In a recent study published in the Proceedings of the National Academy of Sciences (PNAS), researchers observed that mindful attention promoted control of brain network dynamics.
Background
Mindfulness is a strategy to direct efforts toward educational, health, and work goals. Enhancing mindful attention can help one notice and discontinue mind-wandering moments and self-referential thoughts. Decreased self-referential processes are associated with suspending neural activity in the default-mode regions, including the medial prefrontal cortex, precuneus, and posterior cingulate cortex (PCC).
As individuals practice mindfulness, the brain might redirect neural activity from the default-mode network to cooperating attention and frontoparietal regions as a non-linear function similar to other learning types. Diverting cognitive resources is consistent with deautomatizing cognitive and emotional reactions that are spontaneous and habitual.
The study and findings
In the present study, researchers investigated the neural dynamics of mindful attention in college students using functional magnetic resonance imaging (fMRI) in the resting state and response to an alcohol cue reactivity task. Seventy-six students were randomly assigned to an experimental group to practice mindful attention or a baseline group to respond naturally exclusively.
Participants in the experimental group were briefly trained to induce mindful attention during an fMRI task. Subjects in the experimental group were instructed to react to alcohol images naturally or mindfully in the fMRI task, whereas those in the baseline group were instructed to respond naturally. The researchers measured self-regulated drinking behavior over four weeks post-scan.
The authors tested four hypotheses linking the stability and effort of neural activity to mindful attention and self-regulation. The first hypothesis was that subjects would moderate alcohol consumption by decreasing the drinking probability if their structural networks provided greater average controllability.
Participants with greater average controllability tended to have a lower drinking probability across both groups. The magnitude of neural response for mindful attention showed a positive correlation with the average controllability of regions in the dorsal attention network and a negative correlation with that of regions in the ventral attention network. The average activity was not different in these networks or the whole brain between groups.
Next, they computed control inputs that dorsal/ventral attention and frontoparietal control sub-networks should exert to transition from the baseline (neural state with no task-related activity) to the task state. The team found that mindful attention decreased craving compared to natural reactions in the experimental group, but the average craving was not different between groups.
The team hypothesized that deautomatizing mindful practice would create neural states requiring more effort. Concordant with the hypothesis, when transitions that occurred with the decreased influence of PCC and precuneus were stimulated, more control input was needed for the transition to mindful attention than for naturally reacting states.
As individuals gained expertise in decreasing the influence of PCC and precuneus, they could transition to a mindful attention state and sustain it with non-linearly declining control inputs. Individuals attending to cues mindfully required more control input when instructed to respond naturally than baseline group participants.
The third hypothesis was that the mindful and natural reaction states of the experimental group would be more unstable than the state of the naturally-reacting baseline group. The neural states of dorsal/ventral attention and frontoparietal control sub-networks were less stable in the experimental group for mindful reactions than for natural reactions.
The natural reactions of the experimental group were also less stable than those of the baseline group. Mindful attention required more control input and was more unstable than natural reactions in the experimental group. Moreover, while mindful attention required more control input on average, individuals required more control input throughout the task to react naturally.
This suggested that natural dynamics become deautomatized during mindful regulation using control inputs. Finally, the researchers investigated whether unstable and effortful neural states in the resting state fMRI were more present-focused across all participants. The fourth hypothesis was that brain regions with higher average controllability and resting-state trajectories with greater instability and effort would have quicker intrinsic timescales.
Regions with greater average controllability tended to have faster decay and more-dissimilar states. Areas that required higher control input to execute resting-state trajectories tended to have faster decaying states and more-dissimilar dynamics. Areas with greater control stability had more-similar dynamics and slower decay. Consonant results were observed analyzing task activity relating faster intrinsic timescales to instability and effort of mindful attention.
Conclusions
To summarize, participants with greater network controllability moderated alcohol consumption. Mindful attention required higher control input and was more unstable than reacting naturally. This increased instability/control input persisted for mindful group members whose natural reactions interspersed with mindful attention, suggesting a learned effort to deautomatize and discontinue habitual reactions.
Brain regions that could steer neural trajectories to new states had quicker intrinsic timescales. Shorter timescales indicate present-focused activity discontinuing the past processing to focalize the present.
Together, the findings suggested that mindful attention supports alcohol consumption regulation by biasing control of neural dynamics that are more deautomatized, discontinuing, and present-focused.