Brain Mechanisms Supporting
the Modulation of Pain by
Mindfulness Meditation
By: Zeidan, Martucci,
Kraft, Gordon, McHaffie,
and Coghill
“Mindfulness is a state of present awareness. A
relaxed state of mind, in which we are conscious
of our experience, including sensations,
thoughts and feelings, breathing, and
surroundings, all with an attitude of nonresistance, peace and acceptance. This does not
imply passivity or lack of emotion. Mindfulness
engenders faith in the perfection of the moment,
and allows each new experience to be felt fully,
without the reactive, self-critical, controlling
mind.”
• Meditation is not a religion but simply a method of
mental training
•You don’t have to sit cross legged on the floor.. You
can meditate anywhere
•Patience and persistence are required but the
practice of meditation does not take a long time
•Meditation is not complicated, nor is it about
success or failure
•It will not deaden your mind or turn your into a
“hippie” but rather it helps cultivate a deep and
compassionate awareness that allows you to assess
your goals and find the optimum path towards
realizing your deepest values
Introduction
• Our perception of the sensory environment is shaped
by our own unique past experiences, current cognitive
state, and future expectations.
• Best example of this is the subjective experience of
pain- while noxious stimuli initiates physiological and
neurophysiological changes within our bodies, its
effects are highly malleable and subject to
modification.
• The nature of our mental activity can be manipulated
through the practice of mindfulness meditation.
• Shamatha (focused attention) is a form of
mindfulness meditation used in this study.
•Focused attention is the cognitive practice of
sustaining attention on the changing
sensations of the breath, monitoring changing
events as they arise, disengaging from these
events without affective reaction and
redirecting attention back to the breath.
• This allows you to observe your thoughts as
they arise in your mind and little by little, to
let go of struggling with them.
• The authors believed that given that mindfulness
meditation can reduce the subjective experience of pain,
brain regions involved in meditation must somehow
interact with those involved with nociceptive processing
•The specific brain mechanisms associated with
mindfulness meditation were poorly characterized
•How the brain mechanisms could potentially
influence pain related brain activity was unknown
• Therefore the authors investigated how meditation
affects pain related brain processes using an emerging
functional magnetic resonance imaging technique (FMRI)
and pulsed arterial spin labeled (PASL) MRI
THE STUDY:
• Hypothesized that in addition to reducing
psychophysical pain ratings, meditation would
modulate brain regions associated with constructing
the pain experience.
•Specifically that meditation would engage brain
regions such as the prefrontal cortex, anterior
cingulate cortex, and the anterior insula which are
known for their role in attentional control and
affective processing.
• They further sought to determine whether
meditation related activation of these brain regions
was directly associated with pain modulation.
Materials and Methods:
• Fifteen healthy volunteers, six males and nine
females(age range 22-35) completed the study.
•Subjects participated in a psychophysical training
session- initially familiarizing them with 32 5 second
duration stimuli (35-49 degrees C/95- 120.2 degrees F)
to provide experience with the visual analog scales
(VAS). They then received 5 min and 55 seconds of
stimulation. A 15 cm plastic sliding VAS scale was used to
quantify pain intensity and unpleasantness. The
minimum rating was represented as “no pain
sensation/not at all unpleasant” whereas the maximum
was “most intense imaginable/most unpleasant
imaginable”
•MRI session 1: Subjects were positioned in the MRI scanner, a
pulse oximeter was attached to a subjects left index finger to
assess heart rate and a transducer was placed around the chest
to gauge respiration rate. Noxious thermal stimuli were delivered
to the right calf. The heat condition consisted of alternating
patterns of 49 and 35 degrees C with 12 second durations at each
temperature for 5 mins and 55 seconds total. The neutral series
consisted of only 35 degrees C for 5 mins and 55 seconds.
•After each series, subjects evaluation of pain intensity and
unpleasantness was acquired with the VAS scale.
•In this session four functional series (two heat, two neutral) were
separated by a structural acquisition scan. In the first half of the
experiment, subjects were instructed to keep their eyes closed
and restrict movement (rest). After the image was obtained, they
were instructed to meditate by focusing on breathing (ATB)
Mindfulness based mental training:
•Mindfulness based mental training was performed in
four separate, 20 minute sessions conducted by a
facilitator with over 10 years of experience
•Subjects were taught to focus on the changing
sensations of the breath. They were also taught that
discursive thoughts were to be acknowledged without
affective reaction and to let go by redirecting their
focus back on breath sensations.
•In sessions 3 and 4, sounds of the MRI scanner were
introduced to the subjects to familiarize them with the
MRI environment
MRI session 2:
• Occurred after successful completion of
meditation training
•Session consisted of eight function series (four
heat, four neutral).
•After completion of the first four rest series (reduce
eye movement and close eyes) subjects were again
instructed to meditate by focusing on the changing
sensations of the breath at which point the
anatomical scan was conducted. Subjects continued
to meditate across blocks of noxious stimulation and
pain ratings were again assessed after each block.
Results
Before meditation training:
•There was no change in pain intensity when subjects
attended to their breathing
•There was no significantly greater brain activation when
focusing on breath as contrasted to the rest condition,
however there was significantly greater default-moderelated brain activation (medial PFC )in the rest condition
compared with the ATB condition suggesting they were
actively engaged in a cognitive task when instructed to focus
on breath sensations
• When compared with neutral stimulation, pain related brain
activity was detected in the ACC, bilateral insula, secondary
Somatasensory cortex (SII) and SI corresponding to the
noxious thermal stimulation on the leg
Post meditation training/MRI 2:
• Meditation produced a 40% reduction in VAS pain
intensity ratings compared with rest. Pain intensity ratings
were lower in MRI session 2 compared with MRI session 1.
Meditation also significantly reduced pain unpleasantness
ratings by 57%
Meditation related brain activity:
•Meditating produced bilateral activation of the posterior
insula, secondary somatosensory cortex (SII), anterior
insula, and the anterior cingulate cortex which are
associated with the cognitive modulation of pain (these
areas were also activated when compared with neutral
stimulation)
• Somatosensory cortex activation corresponding to the
stimulation site significantly decreased during mediation when
compared with rest
• Individuals with the greatest reductions in pain intensity
ratings exhibited the largest meditation induced activation of
the right anterior insula and bilateral anterior cingulate cortex
•Individuals with the greatest reductions in pain
unpleasantness ratings exhibited the greatest activation of the
orbitofrontal cortex and the greatest deactivation of the
thalamus
•After meditation training, brain activity was more pronounced
in the frontal pole, thalamus, medial prefrontal cortex, and the
anterior cingulate cortex compared with before training
Discussion:
• In the present investigation, meditation reduced all
subject’s pain intensity and unpleasantness ratings
with decreases ranging from 11 to 70% and 20 to 93%
respectively.
•Meditation related pain relief was directly related to
brain regions associated with the cognitive
modulation of pain providing unique insights into the
manner that mediation alters the subjective
experience of pain.
Meditation reduces pain through multiple brain
mechanisms
1) Significantly reduced pain related afferent
processing in the somatosensory cortex
2) The magnitude of decreased pain intensity ratings
was associated with anterior cingulate cortex and
right anterior insula activation
3) Orbitofrontal cortex activation was associated with
decreases in pain unpleasantness ratings- may
reflect altered executive level reappraisals to
consciously process reward and hedonic
experiences (meditation directly improves mood
and positive mood reduces pain ratings)