Methylphenidate modulates interactions of anxiety with cognition

Figures

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  Fig. 1. Schematics of the three predictions underpinning MPH-mediated cognitive enhancement. A MPH-driven increase in the dissociation between the engagement of the FPCN and DMN as reflected by (i) stronger activation of fronto-parietal control network (FPCN) regions (task-positive network), which favors cognitive performance and (ii) steeper deactivation of default mode network (DMN) regions (task-negative network), which prevents interference from irrelevant stimuli such as anxiety-related signals. B MPH-driven redistribution of cognitive resources as indicated by lower resource allocation to the FPCN regions (weaker activation), which evidences greater efficiency of the executive control system. Consequently, more resources are available to process and inhibit anxiety, which might be further reflected by increased activation of the DMN regions. C MPH-driven expansion of overall resources as reflected by stronger activation of both the FPCN regions (i.e., better cognitive performance and inhibition of interference from non-relevant stimuli) and the DMN regions (i.e., processing of anxiety without interfering with cognitive performance).

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  Fig. 2. Schematic of the N-Back working memory (WM) task. A Illustration of the two runs, one starting with a Threat block, and the other with a Safe block. The order of runs was counterbalanced across participants. In addition, participants performed the task in two different contexts, safety (Safe blocks) or threat of electrical shock (Threat blocks). Safe and Threat blocks alternated within each run and were paired with difficulty (i.e., 1-Back or 3-Back task). Each run comprised 8 blocks (45 s each) in total, with 2 blocks per task condition (i.e., 1-Back/Safe, 1-Back/Threat, 3-Back/Safe, 3-Back/Threat). B Illustration of a Safe block (letters surrounded by blue color) of a 1-Back task and a Threat block (letters surrounded by orange color) of a 3-Back task. At the beginning of each block, an instruction screen (8000 ms) notified participants of task load, i.e., 1-Back or 3-Back task. Within each block, 18 letters were sequentially presented for 500 ms at 2000 ms interval. Prior to the experiment, participants were instructed that, during the Safe blocks (letters surrounded by blue color), they would never receive an electrical shock, whereas unpredictable electrical shocks could be…

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  Fig. 3. Interaction effect of Drug, Run, and Condition on WM-related BOLD activation in left precuneus (PCU) and left superior parietal lobule (SPL). Upper panel: Drug by Run by Condition interaction on WM-related BOLD (3-Back vs. 1-Back contrast) recruitment of the A left PCU and B left SPL. Lower panel: Histograms of the parameter estimates extracted from the A left PCU and B left SPL. Linear mixed-effects models were conducted on the parameter estimates with Drug, Run, and Condition as fixed factors, and Subjects as random factor. Sex and Age were included as covariates. Error bars represent mean ± standard error of the mean. Color bar: warm colors represent WM-related BOLD activation in MPH compared to PLA, while cool colors represent WM-related BOLD activation decrease in MPH compared to PLA. Crosshairs depict the location of the voxel with the peak activation for the given cluster. Wholebrain activations are corrected for multiple comparisons using a cluster-based approach with a voxel-wise bi-sided p-value threshold of p < 0.001 and a minimum cluster size of k = 16 (432 μL), which corresponds to a cluster-level alpha of p < 0.05 using NN2 clustering, where clustered voxels can…