Functional modular architecture underlying attentional control in aging

Abstract

Previous research suggests that age-related differences in attention reflect the interaction of top-down and bottom-up processes, but the cognitive and neural mechanisms underlying this interaction remain an active area of research. Here, within a sample of community-dwelling adults 19–78 years of age, we used diffusion reaction time (RT) modeling and multivariate functional connectivity to investigate the behavioral components and whole-brain functional networks, respectively, underlying bottom-up and top-down attentional processes during conjunction visual search. During functional MRI scanning, participants completed a conjunction visual search task in which each display contained one item that was larger than the other items (i.e., a size singleton) but was not informative regarding target identity. This design allowed us to examine in the RT components and functional network measures the influence of (a) additional bottom-up guidance when the target served as the size singleton, relative to when the distractor served as the size singleton (i.e., size singleton effect) and (b) top-down processes during target detection (i.e., target detection effect; target present vs. absent trials). We found that the size singleton effect (i.e., increased bottom-up guidance) was associated with RT components related to decision and nondecision processes, but these effects did not vary with age. Also, a modularity analysis revealed that frontoparietal module connectivity was important for both the size singleton and target detection effects, but this module became central to the networks through different mechanisms for each effect. Lastly, participants 42 years of age and older, in service of the target detection effect, relied more on between-frontoparietal module connections. Our results further elucidate mechanisms through which frontoparietal regions support attentional control and how these mechanisms vary in relation to adult age.

Response-level processing during visual feature search: Effects of frontoparietal activation and adult age

“…An age-related decline in the rate of evidence accumulation in decisional processes (drift rate, v) has also been reported, though it is more task-dependent (Madden et al, 2009;Spaniol, Madden, & Voss, 2006;Yang, Bender, & Raz, 2015). Cautiousness, as reflected in the boundary separation parameter (a), also tends to increase with age (Ratcliff, 2008), though again with exceptions (Monge et al, 2017). Neuroimaging studies have found that age-related slowing of drift rate is associated with task-related frontoparietal activation and connectivity (Madden et al, 2010;Monge et al, 2017), but these previous studies did not isolate response-level processes.…”

“…Cautiousness, as reflected in the boundary separation parameter (a), also tends to increase with age (Ratcliff, 2008), though again with exceptions (Monge et al, 2017). Neuroimaging studies have found that age-related slowing of drift rate is associated with task-related frontoparietal activation and connectivity (Madden et al, 2010;Monge et al, 2017), but these previous studies did not isolate response-level processes.…”

“…Older adults have, in some instances, however, exhibited increased task-related activation, particularly in dorsolateral prefrontal regions, which may be a compensatory mechanism to support task performance (Davis, Dennis, Daselaar, Fleck, & Cabeza, 2008;Spreng, Wojtowicz, & Grady, 2010). In the context of conjunction search, aging is associated with an enhancement of functional connectivity between regions (Geerligs, Saliasi, Maurits, Renken, & Lorist, 2014), and enhancement of the relation between neural activation and performance (Madden, Parks, Tallman, Boylan, Hoagey, Cocjin, Johnson, et al, 2017a;Monge et al, 2017).…”

Abnormal degree centrality in chronic users of codeine-containing cough syrups: A resting-state functional magnetic resonance imaging study

“…In addition, we also found decreased degree values in the left inferior parietal lobule and left middle temporal gyrus were related to the cognitive function in the CCS-dependent individuals. A previous study demonstrated that the left inferior parietal lobule, one of the crucial brain regions of the attentional control network, was involved in executive function ( Monge et al, 2017 ). The current results suggested that such abnormal intrinsic connectivity may indicate cognitive and executive deficits in CCS-dependent individuals.…”

Markers of cognitive function in individuals with metabolic disease: Morquio syndrome and tyrosinemia type III

“…When a non-spatial working memory task must be completed at the same time as visual search, search slows but search efficiency is unchanged (Oh & Kim, 2004;Woodman, Vogel, & Luck, 2001). Older adults also show slower search times, without increased display-size effects (Gorman & Fisher, 1998;Monge et al, 2017; see also Ratcliff, Thapar, & McKoon, 2006 for a similar increment in a discrimination task that is attributed to "nondecision" aspects of the task). Reduced capacity could be a factor in common between aging and dual tasking and may also explain our results, but note that this cannot be the same as general slowing since in MPS-IVa both simple RT and saccade onset times were either unaffected (saccade onset time) or only weakly affected (simple RT).…”