD ABR results obtained using different wavelets and reinforces the need to state specifically the wavelet procedures used when conducting clinical ABR multiresolutional wavelet analysis.