This report discusses the biological bases and psychobiological benefits of meditation and yoga. Meditation involves deep relaxation and internalized attention, while yoga includes physical postures, breathing, and sometimes meditation. Reported benefits include increased flexibility and immune function, as well as improved psychological well-being and decreased blood sugar and cholesterol. Research has explored the effects of these practices on the brain and body, such as changes in hormonal and immunological function associated with stress reduction. Meditation and yoga are also linked to energy metabolism, mitochondrial function, and insulin secretion.

1. Branch 1
Innocence Branch
Dr. Jamie L. Reed
Biological Bases of Meditation and Yoga Therapy Supplemental Report
November 25, 2014

2. Branch 1
Abstract
This purpose of this report is to discuss the current reported scientific psychobiological
benefits of meditation and yoga. Meditation is a specific state of consciousness characterized by
deep relaxation and internalized attention. Yoga therapy traditionally involves physical postures,
breathing techniques, and meditation or relaxation techniques. Chief among these suspected ben-
efits are increased flexibility, strength, and balance; enhanced immune function; improved psy-
chological well-being; and decreased blood sugar and cholesterol levels. Meditation and yoga
therapy practices have been investigated by modern science for years in order to explore their
many potential beneficial effects, yet here has been limited understanding of the overall biologi-
cal mechanism of these practices in terms of the effects in both the brain and body. Some re-
searchers have narrowed their scope to investigating changes in hormonal and immunological
function associated with biological bases of yoga and meditation as a therapeutic means of stress
reduction. Additionally, meditation and yoga therapy have linked to energy metabolism, mito-
chondrial function, and insulin secretion.
Processes involved in meditation
My research suggested that meditation might also be expected to alter activity in the limbic
system, especially since stimulation of limbic structures concerning emotional regulation. Other
biological bases involved in meditation and yoga therapy include neuropsychological mecha-
nisms, autonomic activation, and emotional regulation. Some of the supposed psychological ef-
fects of these therapeutic practices are motor and perceptual changes. Investigators have hypoth-
esized that yoga-based practices correct under-activity of the primary nervous system (PNS) and
GABA systems in part through stimulation of the vagus nerves (the main peripheral pathway of

3. Branch 1
the PNS In conjunction). These practices are believed to increase activation of the primary ner-
vous system and lead to mental relaxation. According to more recent studies, meditation has been
adopted by many psychodynamic programs due to reported beneficial effects with a number of
functional somatic, psychiatric, and stress-correlated symptoms (Baer, 2003).
Neurobiological Modulation and Regulation
Since both emotional regulation and spatial attention play an important role in emotion
regulation, meditative therapy practices may have beneficial effects on emotion regulation also.
The ability of the hippocampus to stimulate or inhibit neuronal activity in other structures likely
relies upon the glutamate and GABA systems. The hippocampus acts to modulate and moderate
cortical arousal and responsiveness via rich and extensive interconnections with the prefrontal
cortex, other neocortical areas, the amygdala, and the hypothalamus. Meditation and yoga thera-
py is an apperceptive process that induces a set of integrated physiological changes termed the
relaxation response.
The therapeutic basis of yoga and meditation is credited to the individual calming their
mind during the mindfulness and selective, focused attention which requires one to concentrate
on breathing and relaxing in a quiet state all help to reduce feelings of stress. Activation of the
autonomic nervous system can result in intense stimulation of structures in the lateral hy-
pothalamus and median forebrain bundle, which are known to produce both ecstatic and blissful
feelings when directly stimulated. During meditation, activity in the frontal and parietal lobe
slows down. Researchers suggest that meditation involves the neuropsychological mechanism of
activation of the autonomic nervous system (ANS). The parasympathetic nervous system (PNS)
is a biological function of autonomic nervous system.

4. Branch 1
The frontal lobe is (the most highly evolved part of the brain which is responsible for rea-
soning, planning, emotions and self-conscious awareness) highly engaged during yoga and medi-
tation during certain phases. Yoga puts an emphasis on connecting movements to the flow of
breath within the body and many yoga practitioners use meditation as a medium for centering
their thoughts. The longer an individual’s meditation practice continues, the greater their contin-
ued activity in the prefrontal cortex associated with their persistent will be to focus their atten-
tion. Activation of the parasympathetic system will cause a reduction in heart rate and respiratory
rate.
Biological Substrates
The physiological effects that have been observed during meditative states seem to outline
a consistent pattern of changes involving certain key cerebral structures in conjunction with au-
tonomic and hormonal changes. The parasympathetic system controls the function of the heart,
liver, intestines, and other internal organs. Prior studies have shown indicated predominant
parasympathetic activity during meditation associated with decreased heart rate and blood pres-
sure, decreased respiratory rate, and decreased oxygen metabolism. As an individual experiences
stress, their muscles tense, the heart rate increase, and breathing patterns change while the body
secretes more hormones increasing blood sugar levels and blood pressure (if the stress is allowed
to continue).
It seems salient that a model for meditation begin with vivication of the prefrontal cortex
meditation. This is particularly relevant of the right hemisphere as well as the cingulate gyrus
because meditation requires such intense focused attention. However, further investigations have
also revealed that prefrontal and cingulate activation may be associated with the volitional as-

5. Branch 1
pects of meditation. The cingulate gyrus is credited in focusing attention involvement, possibly
in tandem with the prefrontal cortex.
The lateral posterior nucleus of the thalamus provides the posterior superior parietal lobule
with the sensory information it needs to determine the body’s spatial orientation (Grossman,
Niemann, Schmidt, & Walach, 2004). During meditation, activity in the frontal and parietal lobe
slows down and blood flow that was diverted away from the intestines and reproductive organs
(this function is not essential in an emergency) returns. The levels of free synaptic glutamate
produced in the brain increases in conjunction with increased prefrontal cortex activity. Increased
glutamate can stimulate the hypothalamic arcuate nucleus to release endorphins.
Neurobiological Results
According the aforementioned research on brain imaging, results have suggested that will-
ful acts and tasks which require focused, sustained attention are initiated via activity in the pre-
frontal cortex; particularly in the right hemisphere. Some studies have shown that the prefrontal
cortex excites the reticular nucleus of the thalamus when activated. This is credited as part of a
more global attentional network. There is a adjuvant increase in the activity in the reticular nu-
cleus of the thalamus due to the increased activity in the right hemisphere of this region during
meditation. Prior neurobiological research has demonstrated an increase in serum GABA during
meditation. The functional deafferentation related to increased GABA would mean that fewer
distracting outside stimuli would arrive at the visual cortex and posterior superior parietal lobule
thereby enhancing the sense of focus.
According to Lutz, the practice of meditative techniques was hypothesized to induce
changes in the neural networks that underlie affective processing (Lutz, Brefczynski-Lewis,

6. Branch 1
Johnston, & Davidson, 2008). The lateral prefrontal cortex is involved in modulating emotional
responses. This neurological mechanism has two branches that work in conjunction to help regu-
late the body’s psycho-sociological responses to stress and the environment. The first of these is
known as the sympathetic nervous system and second branch is known as the parasympathetic
nervous system. The flow of sensory data to the thalamus is reduced during meditation and yoga
according to research. In addition, the arousal signal for the reticular formation is reduced during
the meditative process.
The posterior superior parietal lobule is heavily involved in the analysis and integration of
higher-order visual, auditory, and somatosensory information. The effects of meditation and yoga
therapy are likely to be more selective, appearing to alter the perception of the self. Some theo-
rists have propose that deafferentation of these orienting areas of the brain is an important con-
cept in the physiology of meditation. An individual would lose his or her usual ability to spatially
define the self and help to orient the self if deafferentation of the posterior superior parietal lob-
ule were to occur. These physiological responses have all been observed during meditation.
Conclusion:
Both meditation and yoga are reported to be clinically effective for physiological, psycho-
logical benefits, and biochemical benefits. Meditation and yoga therapy are apperceptive pro-
cesses that induce a set of integrated physiological changes termed the relaxation response. They
have adapted by several professional practices including the medical and psychological commu-
nities to assist with decreased anxiety, stress management and improved mental acuity due to
these reported benefits.

7. Branch 1
References
Anantharaman, V., and Sarada Subrahmanyam. Physiological benefits in hatha yoga training.
The Yoga Review, 3(1):9-24.
Baer,R.A.(2003).Mindfulnesstrainingasaclinicalintervention:A conceptual and empirical review.
Clinical Psychology: Science and Practice, 10, 125–143.
Baer, R.A., Smith, G.T., & Allen, K.B. (2004). Assessment of mind- fulness by self-report. As-
sessment, 11, 191–206.
Baer, R.A., Smith, G.T., Hopkins, J., Krietemeyer, J., & Toney, L. (2006). Using self-report as-
sessment methods to explore facets of mindfulness. Assessment, 13, 27–45.
Brefczynski-Lewis, J.A., Lutz, A., Schaefer, H.S., Levinson., D.B., & Davidson, R.J. (2007).
Neural correlates of attentional expertise in long-term meditation practitioners. Proceed-
ings of the National Academy of Sciences USA, 104, 11483-11488.
Grossman, P., Niemann, L., Schmidt, S., & Walach, H. (2004). Mindfulness-based stress reduc-
tion and health benefits. A meta- analysis. Journal of Psychosomatic Research, 57, 35–43.
Lutz, A., Slagter, H.A., Dunne, J.D., & Davidson, R.J. (2008). Attention regulation and monitor-
ing in meditation. Trends in Cognitive Sciences, 12, 163- 169.