A comparison of methods for assessing alpha phase resetting in electrophysiology, with application to intracerebral EEG in visual areas

Auditory Event-Related Response in Visual Cortex Modulates Subsequent Visual Responses in Humans

“…Therefore, further tests would need to be applied. However, such tests work only for signals with high signal-to-noise ratios, and are probably unsuited for EEG data (Krieg et al, 2011). Thus, our pattern of results would also be consistent with an evoked oscillation.…”

Analysis of stimulus-related activity in rat auditory cortex using complex spectral coefficients

“…The phase STM measure merits some additional comments. This measure, the second trigonometric moment, or STM (Krieg et al 2011), tries to capture any phase concentrations that may occur as the result of a stimulus and attempts to correct for the possibility that phase concentration is due to an additive shift in the complex coefficients by first subtracting the mean C and then measuring the uniformity of phase values such that a bimodal distribution results in high values of the measure and a uniform distribution results in low values.…”

“…The contribution to evoked responses of phase reset vs. additive components continues to be hotly debated, and previous studies in humans investigating the origin of the evoked response and the contribution of phase reset have reached contradictory conclusions Krieg et al 2011;Jervis et al 1983;Makeig et al 2002;Makinen et al 2005;Sauseng et al 2007;Sayers et al 1974). Detailed analyses and simulations have shown that it is often difficult to conclude unequivocally that observed phase concentrations are due to phase resets per se rather than an additive component (Krieg et al 2011;Sauseng et al 2007).…”

“…However, commonly used measures of phase reset such as intertrial coherence (ITC) (Lakatos et al 2007;Makeig et al 2002;Tallon-Baudry et al 1996) are particularly susceptible to confounds due to additive components (Krieg et al 2011;Martinez-Montes et al 2008;Yeung et al 2004), and other methods are susceptible to this confound, as well (e.g., Jansen et al 2003; for a more complete discussion, see Krieg et al 2011). Thus, as for evoked vs. induced components, phase reset and additive components can become entangled, complicating their interpretation, and the contribution of phase reset to auditory SRSPs remains controversial Jervis et al 1983;Krieg et al 2011;Makeig et al 2002;Makinen et al 2005;Sauseng et al 2007;Sayers et al 1974). In this article, we present and discuss methods to separate these components that would be useful for simplifying their interpretation.…”

“…Thus substantial information about underlying cortical processes may be gained via spectral decomposition, most typically via time-frequency analysis (Jordan et al 1997), which yields spectrograms that portray the evolution of frequency-specific activity over time relative to stimulus onset. The utility of analyzing complex spectral coefficients for disentangling evoked, induced, and phase reset response components has been highlighted recently (Krieg et al 2011;Martinez-Montes et al 2008). In this analysis, the set of coefficients at each time-frequency point recorded over many trials and plotted in the complex plane was shown to exhibit specific stimulus-related behaviors depending on the components contributing to the response.…”