Research has convincingly shown the positive effects of mindfulness meditation practice on attentional mechanisms. I discussed some of these findings in previous blogs, for instance the evidence that mindfulness practice is linked to improved attentional control, which is also evidenced by neural markers that show improved selective attention as well as improved conflict resolution mechanisms.
While the refinement of attention skills certainly is a central aspect of many forms of meditation training, mindfulness practice should also lead to changes in the way how we relate to arising emotions and affective responses. Thus the question concerning the link between attentional and emotional processes arises. Pursuing this question two recent neuroscientific studies provide some insights into the related neural mechanisms.
In the first study, carried out by researchers at the University of Toronto, the EEG was recorded while participants engaged in the Colour-Word-Naming Task, also called Stroop task, similar to the task described in a previous post. During this task, participants have to indicate the font colour a word is printed in, while ignoring the actual semantics of the word. The critical condition is when the font colour and the semantic of the word are in conflict, for instance: BLUE (requiring the response “red”). Attentional control is required to inhibit the automatic reaction of reading the word. While previous studies focused on how meditators process such stimuli, here researchers focused on the brain activity related to the response – in particular the brain activity when participants made an error. A significant amount of previous research has shown that a brain potential (event-related potential) with negative voltage occurs approximately 100 milliseconds after an error is committed. This error-related negativity (ERN) is known to reflect the efficiency of meta-cognitive processes, the ability to be aware of one’s own cognitive states.
In comparison to non-meditators the meditators (with quite varied meditation practices) made significantly fewer errors in the task, indicating superior attentional control. In line with these behavioural differences, their recorded ERN exhibited higher amplitudes, considered to be an indicator of better meta-cognitive processing. All study participants also completed a questionnaire that assesses their level of mindfulness (the Philadelphia Mindfulness Scale, Cardaciotto et al., 2008), which includes the aspects of present moment awareness and of emotional acceptance. Further statistical analysis (for the nerds: serial multiple mediation analysis using bootstrapping procedures) revealed that emotional acceptance influences the relationship between meditation experience and performance on the Stroop task: the fact that participants with more meditation experience made fewer errors in the Stroop task can to a large extent be explained by their heightened emotional acceptance.
The study thus replicates and confirms existing evidence that meditators tend to exhibit better attentional control processes and extends these findings by analysing the ERN a neurophysiological marker of metacognitive awareness. In addition, the role of emotional acceptance – also in relation to cognitive tasks – is highlighted. The study suggests that even when a purely cognitive task like naming the colour of a word is carried out, emotional components may be involved. It might be that with increasing meditation experience, the cognitive processes of meditators are less affected by their emotional states. I discussed other evidence for this interpretation in a previous post.
In the next post I will discuss a second study into the link between emotion and cognition.