On A Possible Psychophysiology of the Yogic
S.M. Roney - Dougal, PhD,
Psi Research Centre,
Somerset BA6 8HN, Britain.
Recent theoretical research by myself into the pineal gland
as the physical locus of ajna chakra, conceived in yogic tradition
as being the psychic centre of our being, is extended here to
explore the yogic idea of ajna chakra as the command chakra,
in command over all the other chakra centres. I have come across
multiple references to the importance of melatonin as the off-switch
for the endocrine glands’ output of hormones, working together
with the pituitary gland which is considered to be the on-switch.
I am suggesting that the pineal gland is the physical aspect
of ajna chakra; the thyroid of vishuddhi; the breasts of anahata;
the adrenals of manipura; and the gonads of swadhistana and
muladhara. These endocrine glands are all positioned at the
traditional points of the chakras and their functions are remarkably
equivalent to the traditional descriptions of the chakra functions.
I am therefore proposing that the endocrine system is the physiological
aspect of the yogic spiritual tradition of the chakras, and
that the autonomic nervous system can be equated with the yogic
Over the last quarter of a century, there has been increasing
interest in "translating" the knowledge of one system
into the language of another. For example, 20th century physicists,
have been comparing quantum mechanics with mystical knowledge
as exemplified by Fritjof Capra in "The Tao of Physics"
(1975). This same process has been occurring in psychology,
for example Tart's "Transpersonal Psychologies" (1975),
Paranjpe's "Theoretical Psychology" (1984), both examining
Eastern philosophies and religions from a Western psychological
standpoint, and research exploring a neurological basis for
Near-Death Experiences and their similarity with the kundalini
experience (Wile, 1994; Jourdan, 1994).
Much of this translation has, of necessity, been in very general
terms, since we have to clarify the overall picture first. I
seem to be involved in this process from a rather different
perspective. I have been researching a specific topic, the pineal
as a psi-conducive gland, which has generalized to the endocrine
system as the physical aspect of the yogic chakra system. I
must stress that what follows is still in a speculative and
The Yogic Chakra System
The yogic chakra system as explained by Swami Satyananda Saraswati
(1972), consists of seven chakras which are normally depicted
as a sort of "spinal column" with three channels called
nadis (ida, pingala and sushumna) which interweave, the crossing-points
being the sites of the chakras (See figure 1). In western terms
this can be readily understood as the central nervous system
(sushumna) in the spinal cord around which, on either side,
runs the autonomic nervous system which has two aspects, the
parasympathetic which can be readily correlated with ida, and
the sympathetic with pingala, the sympathetic and pingala being
the activating aspect of the system and the parasympathetic
and ida the relaxing. Where these two cross they form plexuses,
or nodes, from which nerves go out to, for example, the heart,
lungs, diaphragm, digestive system and the endocrine organs.
Satyananda connects this nervous system with the chakras.
These chakras are considered to be important points for the
channelling of consciousness, energy nodes linking the physical
with the spiritual. They have been adopted quite widely into
popular usage in the West, partly through the Theosophists at
the turn of the century, and partly because of the intense interest
in Eastern spirituality birthed during the sixties. There are
at present so many differing correspondences and attributes
linked to them and therefore this research is presented with
the aim of achieving greater clarity.
Table 1: Different Correspondences Popularly Linked with the
2)For Comparison I Show An Alternative Set of Correspondences
As Outlined by John Davidson (1989)
The Pineal Gland: Ajna Chakra
As a parapsychologist I am interested in the Indian lore surrounding
ajna chakra which is held to be the psychic centre. This corresponds
very closely with our Western lore which considers the pineal
gland to be the "third eye" or the “seat of the soul.”
For example, Swami Satyananda (1972) states that: "The
name Ajna comes from the root "to know" and "to
obey and to follow". Literally the word Ajna means "command"
. . . . Yogis, who are scientists of the subtle mind, have spoken
of telepathy as a "siddhi", a psychic power for thought
communication and clair-audience etc. The medium of such siddhis
is Ajna chakra, and its physical terminus is the pineal gland."
I have found that his concept of the pineal gland as the psychic
chakra and as the command chakra has a sound psychoneuroendocrinological
The pineal gland is situated in the centre of the brain and
its main function is to make neurohormones which affect both
the brain and the body. The pineal works together with the pituitary
through the hypothalamus controlling the endocrine system. Basically
it is one of the regulators of our circadian rhythm, is implicated
in our emotional state, reproductive function, possibly dream
sleep and in certain psychoses. Melatonin is the best studied
of the pineal neurohormones and was first isolated from cattle
in 1963. Before this the pineal was generally considered in
the West to be vestigial. Amphibians and reptiles have light
sensitive cells in the pineal gland which for them is literally
a light sensitive third eye at the top of their brain just below
their skull. In humans fibres from the inferior accessory optic
tract go to the pineal; these are separate from the main optic
tract bundle, which suggests that the light sensitivity of the
pineal is not necessarily related to sight (Eichler, 1985).
Most people have heard of the pituitary gland, which is often
known as the "master gland" in that the hormones it
makes exert a controlling effect on the endocrine organs. Well,
we can think of the pituitary as being an "on switch"
and the pineal as being an "off switch" (the mistress
gland) in that it works with the pituitary by switching off
the endocrine organs. The form of ajna chakra is traditionally
depicted as bilobed and we can understand this to be the joining
of the two glands, pituitary and pineal, which makes very good
sense from a neuro-endocrinological point of view. To me this
makes much better sense than assigning the pituitary to sahasrara,
the crown chakra, as some systems do, since sahasrara is better
understood as the culmination of everything, the whole rather
than any of the parts. Just as muladhara is considered by Satyananda
to be the top chakra of animals and the bottom of humans, so
sahasrara can be understood as the top chakra of humanity and
the bottom chakra of the next order of being, whatever that
The Psychic Chakra: Pinoline
There is a large body of neurochemical and anthropological
evidence which suggests that the pineal gland may produce a
neuro-modulator that enhances a psi-conducive state of consciousness.
An abstract of this research was presented at the Parapsychological
Association Convention in 1985 (Roney - Dougal, 1986). For full
details of this research please see Roney-Dougal (1988, 1989,
1990, 1991, 1993). In brief, the pineal gland has been found
to synthesise various beta-carbolines and peptides, and to contain
enzymes that produce psychoactive compounds such as 5-methoxy
dimethyltryptamine (5MeODMT) “The two precursors that are most
likely to be involved in the synthesis of such compounds are
serotonin (5-hydroxytryptamine, 5HT) and tryptamine” (Strassman,
1990). These have wide-ranging effects throughout our brain
and body, affecting the gonads, adrenals, pancreas, thyroid,
and other emotional and endocrine activities.
Of most interest here are the neuromodulators called beta-carbolines
which are MAO inhibitors that prevent, amongst other effects,
the breakdown of serotonin. This results in an accumulation
of physiologically active amines within the neuronal synapses
which may lead to hallucinations, depression or mania depending
on the amines being affected (Strassman, 1990). Beta-carbolines
are also found in the retina of the eyes, in the adrenal glands
and in the gut. The pineal contains the greatest concentration
of serotonin in the brain, this being accentuated in those who
suffer from psychoses. The pineal also contains enzymes that
inhibit synthesis of these compounds, thus suggesting a regulating
mechanism within this gland. There is a suggestion that it is
the action of the pineal beta-carbolines, in particular 6-Methoxytetrahydro-betacarboline
(6MeOTHBC, now being called pinoline), on serotonin that triggers
dreaming (Callaway, 1988). Spontaneous case collection studies
(e.g. Rhine, 1969) have found that most (more than 60%) spontaneous
psi experiences occur during the sleeping and dreaming state
of consciousness, which suggests that the dream state is a state
of consciousness wherebey we are most likely to have psi expereinces,
and pinoline is suggested to be the neurochemical that triggers
this particular state of consiousness.
Further, there is now a considerable body of research into
the action of serotonin and melatonin in relation to psychiatric
disorders such as manic-depression (Halaris, 1987) and schizophrenia
(Miles & Philbrick, 1988). "At a psychopharmacological
level, carbolines are central nervous system inhibitors via
the gamma-aminobutyric acid (GABA, a neurotransmitter) system.
This action is similar to that of benzodiazepines, (e.g. diazepam
or "Valium"), which relieve anxiety, have anticonvulsant
action, are hypnotic and muscle relaxants and are used for all
these CNS pharmacological actions. Thus pinoline may also act
as a physiological tranquilliser and hypnotic, and the latter
effect would be in keeping with the nocturnal secretion pattern
of pineal activity."
Anthropological data also suggest that these beta-carbolines
are psi-conducive because their chemical structure is very similar
to a naturally occurring group of chemicals called harmala alkaloids
which occur in an Amazonian vine, Banisteriopsis caapi, used
by Amazonian tribes for psychic purposes (Roney - Dougal, 1986
& 1989). The Amazon has a huge variety of psychotropic plants,
yet all the tribes throughout that vast area use this same vine
mixed with Psychotria viridis (Nai kawa) which contains dimethyltryptamine
(DMT) (Ott, 1993 & 1994), for healing, out-of-body experiences,
clairvoyance and precognition. It is traditionally used only
when psi experiences are desired, though nowadays it is also
used for general initiatory purposes. Thus the tribal people
make a mixture of harmala alkaloids and DMT which mimics the
tryptamine-pinoline mixture ascribed to the night time output
of the pineal gland. My speculation is that when the pineal
gland is stimulated to produce pinoline we are more likely to
enter an altered state of consciousness which is psi-conducive.
In the 1960's a Chilean psychotherapist, Claudio Naranjo (1973,
1978) used a variety of hallucinogens including harmaline (one
of the harmala alkaloids) in the psychotherapeutic setting,
and came to the conclusion that: "Harmaline may be said
to be more hallucinogenic than mescaline . . . both in terms
of the number of images reported and their realistic quality.
In fact some subjects felt that certain scenes which they saw
had really happened and that they had been as disembodied witnesses
of them in a different time and place. This matches the experience
of South American shamans." (Naranjo, 1967). Ott (1993)
considers that the harmala alkaloids are not actually hallucinogenic
in their own right but that they permit the DMT in the ayahuasca
mixture to be absorbed into the blood stream so that these create
the entheogenic effects. This is still a matter of debate. There
is extensive evidence from many anthropologists which suggests
that the Banisteriopsis vine together with Psychotria Viridis
is a psi-conducive drug, particularly with regard to remote
viewing, clairvoyance and precognition but so far there has
been no experimental test of these claims (Kensinger, 1973).
Ayahuasca has recently been investigated by Don et al (1996)
who suggest that its action is consistent with their other research
into brain function and psi experience.
Thus, the anthropological evidence suggests that harmala alkaloids
mixed with DMT stimulate a psi-conducive state of consciousness;
the neurochemical evidence suggests that the harmala alkaloids
are an analogue of pinoline which is produced in the pineal
gland, noting that in the comparison between the action of the
harmala alkaloids and pinoline it must be remembered that a
one-position change in methoxy grouping can be profound in its
action. The Yogic and occult teachings and common folk lore
all say that the pineal gland is the psychic centre and I suggest
that the pinoline made by the pineal gland at night time, through
its action on serotonin, stimulates a dream type state of consciousness
which is psi-conducive.
The Command Chakra: Melatonin
However, the yogic lore not only equates ajna chakra with
the psychic centre of our being, but also as the command chakra.
For an understanding of the pineal gland as command chakra we
have to look to its main action which is the production of the
neurohormone melatonin. Melatonin is found in protozoans, suggesting
that it dates back a thousand million years, and is found in
all animals. It is important in bird migration cycles, dogs'
moult cycles, and frog colour change. In this article I refer
both to research with humans and with animals in order to obtain
as full a picture as possible of the relationship between the
pineal gland and the endocrine organs since there has been relatively
little research with humans, whilst being very aware that one
should not extrapolate too much from animal data as is the tendency
so often these days in biological and psychological research.
Therefore, as far as possible whenever the data come from animal
studies I state this explicitly.
The most important function of the pineal gland is maintaining
the biological clock, both on a daily basis according to the
sun, on an annual basis according to length of day, and on a
lunar basis as well. The study of the biological rhythm is called
chronobiology and it has been found that there is a genetic
connection, a basic inner clock, and an environmental connection
through the retina: light stimulates the monosynaptic retinohypothalamic
pathway which leads directly to the anterior hypothalamic suprachiasmic
nucleus (SCN), pineal and hypothalamus.
Within the pineal the circadian rhythm regulation is achieved
through the actions of serotonin and melatonin. Serotonin is
made during the day and melatonin at night. Acute exposure to
light at night suppresses melatonin production. The intensity
of light required to suppress production varies between species
and in humans is 2000 lux. It has been suggested that perhaps
rhodopsin is the photopigment that mediates the suppressive
effect of light on pineal. Blue light seems to be maximally
inhibitory (500 - 520 nm). Acute exposure to nonvisible, non-ionising
radiation, e.g. extra low frequency (ELF) 60 Hz electric and
magnetic fields also suppresses melatonin production as does
pulsed static magnetic field exposure. There is speculation
that these effects are also mediated via the eyes (Wetterberg,
1995, Reiter & Richardson, 1992).
Serotonin is a very important neurotransmitter in the brain
and its action has been linked with mental states such as psychosis,
with entheogenic plants, with our mood circuits and therefore
with illnesses such as appetite disorders (anorexia and bulimia).
It is a very complex neurotransmitter with 5 or 6 different
receptor sites, which means it has many different modes of action.
Melatonin is made from serotonin through the action of two
enzymes, serotonin n-acetyl transferase (NAT) and hydroxy-indole-O-methyltransferase
(HIOMT). Melatonin production is determined primarily by neural
activity from the hypothalamic suprachiasmic nucleus (SCN) and
there is a feedback relationship with the endocrine glands.
Gonadal steroids, pituitary gonadotrophins, thyroxine, prolactin
and the adrenal hormones intervene in the mechanisms governing
All humans have a circadian rhythm though the magnitude of
NAT production varies greatly. In general there is good correlation
between pineal NAT activity and pineal and plasma melatonin
rhythms. The rhythm at birth is linked to that of the mother;
maturation of the cycle accompanies growth of sympathetic nerve
fibres into the gland; melatonin production peaks just prior
to puberty at which time there is a sudden and dramatic drop,
and from then on it gradually decreases into old age. In people
who suffer from depression the circadian rhythm is disrupted.
The most important neuronal function of melatonin is as a sleep
inducer. It has been found to ease insomnia because it causes
drowsiness, and also to combat jet lag because it helps to reset
the biological clock: 5mgs per day helps induce sleep and helps
airline workers adjust to new time zones. (Cowley, 1995) Is
there a genetic component in early or late risers? Hypophysectomy
(loss of the pituitary gland), which causes depressed metabolic
activity, and bilateral adrenalectomy blunt the nocturnal melatonin
rise though the rhythm stays the same.
Being forced to exercise (swim) at night causes a rapid drop
in pineal melatonin levels in rats, but not in NAT or HIOMT
activity. Melatonin production stays as normal, and blood levels
rise dramatically suggesting it is being rapidly released from
the gland into the blood system. Removal of adrenals doesn't
change this so normal stress hormones are not implicated. This
finding has profound implications for the health of night workers
(Reiter & Richardson, 1992) because melatonin also modulates
release of stress hormones, thereby controlling heart attacks
and stomach ulcers.
Jogging or other exercise is a mood enhancer since it stimulates
endorphins. Exogenous opiates increase melatonin levels, and
beta-endorphin levels decrease when melatonin is administered.
Opiates stimulate basal prolactin secretion. Opioid receptor
antagonists also decrease prolactin concentrations although
continuous administration does not affect circadian rhythm of
prolactin, which is related to melatonin levels.
Recent research suggests that melatonin is involved in the
aging process and that giving 19 month old mice melatonin each
evening in their water improved their weight, their vigour,
their activity levels and their posture when compared with the
untreated mice and they lived almost 200 days longer on average
(20%) (Maestroni et al, 1989). Touitou et al (1989) measured
melatonin levels in people in February, March and June and found
that old people have half the amount of melatonin that young
men do (we make half as much by age 45 as we do when children),
that senile people show far less circadian rhythm, with elderly
women showing least variation. For all groups, all through the
year melatonin production peaks between 2 - 3am with the largest
amplitude in January. Inter-individual variations are large
in all groups. Since pinealocytes and enzyme activity are not
altered in the pineal of the elderly, the decline of plasma
melatonin levels may well be related to a modification in the
release of the hormone and/or to an increase in its metabolism
or excretion. An increased sensitivity to light could also explain
the relatively low levels of plasma melatonin in the elderly.
Melatonin production decreases as we age, the thymus gland
shrinks and we produce fewer antibodies and T-cells. There are
special melatonin receptors on cells and glands of the immune
system. A recent controversial speculation is that nightly melatonin
supplement boosts the immune system thereby preventing cancer
and extending life. Research has suggested that melatonin protects
cells from oxidation by free-radicals, which contribute to at
least 60 degenerative diseases, including cancer, heart disease,
cataract and Alzheimers. In this respect melatonin differs from
other natural antioxidants, B-Carotene, vitamin E and vitamin
D in that melatonin is absorbed into target cells and exerts
its action from that intracellular position with much greater
effect (Reiter, 95). Melatonin reduction is linked to the calcification
process that starts at puberty. People taking chlorpromazine,
an anti-psychotic medication that raises melatonin and prolactin
levels have low rates of breast cancer. Prolonged exposure to
high oestrogen levels raises breast cancer levels and melatonin
inhibits oestrogen release.
It thereby also helps to prevent pregnancy because of its interaction
with the reproductive system as a hormone inhibitor. This inhibitory
action means that melatonin controls puberty; without it we
would be sexually active at 4 - 5 years old. Parapineal tumours,
those that lie next to the pineal, stop the pineal from functioning
and lead to percocious puberty and progeria (accelerate aging);
while pinealomas, tumours of the pineal gland itself, produce
excess melatonin secretion and delayed puberty.
Thus melatonin functions to affect the body in ways which are
traditionally connected with yogis: yogis are said to live for
many years longer than normal; are considered to be relaxed
and stress-free people; to be able to control many of their
physical functions, such as heart rate, circadian rhythm and
metabolic rate; celibacy is linked to the religious life, and
within yoga there is also the tantric path; and they are considered
to enjoy excellent health.
Through the light sensitivity of the pineal gland and its primary
role within the biological clock system, regulating the rise
and fall of the metabolic system and switching off the endocrine
glands, which I am going to expand on next, we can see that
the concept of the pineal as the command chakra is as strong
as the concept of the pineal as the psychic chakra.
The Thyroid Gland: Vishuddhi Chakra
According to Satyananda (1972), vishuddhi chakra is located
in the throat and is the centre of "the nectar of immortality."
It is connected with the sense of hearing and thus with the
ears, and of course with the vocal cords and with self-expression.
The thyroid makes thyroxine which regulates the metabolic rate
of the body, i.e., it controls how fast the body runs: an overactive
thyroid means that the heart beats fast, one becomes thin, sexual
desire increases, and the mind works overtime; whilst an underactive
thyroid has the opposite effect. Neurochemically, the thyroid
is under the inhibitory control of the pineal gland, removal
of the pineal resulting in thyroid enlargement and increased
hormonal secretion rate. The pineal is also under feedback control
by the glands which it influences. Pineal cells respond to thyroxine,
the response being particularly strong at night.
Synthetic melatonin has the effect of inhibiting iodine uptake
and the secretion of thyroxine, and, given at the correct times,
can reproduce the daily and annual biological rhythms since
iodine uptake naturally decreases during the night. Thus, evening
injections of melatonin are more effective than morning ones,
showing that the time of day when hormone supplementation is
given is a significant factor, the influence of the circadian
rhythm once again. (Johnson, 1982). The effect of synthetic
melatonin on the secretion of thyroxine decreases after puberty.
The hypothalamus makes thyroid releasing hormone (TRH), which
stimulates the pituitary to make thyrotropin (TSH), which stimulates
the thyroid to make thyroxine . There is a circadian variation
in human TSH levels, TSH beginning to rise several hours before
the onset of sleep, reaching maximum levels between 11.00pm
and 4.00am, declining gradually with a minimum at 11.00am. People
with hypothyroidism also show a seasonal variation and circadian
changes in plasma TSH, which suggests that the circadian rhythm
of TSH is not related to the negative feedback control exerted
by thyroid hormones under normal conditions: serum thyroxine
levels show maximum concentration in late morning and minimum
concentration in early morning.
Sleep deprivation results in larger and broader TSH peaks. Pinealectomy
does not result in changes in serum TSH or hypothalamic TRH
content, nor does it produce alterations on the diurnal rhythms
of hypothalamic TRH - so there is little firm evidence for significant
interactions between melatonin and rhythmicity of TSH secretion,
yet chronic melatonin treatment decreases pituitary TSH content
and increases plasma TSH concentration.
TSH is, together with melatonin and the adrenals, involved in
coping with long term stress. Alpha-adrenergic pathways play
a role in the stimulatory control of TSH release. Circadian
changes in cortisol levels follow an opposite pattern to those
of TSH. Glucocorticoid administration has an inhibitory effect
on TSH secretion and rhythmicity, but there does not seem to
be a close relationship between the daily profiles of each hormone
and abolition of the circulation rhythm of cortisol does not
disrupt the TSH rhythm. Glucocorticoids inhibit TSH release,
and so the circadian rhythm of TSH is abolished in patients
with hypercortisolism (Johnson, 1982).
Stress is intimately connected with metabolic rate, heart rate,
an overactive mind, and also with age as an older person cannot
cope with stress as well as a younger person. Long term stress
is very different from short term stress (which is dealt with
by the adrenals) and it is interesting that ajna, vishuddhi
and manipura are all concerned with stress - which also affects
the heart - when the mind just won't stop going in circles around
the problem (the beta-rhythm mental chatter), which is one of
the worst aspects of long term stress. These are all the negative
aspects of vishuddhi and we learn through meditation to overcome
these aspects and so to become peaceful, still, calm and to
live to a ripe old age which is another way of saying that the
thyroid is connected with immortality. Relaxation is the first
step in meditation; slowing down, letting go, releasing the
stress, stilling the endless internal chatter as is exemplified
so well by the Chinese symbol of immortality, the tortoise;
the slower you go, the longer you live. Yogic lore states that
it is perfectly possible to regulate the functioning of the
endocrine system, thus learning how to control one's metabolic
rate. It is feasible that yogic exercises designed for the ajna
chakra do physically regulate the pineal gland and so influence
the functioning of the other endocrine organs.
The Heart Centre: Anahata chakra
According to Satyananda, anahata chakra is concerned with will
and with feeling, touch, the skin especially the hands, manifesting
in such arts as painting, poetry and music, which are aspects
As a result of the writings by Theosophists, many people consider
that anahata chakra is connected with the thymus gland, which
physiologically is most active in children and is concerned
with the immune system. Recent research suggests that there
is a connection between the pineal gland and the thymus because
of its interaction with the immune system, as mentioned in the
section on the pineal gland as command chakra. Functional connections
between the immune and the neuroendocrine systems are being
increasingly recognized. Thus stressful effects, distress, from
psychological or neuro-endocrinological causes may adversely
affect the immune system and vice versa.
Circadian synthesis and release of melatonin exerts an important
immunomodulatory role, in that it appears to be a physiological
up-regulator of the immune system and to operate via the endogenous
opioid system on antigen activated cells. When given in the
evening to mice it increases the primary antibody response to
T-dependent antigens, buffers the depression of antibody production
and thymus weight induced by the acute restraint of mice innoculated
with sheep red blood cells, and confers resistance against injections
of a virus, not by protecting the thymus cortex but because
it enlarges the thymus medulla. The anti-stress action of melatonin
appears to be antagonized by administration of the opioid antagonist
naltrexone, suggesting that melatonin operates via the endogenous
opioid system (EOS) even though the opioid system is not itself
involved in the immunological effect of acute stress. When administered
in the morning no effect on the immune system was found (Maestroni
et al, 1989). Thus, it is possible to see melatonin as an anti-stress
hormone since melatonin reverses the depression of antibody
production induced by corticosterone in drinking water. Failure
to cope with distress may be dependent on an exhausted EOS and
melatonin may restore the EOS.
So there is some connection between the pineal and the thymus
in animals, and yet whilst there is a certain link between keeping
healthy and the normal concept of the emotional aspect of heart
in our culture, there is another hormone connected with this
region in humans which expresses heart emotion much more strongly:
the hormone prolactin which is connected with lactation in the
I have noticed in my research into the pineal that melatonin
is the off-switch for a hormone called prolactin which is made
by the pituitary, is involved with pregnancy and stimulates
lactation, and is implicated in manic-depression. Most of the
research with prolactin has been with animals, but there has
been some research with humans showing once again the link with
the pineal gland.
In seasonally breeding species in which both hormones show
a seasonal variation, melatonin mediates the influence of light
on prolactin release. All ruminants (e.g. cows, sheep) show
a marked seasonal fluctuation in plasma prolactin concentration,
i.e. high in summer and low in winter, and certain animals become
impregnated in autumn at the end of the long day light hours
(Wurtman, 1979), this fluctuation being controlled by melatonin.
This inhibition of prolactin secretion in ruminants inhibits
implantation of the blastocyst during the winter, so that the
foetus does not implant into the womb until spring time, even
though mating and fertilisation occurred in autumn.
Prolactin secretion in women is also controlled by the ovarian
steroids, its level being modified by the fluctuating oestradiol
levels of the menstrual cycle. Whilst few clinicians would accept
a seasonal basis for reproduction in humans, older epidemiological
data, and data more recently derived from conditions of borderline
fertility, both support a seasonal change. The exact link to
melatonin is as yet unestablished but seasonal changes in plasma
melatonin have been described (Matthews, 1981) for women, but
not for men. Martikuinen et al (1985) found peaks in both summer
and winter, and Touitou et al (1984) found differences between
young and old people (see Vishuddhi chakra).
Webley (1988) worked with 11 young men intermittently over
a 9 month period. He found that, like melatonin, prolactin shows
a night time peak around 3 - 4.00 am. and that, whilst inter-individual
variations are large, there are no changes in the amplitude
of the peaks across the February, March and June samplings.
This significant positive correlation between melatonin and
prolactin concentrations is greatest at night and strongest
in June. Melatonin concentrations decrease earlier than prolactin
in the morning and increase before prolactin in the evening
(see Table 3).
Prolactin concentration increases with sleep. The dependence
on sleep is independent of time of day, so night workers will
make some of their prolactin during the day, but prolactin also
shows a circadian pattern of high levels at night. There were
inconsistent changes in the circadian pattern of melatonin for
the individuals, which suggests that environmental factors other
than the light/dark cycle can influence the circadian pattern
in men, and as I am suggesting here, stress/relaxation is one
of these factors - other factors may be sleep/activity pattern,
different social cues and physical exertion.
Webley found that melatonin doses given both morning and evening
stimulated a significant increase in prolactin concentrations.
There is a diurnal rhythm in sensitivity to melatonin: melatonin
given in the morning stimulates a constant increase in prolactin
concentration across the sampling period, whereas in the evening
a peak in prolactin was evident after 90 -120 mins.
This leads to the conclusion that it is possible that melatonin
may control directly the nocturnal increase in prolactin, but
in some cases if melatonin concentration is increased, prolactin
concentration is decreased; for example, a decrease in melatonin
by pinealectomy results in an increase in prolactin release
and the nocturnal increase in prolactin is absent in a pinealectomised
human who had no nocturnal increase in melatonin. The observed
stimulation of prolactin after melatonin injection in the human
is also at odds with the inhibition of prolactin release in
seasonally breeding animals - this may be indicative of a difference
between the response to acute and chronic melatonin administration
as is also seen with thyroxine, or may be indicative of the
different responses to the hormones between humans and animals.
In rats acute administration of melatonin stimulates prolactin,
whereas prolactin is inhibited with chronic melatonin. Melatonin
can inhibit dopamine release from the rat hypothalamus, the
degree of response showing circadian variation. Since dopamine
is known to inhibit prolactin release, the influence of melatonin
on prolactin may therefore be via a dopaminergic mechanism.
Such a mechanism would provide a central site of action for
melatonin on human reproduction (Webley,1988).
Like TRH, prolactin secretion during the day follows the opposite
pattern to that of cortisol. Glucocorticoid administration reduces
pituitary prolactin content and release as well as prolactin
responses to TRH, but does not affect circadian rhythm.
Oestrogens stimulate prolactin secretion, so women have higher
basal levels, particularly during reproductive years and pregnancy.
There is a close parallel between plasma oestradiol and prolactin.
Women have higher sleep-related prolactin elevations. Further,
hypersecretion of prolactin and the related pituitary hormones,
luteinising hormone (LH) and human growth hormone (HGH) may
be associated with affective (mood) disorders such as manic
depression and recurrent depression - here we see clearly the
link between emotional, physical and psychological state of
being through its disturbance. Further, dopamine antagonism
is a feature of major tranquillisers which may cause high prolactin
levels; dopamine neurotransmitter dysfunction is associated
with schizophrenic disorder and Salvador (1988) considers that
dopamine is the most important inhibitory regulator of prolactin
and TSH synthesis.
I am suggesting that the hormones are the physical aspect of
the chakras. Every hormone appears to have a physical component
which affects the workings of the body. They also appear to
have an emotional component, and I am suggesting that prolactin
is the hormone of the emotion we associate with love, which
most cultures associate with the heart. Prolactin is made in
men as well as women and children, for all of our lives, and
has functions other than the primary one of lactation. It is
intimately connected with melatonin and hence ajna chakra, with
TRH and hence with vishuddhi chakra, with glucocorticoids and
our stress levels and with oestrogen and hence female sexuality.
As the hormone of love this makes perfect sense.
The Solar Plexus: Manipura Chakra
Satyananda says that manipura chakra is located behind the
navel and causes old age, decay and emaciation by burning up
the nectar of immortality. It is also connected with the sense
of sight and the eyes and it is the organ of action and hence
is also connected with walking, the legs and the feet. The solar
plexus is the locus for our "gut feelings" about people
and situations, and is connected with digestion and assimilation.
It has also been linked with ambition, will, self-assertion,
vital energy, power struggles, anger and jealousy. Manipura
is the uppermost of the "earthly" or base chakras.
There are two possible endocrine organs in the gut which could
be linked with manipura: the pancreas and the adrenals.
The adrenals are the endocrine glands I consider are most
strongly related to manipura. Most people know these as the
"fight or flight" glands in that adrenaline is produced
when we are in a stressful situation and we burn up our body
energy in order to cope with a crisis; adrenaline is the hormone
of action. We feel the fire in our belly.
The pineal is connected with the adrenals, and in particular
with adrenaline and the corticosteroids in many ways. The adrenals
comprise two parts: the cortex and the medulla. The cortex secretes
glucocorticoids such as corticosterone, on a rhythmic light-dark
cycle linked with hormones from the pituitary and the hypothalamus.
The glucocorticoids are involved with sugar metabolism and as
The cortex also secretes mineralocorticoids which are involved
in mineral balance, and also anxiety;
The third sort of hormones produced by the cortex are the androgenic
steroids which include testosterone, are involved in body building
and anger; there is a steroid surge in the morning to help wake
These are the stress-related hormones.
The adrenal medulla secretes adrenaline. The pineal inhibits
release of all of these hormones, thus controlling our physical
level of immediate short-term stress - as it does with the thyroids
on a long-term basis. Melatonin is actually found in the gut
as are the beta-carbolines. Beta-carbolines interact with adrenaline
and noradrenaline uptake and outputs as well as with corticosterone
secretion, thus interacting closely with the adrenal functions.
Constant administration of small doses of beta-carbolines causes
the weight of the adrenals to increase, whilst removal of the
pineal gland causes enlarged adrenals. The significance of this
enlargement of adrenals, as with the thyroids, when for some
reason or other there is no pineal, is that the inhibitory effect
on these glands has been removed so that they work overtime.
And, as a result, one burns up. This can be understood in the
spiritual as well as in the physical sense.
Some systems consider that the pancreas, which is involved
in digestion and the input of energy and energy maintenance
(the Islets of Langerhans within the pancreas make insulin,
a glucose using hormone, and glucagon, a glucose saving hormone),
is the endocrine organ of manipura chakra. This would make very
good sense in terms of our Western concept of the solar plexus,
and is certainly to be considered. Davidson (1989) mentions
insulin and glucagon in this connection as the food factory
of the body, that which gives us our physical energy.
However, there is a connection with the adrenals because the
pancreas is turned off by adrenaline and noradrenaline, and
adrenaline regulates the uptake of glucose. Therefore the pineal
is connected with the pancreas via the adrenals.
The Root of the Spinal Cord: Swadhistana Chakra
Swami Satyananda states that swadhistana is connected with
all "the phases of the unconscious", the subliminal
mind. "Swadhistana is made up of all the rubbish which
you never wanted, which you never needed, which you never desired
but which got in." (Satyananda, 1972). Traditionally it
has also been linked with sexuality, sensory pleasure, liquid,
taste, procreation, self-indulgence, the kidneys and the prostate
I think that swadhistana is connected with the generative aspect
of sexuality embodied by the womb in women, with follicle stimulating
hormone and luteinising hormone, oestrogen and androsterones
as the hormones of this chakra. These hormones are central to
the development of the secondary sexual characteristics - that
which makes a man a man and a woman a woman - they define our
gender, our selves as sexual people, the pitch of our voice,
the shape and strength of our body, whether or not we have a
beard, and the differing emotional characteristics related to
oestrogen and testosterone - that which is the essence of man
There is a strong link between the pineal gland and the generative
aspect of sexuality. Melatonin levels in the mother are exceptionally
high during pregnancy reaching a peak at birth. The diurnal
rise in plasma melatonin appears enhanced as pregnancy progresses,
supporting the idea of a role for the maternal pineal in entraining
foetal body rhythms.
In animals, there is a biological clock oscillating in the
SCN during foetal life before circadian rhythms are overtly
expressed and before the retino-hypothalamic pathway has innervated
the SCN. (i.e. A unique form of maternal communication coordinates
the phase of a developing circadian clock until the developing
mammal can respond to light directly through its own eyes.)
The foetal SCN shows circadian variation in metabolic activity
that is in time with the rhythm in the mother and with the external
lighting cycle. Research by Reppert et al (1988) has found that
this foetal circadian rhythm can be detected in rats as early
as the 19th day of gestation. Pineal NAT is the first measurable
circadian rhythm evident, accurately reflecting circadian output
from the SCN. Pups reared in an environment with no light cues
express a NAT rhythm that is in phase with the circadian time
of the mother.
In humans circadian rhythms are not obvious until well into
the postnatal period. Human SCN neurons are formed by the 28th
week. A significant fraction of incident light is transmitted
into the uterus of a pregnant woman. It is possible that direct
photic entrainment augments or even replaces maternal-foetal
coordination of circadian phase since the foetus can synthesise
and store melatonin. Also after birth social cues are very important
in entrainment of sleep-wake cycle. (Reppert, 1988)
Vasopressin messenger ribonucleic acid (mRNA) can also be used
as an intrinsic marker of the oscillatory activity of the SCN
during foetal life since a circadian rhythm of vasopressin levels
in cerebrospinal fluid originates in the SCN. Vasopressin mRNA
levels exhibit a prominent day-night variation in adult rats,
which begins in the foetal SCN on day 21 of gestation in phase
with the mother's rhythm. In mothers whose SCN has been destroyed
on day 7 of gestation, the entraining signal for the foetus
no longer works, and the foetal SCN metabolic activity has no
day-night rhythm. Also the pineal NAT activity for 10 day old
pups born to SCN-lesioned mothers and reared in constant darkness
is completely disrupted and they have no daily rhythm. But,
if the mother's SCN is lesioned after foetal neurogenesis of
SCN then foetal synchronization is not disrupted. Destruction
of the maternal SCN also eliminates a circadian rhythm to birthing.
Possibly also the developing circadian clock is involved in
initiating parturition, as different species have different
times of day when birth is more likely to happen.
When pups are fostered with a mother whose circadian rhythm
is opposite to that of their natural mother, their rhythms change
to become synchronous to that of the foster mother. In these
cases entrainment of rhythm is possibly linked with feeding
activity which occurs on a rhythmic basis. One needs to have
the pup entrained so that its feeding cycle is in tune with
the mother and the other pups. This ensures that its activity
cycle is such that it emerges from the burrow at a safe time
of day. When litters with many pups are born they need to all
be synchronised in their activity.
Thus the strong connection between the pineal gland and the
gonadal system is very apparent in connection with pregnancy
and birth. The glandular connection of swadhistana is with the
gonads and related systems so that to some extent it overlaps
with muladhara chakra, and so I look to other aspects of our
sexuality - puberty and the menstrual cycle - in the discussion
The Coccygeal Plexus: Muladhara Chakra
According to Satyananda, muladhara chakra is the root chakra,
intimately connected in the male with the testes, and in the
female with the cervix, and with the perineum and anus for both
sexes. This chakra is connected with the sense of smell, the
nose and the earth element, with passion, the animal instincts,
anger, greed, excretory functions, secretory and sexual aspects,
attachment, material security, survival and materialism. Working
on this chakra releases suppressed emotions and unconscious
memories, and causes extreme swings in mood. It is the seat
of kundalini, and has obvious and direct connections with sexual
energy in its most earthy aspect.
Some systems link the root chakra with the adrenal glands even
though the adrenals are located above the kidneys back of the
navel. The only information I have come across which justifies
this idea is that in embryology the gonads and suprarenals all
start in the same place, and the adrenal cortex makes small
amounts of androsterones. However, I consider that the yogic
description of muladhara chakra and particularly its connection
with kundalini suggests sexuality as its primary physical manifestation
and therefore I link this chakra with the gonads, with testosterone
in men which is primarily made by the testes (Wilson & Foster,
1992), and with oestrogen and progesterone in women.
As we have already seen the pineal and the gonadal system interact
extensively. Satyananda considers that there is a special connection
between ajna chakra and muladhara, and there are certainly extensive
connections between the pineal gland and the gonads. The pineal
synthesises antigonadotropic peptides. In their turn the gonadal
hormones, inhibit the biosynthesis of the pineal hormone melatonin,
although gonadectomy has little influence on magnitude of melatonin
increase or on phasing of the rhythm, and prolactin secretion
is inhibited by ovarian steroids, suggesting that there is a
physical as well as spiritual, mental and emotional links between
mind, heart and sex.
Melatonin inhibits gonadal development in children and regulates
the onset of sexuality at puberty for humans. There is a fall
in plasma melatonin associated with male human pubertal development.
The pineal normally becomes calcified at puberty (Ng & Wong,
1986; Vaughan & Reiter, 1986), and there is a sharp decrease
in melatonin production at this time.
The pineal nighttime melatonin concentration decreases progressively
during the menstural cycle, with an increase at ovulation and
peak values during menstruation. Melatonin seems to be "taken
up" by the ovaries, testes and uterus. Thus women show
a 28 day melatonin rhythm, though many women have a menstrual
cycle that is more closely correlated with the 29.5 day lunar
cycle and menstruate every full moon. Those using the contraceptive
pill have less melatonin since there is a positive relationship
between melatonin and progesterone. Melatonin secretion is significantly
higher during the late luteal phase than during the preovulatory
phase and melatonin levels fall before ovulation: this could
be the determinant of the menstrual cycle. The onset of the
LH surge is in the early morning when melatonin levels are falling
(Brzezinski & Wurtman, 1988). Continuous light, which causes
a decrease in melatonin production, also causes a decrease in
ovarian melatonin concentration, whilst injections of melatonin
result in smaller testes.
I consider that these studies linking the pineal gland with
the gonadal endocrines aids understanding of the lore surrounding
sexuality and psychic functioning. Children and celibates were
almost universally those chosen as temple seers and prophets,
the oracle at Delphi being an excellent example of this. Some
research suggests that children are more psychic when they are
younger, and much of the research into poltergeists suggests
that adolescents are often the focus for this wild uncontrolled
Our knowledge of the endocrine system, the chemistry of our
body-mind and emotional system, is still meagre. The neurochemists
have only just isolated pinoline from the pineal and are still
learning about melatonin and serotonin. However, partial as
our knowledge may be, it does fit together with what the yogis,
"scientists of the subtle mind," tell us about the
yogic chakra system. Our disciplines, apparently so different
in language and method, appear to corroborate each other.
In conclusion, pinoline can be seen as the physical aspect
of ajna chakra as the psychic chakra, and melatonin as the neurohormone
of ajna chakra as the command chakra in that it has an inhibitory
role for the endocrine organs, many of which are found physically
at the traditional places where the chakras are located. Thus
vishuddi at the throat links with the thyroid which is the metabolic
regulator, anahata at the heart with the breasts, manipura at
the navel with the adrenal glands involved with our reactions
to stress, and swadhistana and muladhara at the root of the
spinal cord with different aspects of the genital system. There
are a bewildering number of versions of the yogic chakra system:
attempts to correlate the chakras with Western physiological
models may not only help us understand physiology, but also
help us find the version of the chakra system that makes the
most sense physiologically. Perhaps by linking this spiritual
system with Western psychoneuroendocrinology we can create a
deeper understanding of the links between mind, body and spirit
for the benefit of all of us.
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Thanks are due to all those people who have helped me collect
and amass this body of knowledge, most particularly to Anne
Silk for searching Medline for me; to Ian Pearson for a fascinating
afternoon's conversation, for correcting my errors in the first
draft of this paper, for assistance in the details of the second
draft, and for the gift of a valuable book; to Elizabeth Whitehouse
for her eternal supply of interesting information and ideas;
to Ellis Snitcher for sharing his expertise in neuroendocrinology
Table 3: Circadian Rhythms of Melatonin, TSH and Prolactin