Application to biomedical signals - Practical Biomedical Signal Analysis Using MATLAB - page 122

FIGURE 4.10: The propagation of EEG activity during overnight sleep averaged
over nine subjects, estimated by means of DTF integrated in the 0-30 Hz band.
Arrows are drawn for DTFs greater than 0.06. Their intensities are reflected by the
shade of arrows. From [Kaminski et al., 1997].

sitive to volume conduction. In case of PDC the same provisions concerning signal
preprocessing have to be made.
PDC have been used, e.g., by [Fanselow et al., 2001] for the study of thalamic
bursting in rats during different awake behavioral states, by [Astolfi et al., 2006]
for assessing functional connectivity, and for investigation of epileptic activity by
[Baccala et al., 2004, Takahashi et al., 2007]. In the last paper the statistical properties
of PDC were analyzed. The properties of PDC were considered also in [Schelter
et al., 2009], where the problems connected with interpretation of PDC were raised
and a new normalization similar to the one applied in DTF was proposed.

4.1.6.3 Sleep EEG analysis

Sleep EEG reveals a characteristic pattern called a sleep architecture, which is
classically described by division into stages originally defined by [Rechtschaffen
and Kales, 1968] (R&K): stage 1 (drowsiness), stage 2 (light sleep), stage 3 (deep
sleep), stage 4 (very deep sleep), and REM (dreaming period accompanied by rapid