N to the described above cross-frequency (CF) modulations, Witte et al.

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(2005) introduced a hypothesis in regards to the "hierarchical" organization of EEG oscillations suggesting that the amplitude of the title= pnas.1408988111 oscillations at characteristic frequency is modulated by the oscillatory phase at lower frequency. In specific, they located that delta (1? Hz) phase modulates theta (four?0 Hz) amplitude, and theta modulates gamma (30?0 Hz) amplitude in main auditory cortex of awake macaque monkeys (Lakatos et al., 2005).N towards the described above cross-frequency (CF) modulations, Witte et al. (2008) described two more CFC forms: envelope to frequency and frequency to frequency. Within the data-based EEG burst simulations making use of coupled Duffing oscillators, the authors (Witte et al., 2008) discovered powerful envelope-envelope and envelope-frequency CFC within the delta (0.5?.5 Hz) as well as the alpha (7?1 or eight?2 Hz) bands and quadratic coupling utilizing bicoherence (BIC) among delta and alpha bands.pronounced for right rejections than for hits, although this CFC pattern in the hippocampus was inversely additional pronounced for hits than for correct rejections (Mormann et al., 2005). Applying intracranial recordings in human epilepsy sufferers, Axmacher et al. (2010a) showed (i) that simultaneous maintenance of numerous products in operating memory is accompanied by theta-gamma phase-amplitude CFC in the hippocampus, and title= jir.2014.0001 (ii) that upkeep of an rising quantity of products is associated with modulation of beta/gamma power by lowering theta frequency phase. In other words, modulating influence with the decrease theta phase on the beta/gamma activity supplies for higher operating memory load. Recently, Belluscio et al. (2012) discovered that theta-gamma phase-amplitude modulation within the CA1 region of rat hippocampus was accompanied by theta-gamma phase-phase modulations, a minimum of for slow (30?0 Hz) and midfrequency (50?0 Hz) gamma oscillators.DELTA-THETA/DELTA-ALPHA OSCILLATORY COUPLING As well as other CFCsBesides the cross low-frequency/high-frequency coupling (e.g., theta-gamma), there's proof (Lakatos et al., 2005; Schack et al., 2005; Cohen, 2008; Isler et al., 2008) that CFC exists also involving the low-frequency bands (e.g., delta-theta, delta-alpha, and theta-alpha). Isler et al. (2008) reported enhance in energy and coherence in the delta band elicited by novel sounds in an auditory novelty oddball process accompanied by CFC measured by BIC for delta-theta (1:3) and delta-alpha (1:4) relationships in widespread fronto-central, proper parietal, temporal, and occipital regions. In the , Paced auditory serial addition task; PEP, Preejection period; POMS, Profile of similar time, globally synchronized delta oscillations were phase coupled when it comes to cross-bicoherence (cBIC) to theta oscillations in central regions and to alpha oscillations in correct parietal and posterior regions. Working with CF m:n phase synchronization index (PSI), Schack et al. (2005) found a rise in upper alpha-theta phase synchronization involving correct posterior and left anterior web sites in a memory scanning process. The authors recommended that this CFC reflects the interplay amongst the central executive functions (theta) along with the reactivation of long-term memory codes in short-term memory (upper alpha). Within a competitive decision-making job Cohen et al. (2009b) discovered that alpha and beta amplitude in human medial frontal cortex was modulated by delta and theta phase; the strength of this modulation differed also among losses and wins, suggesting that this CF phase-amplitude coupling might reflect a coding mechanism of feedback valence data.