The perpetual conflict between Nature and Nurture – whether our personality or psychological traits are defined by their genetic formulation or influences from our external environment – is one that is fundamentally incomprehensible. The widely accepted disparity between these two psychological media conceals their biological compatibility, which consequently culminates in the individual personalities we all possess. The view that human traits flourish almost exclusively from environmental influences was termed tabula rasa (or “blank slate”) by John Locke in the late 17th century, but as both “nature” and “nurture” factors are found to contribute substantially – and often inextricably – modern scholastic study combines the two in an indisputable balance.

Despite humans being inextricably similar to each other, demonstrated through our behavioural characteristics (such as in bipedality and gregariousness) and our psychological capacities (such as in abstract reasoning and social cooperation), DNA is fundamentally the determiner of our differences: differences that are characterised in variations in the physical landscape of our brains which mediate our innate-self and humanistic behaviours. Effectively, human beings are 99.9% similar to each other, but the minute difference that encapsulates our variations is simply caused by the phenotypic – observable – effects of our neural development.

Many artistic diagrams of human neural pathways or perfectly symmetrical brain structures could not be further from the truth: this is because they suggest that all neurones are of the same shape and size and are displayed randomly. In reality, neurones are laid out in highly organised microcircuits with variations in neural connections (excitatory or inhibitory) which culminate to form much larger brain systems; even with regard to physical brain shape, the asymmetric lop-sidedness of all human brains acts as a certification stamp of our ability to adapt. It is this genomic organisation – which varies minutely in each of us – that means genetic variation is inevitable. 

In order to investigate the significance of genes in determining our psychological traits, we can examine the varying disparities in the characteristics of identical as opposed to fraternal twins; whilst phenotypic similarities (appearance) are easily observable, mathematical determination demonstrates that identical twins have a much higher similarity in their psychological traits such as extraversion or IQ than fraternal twins, irrespective of their external environment. What this suggests is that our familial environment has little effect on altering or subjugating our innate characteristics but rather seeks to amplify our biological predispositions.

Suppose two identical twins were to witness the exact same event at any one moment, their subjective interpretations of their experience dictate their neuro-plasticity. In other words, one may feel cheerful, and the other distraught: the same experience does not generate a specific hormonal (emotional) response but crucially it is our innate predispositions’ interaction with our environmental experiences that can model our internal, emotional responses and in a much larger scale, shape the trajectories of our lives.

Interestingly, it is proposed that this understanding of the nature of our individual existences is effective in underlining the essence of many psychological states, such as political or sexual orientation, both of which may have elements that can be explained by our biological predispositions and neuro-environmental interactions.

Conditions such as Capgras (“Imposter”) Syndrome – sufferers have the irrational belief that someone they know or recognise has been replaced by an imposter – or Alien Hand Syndrome – where people experience their limbs acting seemingly without conscious control – are primarily conceived by the varying surface structures of the brain; such conditions both affect memory and severely alter your sense of reality, in a similar way to dementia and Alzheimer’s disease. References to the surgically originating “Split-Brain Syndrome” by the agenesis of the Corpus Callosum (nerve tract involved in connecting the two halves of the brain) further demonstrates that the physical architecture of our brain substantially influences our psychological traits.

From the beginning of humanity, mankind has been burdened with thought, we have toiled with controversy and have been sustained by an instinct for self-preservation. From birth, an individual possesses the psychological capacity to adapt to both physical and emotional situations, and collaborate with other individuals for the benefit of their community. The necessity of our individual selves to adapt and thrive in a constantly changing political, physical, and emotional landscape places our innate characteristics and external environment in a harmonious pairing, not in deleterious combat.

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