Breathing above the brainstem: Volitional control and attentional modulation in humans
Whereas the neurophysiology
of respiration has traditionally focused on automatic brain stem
processes, higher brain mechanisms underlying the cognitive aspects
of breathing are gaining increasing interest. Therapeutic techniques
have used conscious control and awareness of breathing for millennia
with little understanding of the mechanisms underlying their efficacy.
Using direct intracranial recordings in humans, we correlated cortical
and limbic neuronal activity as measured by the intracranial electroencephalogram
(iEEG) with the breathing cycle. We show this to be
the direct result of neuronal activity, as demonstrated by both the
specificity of the finding to the cortical gray matter and the tracking of
breath by the gamma-band (40 –150 Hz) envelope in these structures.
We extend prior observations by showing the iEEG signal to track the
breathing cycle across a widespread network of cortical and limbic
structures. We further demonstrate a sensitivity of this tracking to
cognitive factors by using tasks adapted from cognitive behavioral
therapy and meditative practice. Specifically, volitional control and
awareness of breathing engage distinct but overlapping brain circuits.
During volitionally paced breathing, iEEG-breath coherence increases
in a frontotemporal-insular network, and during attention to breathing,
we demonstrate increased coherence in the anterior cingulate, premotor,
insular, and hippocampal cortices. Our findings suggest that
breathing can act as an organizing hierarchical principle for neuronal
oscillations throughout the brain and detail mechanisms of how
cognitive factors impact otherwise automatic neuronal processes during
Cerf, Moran and Ashesh Mehta. 2018. Breathing above the brainstem: Volitional control and attentional modulation in humans. journal of neurophysiology. 119: 145-149.