TY - JOUR
T1 - Time-frequency analysis using damped-oscillator pseudo-wavelets
T2 - Application to electrophysiological recordings
AU - Hsu, David
AU - Hsu, Murielle
AU - Grabenstatter, Heidi L.
AU - Worrell, Gregory A.
AU - Sutula, Thomas P.
N1 - Funding Information:
DH was supported by the NIH Loan Repayment Program . TPS was supported by NIH R01-25020 . GAW was supported by NIH R01-NS63039-01 .
PY - 2010/12/15
Y1 - 2010/12/15
N2 - The damped-oscillator pseudo-wavelet is presented as a method of time-frequency analysis along with a new spectral density measure, the data power. An instantaneous phase can be defined for this pseudo-wavelet, and it is easily inverted. The data power measure is tested on both computer generated data and in vivo intrahippocampal electrophysiological recordings from a rat. The data power spectral density is found to give better time and frequency resolution than the more conventional total energy measure, and additionally shows intricate time-frequency structure in the rat that is altered in association with the emergence of epilepsy. With epileptogenesis, the baseline theta oscillation is severely degraded and is absorbed into a broader gamma band. There are also broad 600. Hz and 2000. Hz bands which localize to hippocampal layers that are distinct from those of the theta and gamma bands. The 600. Hz band decreases in prominence with epileptogenesis while the 2000. Hz band increases in prominence. The origins of these high frequency bands await further study. In general, we find that the damped-oscillator pseudo-wavelet is easy to use and is particularly suitable for problems where a wide range of oscillator frequencies is expected.
AB - The damped-oscillator pseudo-wavelet is presented as a method of time-frequency analysis along with a new spectral density measure, the data power. An instantaneous phase can be defined for this pseudo-wavelet, and it is easily inverted. The data power measure is tested on both computer generated data and in vivo intrahippocampal electrophysiological recordings from a rat. The data power spectral density is found to give better time and frequency resolution than the more conventional total energy measure, and additionally shows intricate time-frequency structure in the rat that is altered in association with the emergence of epilepsy. With epileptogenesis, the baseline theta oscillation is severely degraded and is absorbed into a broader gamma band. There are also broad 600. Hz and 2000. Hz bands which localize to hippocampal layers that are distinct from those of the theta and gamma bands. The 600. Hz band decreases in prominence with epileptogenesis while the 2000. Hz band increases in prominence. The origins of these high frequency bands await further study. In general, we find that the damped-oscillator pseudo-wavelet is easy to use and is particularly suitable for problems where a wide range of oscillator frequencies is expected.
KW - Epileptogenesis
KW - High frequency oscillations
KW - Time-frequency analysis
KW - Wavelet analysis
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U2 - 10.1016/j.jneumeth.2010.09.019
DO - 10.1016/j.jneumeth.2010.09.019
M3 - Article
C2 - 20933002
AN - SCOPUS:78649510474
SN - 0165-0270
VL - 194
SP - 179
EP - 192
JO - Journal of Neuroscience Methods
JF - Journal of Neuroscience Methods
IS - 1
ER -