Past research has suggested that mindfulness training reduces automaticity while processing socio-emotional stimuli. The present study aimed to analyze how mindfulness practice may reduce the use of prior knowledge during the recognition of emotional facial expressions. Based on a predictive brain model, we hypothesized that mindfulness practice would reduce the top-down processing of low spatial frequency information.
This experiment compared the performance of a mindfulness group (n = 32) and a waitlist control group (n = 30) in an emotional Stroop task before and after an 8-week training course. The emotional Stroop task comprised two emotional facial expressions (joy or anger) topped with a congruent or incongruent word, and was primed by facial expressions filtered in two spatial frequency bands: high spatial frequency (HSF) or low spatial frequency (LSF).
Having measured the reaction time, the results showed a significant interaction between group (mindfulness vs. control) and session (before vs. after training; p = 0.04; R2 = 0.001), irrespective of spatial frequency channels. Breaking down the interaction showed that mindfulness-trained participants responded significantly faster than the controls to any type of information. The interaction Group by Session by Priming was not significant.
These results are in line with research underlining the effects of mindfulness-based interventions on global attentional control. More precisely, the global reduced reaction time did not support lower top-down predictive coding abilities specifically driven by low spatial frequency channels, but indicated a better general sensitivity to the perceptual environment.