Self-experimentation chronomics for health surveillance and science; also transdisciplinary civic duty?

Self-surveillance and self-experimentation are of concern to everyone interested in finding out the factors that increase one's risk of stroke from <8% to nearly 100%; one also thereby contributes to transdisciplinary science.

Phase synchronization between theta and upper alpha oscillations in a working memory task.

Motivated by findings that theta and upper alpha oscillations respond selectively to different types of memory demands, we investigated the role of phase synchronization in a memory scanning task. During retention, we found a load dependent increase in upper alpha power at O2 and P4 and a significant upper alpha:theta phase synchronization between right posterior, central and left anterior sites. During retrieval, a load dependent increase in upper alpha phase locking was observed at O2 and an increase in upper alpha:theta phase synchronization between right posterior and left anterior sites.

Increased neuronal communication accompanying sentence comprehension.

The main purpose of this study was to examine large-scale oscillatory activity and frequency-related neuronal synchronization during the comprehension of English spoken sentences of different complexity. Therefore, EEG coherence during the processing of subject-subject (SS)- and more complex subject-object (SO)-relatives was computed using an adaptive fitting approach of bivariate auto-regressive moving average (ARMA) models which enabled the continuous calculation of coherence in the course of sentence processing with a high frequency resolution according to the dynamic changes of the EEG signals. Coherence differences between sentence types were observed in the theta (4-7 Hz), beta-1 (13-18 Hz) and gamma (30-34 Hz) frequency ranges, though emerging during the processing of different parts of these sentences: gamma differences were evident mainly during the relative clause while theta and beta-1 differed significantly following the end of the relative clause.

The functional significance of theta and upper alpha oscillations.

Recent findings are reviewed indicating that upper alpha oscillations - when analyzed with appropriate time/ frequency resolution - show a similar physiological reactivity as theta in working memory tasks. Comparable to theta, a load dependent increase in power can be observed during retention and increased evoked activity during retrieval. During retrieval attempts theta behaves like a traveling wave spreading from anterior to posterior sites.

Quantification of phase synchronization phenomena and their importance for verbal memory processes.

In the past years, interest in brain oscillations and their possible role in perceptual and cognitive processes has greatly increased. The two oscillations that have received the most attention are the theta and the gamma rhythm. In this study, the functioning and properties of phase synchronization parameters for these two frequency bands estimated by means of Gabor expansion were demonstrated with simulations for the phase-locking index (PLI) and the 1:1 as well as n:m phase synchronization indices.