The Artistic Mind

By Goutam Ghosh

The human mind is a mysterious article of an individual; how it develops and works that trail a longstanding debate. Some people do not even accept the existence of the mind. But it does exist, without which a human being loses identity. This book apprises the origin and development of the mind and its different states, such as Creative and Wise minds. How do nature and nurture help develop a human mind? Can science artificially improve a natural human brain or develop a super-intelligent artificial brain? Does the universe, or our nature, have a mind? The mind mingles consciousness. Is our universe conscious? It’s a great question, which fuels the name of this book, The Artistic Mind.

• Language: English
• Publisher: One Point Six Technologies Pvt Ltd
• Release date: Oct 18, 2022
• ISBN: 9789356670105

Goutam Ghosh

GOUTAM GHOSH, Ph.D., is a materials scientist. Besides his hobbies, he is passionate about the natural forces and their interactions associated with various incidences in the universe, human physiology, and the mind.

Book preview

chapter 1

BRAIN

As long as our brain is a mystery, the universe, the reflection of the structure of the brain will also be a mystery.

— Ramòn y Cajal

The brain is an intricate and power-consuming organ in the human body. In the rest condition, an adult brain uses about 20% of the body's total haul. The brain's primary function, i.e., processing and transmitting information, is expensive concerning energy utilisation. Two-thirds of the brain's energy goes into information processing, and the remaining third to maintaining the health of the nerve cells (neurons), the building blocks of the brain. Glucose, produced from food intake, is the source of energy that comes as adenosine triphosphate (ATP) through blood circulation. This chapter elucidates the structures and functions of the human brain. The brain-mind relationship is inseparable; thus, a brief knowledge of the brain anatomy helps to appreciate various aspects of the mind. The mind can elevate to a higher level as a Creative Mind or a Wise Mind through nurturing the brain.

Historically, human evolution started on earth nearly eight million years ago, from Chimpanzees to the present Homo sapiens; thus, the brain structure also changed. As early humans faced new environmental challenges and evolved into bigger bodies, the brain also enlarged and became more complex. Over the course of human evolution, brain size tripled, and the modern one is the largest and most complex of any living primate, has an average weight of around 1,352 g (2.98 lb) with different anatomic regions for special functions.

According to the evolutionary chronology, the human brain has two distinct regions - the old region and the new region. The old region is similar to most other animal species, often termed the reptilian brain. It's located deep within the central region of the brain, in an area called the limbic region. It is the seat of raw, instinct-based emotion. The new region is uniquely human. This spongy folded brain region lies beneath the forehead near the prefrontal cortex (PFC). It is disproportionately large compared to all other animal brains (25-50% greater in total volume). It is the seat of cold, calculated reason, where planning, reasoning, and execution happen. The former evolved half a billion years ago, and the latter a mere hundred thousand years ago. A few connecting neuronal pathways run between the old limbic system and the new neocortex for necessary but seldom communication among them.

One of the primary reasons why the human brain has evolved to look so far into the future is so that we can take actions in the present that will bring us to a better future rather than a worse one.

— Daniel Goldstein

Does the human brain evolve further after the birth of a child? Yes, the size and neural connections increase, but the basic anatomy remains unchanged. It is a dynamic system, and some minor changes occur even in an adult brain, which makes a person mentally different from others and think differently. A person could be innocent, clever, or romantic. Exceptionally intellectual and creative people are considered geniuses who contribute significantly to society, and future generations remember them. I briefly discuss three geniuses: John von Neumann, Srinivasa Ramanujan, and Johann Sebastian Bach.

John von Neumann (December 28, 1903 - February 8, 1957), a Hungarian-born American mathematician-cum-physicist, computer scientist, engineer, and polymath, was a rare genius. At his six, he could multiply eight-digit numbers mentally while conversing in Greek with his father and instantly solve mathematical problems of any difficulty level. He had a photographic memory. One of his remarkable contributions was a logical design for computers that paid attention to such concerns as data storage and processing of instructions. This design, known as von Neumann architecture, became the basic concept of most computers. His work on ‘artificial life' was also exceptional, which focussed on the problem of the self-reproduction of machines. In the book ‘Theory of Self-Reproducing Automata,' he introduced cellular automata, a theoretical model of a device that could reproduce if it had the exact description of how to build itself. Cellular automata can also describe a wide range of phenomena like the interaction of genes or the development of multicellular organisms.

Srinivasa Ramanujan (December 22, 1887 - April 26, 1920) was born in Tamil Nadu, India. He was a self-taught maths genius who contributed significantly to various areas, including the analytical theory of numbers, elliptic functions, continued fractions, and infinite series; he drafted self-discovered identities, equations, and theorems in his notebooks. He received an invitation to join the group of G.H. Hardy for a Ph.D. work without a formal university degree. Seeing Ramanujan's notebooks, Hardy said, I had never seen anything in the least like them before. A single look at them is enough to show that could only be written by a mathematician of the highest class. They must be true because, if they were not true, no one would have the imagination to invent them. Later, Bruce Berndt, a renowned mathematician, spent decades researching Ramanujan's theorems and wrote books on them.

Johann Sebastian Bach (March 21, 1685 - July 28, 1750) was a German musician. Was he a genius? If it means rational and productive, then Bach was a genius. He composed music for all seasons, which no other composer could do with similar excellence. His music cunningly expresses his craft encyclopaedically. He was a master of every musical form of his day, including pianos and many other organs. Bach also created musical interpretations of the Bible using choruses, arias, and recitatives. These works are his Passions, the most famous of which is Passion According to St. Matthew.

Has a genius a different brain from others? There are a few intriguing differences between the brain of a genius and a normal noggin. These differences may come out through the exploration of the brain anatomy that reaches its completion in the prenatal stage, though the size and neural connections continue growing with a peak in middle age. There is much to be said for a genius's approach to thought in general. A genius often tries many different avenues to arrive at the desired result, rather than deciding which one will work and which ones not.

How much does brain performance depend on genetic and epigenetic factors? The genetic factors are inherited, while the epigenetic factors arise through interactions with fostering environments. The environmental factors include the nurture and nutrition that children receive in their childhoods. Certain nutrients are essential for brain development, such as protein, energy, specific fats, iron, zinc, copper, iodine, selenium, vitamin A, choline, and folate. Neuron being the building block of the brain, I shall present its structure and function first, and the brain anatomy.

Neuron: structure and function

The neuron is the primary building block of the brain. There are about 100 billion (i.e., 100,000,000,000) neurons connected in a complex network. The connectivity between neurons is vital for information processing in the brain and other parts of the body till the substructure of the skin. The mind, the human identity, originates due to the uninterrupted flow of electrochemical signals through these neuronal networks.

Figure 1.1. Structure of a neuron.

The brain receives external stimuli from sensory organs (eyes, ears, noses, tongue, and skin) via the neural circuitry, process them, and returns the responses. Different types of neurons do facilitate these activities. For example, sensory neurons carry signals such as pain from a sense organ to the brain, motor neurons from the brain to the muscles to control the movements of body parts, and interneurons between different neurons in the body. These electrochemical signals to and from neurons deal with the flow of ions.

Figure 1.1 shows the structure of a neuron. The shape and size of the neuron vary depending on its function and location. Neurons have three main components - dendrites, cell bodies, and axons. Dendrites and axon terminals are the entry and exit paths of the signals to and from the neuron cells.

The cell body is called soma, which has a nucleus, Golgi body, endoplasmic reticulum, mitochondria, and other components. The nucleus contains chromosomes that carry genes. The spatial and temporal regulation of gene expression¹ in neurons is a vital step in creating functional and structural networks. Recent research has revealed that neurons can control the expression of proteins in a new synthesis and re-establish the neuronal connections against any damage.

Neurons can divide to produce new neurons even in adult human brains but only in two regions: (1) the granule cell layer of the olfactory bulb and (2) the dentate gyrus of the hippocampus. The sub-ventricular zone that produces neurons during brain development retains some neural stem cells in the adult, which can divide into both new stem cells and differentiated cells; the differentiated cells turn into active neurons and glial cells.² However, the generation of new neurons is limited only to recovery from injuries in the central nervous system, such as the spinal cord.

While carrying information, soma receives inputs through dendrites and makes repeated decisions - whether or not to fire and release ions down its axon - up to a thousand times per second. After a firing, the cell needs a short recovery time of a few milliseconds before the subsequent firing. The dendrites receive signals from neighbouring neurons through synapses and pass them on to soma as input signals.

Axon is a tube-like structure that carries electrochemical impulses from soma to its terminals (nerve endings), which eventually will cross over into the entry ports of one or more neighbouring neurons, causing them to make the same sort of decision. Axon has an intermittent coating called the myelin sheath, which comprises plasma membranes of glial cells to form a lipid structure and increase the speed of information propagation. The gap between the terminals of two neighbouring neurons is called a synaptic cleft. The axon terminals contain small vesicles packed with neurotransmitter molecules such as dopamine.

The decision of firing the signal from one neuron to the other is made simply as: if the sum of all impulses exceeds a certain threshold, the transmission is activated; otherwise, not. There may be as many as 10,000 separate entry ports to a neuron, which means up to 10,000 separate summands may be involved in determining the neuron's subsequent action.

In case of a yes decision, a pulse of ions streaks down the axon towards the nerve ending. Then there is a series of intricate steps for the signal to cross over the synaptic cleft, e.g., depolarisation³ of the terminal membranes, activation of voltage-gated Ca²+ channels,⁴ entry of the Ca²+ ions, changing the conformations of docking proteins,⁵ a fusion of vesicles to the plasma membranes in the entry paths of the target neurons, and release of neurotransmitters into the synaptic cleft, which then bind to the receptors of the targeted cells.

The brain controls physiological activities, such as keeping the body in homeostatic condition, creating feelings of pain and fear, and helping reasoning and decision making. These are possible through instant communications between the brain and the rest of the body through neuronal pathways. These communications are active twenty-four hours a day. The flow of the electrochemical signals in the brain produces different brainwaves that generate the mind.

Inside the cranium,⁶ there are twelve nerves called cranial nerves (CNs); olfactory and optic nerves are two for sensing smell and eyesight, respectively. CNs join respective body organisms directly with the brain.

Brain anatomy and function

The brain anatomy is a specialised subject, but a brief elucidation of the brain's structure and function may help understand human intelligence and consciousness.

Figure 1.2. The human brain's structure: (a) different lobes and components, (b) grey and white matter, and (c) neural networks of the brain.

The human brain has two identical hemispheres of folded mass, each having three distinct anatomic areas — cerebrum, cerebellum, and hypothalamus, as shown in Figure 1.2(a); the cerebrum is a substantial part. The outer few millimetres of each cerebral hemisphere contain a layer called the cerebral cortex. The size of the cerebral cortex is the main difference between the human brains and the brains of less intelligent species. The cerebrum has four major regions: frontal lobe, parietal lobe, occipital lobe, and temporal or limbic lobe; each consists of neurons, neural stem cells, glial cells, and blood vessels. Glial cells, or glia, play a supporting role for neurons.

The link between the two hemispheres is a broad, thick, and flat bundle of commissural fibers beneath the cerebral cortex, consisting of 300 million (i.e., 300,000,000) nerve fibers and around 10 cm long; it is called corpus callosum or callosal commissure, shown in Figure 1.2 (b), which maintains a steady flow of information related to sensory, motor, and cognitive nerves between the two hemispheres. Each hemisphere controls the opposite side of the body, i.e., substantial damage to the motor neurons in the right hemisphere causes the left portion of the body to paralyse. The structures and functions of different brain regions are briefly narrated below.

Frontal lobe

Figure 1.2(a) depicts the sizeable frontal lobe in the front part of the cerebrum having four primary gyri; each gyrus (singular form of gyri) is a ridge on the folded cortex, surrounded by many sulci (plural form of sulcus). Gyri and sulci create a larger cortical surface in the brain for better cognitive function in a smaller cranium. The human brain undergoes gyrification in the fetal and neonatal stages. Abnormalities in this folding structure cause neurological disorders such as epilepsy and mental disparage such as intellectual or learning disability and psychogenic retardation. The frontal cortex contains both pre and primary regions of the motor cortex. Damage in the frontal lobe can occur under several conditions, e.g., stroke and head trauma, which may cause diseases like dementia.

The frontal lobe is responsible for creating long-term memory, attention, motivation, and future planning like self-management and decision making, and the frontal cortex undertakes the planning, controlling, and executing of voluntary movements. Broca's area⁷ in the frontal lobe (not shown in the figure) helps to convert thoughts into words. Damage to this area can undermine the ability to speak, understand language, or produce recognisable speech. The frontal lobe is also responsible for empathy.

Parietal lobe

It is the middle part of the cerebrum and has four subdivisions: the somatosensory cortex, inferior parietal lobe, superior parietal lobe, and precuneus.

The somatosensory cortex receives and processes sensory information, such as touch, temperature, and pain, coming from sense organs. The signal reaches this area via neuronal pathways through the spinal cord, brain stem, and thalamus.⁸ This area can also locate the exact position of the sensation; perceive the weight, shape, and texture of an object through touch and spatial recognition.

The inferior (meaning below) region is the lower-end part of the parietal lobe, and it concerns primarily with language, mathematical operations, body image, spatial attention, visuomotor, auditory processing, and involvement in the perceptions of emotions through facial expressions.

The superior (meaning above) region is the top part of the parietal lobe, which cares for spatial orientation and sensorimotor integration. The inferior and superior regions jointly are called the posterior (meaning rear) parietal cortex.

The precuneus part of the parietal lobe involves analysis, perception, and manipulation of visual patterns and images, episodic (long-term) memory retrieval, and first-person perspectives, i.e., the reflections of ego and self-consciousness. Damage in the front part of the parietal lobe on any side causes numbness and impaired sensation on the opposite side of the body. The affected person will have difficulty identifying a sensation's location and type (pain, heat, cold, or vibration). Damage to this lobe most often occurs due to vehicle crashes or falls.

Temporal or limbic lobe

This lobe is located near the temples of the head and toward the base of the central cerebrum region. It subdivides into superior, middle, and inferior areas and houses several critical components like the hippocampus and amygdala.

The temporal lobe receives information from the environment and creates a complex mind-body-environment interplay that constantly changes a person's subjective experiences. The temporal lobe is responsible for auditory processing, including perceiving sounds, assigning meaning to them, and remembering. Much of the audial work of the temporal lobe gets processed through the superior lobe,