In order to understand our behaviour it is necessary to consider the make-up of
the brain. For decades psychologists maintained that once the brain’s physical connections
were completed during childhood, the brain had become hardwired and remained like
that for life. Now, thanks to the latest imaging technologies, the concept of ‘neuroplasticity’
(the brain’s ability to change), and brilliant clinical research, we see that this
is, in fact, not the case and that human development is a continuous, unending process.
The key to individuality, however, is not to be found in the overall organisation
of the brain, but rather in the fine tuning of the underlying networks. In particular,
it is about the balance between our natural, instinctive reactions and our considered
responses to everyday situations.
PRISM looks at the structure and function of the brain,
and especially at the differences between the brain’s hemispheres, not only in terms
of attention and flexibility, but in attitudes to the world. It is a well-established
fact that there are obvious, undisputed differences in the shape, size, neuronal
architecture, neurochemistry and neuropsychology of the brain’s two hemispheres.
It seems obvious to ask: what does all that mean? The difference lies not in what
they do, but how they do it.
The reason we human beings have two hemispheres is that we need two views of the
world. Without the right hemisphere, we would be socially and emotionally insensitive,
and have an impaired understanding of beauty, art etc. Effectively autistic, we
have no sense of the broader context of experience. Meanwhile, without the left
hemisphere, we would struggle to bring detail into focus.
That the two hemispheres interpret and create the world differently, with different
modes of attention, different priorities and different values emerged in the 1960s
and ’70s. Over time, scientists discovered that each so-called ‘function’ was carried
out in both hemispheres, not one. For example, it is pointless searching for one
brain area that does mathematics. There are different aspects of maths, for example,
quantity and number. There are two types of number we can read - number words (‘seven’)
and numerals or digits (‘7').
The processes required to perform exact calculations reside in the left hemisphere,
in the parietal lobe. A different region of the brain, in the right hemisphere,
underlies approximation of number. People generally show high correlations between
mathematical ability and spatial ability in aptitude tests. In other words, people
who have very good spatial ability - who have a good sense of direction - often,
but not always, have good mathematical skills as well.
Also, the right hemisphere is unable to identify written numerals such as ‘12 -
6'. The right hemisphere knows that 6 is less than 8, but this knowledge completely
disintegrates for the word ‘six’. Neither can the right hemisphere alone name digits
and perform arithmetic.
The left hemisphere can add up
numbers 2 plus 2, but the brain finds this impossible if the sum is shown solely
to the right hemisphere. The left hemisphere can do multiplication whereas the right
hemisphere cannot. The right hemisphere approximates while the left hemisphere calculates.
Similarly, although language resides in the left hemisphere in most people for people
who are right-handed, it is not usually the case for left-handers - language is
normally housed in both hemispheres in these people.
Fundamentally, PRISM is about our attention to the world;
how we see and respond to our environment, including the people in it. More accurately,
it is about our perception, or representation, of our environment. Our attention
can either be broad or narrow.
The right hemisphere is responsible for broad attention, the left hemisphere for
narrowly focused attention. Although the brain is split into hemispheres, it is
a single, integrated, highly dynamic system. Events anywhere in the brain are connected
to, and potentially have consequences for, other brain areas. As you read the words
on this page, you are using thousands of the 100 billion nerve cells that make up
your brain. The electrical firings and chemical messages running between these cells,
called neurons, are what produce our thoughts, feelings and interactions with the
world around us.
The PRISM Model is a metaphor for how the brain’s functional
architecture and neural networks interact with brain chemicals such as glutamate,
dopamine, noradrenaline, serotonin, testosterone and oestrogen to create behaviour.
Modern neuroscience rests on the assumption that our thoughts, feelings, perceptions,
and behaviours emerge from electrical and chemical communication between brain cells.
On a broad level, the brain lends itself to partitioning, based largely on its anatomy.
All proposed divisions within the brain are, however, highly artificial and are
created in response to the human need to separate things into neat, easily understandable
units. We must always bear in mind, however, that the brain functions as a whole
and, with that caveat in mind, the PRISM quadrant model
provides us with a useful schema that we can refer to when we are visualising how
our brains are organised. It is, therefore, based on scientific principles and facts
which have been simplified into a workable model to facilitate understanding.
PRISM is intended to be a sort of beginner’s guide to
neuroscience. The neuroscientific language about the brain is extremely complex.
PRISM attempts, therefore, to simplify that language
so that it can be more easily understood. As a result, it contains many simplifications.
For example, when we say; the left hemisphere is responsible for this, or the right
hemisphere is responsible for that, it must be understood that in any one human
brain at any one time both hemispheres will be actively involved. No single part
of the brain does solely one thing and no part of the brain acts alone. All our
thoughts, emotions and actions are the results of many parts of the brain acting
together. When reading this section, it is important to bear in mind that the brain
functions as the result of the dynamic interaction between many different systems,
at different levels of organization, each operating according to its own rules.
The adult brain weighs about 3 pounds (1.4 kg) and contains about one trillion brain
cells, 100 billion of them neurons. This is a gigantic number of cells. Neurons
have both short and long fibres that contact the bodies of other neurons, and there
are about one million billion connections between cells in the brain.
100 billion cells is such a large number, it is hard to imagine. One million is
1,000 times 1,000, the population of a very large town, for example. One billion
is 1,000 times one million. The number of connections in the human brain is much
bigger than the whole earth's population, which is about 7 billion.
Most of who we are is the result of the interaction of our genes and our experiences.
In some situations the genes are more important, while in others the environment
is more crucial. Genes set boundaries for human behaviour, but within these boundaries
there is immense room for variation.
The brain is split down the middle from front to back into two blocks known as hemispheres.
The left hemisphere controls the right side of the body and the right hemisphere
controls the left side of the body.
While it is true that one hemisphere dominates over the other in terms of our experience
of the world and our actions, both sides of the brain work together in almost all
situations, tasks and processes. In other words, people are not right or left brained,
they use both sides of the brain.
The two hemispheres are linked by a ‘bridge’, known as the corpus callosum has an
'excitatory' function i.e. it enables the two hemispheres to communicate with each
other. However, the main purpose of a large number of these connections is actually
to inhibit - in other words to stop the other hemisphere interfering inappropriately.
The corpus callosum’s excitatory and inhibitory roles are, therefore, both necessary
for normal human functioning.
Each hemisphere can be divided into four individuals chunks, known as lobes. The
lobes are called frontal (front), temporal (side), parietal (top), and occipital
(back). The right hemisphere (Green and Blue on the PRISM
model) is predominantly associated with empathy and novelty. The left hemisphere
(Gold and Red on the PRISM model) is predominantly associated
with systemizing and routine.
‘Empathizing’ is the drive to identify another person’s emotions and thoughts, and
to respond to them with appropriate emotion. For example, the right hemisphere helps
us pick up on nonverbal cues in speech and gesture as well as in facial expressions.
‘Systemizing’ is the drive to analyse, explore and construct a system. Systemizing
intuitively figures out how things work, or extracts the underlying rules that govern
the behaviour of a system.
The right hemisphere is interested in others as individuals. Self-awareness, empathy
and identification with others are largely dependent upon the right hemisphere.
On the other hand, the left hemisphere is not impressed by empathy. Its concern
is with maximising gain for itself and its driving value is practical usefulness.
The left hemisphere is competitive and its concern, its prime motivation, is power.
The right hemisphere is particularly well equipped to deal with passions, sense
of humour, metaphoric and symbolic understanding, and all imaginative and intuitive
While a lot of attention has been focused in the press on the interaction between
the right and left hemispheres, it is also important to focus on the interaction
between the front and the back of the brain. The back of the brain (Red and Blue
on the PRISM model) is the sensory or input half, which
receives input from the outside world and sorts, processes, and stores all of our
sensory representations. This area is, however, not simply a site for processing
sensory information. It is also the region of cortex for associative processes,
where information from the various senses is bound together for higher order processing.
To view the brain’s key structures
click here >>
In the front of the brain, the cortex is devoted to the processing of motor programs
or output; we use this area to react to the input data from our senses. It is here
we plan, create strategies, and create our responses to the world, and it is this
area that has been adapted for use in abstract thinking and planning. The frontal
lobes perform the most advanced and complex functions in all of the brain, the so-called
They are linked to intentionality, purposefulness, and complex decision making.
Motivation, drive, foresight, and clear vision of one's goals are central to success
in any walk of life. The frontal lobes play a critical role in dealing with novelty.
A novel task activates predominantly the right prefrontal cortex. As the task becomes
familiar, the overall level of activation drops and shifts from the right to the
left prefrontal regions.
Underneath the cortex lies the limbic system which is involved in the generation
of emotions. The limbic system is made up of several pieces including the hippocampus
(memory), the amygdala (emotion, including fear) and the hypothalamus (the body’s
thermostat), Also, in moments of emergency the limbic system commandeers the rest
of the brain to protect us from harm.
Other items, such as the anterior cingulate gyrus, directs our inner response to
others and keeps us willing and interested in being with them. The orbitofrontal
cortex is the error catcher and with its partners, the anterior cingulate and the
ventromedial cortex of the frontal lobe, is crucial for empathy and evaluation of
the genuineness of the words and intentions and comments of others.
The human brain remains the most complex item in the known universe. It has been
described as follows by Professor Robert Ornstein:
“The brain regulates all bodily functions; it controls our most primitive behaviour;
eating, sleeping, keeping warm; it is responsible for our most sophisticated activities;
the creation of civilisation, of music, art and language. Our hopes, thoughts, emotions
and personality are all lodged somewhere in there. After thousands of scientists
have studied it for centuries, the only word to describe it remains: “amazing”.
The discoveries of neuroscience have shifted the paradigm of how the brain works
and, as a result, they are challenging our beliefs about human behaviour and potential.
When it comes to business, the effect is nothing short of revolutionary. This isn’t
just about making use of a new management technique, model or practice. The latest
research goes right to the way we think about human behaviour, highlighting fundamental
flaws in our current approaches and providing new insights that challenge everything
we take for granted about ourselves and others.
Although the PRISM Model is based on the published works
of a wide range of experts within the neuroscience community, this should not be
taken to mean that any of those individuals necessarily advocates or supports the
content of the instrument.