Where the BOLD signal goes when alpha EEG leaves

Frontal theta EEG activity correlates negatively with the default mode network in resting state

“…Evidence that an increase in high frequency oscillatory activity results in a BOLD increase in the DMN is provided by Laufs et al (2003b), who report a positive correlation between beta (17-23 Hz) amplitude and the BOLD signal in the DMN. The relationship between activity in cortical networks, oscillatory activity and hemodynamic measures in these cases can however be more complex than explained above and more comprehensive spectral EEG information may need to be correlated with hemodynamic measures (Laufs et al, 2006).…”

“…More recently, simultaneous EEG/ fMRI has been successfully applied to investigate cognitive phenomena such as performance monitoring (Debener et al, 2005) and sustained attention (Eichele et al, 2005). Apart from epilepsy research most studies have focused on the BOLD correlates of ongoing oscillatory activity during resting state (i.e., recorded while the subject was quietly lying in the scanner, with no explicit task), focusing on the posterior alpha rhythm and, to a lesser extent, the beta rhythm (Feige et al, 2005;Goldman et al, 2002;Goncalves et al, 2006;Laufs et al, 2006Laufs et al, , 2003aMoosmann et al, 2003). In these studies, the general idea has been that spontaneous fluctuations in the amplitude of a given oscillatory signal can be correlated with spontaneous fluctuations in the BOLD signal.…”

“…Studies investigating the BOLD correlates of spontaneous fluctuations in alpha activity (Feige et al, 2005;Goldman et al, 2002;Goncalves et al, 2006;Laufs et al, 2006Laufs et al, , 2003aMoosmann et al, 2003) have shown that the expected posterior visual regions and also other regions across the cortex are negatively correlated with posterior alpha fluctuations. Recent findings suggest that there is considerable individual variation in areas that correlate with the alpha fluctuations and that these can be linked to differences in the total power spectrum of an individual (Goncalves et al, 2006;Laufs et al, 2006).…”

“…Recent findings suggest that there is considerable individual variation in areas that correlate with the alpha fluctuations and that these can be linked to differences in the total power spectrum of an individual (Goncalves et al, 2006;Laufs et al, 2006). Laufs et al (2006) observed that negative alpha-BOLD correlations in posterior visual areas go together with relatively high theta power during alpha desynchronisation, while relative high beta power during an entire session is related to negative alpha-BOLD correlations in regions thought to be related to attention in the parietal and frontal lobes. A few studies (Laufs et al, 2003b;Moosmann et al, 2003) have also reported BOLD correlates of beta activity.…”

Feasibility of simultaneous intracranial EEG-fMRI in humans: A safety study

“…Indeed, despite its own limitations scalp EEG has previously been successfully combined with fMRI in study patients with epilepsy, providing unique new information on the haemodynamic correlates of paroxysmal discharges in a good proportion of cases studied to date [4][5][6][7][8]. Importantly, these include brain areas thought to be primarily responsible for the generation of interictal and ictal epileptic discharges visible on scalp EEG recordings [5,7,9,10]. However, EEG-fMRI studies in epilepsy have raised a number of important questions, for example; 1) is normal neurovascular coupling maintained, as in cognitive fMRI experiments [12][13][14][15][16]?…”