Task-dependent organization of brain regions active during rest

Abstract

The human brain demonstrates complex yet systematic patterns of neural activity at rest. We examined whether functional connectivity among those brain regions typically active during rest depends on ongoing and recent task demands and individual differences. We probed the temporal coordination among these regions during periods of language comprehension and during the rest periods that followed comprehension. Our findings show that the topography of this ''rest network'' varies with exogenous processing demands. The network encompassed more highly interconnected regions during rest than during listening, but also when listening to unsurprising vs. surprising information. Furthermore, connectivity patterns during rest varied as a function of recent listening experience. Individual variability in connectivity strength was associated with cognitive function: more attentive comprehenders demonstrated weaker connectivity during language comprehension, and a greater differentiation between connectivity during comprehension and rest. The regions we examined have generally been thought to form an invariant physiological and functional network whose activity reflects spontaneous cognitive processes. Our findings suggest that their function extends beyond the mediation of unconstrained thought, and that they play an important role in higher-level cognitive function.connectivity ͉ default mode ͉ individual differences ͉ stochastic ͉ fMRI

Short- and Long-Term Effects of a Novel on Connectivity in the Brain

“…Short-term effects might be observed immediately after reading. For example, RSNs are known to be altered by recent language comprehension tasks (Hasson et al, 2009) as well as visual categorization tasks (Stevens et al, 2010). Although the chapter readings were performed during the evenings before scans, the quizzes occurred just before the scan.…”

“…Some changes appear to be due to transient activation of specific regions, which persists for minutes to hours (Hasson et al, 2009); while others may persist for longer periods of time and may represent cortical reorganization (Mackey et al, 2013). A limitation of these studies that makes it difficult to determine what are short-and long-term changes is the small number of resting-state scans actually performed.…”

“…Cognitive and emotional interventions have been demonstrated to cause transient changes in functional connectivity (Harrison et al, 2008;Hasson et al, 2009;Mackey et al, 2013;Stevens et al, 2010), but it is not known how long these changes last. Some changes appear to be due to transient activation of specific regions, which persists for minutes to hours (Hasson et al, 2009); while others may persist for longer periods of time and may represent cortical reorganization (Mackey et al, 2013).…”

Does the salience network play a cardinal role in psychosis? An emerging hypothesis of insular dysfunction

“…[90][91][92][93] With its unique role as a switch between these 2 networks, the salience network is crucially positioned to not only enable the behavioural response, but also to consolidate or update prediction models subsequent to stimulus evaluation. In complex social situations, an update of prediction models could involve attitudinal changes.…”

The Effects of Sustained Cognitive Task Performance on Subsequent Resting State Functional Connectivity in Healthy Young and Middle-Aged Male Schoolteachers

“…Although RSNs have been shown to be consistent across individuals and measurements (Damoiseaux et al, 2006), previous studies have reported that task performance can shape subsequent RS FC in both the default mode and task-positive networks (Albert et al, 2009;Hasson et al, 2009;Lewis et al, 2009;Northoff et al, 2010;Stevens et al, 2010;Tambini et al, 2010;Waites et al, 2005). For example, Waites et al (2005) investigated the effect of performing a language task on subsequent RS FC within four language-related brain networks.…”