Meditators probably show increased behaviour-monitoring related neural activity

Abstract

Objectives: Mindfulness meditation is associated with better attention function. Performance monitoring and error-processing are important aspects of attention. We investigated whether experienced meditators showed different neural activity related to performance monitoring and error-processing. Previous research has produced inconsistent results. This study used more rigorous analyses and a larger sample to resolve the inconsistencies. Methods: We used electroencephalography (EEG) to measure the error-related negativity (ERN) and error positivity (Pe) following correct and incorrect responses to a Go/Nogo task from 27 experienced meditators and 27 non-meditators. Results: No differences were found in the ERN (all p > 0.05). Meditators showed larger global field potentials (GFP) in the Pe after both correct responses and errors, indicating stronger neural responses (p = 0.0190, FDR-p = 0.152, np2 = 0.0951, BFincl = 2.691). This effect did not pass multiple comparison controls. However, single electrode analysis of the Pe did pass multiple comparison controls (p = 0.002, FDR-p = 0.016, np2 = 0.133, BFincl = 220.659). Meditators also showed a significantly larger Pe GFP for errors only, which would have passed multiple comparison controls, but was not a primary analysis (p = 0.0028, np2 = 0.1493, BF10 = 9.999). Conclusions: Meditation may strengthen neural responses related to performance monitoring (measured by the Pe), but not specifically to error monitoring (although measurements of the Pe after errors may be more sensitive to group differences). However, only the single electrode analysis passed multiple comparison controls, while analysis including all electrodes did not, so this conclusion remains tentative.

Meta-analysis Provides Weak Evidence for an Effect of Mindfulness on Neural Activity Related to Error-Processing in Healthy Individuals Only

“…An effect isolated to Pz might suggest an altered distribution of neural activity (with different brain regions activated in the mindfulness group compared to the control group, an effect we have previously observed: Bailey et al, 2020, Wang et al, 2020 rather than an altered overall amplitude. However, this altered distribution characterization of the effect of mindfulness on the Pe has not been reported in the literature, while an increased overall Pe amplitude has been suggested (Bailey et al, (2022b). Given the paucity of evidence in this analysis and an inability to characterize the overall neural response strength or the distribution of activity within the current meta-analysis, there lies a large gap in our understanding of the effects of long-term mindfulness on Pe amplitude.…”

“…While both studies that reported reduced Pe amplitudes in the mindfulness group used averaged mastoids or linked ears as the referencing montage, and both studies reporting increased Pe amplitudes in the mindfulness group used average referencing montages, re-analysis of data from a combined dataset of Bailey et al (2022b) and referencing to an average of T7 and T8 (very close to the mastoid) provided effect sizes in the same direction as when both studies used the average re-referencing montage. This suggested that the reference montage was not the explanation for the results.…”

“…However, of the studies included in this analysis, only the two studies from our lab reported Pe amplitudes at Pz for a sample of participants who had been meditating for years. Both studies reported negative voltages at Pz during the Pe window, with meditators showing more negative values than controls (a result that was only significant in Bailey et al, 2022b). Additionally, only two studies reported Pe amplitudes from a sample of participants who had been meditating for weeks.…”

“…Pe amplitudes are often reversed in polarity between frontal and parietal electrodes, so to test for the possibility that effects may be present in specific electrodes overlying either parietal or frontal regions, we performed separate analyses restricted to only the studies that reported data specifically from Pz (Bailey et al, , 2022bCragun et al, 2020;Lin et al, 2019;Rodeback et al, 2020;Saunders et al, 2016;and Smart & Segalowitz, 2017) and from FCz (or the average of Fz and Cz) (reported later). The analysis for studies that reported data from Pz showed that the omnibus test of model coefficients was significant Q(2) = 8.023, p = 0.018 (Fig.…”

“…Lastly, we performed an analysis restricted to only the studies that reported data from FCz , Bailey et al, 2022b, Teper & Inzlicht, 2013 or averaged across Fz and Cz, Andreu et al, 2017). These studies also happened to be the studies that only examined longterm meditators in cross-sectional designs; therefore, no between-study factors (such as mindfulness practice time) were included in the analysis.…”