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Brain is protected from thermal damage by a so-called radiator system: brain cooling system. As the brain gets hotter, the veins of this radiator system bring in cool blood from the evaporating surfaces of skin and craniofacial cavities. The craniofacial regions important in brain cooling system are very similar to the regions washed or wetted with ablution. So washing the face, oral and nasal cavities, and wetting scalp, ears and nape 4-5 times a day help the brain to remain cool throughout the day. This obviously means that with ablution cooler the head, healthier the brain. However, when a person is erect, the basal surface of the brain is in close contact with the cranial bones and therefore cerebrospinal fluid (CSF) could not cool the basal parts of the brain in erect position. Of course the relations of CSF to the skull and the brain are reversed when a person stoops (such as bowing and prostrating) allowing the CSF to intervene between the brain and the skull. Therefore stooping (as Muslims do about 120 times a day with prayer) would be beneficial for cooling the brain entirely by providing the CSF to wash-up the basal parts of brain. As for the other benefits of prayer, grounding is another aspect which provides a basis that restores and maintains natural electrical contact between the human body and the earth.
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J Exp Integr Med 2014; 4(2):147-149 ISSN: 1309-4572
http://www.jeim.org 147
HYPOTHESIS
Medical aspects of ablution and prayer
M. Kemal Irmak
High Council of Science, Gulhane Military Medical Academy; Ankara, Turkey
Received October 8, 2013
Accepted December 29, 2013
Published Online February 25, 2014
DOI 10.5455/jeim.291213.hp.010
Corresponding Author
M. Kemal Irmak
Gulhane Askeri Tip Akademisi
Yuksek Bilim Konseyi
06010 Etlik, Ankara, Turkey
mkirmak@gata.edu.tr
Key Words
Ablution; Brain cooling system;
Brain health; Prayer
Abstract
Brain is protected from thermal damage by a so-called radiator system: the brain cooling system.
As the brain gets hotter, the veins of this radiator system bring in cool blood from the evaporating
surfaces of skin and craniofacial cavities. The craniofacial regions important in brain cooling
system are very similar to the regions washed or wetted with ablution. So washing the face, oral
and nasal cavities, and wetting scalp, ears and nape 4-5 times a day help the brain to remain cool
throughout the day. This obviously means that with ablution cooler the head, healthier the brain.
However, when a person is erect, the basal surface of the brain is in close contact with the cranial
bones and therefore cerebrospinal fluid (CSF) could not cool the basal parts of the brain in erect
position. Of course the relations of CSF to the skull and the brain are reversed when a person
stoops (such as bowing and prostrating) allowing the CSF to intervene between the brain and the
skull. Therefore stooping (as Muslims do about 120 times a day with prayer) would be beneficial
for cooling the brain entirely by providing the CSF to wash-up the basal parts of brain. As for the
other benefits of prayer, grounding is another aspect which provides a basis that restores and
maintains natural electrical contact between the human body and the earth.
© 2014 GESDAV
BRAIN COOLING SYSTEM
Brain is protected from thermal damage by a so-called
radiator system: the brain cooling system. When human
is under heat stress, high brain temperature triggers
brain cooling system under the control of autonomic
nerves, which will reduce brain temperature [1]. That’s
important since a slightly overheated brain can bring on
convulsions, fainting, and brain damage. Two kinds of
veins and a number of craniofacial cavities are the
major components of this system. As the men get
hotter, the veins of this radiator system bring in blood
that is cooled as its heat radiates away through
evaporation of water (sweat or mucus) from the
surfaces of skin and craniofacial cavities [1]. Activation
of brain cooling system thus protects the brain from
thermal damage.
Components of brain cooling system in human
Emissary and angular veins, nasal cavity, paranasal
sinuses and tympanic cavity are the major components
of brain cooling system in humans.
1) Emissary veins: Emissary veins connect the
intracranial veins with veins outside the cranium
related to nasal cavities (nostrils), scalp (top of the
head), posterior auricular region (outside of the ears)
and nape (back of the neck) [2]. These emissary veins
serve as pathways through which cool blood from the
evaporating surfaces of the head could flow into the
cranium and cool the brain under the control of
autonomic nerves [3].
2) Angular vein: The angular vein which drains blood
from the eye, the nose, and the lips forms a route to the
brain for the cool venous blood returning from the
evaporating surfaces of the nasal mucosa, lips and eye
corners [1, 2]. Fig.1 shows the craniofacial regions
contributing to cooling the brain with emissary and
angular veins.
3) Nasal cavity and paranasal sinuses: Evaporative
heat dissipation from the upper respiratory tract is
known to be a significant source of heat loss during
hyperthermia [4, 5]. The evaporation of water at the
mucosal surfaces of the nasal turbinates makes the
venous blood cooler for brain [6-9]. The paranasal
(frontal, ethmoid, maxillary and sphenoid) sinuses
which are mucosa-lined airspaces within the bones of
the face and skull also form an important component of
the brain cooling system [10]. The cooling occurs
through convection process caused by evaporation of
mucus and the transfer of the cool venous blood from
paranasal mucous membranes to the brain [11]. The
rostral base of the brain is also cooled by conduction to
the nearby paranasal sinuses [12, 13].
4) Tympanic cavity: The tympanic cavity
communicates with the nasopharynx via the auditory
tube which allows air to enter and leave the tympanic
cavity, whereas it is in close contact with the middle
cranial fossa and the internal carotid artery [2]. These
anatomical arrangements provide an important basis for
cooling the adjacent brain lobes and cranial vessels by
either conduction or convection.
The blood destined for the brain is cooled by these
evaporating surfaces of the head [14, 15]. Such
vascular arrangements allow a bulky transfer of venous
blood from the skin of the head and from nasal and
Irmak: Aspects of ablution and prayer
148 DOI 10.5455/jeim.291213.hp.010
paranasal mucous membranes to brain and provide an
excellent anatomical basis for the brain cooling system
caused by evaporation of sweat or mucus [11]. This
cooling system protects the brain from overheating and
its efficiency is increased by evaporation of water on
the head and by ventilation through the nose [16].
Temperature changes are then transmitted to the
cerebrospinal fluid (CSF) compartment which in turn
influences the brain temperature directly or indirectly
[11]. The cooler CSF washes the walls of the brain and
the brain temperature decreases. Thus the concept of
brain cooling system implies that the CSF takes up heat
from the warmer brain and transfers it to the cooler
blood in the veins. So the anatomical arrangements in
human provide favorable conditions for the transfer of
heat from the whole brain to the skin of the head,
tympanic cavity and upper respiratory tract [1].
Figure 1. Craniofacial regions important in selective brain cooling.
The blood destined for the brain is cooled by these evaporating
surfaces of the head. Notice that the same areas are washed or wetted
in ablution.
POSITIVE EFFECTS OF ABLUTION AND
PRAYER ON BRAIN HEALTH
Daily prayer is the cornerstone of religious practice in
Islam. The one who wants to establish these prayers
must be physically clean with ablution. Ablution is
required before all prayers and needs to be refreshed
after sleep and any waste is excreted from the body
[17]. Ablution is quite a simple procedure and its
craniofacial aspects are performed as detailed below:
-Rinse the mouth out three times,
-Rinse the nostrils with water three times,
-Wash the face from the forehead to the chin, and from
the ear to ear three times
-Using wet hands, rub them over the top of the head
starting at the forehead, wiping backwards
-Using wet fingers, wipe the inside and outside of the
ears, and the nape (back of the neck).
One can easily notice the similarity between the
craniofacial regions important in brain cooling system
and the regions washed or wetted with ablution (Fig.1).
So washing the face, oral and nasal cavities, and
wetting scalp, ears and nape 4-5 times a day help the
brain to remain cool throughout the day. This obviously
means that with ablution cooler the head, healthier the
brain. Therefore wetting the evaporating surfaces of the
head drained by emissary and angular veins (scalp,
face, nape, ears, mouth and upper respiratory tract)
several times a day would be beneficial for cooling the
brain entirely. The report that wet hair in cold weather
may cause sinus headache and posterior eye pain
supports our view about the beneficial effects of
ablution for brain cooling system [16]. Nasal, instead of
mouth breathing must also be encouraged for keeping
the brain cool [1, 17].
Each prayer is a series of postures in which portions
from the Qur’an are recited and the believer makes
supplications. Muslims pray five times a day: early
morning, noon, afternoon, evening and at nightfall. To
pray five times a day takes about 40 minutes to perform
[18]. As part of the prayer, a person goes through a set
of movements such as standing upright, bowing down
(40 times a day), prostrating (putting forehead on the
ground, 80 times a day) and sitting. Bowing as a
praying position was also explained in Bible; Exodus
34:8, Nehemiah 8:6, Psalm 72:11.
As the brain is slightly heavier than cerebrospinal fluid
(CSF), the basal surface of the brain is in close contact
with the cranial bones in the floor of the cranial cavity
when a person is erect. In this position CSF is not
present between the inferior parts of brain and the
cranial bones. Hence CSF normally cools the superior
part of the brain and brain cooling system could not be
implemented for the basal parts of the brain in erect
position [1, 2]. Of course the relations of CSF to the
Journal of Experimental and Integrative Medicine 2014; 4(2):147-149
http://www.jeim.org 149
skull and the brain are reversed when a person stoops
(such as bowing and prostrating) allowing the CSF to
intervene between the brain and the skull [19]. So the
physical movements during prayer provide the CSF to
wash-up the basal parts of brain. Therefore stooping (as
Muslims do about 120 times a day with prayer) would
be beneficial for cooling the brain entirely.
Other positive effects of prayer on human health
As for the other benefits of prayer, earthing or
grounding is another aspect which must be considered.
The surface of the earth possesses a limitless and
continuously renewed supply of free or mobile
electrons as a consequence of a global atmospheric
electron circuit [20] and it is suggested that barefoot or
hand contact with the earth (earthing) promotes health
by stimulating the migration of charges into the body
[21]. The beneficial effects of earthing may be a result
of direct earth connection with palmar and plantar
Merkel nerve endings which enables both diurnal
electrical rhythms and free electrons to flow from the
earth to the body [22-24]. Wearing shoes with
insulating soles has disconnected most people from the
earths electrical rhythms and free electrons [20]. In
situations where going barefoot on the earth is
impractical, putting hands (palms) on earth as Muslims
do about 80 times a day with prayer (with a continuous
plantar contact on earth for 60 minutes) provides a
basis that restores and maintains natural electrical
contact between the human body and the earth [23].
In conclusion, as the cornerstone of religious practice
in Islam, daily prayer with ablution has positive effects
for both brain and body health through brain cooling
system and grounding.
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