A brief introduction to Brain,Mind, Soul &Heart in SCIENCE & ISLAM : Written By ABU HAMID AL MALIBARI
(1) The human brain :
It is the center of the human nervous system. Enclosed in the cranium, the human brain has the same general structure as that of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Most of the expansion comes from the cerebral cortex, a convoluted layer of neural tissue which covers the surface of the forebrain. Especially expanded are the frontal lobes, which are associated with executive functions such as self-control, planning, reasoning, and abstract thought. Estimates vary for the number of neuronal and non-neuronal cells contained in the brain, ranging from 80 or 90 billion (~85 109) non-neuronal cells (glial cells) and an approximately equal number of (~86 109) neurons, of which about 10 billion (1010) are cortical pyramidal cells, to over 120 billion neuronal cells, with an approximately equal number of non-neuronal cells. These cells pass signals to each other via as many as 1000 trillion (1015, 1 quadrillion) synaptic connections. The brain monitors and regulates the body's actions and reactions. It continuously receives sensory information, and rapidly analyzes this data and then responds accordingly by controlling bodily actions and functions. The brainstem controls breathing, heart rate, and other autonomic processes that are independent of conscious brain functions.
The neocortex is the center of higher-order thinking, learning, and memory.
Researchers who study the functions of the cortex divide it into three functional categories of regions, or areas. One consists of the primary sensory areas, which receive signals from the sensory nerves and tracts by way of relay nuclei in the thalamus. Primary sensory areas include the visual area of the occipital lobe, the auditory area in parts of the temporal lobe and insular cortex, and the somatosensory area in the parietal lobe. A second category is the primary motor area, which sends axons down to motor neurons in the brainstem and spinal cord. This area occupies the rear portion of the frontal lobe, directly in front of the somatosensory area. The third category consists of the remaining parts of the cortex, which are called the association areas. These areas receive input from the sensory areas and lower parts of the brain and are involved in the complex process that we call perception, thought, and decision making. Different parts of the cerebral cortex are involved in different cognitive and behavioral functions.
Understanding the relationship between the brain and the mind is a great challenge. It is very difficult to imagine how mental entities such as thoughts and emotions could be implemented by physical entities such as neurons and synapses, or by any other type of mechanism. Incredulity about the possibility of a mechanistic explanation of thought drove René Descartes, and most of mankind along with him, to dualism: the belief that the mind exists independently of the brain. There has always, however been a strong argument in the opposite direction. There is overwhelming evidence that physical manipulations of the brain, for example by drugs, can affect the mind in potent and intimate ways. To put it crudely: if a man gets knocked on the head, his mind goes away. The large body of empirical evidence for a close relationship between brain activity and mind activity has led the great majority of neuroscientists to be materialists: people who believe that mental phenomena are ultimately reducible to physical phenomena.
Neuroscientists, along with researchers from allied disciplines, study how the human brain works. Such research has expanded considerably in recent decades. The "Decade of the Brain", an initiative of the United States Government in the 1990s, is considered to have marked much of this increase in research. A key source of information about the function of brain regions is the effects of damage to them. But analysis is limited by the fact that damage often crosses into multiple regions of the brain, not along clear-cut borders, making it difficult to draw firm conclusions.
(2) What is mind ?
[Soul sometimes functions as a synonym for spirit, mind or self.]
Which attributes make up the mind is much debated. Some psychologists argue that only the "higher" intellectual functions constitute mind, particularly reason and memory. In this view the emotions—love, hate, fear, joy,desire are more primitive or subjective in nature and should be seen as different from the mind as such. Others argue that various rational and emotional states cannot be so separated, that they are of the same nature and origin, and should therefore be considered all part of what we call the mind.
In popular usage mind is frequently synonymous with thought: the private conversation with ourselves that we carry on "inside our heads." Thus we "make up our minds," "change our minds" or are "of two minds" about something.
Understanding the relationship between the brain and the mind — mind-body problem is one of the central issues in the history of philosophy — is a challenging problem both philosophically and scientifically. There are three major philosophical schools of thought concerning the answer: dualism, materialism, and idealism. Dualism holds that the mind exists independently of the brain; materialism holds that mental phenomena are identical to neuronal phenomena;and idealism holds that only mental phenomena exist. The most straightforward scientific evidence that there is a strong relationship between the physical brain matter and the mind is the impact physical alterations to the brain have on the mind, such as with traumatic brain injury and psychoactive drug use.
Dualism and monism are the two major schools of thought that attempt to resolve the mind-body problem. Dualism is the position that mind and body are in some way separate from each other. It can be traced back to Plato Aristotle and the Samkhya and Yoga schools of Hindu philosophy, but it was most precisely formulated by René Descartes in the 17th century Substance dualists argue that the mind is an independently existing substance, whereas Property dualists maintain that the mind is a group of independent properties that emerge from and cannot be reduced to the brain, but that it is not a distinct substance.
Monism is the position that mind and body are not physiologically and ontologically distinct kinds of entities. This view was first advocated in Western Philosophy by Parmenides in the 5th Century BC and was later espoused by the 17th Century rationalist Baruch Spinoza. According to Spinoza's dual-aspect theory, mind and body are two aspects of an underlying reality which he variously described as "Nature" or "God".
Jose M.R. Delgado writes, "Aristotelian thought has permeated most Occidental philosophical system until modern times, and the classification of man's function as vegetative, sensitive, and rational is still useful. In present popular usage, soul and mind are not clearly differentiated and some people, more or less consciously, still feel that the soul, and perhaps the mind, may enter or leave the body as independent entities."
Various religious traditions have contributed unique perspectives on the nature of mind. In many traditions, especially mystical traditions, overcoming the ego is considered a worthy spiritual goal.
Judaism teaches that "moach shalit al halev", the mind rules the heart. Humans can approach the Divine intellectually, through learning and behaving according to the Divine Will as enclothed in the Torah, and use that deep logical understanding to elicit and guide emotional arousal during prayer. Christianity has tended to see the mind as distinct from the soul (Greek nous) and sometimes further distinguished from the spirit. Western esoteric traditions sometimes refer to a mental body that exists on a plane other than the physical.
Hinduism's various philosophical schools have debated whether the human soul (Sanskrit atman) is distinct from, or identical to, Brahman, the divine reality.
Buddhism posits that there is actually no distinct thing as a human being, who merely consists of five aggregates, or skandhas. According to Buddhist philosopher Dharmakirti, mind is defined as "that which is clarity and cognizes"—where 'clarity' refers to the formless nature of the mind and 'cognizes' to the function of mind, namely that every mind must cognize an object.The Indian philosopher-sage Sri Aurobindo attempted to unite the Eastern and Western psychological traditions with his integral psychology, as have many philosophers and New religious movements.
Taoism sees the human being as contiguous with natural forces, and the mind as not separate from the body.
Confucianism sees the mind, like the body, as inherently perfectible.
In Islam, 'mind' and 'soul' do not equate. Our souls combine the decision making ability of the mind along with the almost independent to body’s attribution of spirituality /corruption to it, For example here is the Quranic Verse “
“Allah takes the souls at the time of their death, and those that die not during their sleep; then He withholds those on whom He has passed the decree of death and sends the others back till an appointed term; most surely there are signs in this for a people who reflect.”
[39:42]
There is a hadith reported by Abd Allah ibn Mas'ud(RA), in which it is stated that the soul is put into the human embryo 40 days after fertilization takes place. This hadith is supported by some other hadiths narrated by Sahih al-Bukhari and Sahih Al Muslim.
The hadith is as follows: "Verily the creation of every one of you is brought together in the mother's womb as a drop of semen for forty days, then it becomes a clot for the same period, then it becomes a blob of flesh for the same period. Then the angel will be sent unto it to blow into it a SPIRIT, and the angel is ordered (to carry out) with four instructions, to write down its livelihood, the span of life, its deeds, and whether it is wretched or fortunate."
According to the Quran, Ruh (Soul) is a command from Allah (God).
"They put questions to you concerning the Spirit. Say the Spirit is at my Lord's command.and of knowledge only a meager part has been imparted to you." (Qur'an 17:85)
Imam-i Rabbani Shaykh Ahmad Sirhindi(rah)’s explanation:
“Brother! They {the sufis} have divided the contingent domain into three divisions: the
Spiritual World [<alam-I arwa:h], the Imaginal World [<alam-I mitha:l] and the
Corporeous World [<alam-I ajsa:d]. They have said that the Imaginal World is the
barzakh between the Spiritual World and the Imaginal World. They have also said that the Imaginal World is like the mirror of the meanings [ma<a:ni:] and realities [h*aqa:>iq] of both of these two worlds. It means that the meanings and the realities of the Spiritual World and the Corporeous World appears in the Imaginal World in the subtle form --- as there are many forms and figures [hi:>at] appropriate [munasib] for all the forms and realities. That Imaginal World, by its essential nature, never contain forms, figures [hi:>at] or shapes [ashka:l]. Forms or shapes [suwar wa ashka:l] are reflected therein from other Worlds, and find manifestation. It is analogous to the mirror --- the mirror, in its essential nature, never contains a form. The forms that are there come from the outside.
When you will be able to understand it, you will understand the following: Before its
attachment to the body [jasad], the spirit used to be in the Spiritual World. That is above
the Imaginal World. After its attachment to the body, when the spirit descends, it comes
down [furud= descent] to the Corporeous World due to its connection of love [be <alaqat
h*ubbi:]. It {the spirit} has nothing to do with the Imaginal World; neither before its
attachment to the body nor after its attachment to the body. Except that sometimes, when
the Exalted Lord has provided him with the opportunity, he sees [mut*a:l<ah] some his
own states in the mirror of that Imaginal World and learns what is good and what is bad
about those states. [husn wa qabih-i ahwal] So this is the interpretation for {unveiled}
events [wa:qi<a:t; Fazlur Rahman translates as mystic visions] and dreams [muna:ma:t].
Many a time, he {the sufi} can sense this meaning even without any sense perception
[h*iss]. After separation from the body, if the spirit is of high-mentality then it looks
towards the above. On the other hand, if it {the spirit} is of low-mentality then lower
realm captivates it. However, {in both cases} it has nothing to do with the Imaginal
World. The Imaginal World is for seeing not for being. The place for being is either the
Spiritual World or the Corporeous World. The Imaginal World is nothing except the mirror of these two worlds.
Question: As the Koran says, “Allah takes [yatawaffi:] the souls {of men} during their
death and for them who do not die during their sleep." {The Koran, Sura Zumar, 39:42}
From this, it’s understood that just like God may take someone’s soul during death, He
may also take someone’s soul during sleep. So how can you consider one as punishment
of this world and the other as the punishment of the last world?
Answer: God taking someone's soul [tuwaffi:] during sleep is of the type that someone
comes out [beru:n] of his familiar territory [watn ma:lawf-I khood] in the spirit of tasting
[dhawq] and longing [raghbat] for travelling [sayr] and sight-seeing [tama:sha:] until [ta:]
he attains fun and joy [farha wa surur]. Then he again [ba:z] returns home cheerfully and
joyfully [khurram wa sha:dema:n]. Where he travels [sayr gah-I uu] is the Imaginal World that contains many amazing [<aja:>ib] kingdoms and dominions [mulk wa malaku:t].
{In contrast,} God taking someone's soul during death is not at all the same. In that case,
his familiar realm [watn ma:lu:f-I khood] is destroyed [hadm] and the building where he
lives is devastated. [takhri:b-I bina:-I ma<mu:r] For this reason, there is no hardship and
suffering [mihnat and kolfat] in the "taking away of the soul" in sleep. Instead, it contains
fun and joy [farha wa suru:r].
{In contrast,} there is severity and suffering [shaddat wa kolfat] in the "taking of the
soul" in death. The familiar realm of the person whose soul is taken away during sleep
remains in this world and the treatment that he receives is the treatment of this world. In
the "taking of one's soul" [mutawaffi:] during death, after the destruction of his familiar
territory [watn-i ma:lawf], he moves away to the last world. So he is treated the same way
as he would be treated in the last world. You may have heard the hadith report, "Whoever dies, verily his Day of Destruction [qiya:mat] takes place."
(3) The Heart:
The human heart is a muscular organ that provides a continuous blood circulation through the cardiac cycle and is one of the most vital organs in the human body.The heart is divided into four main chambers: the two upper chambers are called the left and right atria and two lower chambers are called the right and left ventricles.There is a thick wall of muscle separating the right side and the left side of the heart called the septum. Normally with each beat the right ventricle pumps the same amount of blood into the lungs that the left ventricle pumps out into the body. Physicians commonly refer to the right atrium and right ventricle together as the right heart and to the left atrium and ventricle as the left heart. The electric energy that stimulates the heart occurs in the sinoatrial node(S.A.Node), which produces a definite potential and then discharges, sending an impulse across the atria. In the atria the electrical signal moves from cell to cell while in the ventricles the signal is carried by specialized tissue called the Purkinje fibers which then transmit the electric charge to the myocardium.
The sinoatrial node (also commonly spelled sinuatrial node, abbreviated SA node or SAN, also called the sinus node) is the impulse-generating (pacemaker) tissue located in the right atrium of the heart, and thus the generator of normal sinus rhythm. Although all of the heart's cells have the ability to generate the electrical impulses (or action potentials) that trigger cardiac contraction, the sinoatrial node normally initiates it, simply because it generates impulses slightly faster than the other areas with pacemaker potential. Cardiac myocytes, like all muscle cells, have refractory periods following contraction during which additional contractions cannot be triggered; their pacemaker potential is overridden by the sinoatrial or atrioventricular nodes.
In the absence of extrinsic neural and hormonal control, cells in the SA node, situated in the upper right corner of the heart, will naturally discharge (create action potentials) at about 60-100 beats/minute. Because the sinoatrial node is responsible for the rest of the heart's electrical activity, it is sometimes called the primary pacemaker.
If the SA node does not function, or the impulse generated in the SA node is blocked before it travels down the electrical conduction system, a group of cells further down the heart will become the heart's pacemaker. These cells form the atrioventricular node (AV node), which is an area between the atria and ventricles, within the atrial septum. If the AV node also fails, Purkinje fibers(or known by some as the bundle of his) are capable of acting as the pacemaker. The reason Purkinje cells do not normally control the heart rate is that they generate action potentials at a lower frequency than the AV or SA nodes.
ONCE AGAIN: What is the Sino Atrial Node?
- The sinoatrial (SA) node is a section of nodal tissue that is located in the upper wall of the right atrium. The SA node is also referred to as the pacemaker of the heart.
Function:
- Sets the rate of contraction for the heart.
- Spontaneously contracts and generates nerve impulses that travel throughout the heart wall causing both atria to contract.
The SA node of Heart is richly innervated by parasympathetic nervous system fibers (CN X: Vagus Nerve) and by sympathetic nervous system fibers (T1-4, Spinal Nerves). This unique anatomical arrangement makes the SA node susceptible to distinctly paired and opposed autonomic influence
The sinoatrial (SA) node is the pacemaker of the heart. More than any other tissue in the heart (apart from the atrioventricular node) the SA node is a complex tissue and its function depends on this complexity. This is the central thesis that this review will attempt to establish. From the study of the electrophysiology of single SA node cells, in particular, the pacemaking of the SA node is reasonably well understood. However, the relatively simple scenario that has emerged from these studies cannot account for the undoubted complexity of the SA node — for such well known phenomena as the marked heterogeneity of electrical activity throughout the SA node, the non-radial spread of the action potential from the leading pacemaker site in the SA node, the block of conduction from the leading pacemaker site towards the atrial septum, and pacemaker shift.s.
The heterogeneity of the SA node may be important in the effects of ageing on the SA node. With age in humans the function of the SA node deteriorates: the intrinsic heart rate (i.e. the heart rate in the absence of autonomic nerve activity) declines and SA node conduction time increases.
There are still many gaps in our knowledge of the SA node. Although much is known about central–peripheral differences in the SA node, it is clear that there are important superior–inferior differences and yet little is known about these.
HEART IN ISLAM:
Prophet Muhammad (saws) informed us in a very famous narration, commonly quoted with reference to lawful and unlawful, about the important role of the heart. He said: “Both lawful and unlawful matters are evident but in between them there are doubtful (suspicious) things and many people have no knowledge about them. So whoever saves himself from these suspicious matters (by staying away from them) saves his religion and his honor. And whoever indulges in these suspicious matters (will eventually) indulge in what is forbidden. This is like (the example of) a shepherd who grazes (his animals) near the Hima (private pasture) of someone else and at any moment he is liable to get in it. (O people!) Beware! Every king has a Hima and the Hima of Allaah on the earth is His illegal (forbidden) matters. Beware! There is a piece of flesh in the body, if it is reformed, the whole body becomes good, but if it gets spoilt the whole body gets spoilt; indeed it is the heart.” [Al-Bukhaari]
The Prophet(s) often used to supplicate, beginning with: "I seek refuge in You, O Allaah, from knowledge that does not benefit, and from a heart which does not fear." [At-Tirmithi, Abu Daawood, An-Nasaa’i and Ibn Maajah.
IS THIS ‘HEART’ IS OUR PHYSICAL HEART?
Imam Abu Hamid al Ghazali(rah) wrote in his ‘Kimia e Saada’. "The first step to self-knowledge is to know that thou art composed of an outward shape, called the body, and an inward entity called the heart, or soul. By "heart" I do not mean the piece of flesh situated in the left of our bodies, but that which uses all the other faculties as its instruments and servants. In truth it does not belong to the visible world, but to the invisible, and has come into this world as a traveller visits a foreign country for the sake of merchandise, and will presently return to its native land. It is the knowledge of this entity and its attributes which is the key to the knowledge of God.”
(4) Control of Heart & Brain and their INTER RELATIONSHIP:
Human Brain is a part of the nervous system ,which is an organ system containing a network of specialized cells called neurons that coordinate the actions of an animal and transmit signals between different parts of its body. In most animals the nervous system consists of two parts, central and peripheral.
The central nervous system of vertebrates (such as humans) contains the brain, spinal cord, and retina. The peripheral nervous system consists of sensory neurons, clusters of neurons called ganglia, and nerves connecting them to each other and to the central nervous system. These regions are all interconnected by means of complex neural pathways.
The autonomic nervous system (ANS or visceral nervous system) is the part of the peripheral nervous system that acts as a control system functioning largely below the level of consciousness, and controls visceral functions. The ANS affects heart rate, digestion, respiration rate, salivation, perspiration, diameter of the pupils, micturition (urination), and sexual arousal. Whereas most of its actions are involuntary, some, such as breathing, work in tandem with the conscious mind. It is classically divided into two subsystems: the parasympathetic nervous system (PSNS) and sympathetic nervous system (SNS).
The enteric nervous system is sometimes considered part of the autonomic nervous system, and sometimes considered an independent system.
WE KNOW THAT THERE IS AN INTEGRATED BRAIN ( SUPRA MEDULLARY) CONTROLOF HEART. The highest levels of organization in the Autonomic Nervous System are the supramedullary networks of neurons with way stations in the limbic cortex, amygdala, and hypothalamus. These supramedullary networks orchestrate cardiovascular correlates
of specific patterns of emotion and behavior by their projections to the Autonomic Nervous System .
Similarly fainting is a somatic and cardiovascular response to certain emotional
experiences. Stimulation of specific areas of the cerebral cortex
can lead to a sudden relaxation of skeletal muscles, depression of respiration,
and loss of consciousness. The cardiovascular events accompanying
these somatic changes include profound parasympathetic-induced
bradycardia and withdrawal of resting sympathetic vasoconstrictor tone.
There is a dramatic drop in heart rate, cardiac output, and SVR. The resultant
decrease in mean arterial pressure results in unconsciousness
because of lowered cerebral blood flow.
Vasovagal syncope appears in lower animals as the “playing dead” response typical of the opossum.
Brain death Vs Cardiac death:
Brain death is the irreversible end of all brain activity (including involuntary activity necessary to sustain life) due to total necrosis of the cerebral neurons following loss of brain oxygenation. Brain death may result in legal death, but still with the heart beating, and with Mechanical ventilation all other vital organs may be kept completely alive and functional, It is difficult for us to understand that a person who has a heartbeat can be brain dead, because historically the presence of a heartbeat indicated life.
So, my conclusion as an assumption is that Physical heart is having some unknown control over Brain. There are still many gaps in our knowledge.[Info about Medical sources-From Wikipedia]
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