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M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 1
Meditation, Neuroplasticity, and Potential for Treatment Interventions
A brief history of the meditative practices,
their effects on neuroplasticity, and their potential as a treatment
intervention for an assortment of mental illnesses.
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 2
AbstractThe thrust of this paper is to provide a comprehensive review of meditative and mindful
practices and their effect on cognitive functioning and neuroplasticity. An additional drive of this
work is to assess the practical applications of these techniques, and have a look at the potential
for use as a treatment intervention for a wide variety of mental illnesses. There were a mix of
systematic reviews, case studies, and control trials that made up the body of evidence going into
this work. Subjects in the studies varied from children to the elderly. Some limitations with the
research are the wide variety of practices that exist, as well as the researcher’s ability to induce
proper meditative states on subjects. The evidence collected strongly correlates regional
alterations – in hippocampal, brainstem, and frontal regions to name a few – with meditative and
mindful practices. Furthermore, increases in grey matter concentration, white matter
concentration, and cortical thickness were all documented. The application of these techniques as
a treatment intervention yielded very promising results. Meditation and mindfulness based
practices displayed statistically significant markers of improvement in anxiety disorders, post-
traumatic stress disorder, schizophrenia, psychosis, depression, and obsessive-compulsive
disorder. More research needs to be done, and the practices need be standardized for clinical use,
however the current evidence suggests these ancient practices are of extreme value to the
treatment of mental health.
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 3
Introduction
Meditation is a spiritual and healing practice that developed on the Eastern side of the
globe. It has quite a rich and intricate history, as it has been traced back further than 5000 years
ago 1. The word meditation – like many English words – is rooted in Latin, and is literally
understood to be the act of engaging in reflection or contemplation 1. A collection of ancient and
traditional texts that were extracted from India known as the “Yoga Sutras”, act as guidelines for
living a meaningful and purposeful life 1. Embedded in these ancient texts are descriptions of
meditative practices, in which they attempt a rough description of it, calling meditation both an
inward reflection and a midpoint of a light focus and a total absorption within something 1.
Meditation is quite a broad term however, as it refers to an assortment of practices that may
range from relaxation techniques to exercises performed 2. For the purpose of clarification, this
work is inclusive of all mind-body exercise that incorporate both dynamic and static components
as well as union of breath and body awareness 13. A few examples of these exercises are
transcendental meditation, mindfulness training, Qigong, Tai Chi, guided imagery, and so on 13.
Therefore, when one refers to the term meditation they may be referring to this assortment of
practices, as any one of them apply a selection of emotional and attentional monitoring
approaches that are in theory utilized for ends such as developing well-being and optimizing
emotional balance 2.
While all variations of meditation are intended to enhance the capacity to be mindful, the
Buddhist traditions place a particular emphasis on cultivating mindfulness. For this reason, these
traditions have served as the primary source for the many and varied mindfulness techniques
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 4
now incorporated into Western psychotherapeutic practices 4. Despite the simplicity with which
meditation appears to convey, it actually involves a high degree of cognitive functioning as it is a
multi-faceted task that relies on an intense concentration in concert with more sensitivity of
awareness, emotions, thoughts and sensory experiences 4. It is widely believed that an individual
who engages in meditative practices is likely to welcome both short and long-term benefits as a
result of alterations to the brain anatomically and functionally 4. With the growing popularity and
prominence of these longstanding practices, it is important to understand what the current
empirical data shows of meditation’s effects on the brain, in addition to a realization of its
practical uses. Western psychologists and neuroscientists alike have engaged in what is now a
fifty year old pursuit to understand these relationships and its implications on human
consciousness, neurobiology and everything in-between 4.
Types of Meditation Referenced in the Literature
As was touched on earlier, meditation refers to a broad collection of practices and types
both in the meditative theory and history, as well as in the empirical literature pertaining to the
practice. Where the literature varies from the theory however, is with the broad and often used
stratifications developed to qualify the practices into a more specific mode of cognitive
functioning. Much of the research elected to term the two classifications as being either “open
monitoring (OM)” or “focused attention (FA)” types of practice, and if these exact terms were
not used, ones that refer to the same concept were instead 2. The former is described as involving
attention on moment-to-moment unfolding of experience with a detachment from judgement or
reaction to the contents of cognitive patterns 2. The objective of OM meditation is to broaden the
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 5
attention to all the sensations and emotions being experienced. The technique is said to develop a
deeper level of awareness as well as a non-judgemental monitoring of brain activity 3. The latter
incorporates a primary focus of one’s attention on a particular object of interest (David and
Lutz). It is further characterized by a focus on a specific external or internal object of interest
while shutting out unrelated stimuli 3. FA meditation is believed to aid in attentional skills,
awareness of distracting stimuli, and redirection of one’s focus 3. Together, these two
classifications of meditation make up the majority of the techniques that were assessed in the
literature reviewed.
Neuroplasticity and Changes in Cognitive Functioning
The practices of meditation and mindfulness aim to produce a state of altered cognitive
functioning, thus an understanding of how the brain itself can be altered is of utmost importance.
The human brain has not only been determined to be plastic, but the potential extent to which its
plasticity can reach is constantly evolving 2. Research has long since proven that it is not only the
brains of children which could change, but the adult brain as well 2. Any anatomical or functional
variance from exercises or experience which is long lasting is considered to be as a result of
neuroplasticity 4. It is believed to be responsible for neural rewiring, afferent and efferent
trafficking reorganizations, expansion of neural conncetions, and sometimes other physiological
changes on a cellular or molecular level 3. With a more developed understanding of
neuroplasticity from an empirical perspective, it is now believed to be an imperative function of
the human brain and is considered to be pivotal for the ability to adapt to environmental and
physiologic demands, as well as overall experience 3.
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 6
It was once difficult to account for changes in cognitive functioning and development,
however with the incredible evolution of imaging technology researchers have been able to
acquire a lot of new and relevant data about the brain in action 4. One technology above the
others is most prevalent in the literature due to its versatility as well as its degree of clarity and
spatial resolution 4. Magnetic resonance imaging (MRI) is used to create a 3-D image of the brain
and is utilized often to explore a specific region or type of tissue 4. The new advancements in
imaging technology were pivotal in capturing empirical, significant data corroborating the belief
that the human brain does indeed change. A largely referenced example is a study that compared
young adults learning to juggle with those who did not. The MRI results generated great
evidence of learning-induced plasticity, as brain areas affiliated with handling and storage of
intricate visual stimuli exhibited structural changes in grey matter 6. A major design of the study
was to ensure the experimental group had no juggling experience in order to attempt to isolate
the changes as being specific to the training stimulus 6. This study was later redone on sixty-year
old volunteers, and produced the same results as the younger volunteers in a different study
referenced earlier 9 .Another frequently cited study that also elected to use MRI technology
generated images of both London taxi drivers and control groups in order to get a look at how
considerable navigation experience would affect the brain 7. The article not only cites much
larger hippocampi – a region of the brain known to produce spatial representations of an
environment – than the control group counterparts, but also went as far as to correlate size of the
hippocampal region with time spent being a driver 7. This statistically significant data validates
the brains potential to cultivate regional expansions to accommodate a higher dependence on a
skill in question, and also presents a relationship between the amount of time spent doing a skill
and the corresponding amount of regional change 7.
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 7
Meditation and Mindfulness’ Relationship to Neuroplasticity and Cognitive
Functioning
Neuroplastic changes have been evidenced to be a feature of any skill development, thus
meditation and mindfulness skills are no exception 8. Current evidence demonstrates how motor
imagery alone is able to enhance motor skill learning and performance 3. The hypothesized
explanation is that the cognitive functioning usually accessed during performance of the
movement is still being accessed during visualization of the movement, thus the neural pathways
are still being used and developed 10. This was further explored in 2005 by Pascual-Leone et al,
where they looked to demonstrate through their research that mental practice alone is enough to
encourage the progression of neural pathways 5. His findings cite positive alterations in brain
function and performance 5, which is not entirely surprising when one considers that these
techniques have been prevalent in the training of athletes for quite some time 10.
Despite the success of imagery, much of the attention amongst researchers has been on
the more traditional FA and OM meditation and mindfulness techniques, for its array of
purported benefits beyond attentional improvement. These practices have been linked to
improvements in monitoring conflicts, and other cognitive functions as a whole 3. Tasks subject
to improvement can range from verbal fluency, to cognitive inhibition and even working
memory 3. In multiple meta-analyses, meditation was cited to be supported by many areas of the
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 8
brain, however the most notable and frequent are frontal, parietal, temporal, and hippocampal,
and even brain stem regions 3. The practice was also cited to correlate with increases in volume
and concentration of cortical regions, grey matter, and white matter although the grey matter was
seen more often 3. Articles exhibit these steady modifications in grey and white matter in both
long and short term practice 3. When one continues to practice meditation, there are also
variations at the behaviour level, as there is an increase in many cognitive processes. Working
memory, executing different movements, attentional performance and other cognitive
enhancements present meditation as a tool to improve process specific learning, increasing its
potential for application in different circumstances 3.
Articles suggest both FA and OM meditation styles are aimed at developing cognitive
processes as opposed to being a cognitive skill on their own. It is for this exact reason that the
changes induced by meditation practices are believed to endure the passing of time, as they are
amendments to the processing itself and span many brain regions affecting many skills and traits
10. This is believed to be due to arousal of broad regions and pathways responsible for
psychological processing during meditation 10. Recent literature substantiates this idea, showing
that changes in brain and cognitive function as a result of meditation were present both during
the meditative practice as well as unrelated external activity 10.
These modifications are not limited to function however, as structural changes in areas
typically activated during meditation have been noted to be larger in long-term disciples
compared to those who are considered novice 10. In a separate but related study, advanced
meditators who have accumulated a minimum of one-thousand hours of experience showed
correlations with increased cortical thickness in the brain region responsible for adaptive control
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 9
of behaviour 10. The sum of the findings in the current body of evidence indicates that FA and
OM techniques cultivate cognitive skills that associate with marked differences in brain structure
and function 10. Furthermore, these modifications are linked with improvements in performances
of both internal and external tasks, as well as a reinforcement of the cognitive functions 10.
Key Studies Pertaining to Mindfulness and Meditation on Neuroplasticity and
Cognitive Functioning
There are plenty of published works existing that present the effects mental exercise like
meditation and mindfulness can produce. A topic of interest amongst researchers is the long-term
effects of meditation, which can be observed by examining differences between those who are
very experienced practitioners of meditation against controls who have little or no experience in
the practice at all. One study in particular compared 20 of these long-term practitioners to 15
control subjects using MRI imaging, and what was found was differences in cortical thickness 11.
Experienced meditators had increased thickness in regions involving the observation of both
internal and external stimuli 11. What’s more is that there are at least four additional studies that
corroborate these findings of increases in grey matter in the same regions of the brain 11. Two of
the studies displayed increases in at least two brain regions, while other studies showed more
regions affected 11. Another publication looked at the variations of brain structure in healthy but
stressed individuals, and gave insight into the alterations that come about in Mindfulness Based
Stress Reduction practices. In addition to all the expected changes in brain regions mentioned
earlier, the region associated with stress – the amygdala – was cited to decrease in size, denoting
not only anecdotal evidence of decreased stress, but also quantitative evidence 11.
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 10
Potential Uses and Efficacy as a Treatment Intervention for Mental Illness
Once it was established that meditation and mindfulness based practices brought on very
consistent and significant findings, it was not long before the implications would be examined in
a practical setting. Mental illness comes in many different forms, all of which are rooted in
variations of cognitive functioning. The empirical literature suggests there are many positive
influences on cognitive function associated with meditation practices, thus researchers were
eager to test its potential efficacy amongst a selection of mental illnesses. The current body of
evidence looks at how anxiety disorders, traumatic disorders, psychotic illnesses and other
diseases affecting cognitive function are all affected by mindfulness and meditation practices.
Anxiety is a mental illness that is well known and has deep rooted empirical data
showing efficacies of both pharmacological treatment and traditional methods 12. An article
looking at meditation on a neurobiological level linked reduction of cortisol and catecholamine’s
– markers of stress and anxiety – to meditation practices 12. A meta-analysis consisting of mostly
good quality randomized-control trials was strikingly implicative. The implications were that
meditative therapies are more than capable of managing anxiety symptoms, and in some cases,
proved to be more effective than other alternative therapies including pharmacological methods
12. Meditative therapies have shown potential in treating post-traumatic stress disorder (PTSD) as
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 11
well 13. An article published in 2012 in the journal ‘Behaviour Modification’ by Lang et al
reports “between a third and a half of patients receiving empirically supported treatments for
PTSD do not fully respond to treatment” 13. A well done systematic review compiled evidence
from three diverse forms of meditative treatments. The findings were that mindfulness
meditation has firm data supporting its efficacy as a PTSD treatment intervention, however there
are still things to be levelled out. For this reason, it is considered to be best used in combination
with another treatment. The other two have less data to draw conclusions from, however they do
show initial promise for PTSD treatment 13. Other streams of mental illness that are candidates
for this intervention are schizophrenia and psychosis. There were a couple of rare cases from
forty years ago that exhibited subjects who had a psychotic episode as a result of the
intervention, thus caution is required 14. Recent clinical findings indicate subjects have a better
ability to deal with negative thoughts and images present in the mind after meditation retreats
lasting only a few weeks, with treatment once a week 14. Long-term improvements in psychotic
symptom severity, psychological functioning and frequency of re-hospitalization were some
promising findings that were the result of a mindfulness-based intervention on people affected by
schizophrenia 14. There are other case studies that corroborate these findings, and strengthen the
efficacy, and thus potential for meditative techniques as a potential intervention in clinical
treatment.
Conclusion
The conclusion one arrives at after revising the current body of evidence is that there are
significant, positive results from meditative practices. These techniques consistently exhibit their
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 12
neuroplastic potential which has been seen to affect a wide variety of brain regions. Changes in
lobe sizes, concentrations of grey and white matter, and cortical thickness were all extraordinary
findings that were produced by these practices. The most exciting implications of the research
are undoubtedly the clinical applications among sufferers of a myriad of different mental
illnesses. Complications that are currently being treated by pharmacological means are not only
extremely costly in almost any health care system, but they also come with potential side-effects
or dangers that may have a patient trading one problem for another. This treatment intervention
is absolutely free as it requires nothing but variations in focus and cognitive functioning. In
addition, it can be done absolutely anywhere. These two reasons alone break down many barriers
that stand in the way between sufferers of mental illness and the treatment they need. There is
plenty of allure to a treatment intervention that combines therapeutic and spiritual approaches, as
benefits to health can extend past a specific illness and can reach as far as an increase in overall
well-being. Mindfulness therapy interventions aid with increasing levels of self-acceptance,
empowerment, and other positive emotions. The future steps to take with meditative practices
and research is to try and standardize the practice more, without removing the heart of the
practice itself. In addition, those conducting studies are advised to be more conscientious when
approaching these practices, as the delivery and teaching of these techniques are of vital
importance to its success. Striving to do these two things better will provide for even more
consistent findings and a better understanding in how to prescribe meditation as a treatment
intervention. As a whole however, meditation and mindfulness practices appear to be a potential
strategy for developing a healthy, well-functioning brain and may prove to be a cost effective
solution to a very serious mental health pandemic that the western world currently finds itself
facing.
M e d i t a ti o n , N e u r o p l a s ti c i t y , a n d M e n t a l I l l n e s s | 13
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