Functional connectivity in the motor cortex of resting human brain using echo‐planar mri

Abstract

An MRI time course of 512 echo-planar images (EPI) in resting human brain obtained every 250 ms reveals fluctuations in signal intensity in each pixel that have a physiologic origin. Regions of the sensorimotor cortex that were activated secondary to hand movement were identified using functional MRI methodology (FMRI). Time courses of low frequency (< 0.1 Hz) fluctuations in resting brain were observed to have a high degree of temporal correlation (P < 10(-3)) within these regions and also with time courses in several other regions that can be associated with motor function. It is concluded that correlation of low frequency fluctuations, which may arise from fluctuations in blood oxygenation or flow, is a manifestation of functional connectivity of the brain.

Partial correlation for functional brain interactivity investigation in functional MRI

“…Similarly, participation of these regions for left-hand movements to the recovery of motor skills has amply been documented in stroke patients Rossini et al, 2003;Ward, 2005) or patients with a tumor or undergoing surgery (Duffau, 2000;Duffau and Capelle, 2001a,b;Krainik et al, 2004), or with multiple sclerosis (Rocca et al, 2005). More recently, studies of functional connectivity, particularly on healthy subjects in resting state (Biswal et al, 1995;Lowe et al, 1998;Xiong et al, 1999) have confirmed that these regions of the motor network are strongly correlated to one another.…”

“…As a result, many methods are available to this end, including activation maps (Huettel et al, 2004), as well as methods deriving from functional connectivity, such as principal or independent component analysis (Friston et al, 1993b;Arfanakis et al, 2000), or correlation maps (Biswal et al, 1995(Biswal et al, , 1997Xiong et al, 1999). In our study, we assume that this step has been successfully completed, providing us with a set of regions and corresponding signals.…”

Strategy‐based reasoning training modulates cortical thickness and resting‐state functional connectivity in adults with chronic traumatic brain injury

“…Advanced neuroimaging techniques using magnetic resonance imaging (MRI) such as morphometry (Ashburner & Friston, 2000; Fischl & Dale, 2000) and resting‐state functional connectivity (rsFC) MRI (Biswal, Yetkin, Haughton, & Hyde, 1995) allow us to identify TBI with better sensitivity and precision. MRI‐based morphometry has revealed altered cortical thickness and volume within individuals who have sustained a TBI (Bendlin et al., 2008; Gale, Baxter, Roundy, & Johnson, 2005; Kim et al., 2008; Sidaros et al., 2009; Spitz et al., 2013; Tate et al., 2014; Turken et al., 2009; Warner et al., 2010; Zhou et al., 2013).…”

Alterations of fronto-temporal connectivity during word encoding in schizophrenia

“…Several specific approaches have been implemented (Horwitz, 2003), and their relative merits have not been established. The timeseries correlation method (Biswal et al, 1995;Lowe et al, 1998) examines interregional correlations within individual subjects over the timecourse of an experiment, and has been effectively applied to measure functional connectivity across a wide range of cognitive and physiological states (Li et al, 2000;Lowe et al, 2002;Greicius et al, 2003;Honey et al, 2003;Anand et al, 2005;Bartels and Zeki, 2005;Fox et al, 2005;Koshino et al, 2005;Menon and Levitin, 2005;Peltier et al, 2005).…”