Executive functions and prefrontal cortex: a matter of persistence?
Gareth Ball, Paul R Stokes, Rebecca A Rhodes, Subrata K Bose, Iead Rezek, Alle-Meije Wink, Louis-David Lord, Mitul A Mehta, Paul M Grasby, Federico E Turkheimer
Frontiers in Systems Neuroscience | Published : 2011
Executive function is thought to originates from the dynamics of frontal cortical networks. We examined the dynamic properties of the blood oxygen level dependent time-series measured with functional MRI (fMRI) within the prefrontal cortex (PFC) to test the hypothesis that temporally persistent neural activity underlies performance in three tasks of executive function. A numerical estimate of signal persistence, the Hurst exponent, postulated to represent the coherent firing of cortical networks, was determined and correlated with task performance. Increasing persistence in the lateral PFC was shown to correlate with improved performance during an n-back task. Conversely, we observed a corre..View full abstract