123 Mental Health and its Biological Basis

INTRODUCTION

According to the National Alliance on Mental Illness, approximately one in five American adults experience mental illness each year. That’s approximately 57.8 million people. Mental health is a complex and multifaceted aspect of human well-being that encompasses emotional, psychological, and social dimensions. What was once thought to be solely a consequence of upbringing and individual experience has now been proven to have biological underpinnings. Advances in neuroscience, genetics, and biochemistry have revealed how the brain’s structure, neurotransmitter activity, and genetic predispositions contribute to mental health and mental illness. Understanding this biological basis of mental health is crucial for advancing our knowledge and developing effective interventions.

This chapter explores the biological foundations of mental health, examining how the brain’s intricate network of neurons and neurotransmitters regulates mood, cognition, and behavior. It also delves into the genetic and environmental interactions that influence predisposition to mental disorders. A greater understanding of mental health’s biological influences can help develop more effective treatments. This exploration delves into the interconnected nature of mental health, examining its biological foundations and the implications for science, technology, and society.

Connection to STS

Advancements in neuroscience, genetics, and imaging technologies have enabled researchers to unravel the intricate connections between the brain and mental health. Scientific breakthroughs, such as the identification of specific genes associated with mental disorders and the development of neuroimaging techniques, contribute to a deeper understanding of mental health. The integration of technology in mental health interventions, such as virtual reality therapy and telehealth, reflects the dynamic relationship between science, technology, and society in addressing mental health challenges.

The Evolution of Mental Health Understanding and Treatment

Public perception of mental health disorders has evolved immensely since the times of skull drilling and asylums. In today’s society, 90% of Americans value mental and physical health equally, according to a 2015 survey by the American Foundation for Suicide Prevention (AFSP), the National Action Alliance for Suicide Prevention, and the Anxiety and Depression Association of America.

Ancient Perspectives and Treatments (6500 BCE – 2000 BCE)

Evidence of mental health perception through cave drawings and prehistoric skulls dates back as early as 6500 BC. During this time period, any deviations from ‘normal’ were deemed a consequence of supernatural influence.  Theories attributed mental illness to possession by evil or demonic spirits, punishment by gods, or even planetary gravitation and eclipse.

Trephination is one of the earliest treatment methods we have evidence of. It is the process of drilling a hole or removing a small area of the skull. It was believed to set evil spirits free and hence used to treat head injury and mental illness. Little is known about the exact reasoning behind this procedure due to insufficient evidence.

Chinese medicine introduced the concept of positive and negative forces within the body, called ‘yin and yang,’ around 2700 BC. In this culture, mental illness was attributed to an imbalance between the two forces. Trephination was believed to promote balance and allow vital airflow through the body.

Greek Physicians and Witch Hunts (400 BCE – 1700s)

Hippocrates rejected the idea of supernaturalism and proposed a concept known as humorism. Around 400 BCE, he suggested that mental (and physical) health was governed by the balance of four bodily fluids, or humors: blood, phlegm, yellow bile, and black bile. Illness was thought to be a result of imbalances and led to the rise of bloodletting as a treatment for mental illness.

Galen supported the concept of humorism. He also introduced some of the first psychogenic explanations for mental illness, as he believed mental abnormalities could be the result of psychological stress.  His ideas, however, were ignored for centuries as the common belief was that physical entities caused mental illness.

Beginning in the 13th century, mentally ill individuals (especially women) were persecuted as witches who were possessed. At the height of the witch hunts from the 15th to 17th century, Johann Weyer and Reginald Scot published De Praestigiis Daemonum (1563) and The Discoverie of Witchcraft (1584), respectively. These works challenged the ideas of witchcraft and magic, arguing that the real cause was mental illness. Both authors maintained that the witch trials were based on ignorance and superstition and advocated for more humane treatment of these women in their books. The Church’s Inquisition banned both of these pieces. Witch hunting did not decline until the 18th century.

The Beginning of Modern Mental Health Treatments (1500s – 1800s)

The establishment of hospitals and asylums for the mentally ill dates back to the 16th century.  Their purpose was not only to house those with mental health disorders but also to provide sanctuary to the homeless, unemployed, and criminals. However, war and economic depression skyrocketed the number of those individuals and widened the societal gap between the poor and the rich.

New confinement laws focused more on keeping the mentally ill separated from the public and less on helping or treating them. Following these laws, the responsibility to upkeep these facilities fell to the governments. The vast majority of inmates were housed against their will, stripped of their belongings and dignity. Society at the time viewed mentally ill people on the same level we do animals, and they were often exhibited to the public for a fee, much like a zoo.

Mental health was viewed somatogenically at the time, meaning physiological factors caused it, such as chemical imbalances or brain injury. Treatments were aligned with this view and, therefore, similar to remedies for physical illness. Purges, bloodletting, and emetics were all popular methods at the time. Additionally, there was a belief that instilling fear in the inmates would help restore the mind to ‘normal.’ Combine that with the animalistic view of the mentally ill, and you end up with the filthy, unlivable, and inhumane conditions of the asylums of the 16th and 17th centuries.

As the general public gained awareness of the horrors behind the walls of asylums, protests began rising in the 1700s, and the 18th and 19th centuries saw increases in more humane and logical views of mental illness. Italian physician Vincenzo Chiarughi (1759–1820) was one of the first to publicly take a progressive approach to mental health care in 1785. At St. Boniface Hospital in Florence, Italy, he removed patient restraints and promoted hygiene, recreation, and occupational training. Around the same time, French physician Philippe Pinel (1745–1826) and former patient Jean-Baptiste Pussin introduced traitement moral at La Bicêtre (1793) and the Salpêtrière (1795), emphasizing humane treatment through unshackling patients, improving living conditions, and encouraging purposeful activity (Micale, 1985). This transformation in treatment coincided with a shift to psychogenic views on mental health. Unlike somatogenic beliefs, viewing mental health psychogenically is most similar to how we know it today, resulting from psychological or emotional factors. This perspective continues to influence treatment methods today, such as cognitive-behavioral therapy and psychoanalysis.

Modern Perspectives on Mental Health

contemporary advances in mental health research

Research has elucidated the biological underpinnings of mental health, revealing the role of neurotransmitters, brain structure, and genetic factors in mental disorders. Neurotransmitter imbalances, alterations in brain regions like the amygdala and prefrontal cortex, and genetic predispositions contribute to conditions like depression, anxiety, and schizophrenia. Additionally, the gut-brain axis and the microbiome have emerged as significant factors influencing mental health. Understanding these biological aspects provides a foundation for targeted treatments and personalized approaches to mental health care.

MISSING VOICES

While scientific advancements have enriched our understanding of the biological basis of mental health, it is crucial to acknowledge the diversity of human experiences. Many mental health studies have primarily focused on certain demographics, potentially neglecting the unique challenges faced by marginalized communities. To foster inclusivity, it is essential to amplify the voices of underrepresented groups in mental health research, ensuring that interventions are culturally sensitive and consider diverse perspectives.

CONCLUSION

The biological basis of mental health intertwines with scientific progress, technological innovation, and societal dynamics. Unraveling the intricacies of neurotransmission, brain structure, and genetic influences opens avenues for targeted interventions. However, to address the complexity of mental health comprehensively, it is imperative to include diverse voices in research and consider the societal implications of emerging technologies. By embracing a holistic approach, we can pave the way for a more inclusive and effective understanding of mental health, bridging the gap between biology and the broader human experience.

AI disclosure statement

I used ChatGPT to help me find information about the biological basis of mental illness, as well as the history of mental health treatment. It provided summaries and suggested sources to support my research. I then incorporated additional sources I had gathered to refine and expand the chapter’s content.

OpenAI. (2025). ChatGPT [Large Language Model]. [https://openai.com/chatgpt](https://openai.com/chatgpt)

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