Our lives are a constant stream of experiences played in our minds. Our waking and dreaming states can be clubbed into a single state of dream, while the dreamless sleep is where we get the experience of no-experience.
However, where is the mind? What are its constituents and how is it
produced?
The mind is a strange place, different from our bodies in construct.
However, it is the place where all our experiences are played. A nice analogy
to understand it will be that of the screen where all plays are orchestrated.
Limitations of this analogy however is that the screen and the plays on the
screen are two different entities, while the mind is nothing but a collection
of experiences, including the experience of no-experience. Another analogy to
understanding the mind is the concept of the space-time fabric in physics where
the actors of the universe play their roles. However, these are just analogies
to grasp the abstract nature of our minds. Strangely, it is as real as our
existence and as imaginary as the proverbial ghost.
We now know that experiences are codes stored in our memories and orchestrated
when neurons trigger those areas of the brain. Hence, the memory areas of the
brain should be a part that helps in creating our minds. We also know that our
thoughts are constructed through the stored memories, and we can control some
aspects of our experiences by thinking. Hence, the thought producing portions
of our cortex helps in creating and controlling our minds. We also think in
languages and hence the language producing and comprehending portions of our brains
are involved in creating our minds. Our hormones and emotions colour our
experiences and thus these areas are also involved in manipulating our minds.
We experience pain, hunger, taste, satiation, pleasure, and a host of emotions.
All these areas of the brain are directly related in creating our mind.
Finally, the external stimulus receiving areas of the brain (vision, taste,
sound, smell, and touch) creates the sensations of experience and therefore
these too should be the part that creates our minds. Thus, we see that a major
part of our brain is involved in synthesizing the complex array of experiences
that defines our minds. To the question of where our mind is, the answer is
simple, in our brain. It is distinct from the brain but a creation of our
brain.
How does our brain create these experiences that together
constitutes our minds? This is where we have no clue. We are not clear how the
experience filled mind is created, but we know that if parts of our brain are
damaged, then for ever we will not be able to create the associated
experiences. The approach that neuroscience is taking is identifying the areas
of the brain that gets triggered when a particular experience is felt. It has
been able to broadly identify neuronal masses that can be associated with a
particular type of experience, e.g., the occipital region of the brain is
activated during the sensation of vision, while amygdala activation is
associated with the experience of fear. However, why does the activation of
amygdala give us the experience of fear is still unknown. Neuroscience gives us
the correlation but not the process of creation of experiences.
The relationship between the brain and the mind is somewhat like that
of a computer hardware and the software running in it. We know for sure that
the computer hardware does not experience a software running in it but does our
brain experience our minds? Most probably, our brain does not experience our
mind. It only creates it. Surely the mind cannot be enjoying the experiences.
It is a collection of experiences. It cannot experience itself. Our bodies also
cannot be experiencing the experiences, they send sensory and other stimuli to
the brain that creates those experiences and stores them as codes for future
reference. Among the three probable candidates of the brain, the mind and our
bodies, the brain looks to be the only possible candidate to be enjoying the
experiences. Let us then assume it to be true that our brains create and
experience the experiences.
To understand the implications of the above assumption, let us analyse
a specific case, the experience of fear. We know from neurosciences that
stimulation of the part of brain called amygdala gives us the sensation of
fear. Now amygdala is a bundle of neuronal cell bodies which makes its axonal
projections to the ventromedial prefrontal cortex, the hypothalamus area,
hippocampus region and the nucleus accumbens. Neuronal cell bodies from these
regions in turn project their axonal fibres into other regions, e.g., the
ventromedial prefrontal cortex makes projections to dorsomedial prefrontal
cortex and the projections keep moving from one region to the other in a complex
network. The projections from the amygdala neuronal cell bodies are not limited
to the above-mentioned regions of the brain but these are some of the well-known
bundles of projections from the amygdala. The above-mentioned regions also
return their neuronal projections into the amygdala region. Now, when we say
that the amygdala is creating the sensation of fear, we mean electrical signals
in the amygdala region gets projected into other parts of the brain. Why
passage of electrical signals from the amygdala neuronal cell bodies to other
regions of the brain creates the sensation of fear is a mystery. However, when
we say that our brain experiences that sensation, we mean that these neurons
and their projections into various parts of the brain is experiencing the
sensations, because there is nothing more to our brains than the neuronal cell
bodies and their axonal projections. Assuming that our neuronal cell bodies and
their projections are experiencing the sensations is truly bizarre.
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