2. What is Mindfulness?
• Defined
– Present-moment awareness and attention to
internal and external experiences
– Focused attention: cognitive practice of sustained
attention on breath
• Psychological and physiological benefits
– Increased well-being, decreased psychopathology
– Better outcomes in stressed patient populations
– Decreased subjective experience of pain
3. Brain Mechanisms Underlying
Mindfulness
• Limbic regions
– Amygdala: functional and structural changes
• Cortical regions
– Top-down modulation of limbic regions
attenuated affective response to stress
• PASL MRI measures CBF
4. Hypotheses
1. Meditation will reduce pain ratings
2. Meditation will modulate activity in brain
regions associated with pain processing
1. PFC, ACC, anterior insula
3. Is meditation-related activation associated
with pain modulation?
8. • Activations and
deactivations pre-
training (vs rest)
• ATB
– Less DMN activation
cognitively
engaged
• Pain-related activity
– Consistent with
previous studies
– Validates
methodology
9. Post-Training Outcome Measures
• After 4 days of meditation training,
mindfulness skills increased (FMI)
• Respiration Rate
– Decreased during meditation in presence of
noxious stimuli
– Decreased in post-training
• Heart Rate
– Greater during noxious stimulation
10. Meditation
• SI nose and
throat
• Interoceptive
attention
• ACC, Insula
• Pain Modulation
• OFC, ventral
striatum, vlPFC
• PCC, mPFC
11. Pain
• Insula
• ACC
• SII
• Similar to pre-
training and
previous studies
•ACC and AI
overlap pain
modulation
12. SI and SMA: interaction between
meditation and noxious stimuli
• SI activation during meditation compared to rest in
the presence of noxious heat stimulation
13. • Right AI and bilateral
ACC
– Greater meditation-
induced activation
greater reductions in pain
intensity ratings
• OFC, thalamus
– Greatest meditation-
induced
activation/deactivation
greater reductions in pain
unpleasantness
14. • Meditation activates self-regulation areas
– Cognitive control: ACC
– Emotion regulation: OFC
– Interoceptive awareness: AI
16. Proposed Mechanisms for Meditation-
Induced Pain Reduction
1) Executive regions SII, insular cortex, PPC
SI
2) ACC and right AI as pain modulatory regions
affected by mindfulness
3) Increased affective regulation and reward
processing by OFC
4) Limbic-thalamic gating mechanism activated
by meditation
17. Take-Home Message
• Mindfulness is among the cognitive
manipulations that can decrease pain perception
– Shares common modulatory pathway with attentional
control, placebo, reducing expectations of pain
• This may occur via changes in signaling between
executive regions and subcortical structures
18. Critique
• Small sample size
• Didn’t account for other individual trait
differences that may influence pain
modulation
• Long-term effects? Is sustained practice
required?
• Relation to structural changes?
Editor's Notes
Lower salivary cortisol, higher salivary IgA in response to psychological stressor
PFC, ACC, and anterior insula attentional control and affective processing
15 healthy adult subjects, 6 male
Psychophysical training session: familiarized subjects w/ visual analog scale, thermal stimuli, MRI stimuli
MRI session 1 (pre-meditation training): 2 blocks of rest (eyes closed) – heat or neutral stimulus. Instructed to start focused attention meditation w/ breath, continued through 2 more blocks of heat/neutral. Pain ratings assessed after each block.
Meditation training: 4 days of training, 20 min/day. Taught to focus on sensations of breathing, acknowledge intrusive thoughts w/o emotional reaction and let them go, redirecting attention back to breath sensations. MRI scanner sounds in days 3 and 4 of training.
MRI session 2, post-meditation training: 4 blocks of rest (2 heat, 2 neutral stimuli), then instructed to begin focused attention meditation, then another 4 blocks of meditation with heat or neutral stimuli. Pain ratings assessed after each block.
No sig diffs in intensity or unpleasantness ratings between rest and ATB conditions pre-training
Sig decreases in both intensity and unpleasantness ratings between rest and meditation conditions post-training
Pain-related increases in brain activity: ACC, bilateral insula, primary and secondary somatosensory cortex, right putamen
Meditation reduces SI activity during noxious heat stimulation
How brain activity relates to pain intensity and pain unpleasantness ratings
Pre-training vs post-training
Executive regions (OFC, ACC, AI) influence pain-related afferent processing in SI via pathways that run through SII, insular cortex, and PPC
ACC and right AI are regions that modulate pain overlap in activity during meditation and pain, plus activity correlates w/ reduced pain intensity ratings
Mindfulness reduces appraisal of negative affective/sensory experiences
OFC activation during meditation OFC regulates affective response, processes reward/hedonic benefits of cognitive regulation of pain pain relief + positive mood induction
OFC activation was associated with reduced unpleasantness ratings in this study
Limbic-thalamic gating mechanism activated by meditation: thalamus deactivation during meditation
PFC projections to thalamic reticular nucleus modulates sensory nuclei of thalamus filters transmission of sensory info (e.g. noxious stimuli) back to cortex