V. Perumalsamy et al. / J. Biomedical Science and Engineering 2 (2009) 294-303 303

SciRes Copyright © 2009 JBiSE

the discrimination power of our statistical test is unclear.

This can be determined empirically by repeating the test

many times on different realization for the data [20]. We

will consider this issue as part of our future research.

In summary, detection of sleep spindles using the sur-

rogate method proposed in this paper is shown to give

accurate results when applied to test the significance of

power spectral amplitudes. It is based on solid statistical

principles and overcomes some weaknesses in previous

methods for the same purpose. It is expected to become

a useful addition to the repertoire of nonlinear analysis

methods for neuroscience and other biomedical signal

processing applications.

6. ACKNOWLEDGEMENTS

The authors wish to express their kind thanks to Ms. Kristina Sus-

makova for providing EEG sleep data and invaluable help and discus-

sions.

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