fMRI of healthy older adults during Stroop interference

Effect of Cigarette Smoking on Prefrontal Cortical Function in Nondeprived Smokers Performing the Stroop Task

“…Consistent with our hypothesis and relevant literature (Banich et al, 2000;Brown et al, 1999;Langenecker et al, 2004;Taylor et al, 1997;Zysset et al, 2001), both test groups showed larger increases of BOLD signal from rest in the left IFG during the incongruent than during the congruent condition. Neuroimaging studies have indicated that the left IFG mediates inhibition in verbal working memory (Jonides et al, 1998).…”

“…They also exhibit larger differences in the activity in the right FEF between the incongruent and congruent conditions than young adults while they perform the Stroop Task during fMRI (Langenecker et al, 2004), suggesting that aging is associated with reduced functional efficiency of the FEF during performance of the Stroop task. The observed interaction in the present study reflects greater activity in the more difficult condition of smokers only and only in the test block before acute smoking.…”

Flexible cognitive control: Effects of individual differences and brief practice on a complex cognitive task

“…Striatal and insular activations have previously been associated with less prepared and consequently more effortful inhibitory control (Kelly et al, 2004), and additional, compensatory recruitment of the IFG, particularly in the left hemisphere, has also been observed in older adults during the performance of inhibitory tasks, including the GO/NOGO task (Langenecker et al, 2004;Nielson et al, 2002). We observed robust decreases in activation in the left IFG and insula, in association with item repetition over the duration of a single block of trials.…”

“…The left cluster showed an overall performance effect-with greater activation for better performers, while the right cluster showed an interaction, such that better performers maintained a consistent level of activation in this area over the course of a block of trials, while poorer performers showed decreases in activation. Both of these regions showed an overall practice-related decrease in activation over the course of a block of trials, which we have suggested reflects the recruitment of these areas under conditions of more effortful inhibitory control (e.g., Kelly et al, 2004;Langenecker et al, 2004), as occurs early in practice, but less effortful and less neurally demanding accomplishment of inhibitory control as a result of item repetition. Thus, performance effects in these areas reveal that maintaining activity benefited performance overall but not over the course of a block, so that activity decreased generally across the sample, but was slightly higher in the better performers.…”

Neural Mechanisms for Dual-Process Reasoning: Evidence from the Belief-Bias Effect

“…In addition, the reduced lateralization of older adults was not due to reduction of right IFC activity, but due to enhancement of left IFC activity. These results are in line with numerous fMRI findings that showed age-related reduction of hemispheric asymmetry and over-recruitment in prefrontal activity in several tasks (Cabeza et al, 1997(Cabeza et al, , 2002(Cabeza et al, , 2004Langenecker et al, 2004Langenecker et al, , 2007Nielson et al, 2002Nielson et al, , 2004Rajah & McIntosh, 2008;Rympa & D'Esposito, 2000). For example, older adults often show bilateral activation in tasks associated with left-lateralized activity in young adults, such as verbal working memory and semantic processing tasks (Bergerbest et al, 2009;Rajah & McIntosh, 2008;Rympa & D'Esposito, 2000).…”