1
Meditative Neuroplasticity: The Effect of Qigong Meditation
on Brain-Derived Neurotrophic Factor and Cortisol Levels.
By
Travis Preston Whitney
A Thesis
In Partial Fulfillment
Of the Requirements for the Degree
Master of Science in Integrative Medicine Research
June, 2015
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Meditative Neuroplasticity: The Effect of Qigong Meditation on
Brain-Derived Neurotrophic Factor and Cortisol Levels.
By
Travis Preston Whitney
Approved by the Master’s Thesis Committee:
______________________________________________________
Melissa Gard, PhD Date
Carolyn Nygaard, ND Date
______________________________________________________
Melanie Henriksen, ND, MSOM, CNM Date
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ABSTRACT
MEDITATIVE NEUROPLASTICITY: THE EFFECT OF QIGONG
MEDITATION ON BRAIN-DERIVED NEUROTROPHIC FACTOR
AND CORTISOL LEVELS.
TRAVIS PRESTON WHITNEY
Introduction: BDNF and cortisol levels are known factors in certain
neurodegenerative diseases such as Parkinson and Alzheimer’s, and in
conditions like obesity and depression. Modalities that affect BDNF and
cortisol levels can have therapeutic and preventative benefits. The primary
purpose of this study is to determine whether meditation affects baseline
BDNF levels or increases BDNF following a meditation intervention when
comparing long-term meditators to non-experienced meditators.
Methods: This pilot study examines the effects of a 30-minute meditation
intervention on BDNF levels and cortisol production in a healthy sample of
experienced meditators (n=7) compared to non-experienced meditators
(n=7). BDNF levels and cortisol will be compared in both groups prior to
and following a 30-minute meditation intervention. A secondary goal of this
study is to determine whether meditation improves cognitive performance,
as measured with a computer application called Lumosity.
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Results: Baseline mean BDNF was slightly higher for the experienced
meditator group (by 0.9 ng/mL), while the mean BDNF post meditation was
slightly higher for the non-experienced meditator group (by 1.2 ng/mL)
Mean cortisol decreased for both groups post meditation. The experienced
meditator group demonstrated higher change in their post meditation scores
on each of the 3 lumosity brain games.
Conclusions: This study provides a first step to determining whether
meditation can increase BDNF and decrease cortisol, thereby providing a
simple, low cost option to increase synaptogenesis in the brain. No change in
BDNF was found between experienced and non-experienced meditators
before or after meditation, but there was a decrease in cortisol in almost all
participants. However due to the low sample size it was difficult to achieve
statistical significance. On average experienced meditators scored higher on
Lumosity Brain Games after meditation compared to non-experienced
meditators. Indicating there may be some mechanism of neuroplasticity
occurring.
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TABLE OF CONTENTS
ABSTRACT ……………………………………………………………… 3
LITERATURE REVIEW ………………………………………………… 6
METHODOLOGY ……………………………………………………….. 16
RESULTS ………………………………………………………………… 27
DISCUSSION …………………………………………………………..... 31
ACKNOWLEDGMENTS ………………………………………………... 38
APPENDICES ……………………………………………………………. 39
REFERENCES …………………………………………………………….52
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LITERATURE REVIEW
Neurodegenerative diseases such as Parkinson’s and Alzheimer’s
affect nearly 6 million individuals, and this number is expected to almost
double by 2030. 1 Depression is another major illness steadily on the rise, as
is the use of antidepressant medications. 2 While finding treatments and
cures are definitely a necessity to battle these illnesses, prevention is key. In
addition, while we live in a busy, fast paced society, many individuals
without major illnesses are looking for ways to increase their cognitive
potential and prevent illnesses as listed above. Perhaps there is a way to
increase an individual’s neuroplastic efficiency while preventing them from
later illnesses. Brain-derived neurotrophic factor (BDNF) and cortisol are
known factors in neurodegenerative diseases such as Parkinson’s and
Alzheimer’s and in conditions like obesity and depression. Therapies that
increase BDNF and lower cortisol would therefore be both therapeutic and
preventative.
BDNF is a contributing factor to increasing cognitive potential and
protecting against neurodegenerative diseases. BDNF promotes survival of
dorsal root ganglion cells. 3 4 Because it shows properties towards
developing the nervous system, it is classified as a neurotrophin. BDNF
stimulates the development and differentiation of new neurons and promotes
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long-term potentiation (LTP), a form of synaptic plasticity, which is still
widely considered a cellular model of long-term memory (LTM) formation.
5 BDNF also promotes neuron survival and is abundantly expressed
throughout the developing and mature CNS as well as in many peripheral
tissues, including muscle, liver, and adipose. 6 This key feature of BDNF
promoting neuronal survival could play a vital role in combating
neurodegenerative diseases. Several researchers have noted that
neurotrophins, such as BDNF, may promote specific neuronal populations
affected in neurodegenerative diseases such as Alzheimer and Parkinson’s. 7–
10 Low levels of BDNF are also associated with insulin resistance, type II
diabetes, and depression.11 12
BDNF is thought to play a role in reinforcing plastic changes in the
brain by consolidating connections between neurons so they fire together in
the future.13 Specifically, when individuals are attempting a new task
requiring specific neurons to fire, BDNF is released. BDNF helps connect
these neurons together and facilitate myelination of the neurons.
Interestingly, BDNF is shown to activate the part of the brain that allows us
to focus attention, the nucleus basalis. BDNF is one of many proteins
necessary for learning and memory, and can slow down normal age-related
cognitive decline. 5,14 BDNFs highest expression can be found in key areas
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responsible for cognitive functions, such as in the hippocampus, neocortex,
cerebellum, and amygdala. 15–17
Because measuring human BDNF directly in the brain would be very
difficult, it is measured from serum, plasma, cerebral spinal fluid (CSF),
saliva, and platelet. Levels of BDNF vary between serum, platelet, or plasma
levels. For instance, Lommatsch et al. found that age, weight, and gender
correlated with plasma BDNF, but there was no significant difference found
between platelet BDNF and these measures.18 Plasma BDNF is more
sensitive but is also more variable than platelet BDNF. When controlled for
age and weight, platelet BDNF levels are significantly different between
men and women.18 Serum levels of BDNF have the advantage of not having
the variability of plasma levels.
Several factors may determine BDNF levels in an individual such as
weight, age, gender, and exercise. BDNF levels have an inverse correlation
with weight; lower levels of BDNF are associated with higher weight. 18,19
Age exhibits a negative correlation on BDNF serum levels but no significant
difference is found in platelet BDNF levels.14,18 Gender differences may
influence BDNF levels, depending on the measurement of BDNF. As
discussed above, Lommatsch et al. observed a difference in platelet BDNF
levels in a weight-matched gender group, but there was no difference in
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plasma BDNF levels.18 Pillai et al. found lower circulating plasma levels in
females 20 while Chan et al. observed no significant difference in serum
BDNF levels between males and females. 14 Gender BDNF levels can be
further complicated with the diurnal pattern of BDNF. Piccinni et al.,
observed a diurnal BDNF pattern in healthy males, but a more stable pattern
in women. 21 Effects of BDNF and gender and sex may not be as big of a
factor on BDNF secretion as physiological changes are. 21
It’s suggested that activities, like exercise, can increase levels of
BDNF, leading to better cognitive performance. A study in rats suggests that
forced and voluntary exercises can enhance cognitive related tasks via the
BDNF pathway. 22 Exposure to an enriched environment and exercise
elevated the levels of BDNF in the hippocampus, increases neurogenesis and
improves learning. 23 In humans, it has been observed that BDNF is
increased by exercise, 24 and there is an increase in memory performance at
higher fitness levels. 25
BDNF is released in an activity-dependent manner 26 and can
modulate the number and shape of dendritic spines in mature hippocampal
neurons, a part on the brain known for memory formation. 4 Structural
changes in dendritic spines is said to lead to synaptic efficacy, the “hallmark
of LTP”. 27 Long-term Meditation (LTM) may serve as an activity-
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dependent BNDF promoter and may have a profound effect on Long-term
Potentiation (LTP).
BDNF has been shown to rise in serum, plasma, and platelet levels
during exercise, immediately following exercise and can remain stable in the
blood for around 1 hour. 28,29 A study in mice has shown BDNF mRNA
expression peaking 2 hours after exercise. 30
Another study demonstrates there may be a genetic polymorphism
that affects BDNF levels.31 Certain BDNF genotypes express different
catecholamine levels than others, showing different responses to stress in
meditators. 31 The effects of BDNF on the stress response leads to the
question of whether other hormones associated with stress effect cognitive
performance and neuroplasticity.
Cortisol, the primary hormone associated with stress, has also been
found to play an important role in learning and memory, having both a
positive and negative effect on cognitive performance. 32 Stress, via an
increase in glucocorticoids such as cortisol, can facilitate hippocampal long-
term potentiation (LTP). 32,33 However too much cortisol can have a
detrimental effect on learning. 34 A slight increase in cortisol will bind to
high-affinity hippocampal receptors and enhance LTP, however long term
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cortisol does the opposite. 33 Prolonged stress can disconnect neural
networks and inhibit neurogenesis. 33
Meditation is most popularly known to decrease stress via lowering
cortisol levels. For instance Walton et al. tested cortisol levels in 16 long-
term transcendental meditators and compared them to 23 age and gender
matched controls. 35 Urinary cortisol was three times higher in the control
group versus women who performed transcendental meditation. 35
Whether people who meditate have increased BDNF levels has not
been studied. However, there is physiological evidence to suggest that this is
true. For example, neuronal growth is promoted by BDNF and inhibited by
excess cortisol. Meditation is known to decrease cortisol.21 Meditation has
also been shown to increase neuronal growth as demonstrated by an
increased cortical thickness observed in experienced meditators. Meditation
may elicit these effects through an increase in BDNF activity. 36
This study explores a different modality for modulating an
individual’s BDNF. Specifically the study explores the role Qigong
meditation might have on BDNF levels. The word Qigong (Sometimes
spelled Chi Kung) is made up of two Chinese words. Qi is pronounced chee
and is usually translated to mean the life force or vital-energy that flows
through all things in the universe. The second word, Gong, pronounced
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gung, means accomplishment, or skill that is cultivated through steady
practice. Together, Qigong (Chi Kung) means cultivating energy, it is a
system practiced for health maintenance, healing and increasing vitality. 37
According to Ken Cohen of the Qigong Research And Practice Center,
Qigong is the art and science of using breathing techniques, gentle
movement, and meditation to cleanse, strengthen, and circulate the life
energy (qi). 38 Qigong is an integration of physical postures, breathing
techniques, and focused intentions. 37 As a meditation, Qigong is a means to
still the mind and enter a state of consciousness that brings serenity, clarity,
and bliss. 39
Meditation has been described as “mental training of attention” 40.
Repeated studies in meditation show that it increases an individual’s
attention span. 40,41 Our sensory systems are barraged with input throughout
the day. Meditation helps an individual focus on selecting goal-relevant
information. 42 Individuals have improved scores on the Attention Network
Test after only five days of 20 minutes of meditation per day when
compared against a control group. 43
Studies show meditation can have a profound effect on brain
structure. Meditators have been shown to have increased cortical thickness,
particularly in areas related to attention, interoception and sensory
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processing such as the prefrontal cortex and right anterior insula. 44–46 When
compared to non-experienced meditators, experienced meditators show
increased cortical thickness in several regions of the brain, including the
medial prefrontal cortex, superior frontal cortex, and temporal pole. 47 In
addition, the meditation experience is associated with increased prefrontal
cortical thickness and increased gray matter density in the brainstem, which
suggests potential effects of meditation on brain plasticity. 44,48 Interestingly,
Brefczynski-Lewis et al. 41 point out that meditators present less activation in
the medial frontal region of the brain during meditation, an area that allows
us to fine tune our cognitive control, such as inhibiting motor actions during
a task if it is identified as incorrect or inappropriate. 40,49,50 This allows
meditators to exert less effort and make fewer adjustments when performing
an action, an attribute well suited for neuroplastic efficiency in learning a
new task.
In the Annals of the New York Academy of Science, Xiong and
Doraiswamy discuss meditations effects on cognition and brain plasticity,
and surmise that meditation may increase growth factor levels, such as
BDNF. 51 Buddhist compassion meditation reduces cortisol secretion and
may potentially enhancing BDNF function. 52,53
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This study will assess memory and attention required in learning a
new task through an online brain-training program. Lumos Labs’ Lumosity
is a web-based platform used to assess and improve users cognitive abilities.
Lumosity has collected the largest data-set of human cognitive performance.
54 Lumosity has been used to measure:
cognitive function in traumatic brain injury survivors;
cognition performance related to life-style factors;
learning ability associated with age; and
cognitive performance in children with cancer-related brain
injury. 54–56
Children with cancer-related brain injury demonstrate significant
improvements in memory and processing scores after administering a
Cognitive Rehabilitation curriculum from Lumos Labs. 56 Sternberg et al.,
show general improvement with Lumosity training while measuring
cognitive tasks and aging, noting learning decreased more with age in tasks
associated with memory than with “crystallized tasks” such as arithmetic
and verbal fluency. 54 Four adult males with severe traumatic brain injury
experienced significant improvements and reached levels of new difficulty
in Lumosity.
This study proposes that experienced meditators will:Meditative Neuroplasticity
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have higher baseline and post-intervention BDNF levels versus
non-experienced meditators,
exhibit lower baseline and post-intervention serum cortisol
levels, and
show higher baseline scores and a greater magnitude in score
differences after intervention on the Lumosity Cognitive
Assessment.
If meditation is associated with higher BDNF and lower cortisol, it suggests
that meditation may lead to neuroplastic changes and may have implications
for neurodegenerative diseases’ and conditions that exhibit low BDNF.
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METHODOLOGY
OVERVIEW AND DESIGN
We conducted a pilot study to examine the role of meditation on
BDNF and cortisol production in healthy individuals. Experienced
meditators (n=7) and non-experienced meditators (n=7) underwent a blood
draw to measure baseline BDNF levels and cortisol levels. Cognitive
performance was measured to determine learning potential. Participants
underwent a Qigong meditation intervention for 30 minutes. Following this
intervention, participants repeated the blood draw and cognitive assessment.
All participants in this study had their cognitive scores assessed via
Lumos Labs Lumosity Brain Games. The participants played 3 games
assessing their working memory and information processing such as Tidal
Treasures, Memory Match, and Speed Match. Both groups, experienced
meditators and non-experienced meditators, performed assessments for a
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baseline measure before going through the intervention. After the
intervention, each group played the same games again to determine if either
group was able to integrate learning the games more efficiently. Baseline
measures were compared between groups to assess possible long-term
effects of meditation. The magnitude of the change between baseline and
post intervention scores assessed the immediate effects of the intervention.
RECRUITMENT & SCREENING
Flyers were posted at Qigong studios, martial arts studios, yoga
studios, local colleges (including NCNM), and on Craigslist. The flyer (See
appendix 1) instructed potential participants to email the student
investigator. The student investigator called participants and screened for
eligibility with the telephone script (See appendix 2). Eligible participants
were scheduled for a study visit. A consent form was emailed to all eligible
participants prior to their visit.
POPULATION
Conditions listed below in the inclusion/exclusion table have been
shown in the literature to have decreased BDNF levels compared to a
healthy population, so these participants were excluded from the study so as
not to confound the impact of meditation and these chronic conditions on the
results. Individuals with COPD or other pulmonary disease may have a
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difficult time continually deep breathing during meditation. For this reason
they were excluded from this study.
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Inclusion Criteria Exclusion Criteria
Ages 18-60
At least 3 years of meditation
practice of 4 or more days a
week in the meditation group.
No meditation in the past 2
years for the non-experienced
meditators group
Willing and able to have blood
drawn
Willing to refrain from
exercise 12 hours before
intervention meeting
Willing and able to complete
all aspects of study
Able to provide consent
Alzheimer’s
Parkinson’s
Schizophrenia
Dementia
Depression
Epilepsy
Diagnosed with depression within past 2
years
Previous use of Lumos Labs Lumosity
COPD or other pulmonary diseases
19
Individuals having previously used Lumosity were previously exposed to the
cognitive performance games used in this study and were
excluded from this study.
INTERVENTION
All study visits took place at the Helfgott Research Institute. Upon
arriving for study visit one, all participants signed informed consent forms
after reviewing them with study personnel. Participants had their blood
drawn under the supervision of a licensed clinician. Participants performed
the cognitive performance test via Lumosity Brain Game and their scores
were recorded after each game, then immediately had their blood drawn
after the games. Participants were asked if they needed a restroom break
before starting the meditation.
After reviewing the meditation instructions, participants went into a
quiet room individually. The student investigator instructed each participant
with meditation instructions (appendix 3) and then quietly left the room
while the participant began the meditation. The participant performed 30
minutes of Qigong meditation as described below. At the end of 30 minutes
a chime sounded to inform the participant that the meditation was over.
After meditation, the participant underwent a post intervention blood draw
and played the same 3 Lumosity Brain Games.
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Intervention:
The meditation script was adapted from the text “The Shaolin
Grandmasters’ Text: History, Philosophy, and Gung Fu of Shaolin Ch’an”
Pg 248 (See appendix 1). The student investigator instructed the participants
on how to perform a seated Qigong meditation. The following script was
given to participants:
“Sit down in a comfortable position with your hands on
your knees, palms down. Close your eyes while pushing
your tongue upwards. Keep your neck and back straight,
and begin to take a few long, slow breaths. As you start
relaxing, inhale through your nose for the count of four,
exhale the breath for the count of four, and then keep your
lungs empty for the count of four. As you become more
relaxed you will move slowly into a deeper meditative
state, your heart rate and breathing rate will slow
accordingly. Focus on your breathing. If your mind
wanders away from your breathing just return to counting
your breaths, inhale through your nose for the count of
four, exhale the breath for the count of four, and then keep
your lungs empty for the count of four.”
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Participants were asked to meditate for 30 minutes. The student
investigator read the script to participants; a timer was set with a 10 second
delay while the student investigator left the room. After the delay a first
chime rang informing the patients 30 minutes had started, after 30 minutes a
second chime rang informing the meditation was over. The written
meditation script was left with participants during meditation. This way they
could refer to the script if they became distracted during their meditation.
OUTCOME MEASURES
Primary Outcome Measures – BDNF and cortisol levels:
A blood draw was completed at baseline and within 5 minutes after the
completion of the meditation intervention. 8.5 mL of blood was collected at
each time point. A total of 17 mL of blood was collected from each
participant. The student investigator conducting the analysis was blinded to
participant sample groups at the Emax Immunoassay System (Promega,
Madison, WI; catalog #G7610), which is an enzyme-linked immunosorbent
assay (ELISA). Cortisol analysis was performed by ZRT Laboratories
(Beaverton, OR).
Secondary Outcome Measure – Cognitive assessment measured with
Lumosity:
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Lumos Labs Lumosity Brain Games: Participants scores were compared to
assess learning performance before and after intervention. In a working
memory game called Tidal Treasures, participants are asked to click on an
object, on the subsequent screens participants must identify objects that they
have not previously clicked on. The game continues until a previously
selected object is selected again. At this point the game ends and a score is
given. The length of this game is typically 5-7 minutes. Another game
assessing memory is titled Memory Match. In Memory Match the
participant is asked to memorize a symbol on the right and use keys to select
if it matches with a symbol on the left of the screen. After selecting a few
right answers the symbol on the left fades away, requiring the participant to
memorize what the symbol was. The game lasts for 45 seconds and at the
end scores are given for total number correct, accuracy, and reaction time. In
a third game measuring information processing called Speed Match,
participants are asked to memorize a card. Using the keyboard the
participant clicks an arrow key to select if the previous card matches the next
or if it doesn't match. The participant has 45 seconds to go through as many
cards as they can. At the end of the game a score is given. It took
participants approximately 10 minutes to complete all 3 games.
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Lumosity scores were compared to pre/post interventions scores
separately from each of the 3 different games the participants performed. We
determined how well participants learned a new task by comparing baseline
scores between groups and the magnitude of changes between groups’
scores.
Participants’ scores were recorded on the Lumosity Data Collection form
(appendix 4)
RANDOMIZATION
This study was not randomized. All participants received the same
intervention.
BLOOD COLLECTION
All blood draws were administered according to NCNM’s protocol for
standard blood draw procedures. Following each blood draw into a serum
separator tube, the tube was inverted and allowed to clot at room
temperature for at least 30 minutes but not more than 2 hours from the time
of draw. Tubes were centrifuged for 10 minutes at 1200xg, and following
centrifugation, serum was divided into 500l aliquots, labeled with the
participant’s ID number, and stored at -80°C until analysis. All tubes and
containers were labeled with a unique participant ID. Blood collection at
each time point consisted of a venous blood draw into a single tube: a
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red/grey top SST Serum Separation Tube (Becton Dickinson, Franklin
Lakes, NJ; catalog #367988). One 8.5ml vial of blood was drawn from each
participant at each blood draw, for a total of 17 mLs for the entire study.
Serum samples were labeled with participant ID’s and analyses of samples
were blinded to participants’ previous meditation experience. Serum samples
were analyzed for BDNF in triplicate for reliability measures.
BDNF ANALYSIS
In order to determine the appropriate storage conditions for
participants’ serum samples, we performed a pilot experiment to determine
whether BDNF degrades during overnight refrigeration. To do this,we
prepared a serial dilution of recombinant BDNF protein that was refrigerated
overnight, and on the day of analysis, we prepared a fresh serial dilution of
BDNF. The fresh and 1-day-old samples were analyzed using the BDNF
Emax Immunoassay System followed by reading the plate at 450nm on a
MAXline microplate reader using Softmax Pro 4.8 software. From this
experiment, we concluded that BDNF was unstable during refrigerated
storage. Therefore, all serum samples were stored at -80°C after collection to
minimize degradation prior to analysis.
In order to determine the appropriate dilution for participants’ serum
samples to fall within the ELISA standard curve, we performed a pilot
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experiment to test several dilutions of serum. BDNF has been shown to
range from 1.9 to 51.5 ng/mL with a median of 22.6 ng/mL in healthy
participants.18 Results of our pilot experiment suggested that a 1:100 serum
dilution was appropriate for measuring BDNF in our serum samples.
BDNF levels pre and post meditation were determined by analyzing
serum samples stored at -80°C for not more than 1 month. Each serum
sample was assayed in triplicate according to manufacturer’s instructions
using the BDNF Emax Immunoassay System followed by reading the plate at
450nm on a MAXline microplate reader using Softmax Pro 4.8 software.
Analysis of samples was blinded to participants’ previous meditation
experience.
DATA MANAGEMENT AND ANALYSIS
Laboratory Methods
Following each ELISA assay, triplicate standard curve absorbance
values were averaged and plotted against each standard curve
concentration. A trendline was fitted to the standard curve points using
Microsoft Excel, and the trendline equation was used to calculate the
BDNF concentration of each sample from the average absorbance value
of the sample. As a measure of goodness of fit, an r-squared value of
>0.996 was attained for all standard curve trendlines. BDNF
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concentrations were multiplied by the dilution factor used in the ELISA
assay to generate the final serum BDNF concentration for each
participant.
Power Calculations
Sample size was determined for mean change in serum BDNF from
before to after meditation among all participants. Based on previous
literature we estimated standard deviation of BDNF at baseline to be
approximately 7ng/mL. 25 Using α=0.05 and a paired T-test design, and
assuming a pre-post correlation of r=0.8, 20 participants were required to
achieve 80% power to detect a mean change of 3ng/mL of BDNF.24,25
Since only 14 participants completed the trial, statistical significance was
unlikely.
Statistical Analysis
Baseline characteristics of each group, including gender, age, weight
and education level were recorded and any significant differences were
noted. Mean BDNF, cortisol, and cognitive performance were compared
between groups at baseline using independent samples T-tests. In case of
non-normal distributions a non-parametric Mann-Whitney test was used.
For analysis of pre-post changes in all outcomes we used a linear mixed
ANOVA with meditation group and time (pre,post) as factors. Significant
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results were followed up with paired T-test for pre-post changes in all
participants and independent T-test comparing pre-post changes between
groups. Comparison of pre-post changes according to the different serum
and plasma measures were compared using a paired T tests. Lumosity
percentages were compared to pre/post intervention scores separately
from each of the 3 different games the participants will perform. The
Lumosity scores were averaged for each separate game for both groups
separately. The participants had their Game 1 scores for working memory
(Tidal Treasures) compared between their pre-meditation score and post
meditation score. This happened for the next two games as well. The
range and median score will be provided for both participant groups. In
order to make comparisons, percentages will be used.
RESULTS
Mean age for non-experienced meditators was 35 years, for meditators it
was 34. Ages ranged from 26 to 51 years. The mean baseline BDNF level in
the non-meditator group was 29.1 (± 5) ng/mL, while the mean baseline
BDNF in experienced meditators was 29.9 (± 6) ng/mL. After meditation
non-experienced meditators showed a mean BDNF level of 30.5 (± 5)
ng/mL and meditators showed a mean BDNF level of 29.3 (± 5) ng/mL.
The mean baseline cortisol level in non-experienced meditators was 10.0 (± Meditative Neuroplasticity
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3) ug/dL compared to 9.8 (± 2) in meditators. Mean cortisol after meditation
in non-experienced meditators was 8.1 (± 3) ug/dL and 8.3 (± 2) ug/dL in
meditators. After meditation, the mean change in Lumosity Game 1 (Tidal
Treasures) score (point difference from pre to post meditation scores) for
non-experienced meditators was 57 points, meditators showed a mean
change of 5,529 points; for Game 2 (Speed Match) mean score for non-
experienced meditators was 200 points and 2,993 points for meditators; for
Game 3 (Memory Match) mean score for non-experienced meditators was
907 points and 2,171 points for meditators (Table 2). There was no
statistically significant difference between experienced and non experienced
meditators’ baseline BDNF (p = 0.783) or cortisol levels (p = 0.864). No
statistically significant difference was observed between groups after
meditation for BDNF (p = 0.661) or cortisol (p = 0.904). There was no
statistically significant difference between change in Lumosity Brain Games
cognitive assessment scores Game 1 (p = 0.380), Game 2 (p = 0.138), or
Game 3 (p = 0.613) from pre to post meditation scores. Pearson correlation
indicates strong positive correlation between BDNF and cortisol before
meditation (p=0.29). A paired samples T-test indicated a statistically
significant reduction in cortisol among all participants after meditation
(n=14, p = 0.001).
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Table 1.
Experienced
Meditators (n=7)
Non-Experienced
Meditators (n=7)
Age (Mean) 33 years 35 years
Gender Male (3)
Female (4)
Male (2)
Female (5)
Average days per
week of meditation 6 0
Average minutes per
meditation session 34 14
Average years of
meditation 13 5
Mean baseline BDNF 29.9 (± 6) ng/mL 29.1 (± 5) ng/mL
Mean BDNF post
meditation 29.3 (± 5) ng/mL 30.5 (± 5) ng/mL
Mean baseline cortisol 9.8 (± 2) ug/dL 10.0 (± 3) ug/dL
Mean cortisol post
meditation 8.3 (± 2) ug/dL 8.1 (± 3) ug/dL
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Table 2. Pre/post meditation Lumosity scores
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DISCUSSION
This study aimed to assess the effects long-term meditation, and the
act of meditation, may have on creating a cognitive environment ripe for
neuronal growth to promote neuroplasticity. As discussed above, BDNF is a
protein responsible for neuron growth and cortisol is a hormone that has
shown to decrease neurons in excess. We took seven experienced meditators
and seven non-experienced meditators and compared their BDNF, cortisol,
and Lumosity Brain Training Game scores to assess if meditation can
facilitate learning a new task. We found no statistically significant evidence
that long-term meditators had higher baseline BDNF levels, a greater
increase in BDNF after meditating, lower pre or post meditation cortisol
levels, or a greater increase in their cognitive brain games scores post
meditation. However, with our small sample size it was not likely we’d find
statistical significance.
To date this has been the first study of its kind. Therefore we have no
comparison of how meditation may affect BDNF and cortisol levels to
promote neuroplastic changes in an individual learning a new task.
Furthermore, we cannot attribute that meditation may increase BDNF levels
significantly enough to therapeutically assist or help prevent
neurodegenerative diseases. We did see interesting trends between groups. Meditative Neuroplasticity
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As a group, meditators Lumosity scores improved over all 3 games
compared to non-experienced meditators after meditation. All but one
participants’ cortisol levels decreased after meditation. Interestingly, on
average the non-meditator group’s BDNF levels increased after meditation,
while the experienced meditators BDNF showed no change. If meditation
does increase the production of BDNF, it may be more likely to be observed
in a population that doesn’t meditate and does not have a consistent surge of
BDNF from doing so, while experienced meditators may have become
accustomed to meditation and may not see as much BDNF production. The
act of meditation is known to increase the ‘focus’ and ‘attention’ areas of the
brain. This could account for the meditators greater average scores on the
Lumosity brain games, since a more consistent practice of meditation may
have exercised these brain areas compared to non-experienced meditators.
There were many challenges and limitations to this study. First and
foremost there was a very small sample size. In addition to a small sample
size, the groups were not as defined as we’d hope. This combination proved
difficult to attribute any change from meditation that we didn’t see. Some of
the non-experienced meditators reported that they used to meditate, or do
sometimes, but they still fit within our inclusion criteria of currently not
meditating more than 2 days a week. Furthermore, many non-experienced
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meditators reported engaging in yoga often, which can be very similar to
meditation. Some of the meditators, while fitting the criteria of currently
meditating for more than 4 days of the week for greater than 3 years,
reported going long periods of not meditating and mostly meditating greater
than 4 days a week. Ideally this study would have liked to have sampled
consistent, experienced meditators and compared them to individuals with
no meditation experience. An accurate participant sample for this pilot study
proved difficult due to financial and time constraints.
The act of a 30-minute mediation may have proved difficult for many
of the non-experienced meditators. It is hard to asses if the non-meditator
group meditated or not, or for how long they may have meditated. The same
could also be true for the experienced meditator group. A 30-minute
consistent meditation is difficult to achieve even with some experience in
meditation. Future studies could have a shorter meditation intervention to
address this concern. In addition, adding meditation physical measures, such
as heart or respiration rates, could help assess if meditation was performed.
Comparing different meditation times among the same participants and
seeing which meditation time affects BDNF levels would be an interesting
study. Another limitation involving the meditation intervention was the use
of a Qigong meditation. If meditation has been shown to increase growth to
Meditative Neuroplasticity
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34
certain brain areas this may be attributed to the meditators’ engaging in the
same meditation consistently. This study asked participants to engage in a
certain meditation, which may not have been consistent with what the
experienced meditators had practiced over the years.
It is difficult for us to know which changes in BDNF and cortisol are
significant for neuronal growth. Although we did see a statistically
significant finding of cortisol lowering from pre to post meditation, this may
be contributed to cortisol’s natural diurnal pattern of declining during that
part of the day. The same could be said for BDNF’s diurnal pattern. There
may have been a ‘ceiling effect’ for how much a participant’s BNDF could
have risen. Baseline serum BDNF levels peak at 8m and steadily decline
until reaching the lowest levels around midnight. 57 So since some of the
participants had levels measured in the morning they may have reached their
peak BDNF production. Even if the act of meditation produced more BDNF
this have been more difficult during this time of day. How do we attribute
changes in BDNF and cortisol levels to neuronal growth? We attempted to
answer this question by having participants learn a new task via introducing
them to a Lumosity game, then post meditation having them repeat the game
and observe if they scored higher and increased BDNF while lowering
cortisol. From this we could perhaps extrapolate neuronal growth occurred.
Meditative Neuroplasticity
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35
Is a 1ng/mL increase in BDNF sufficient for neuronal growth to occur
during brain plasticity? A 10 ng/mL increase? How much cortisol decrease
is sufficient to create a better neuronal environment for neuroplasticity?
These are just a few questions that could be addressed in future studies.
This study did not observe an increase in BDNF after meditation.
While we did not see a higher baseline BDNF in long-term meditators, or an
increase in BDNF from either group, we may still question if meditation has
a therapeutic or preventative role in neurodegeneration. Neurodegenerative
diseases and meditation are complex networks with a multitude of factors
occurring. Meditations ability to lower cortisol levels may be a key player,
lowering and balancing the right cortisol secretion ideal to assist neuron
growth and not inhibit or reverse it. Perhaps meditation increases other
proteins important for nerve growth such as Nerve Growth Factor,
Neurotrophin-3, or Neurotrophin 4/5; these may contribute to long-term
meditators having increased cortical thickness.
Future studies in the area of meditation and neuroplasticity could
benefit from several limitations discussed above. A larger sample size, while
ideal for any study, would be very beneficial in attributing meditations
effects to a greater population. The addition of other biomarkers that
contribute to neuron growth would be beneficial in future studies. There are
Meditative Neuroplasticity
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36
many types of meditation so defining a specific type and focusing on
possible neuron growth or neuroplastic effects would be ideal. Qigong,
Transcendental, or Buddhist compassion meditation may all have different,
or similar, effects on brain chemistry. Furthermore, experienced meditator or
non-experienced meditator participants need to be clearly defined. When
looking at long-term effects of a meditation it would be best to have the
study intervention be the type of meditation practice the meditator is
accustomed to. Other areas for studies could be controlling for confounding
genetic, dietary, and lifestyle influences.
In summary, with this thesis we aimed to explore the possibilities
meditation may have on growing neurons and facilitating a neuronal
environment ideal for learning a new task. Additionally we sought to
examine the role meditation may have as a therapy for neurodegenerative
diseases. Previous research suggests meditation promotes neuron plasticity
in areas of the brain important for cognitive processing. BDNF is a key
player in the growth of new neurons, connecting these and other neurons,
and keeping these connections stable. Cortisol is an important hormone in
cognitive processes. Research has shown excess cortisol to decrease
cognitive performance and even promote neuronal atrophy. This is the first
study to explore meditations effect on BDNF, cortisol, and learning. With
Meditative Neuroplasticity
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previous research showing meditation increasing cortical growth, attention,
and cognition, it is an intriguing and plausible hypothesis that meditation
influences these two chemical cognitive components to play a role in
facilitating plastic changes in the brain.
ACKNOWLEDGEMENTS
The author extends a great thanks to the following individuals:
First and foremost I thank my amazing and supporting family whom I love
and miss very much. Thank you to Helfgott Research Institute for providing
the opportunity and support. To Melissa Gard, PhD for her patience and help
while guiding the author through this study. Agnieszka Z. Bałkowiec, M.D.,
Ph.D. for all her expert advice and time teaching me all she could about
brain-derived neurotrophic factor. Angela Senders, ND, Kim Tippens, ND,
MSAOM, MPH, Carolyn Nygaard, ND, Leslie Fuller, ND for their critiques
and recommendations. Doug Hanes, PhD for his masterful statistical
assistance, Deanne Tibbitts, PhD for her expertise and fun guidance of all
the lab work for this study, and my fellow colleagues for their support and
advice. A huge thanks to Katlyn Mudry for her comical, emotional and
technical support. And, Heather Zwickey, PhD for everything she’s done,
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since naming it all would be too extensive. I’m very grateful and honored to
have the opportunity to work with and learn from all of you.
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APPENDICES
APPENDIX 1
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APPENDIX 2
TELEPHONE SCRIPT
Meditation Study Telephone Screening Script
“Hello, ____________________, my name is ________________________
with the National College of Natural Medicine. I’m calling about the
meditation study. Is this a good time to talk? It should take about ten
minutes.”
▪ Yes (continue)
▪ No (Discuss what time would be convenient for both of you)
“Let me tell you about the study and then if you’re interested, we can go
through a screening over the phone to see if you might be eligible. First,
where did you hear about this study?”
Check only one and describe.
□ Poster/flyer at:
____________________
□ Health
professional:________________
□ Newspaper
ad:____________________
□ Event:_____________________
____
□ Website:____________________ □ Article:____________________
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_____ _____
□ Friend/
relative:____________________
□ Radio:_____________________
____
□ Other:_______________________________________________________
____________
(If at any point the participant does not qualify for this study, ask the
following)
“Would you like to be contacted about other study participation
opportunities?”
□ Yes □ No
“This study will assess whether 30-minutes of meditation results in an
increase in a brain chemical that helps brain cells grow. We are looking for
individuals who have been practicing meditation for at least 4 or more days a
week for 3 years or longer; or have little to no experience with mediation
practice at all.
Meditative Neuroplasticity
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You will be asked to meditate for thirty minutes. You will play a memory
game on a computer and have your scores measured before and after
meditation. Are you willing to do these things?
Yes (continue)
No (give them a chance to ask questions or express disinterest. Thank
them for their time and interest in the study.
As part of the study you will also have your blood drawn, we will draw two
tubes of blood before you meditate and two tubes after you meditate. The
total amount of blood we will draw is about 32 mL. This is about the
equivalent of two tablespoons – less than a full shot glass of blood. Does this
sound ok?
Yes (continue)
No (give them a chance to ask questions or express disinterest. Thank
them for their time and interest in the study.
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The visit lasts about an hour and a half and takes place at the Helfgott
Research Institute located at 2220 SW 1st Ave., Portland, OR. Will you be
able to participate in a visit at this location?”
Yes (continue)
No (give them a chance to ask questions or express disinterest. Thank
them for their time and interest in the study.)
“Do you have experience with mediation?”
Experienced Meditators
“To see if you qualify to be in the experienced meditator group, I need to ask
you a few questions.
To qualify for this study, you must have practiced meditation for at least 4 –
5 days a week for 3 years or longer.
Have you practiced meditation for 3 or more years?”
Yes (Skip ahead to ***)
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No (ask if they would you like to be a participant in the non-
experienced meditator group then see below)
Non-experienced meditators
To qualify for this study, you must have not meditated consistently.
Have you practiced meditation regularly during the last two years? By
regularly, I mean more than two times per week or more.”
Yes (close by thanking them for their time and interest)
No (continue)
I don’t know (If the participant states they have meditated to some
extent or are unsure if they qualify, ask them to describe their
meditation practice)
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Say: “Please tell me about your meditation practice so I can tell if you
qualify for the study.”
_____________________________________________________________
________________
*** “Also to qualify for the study, you must be able to provide informed
consent, be between the ages of 18 years old and 60 years old, and agree to
having your blood drawn. Do you meet these criteria?
Yes (continue)
No (close by thanking them for their time and interest)
“In order to be in the study we need to know a few things about your health.
Is this okay?”
Yes (continue)
No (close by thanking them for their time and interest)
I need to ask you a few questions. The information you provide will be kept
confidential.
Meditative Neuroplasticity
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46
You may be from the National College of Natural Medicine. I want to assure
you that health information obtained from all participants, including
classmates and colleagues at NCNM, will be kept confidential. Every effort
will be made to maintain confidentiality of health information that anyone
discloses during the study.
I am going to read you a list of conditions that will exclude participation in
this study. You DO NOT have to say that you’ve had any of these conditions
specifically. Please wait until I have read the entire list. At the end, I will
ask you if anything on the list pertains to you.
Drug addiction,
Alzheimer’s,
Parkinson’s,
schizophrenia,
dementia,
epilepsy, or
diagnosed with depression within the past 2 years.
COPD or other pulmonary diseases
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Do you have any of these conditions.
Yes (close by thanking them for their time and interest)
No (continue)
“In order to be eligible for the study you must have never used Lumos Labs’
Lumosity Brain Training & Brain Games. Have you used Lumosity before?”
Yes (close by thanking them for their time and interest)
No (continue)
“We do ask that you please refrain from purchasing Lumosity before the
study, as using Lumosity before the study might interfere with the studies’
results.”
“We also ask that you refrain from any exercise within 12 hours of the study
visit. This includes exercises such as running, weight lifting, martial arts,
yoga, or other strenuous activities. ”
“It sounds like you may be eligible for the study, so I can schedule a visit for
you. At the visit we will explain the study in further detail. There will only
be one study visit. The informed consent form and all the study activities
will be explained at this visit. We will email you a copy of the informed Meditative Neuroplasticity
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48
consent form for you to review prior to the study visit. Please do not sign
this form until you’re with us at the study visit. Do you have time to
schedule a visit now?
Appointment scheduled for:
_______________________________________________________
“What is the best number to reach you at?”
__________________________ Home / Work / Cell / Preferred Contact
Number
“Is it OK for me to leave a message if you are unavailable?” Yes / No
“What is your e-mail address?” ____________________________________
“What is your mailing address?
____________________________________
____________________________________
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“The Helfgott Research Institute is located just south of downtown Portland.
There is free parking for the research institute under the building. Study
personnel will meet you in the lobby.”
“Would you like me to email or mail you a map?”
Yes No
“Would you like to be contacted in the future about other study participation
opportunities?”
□ Yes □ No
“Do you have any questions?
Yes (answer question)
No (continue)
“Okay, well thank you very much for your time! We look forward to seeing
you on ___________________________ (day and date) at ______________
(time).”
“Good-bye.”
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Appointment Date: __________________ Time: __________________
Map sent (if desired)
ID Assigned: _____________________
Visit scheduled with clinic:
_______ Room # ___________
_______ Blood draw
Outcome entered on telephone and screening logs
Appointment entered on calendar
Appointment confirmed day before visit
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APPENDIX 3
Meditation Script
To be read to the participants prior to meditating:
“Sit down in a comfortable position with your hands on your knees, palms
down. Close your eyes while pushing your tongue upwards. Keep your neck
and back straight, and begin to take a few long, slow breaths. As you start
relaxing, inhale through your nose for the count of four, exhale the breath for
the count of four, and then keep your lungs empty for the count of four. As
you become more relaxed you will move slowly into a deeper meditative
state, your heart rate and breathing rate will slow accordingly. Focus on your
breathing. If your mind wanders away from your breathing just return to
counting your breaths, inhale through your nose for the count of four, exhale
the breath for the count of four, and then keep your lungs empty for the
count of four.”
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APPENDIX 4
Lumosity Data Collection Form
Time point 1 (Prior to meditation)
Lumosity Game #1 Tidal Treasures: Score _______________________________
Lumosity Game #2 Speed Match: Score _______________________________
Lumosity Game #3 Memory Match: Score ________________________________
Time point 2 (After meditation)
Lumosity Game #1 Tidal Treasures: Score _______________________________
Lumosity Game #2 Speed Match: Score _______________________________
Lumosity Game #3 Memory Match: Score _______________________________
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