While many of us perceive ourselves as the architects of our own destinies, emerging scientific inquiry is illuminating the profound degree to which our conduct is shaped by our genetic makeup.
Advances in genetic sequencing now permit the detailed analysis of our unique genetic blueprint, a sequence comprising 3.2 billion DNA base pairs that serves as a fundamental design for our neural architecture and physiological structures.
This intricate genetic code elucidates the extent to which our behavioural patterns possess a substantial biological predisposition, potentially indicating a propensity for developing specific attributes or characteristics.
Scientific investigation has substantiated that heredity not only influences observable traits such as individuals’ stature, iris colour, or body mass, but also impacts our susceptibility to mental health challenges, our lifespan, cognitive abilities, and our inclination towards impulsive actions.
These inherent tendencies are, to varying extents, encoded within our genetic material – frequently involving the collaborative action of numerous genes.
The majority of these genes dictate the formation and functional operation of our brain’s neural networks during fetal development. It is now feasible to observe a developing infant’s brain in utero, even as early as twenty weeks gestation.
Discoveries have identified specific neural network differences within these developing brains that exhibit a strong correlation with genetic factors predisposing individuals to autism spectrum disorder and attention deficit-hyperactivity disorder (ADHD).
Furthermore, these genetic predispositions extend to conditions that may not manifest until much later in life, including bipolar disorder, major depressive disorder, and schizophrenia.
There is a growing recognition that predispositions towards more intricate behavioural patterns are similarly embedded within our neural architecture.
This includes influences on religious affiliations, the formation of our political ideologies, and even the composition of our social circles.
The Interplay of Nature and Nurture
Beyond the direct inscription within our DNA, other mechanisms exist through which our life experiences can be transmitted across generations.
The burgeoning field of “epigenetics” provides critical insights into the intricate relationship between innate predispositions and environmental influences.
This area of study focuses not on alterations to the genes themselves, but rather on the molecular modifications – or “tags” – acquired through life experiences that modulate gene expression.
A notable study from 2014 investigated epigenetic modifications in mice. These animals exhibit a positive response to the scent of cherries, activating a pleasure center in the brain that prompts foraging behavior.
Researchers intentionally associated this olfactory cue with a mild electrical stimulus, leading the mice to quickly associate the scent with the unpleasant sensation and anticipate it with aversion.
The investigation revealed that this learned association was inherited by subsequent generations. The offspring of these mice displayed an aversion to cherries, notwithstanding their direct exposure to the electric shocks.
The DNA within the sperm of the grandfather mice underwent structural alterations, effectively embedding a record of the experience within their genetic legacy.
While this research is still evolving and its applicability to humans requires further exploration, initial findings suggest that epigenetic modifications can indeed influence descendants of individuals who have endured profound trauma.
One study indicated that the sons of American Civil War prisoners experienced an 11% elevated mortality rate by middle age.
Another focused examination revealed that Holocaust survivors and their immediate offspring exhibited epigenetic alterations in a gene associated with their cortisol levels, a key hormone involved in the body’s stress response.
The overall picture is complex, but these findings imply that descendants may present with higher baseline cortisol levels, rendering them more susceptible to anxiety-related disorders.
The Realm of Free Will
It is crucial to recognize that our lives are not irrevocably predetermined by our innate genetic endowment, the DNA inherited from our parents, or generational memories.
Fortunately, avenues for adaptation and change remain open. Through the process of learning, new neural pathways are established. Consistent engagement with a learned skill or the repeated recall of a memory reinforces these connections, solidifying the information into lasting memory.
When a particular memory is frequently accessed, it can evolve into the default circuit for neural signal transmission, thereby transforming learned behaviors into ingrained habits.
Consider the act of riding a bicycle. This skill is not innate; rather, it is acquired through persistent effort, experimentation, and overcoming minor setbacks.
Analogous principles underpin both our perceptual faculties and our capacity for spatial navigation. We forge and strengthen neural connections as we traverse our surroundings, constructing our internal representation of the environment.
However, a significant caveat exists: prior learning can sometimes impede our acceptance of new information. Observe the following video demonstration – we possess an inherent bias towards perceiving familiar facial patterns in our environment.
This ingrained preference can lead us to disregard subtle contextual cues that indicate the object in question is actually the reverse side of a mask. Instead, we default to established neural pathways, generating the illusion of a face.
This perceptual phenomenon underscores the inherent difficulty in altering ingrained cognitive frameworks. Our sense of self and our expectations are largely constructed from past experiences. Modifying these deeply established mental structures can exact a substantial cognitive toll.
An Elegant System
In my most recent publication, The Science of Fate, I delve into this research, which addresses one of life’s most profound enigmas: our individual capacity for making choices.
From my perspective, there is a profound elegance in conceptualizing ourselves as complex, finely tuned biological mechanisms. External stimuli are processed by our unique neural systems, resulting in our observable behaviors.
Nevertheless, a considerable portion of the population may find it challenging to abandon the notion of unconstrained free agency. The concept of biological determinism, the assertion that human actions are solely dictated by innate factors, understandably engenders apprehension.
The implication that historical atrocities were perpetrated by individuals incapable of preventing their actions is deeply unsettling, as it raises the specter of their recurrence.
Perhaps an alternative perspective would involve viewing ourselves as individuals who are not inherently constrained by our genetic makeup.
By acknowledging the biological influences that shape our individual traits, we can potentially empower ourselves to better leverage our collective strengths and capitalize on our combined cognitive capabilities to foster positive societal change.
