Tolerance Data 2012 Greek FULL
DOWNLOAD >> https://geags.com/2t3M9q
Functional connectivity analysis, using independent component analysis, of the data from a 2012 study (Carhart-Harris et al., 2012), revealed increased DMN and task positive network (TPN) functional connectivity, therefore showing a decrease in DMN-TPN orthogonality after psilocybin (Carhart-Harris et al., 2013). Carhart-Harris et al. propose that increased DMN-TPN coupling in the presence of preserved thalamocortical connectivity is related to a state in which arousal is preserved but the distinction between inner thought and external focus becomes blurred.
Tagliazucchi et al. (2014) carried out a reanalysis of the previously published data from Carhart-Harris et al. (2012). Their new analyses were prompted by a view that more sensitive and specific indices might help to develop a better understanding of the neurobiology of conscious states, and specifically that measures that include variance over time might be especially informative. They note that the brain has been described as a system resting in (or near) a critical point or transition zone between states of order and disorder (see references in Tagliazucchi et al., 2014). They therefore tested the hypothesis that the brain can explore a maximal repertoire of its possible dynamic states in this critical zone, asking the question as to whether changes in spontaneous brain activity produced by psilocybin were consistent with displacement from this critical point, possibly moving toward a more entropic or supercritical state (Carhart-Harris et al., 2014). To test this hypothesis, the authors focused on variability in activity and functional connectivity parameters over time and presented empirical data that tested the hypothesis that brain activity becomes less ordered in the psychedelic state, with enhancement of the repertoire of possible states. The power spectrum density of the spectral content of spontaneous BOLD fluctuations can be characterized by a single parameter α, which condenses the scaling behavior and is demonstrative of the long-range temporal correlations of any given signal. Both BOLD signal variance and total spectral power measures showed increased variability after psilocybin, both in the temporal and spectral domain, with peaks in the ACC and bilateral hippocampus.