Distinguishing confounds from true meditation effects: insights from auditory ERPs
thesisposted on 2022-03-28, 01:26 authored by Lydia J. Barnes
Meditation expertise is associated with improved attention in high-level processes (for example, task switching) and low-level processes (for example, perceptual discrimination). Recent studies provide evidence that meditation affects pre-attentive auditory processing, as measured through auditory event-related potentials (Cahn & Polich, 2009; Delgado-Pastor, Perakakis, Subramanya, Telles, & Vila, 2013). However, meditation effects in these studies are difficult to distinguish from experimental confounds introduced by unequal task requirements in meditation and control conditions, unbalanced condition order, and unmatched lifestyle factors among meditators and non-meditators. The aim of this dissertation is to distinguish between the role of meditation and experimental confounds in a first-time meditation effect, reported in Biedermann et al. (2016): N1 attenuation during first-time meditation, compared to a mind-wandering control condition. Experiment 1 replicated the effect. Experiment 2 tested whether mental state influences on repetition suppression were responsible for the effect. Eliminating the opportunity for mental state-induced differences in shortterm repetition suppression did not eliminate the effect. Experiment 3 tested whether tone-related instructions acted as a mediator of mental control in the meditation and mind-wandering conditions. Matching tone-related instructions for both conditions did not eliminate the effect. Experiment 4 replicated the findings of Experiments 2 and 3. The N1 attenuated during the meditation condition (second condition) in Experiments 1-4, as in Biedermann et al. (2016). In Experiment 5, I reversed the condition order established in Biedermann et al. (2016), so that the meditation condition occurred first. The N1 attenuated during the mind-wandering control condition. Thus, I conclude that N1 attenuation during first-time meditation, compared to a mind-wandering control condition, is an effect of condition order. I discuss critical implications of these findings for the design and interpretation of meditation and pre-attentive auditory processing research.