Creativity, innovation and connection have been preserved for cities and urban areas in the past centuries. This rapid urbanization process has had a huge impact on people’s mental health and well-being. Urbanization has caused a growing increase in noise, crowds, traffic, pollution and financial constraints. All of these overwhelming issues have led to our brains struggling to cope due to being in constant activation.

What chronic stress does to neural circuits

The brain has shown prolonged stress rewires its circuit. According to neuroscientific research, the neural architecture of the brain is delicate and can be disrupted by excess cortisol from the hypothalamic-pituitary-adrenal axis when triggered. This shrinks the hippocampus responsible for learning and memory, the prefrontal cortex becomes less effective in regulation of executive functions such as planning and decision-making, and the amygdala responsible for fear becomes hyperactive, making us more prone to anxiety and emotional reactivity.

These changes can manifest as memory lapses, scattered attention, and increased irritability. Depression and anxiety are a consequence to chronic stress as shown in studies. Nature Mental Health published study findings from 2025 showing income as a common urban stressor that affects mental health outcomes. Income inequality disrupted brain connectivity due to reduced cortical thickness.

Urban stressors and the African context

Rapidly expanding cities in Africa have it rough. In Nairobi, Lagos and Accra, there is a perfect combination of stressors that take a toll on its people: limited healthcare, limited access to green spaces, overcrowding, and a lack of infrastructure. Cumulative stressors such as food insecurity, adverse childhood experiences and social isolation predispose residents in the cities to anxiety and depression, especially the youth and young mothers according to longitudinal studies.

The biology of “always-on” pressure

So, what happens when our brains are constantly under pressure? The threat signals flood the system from domination by the amygdala because the prefrontal cortex activity is under a diminished vicious cycle. The brains ability to form new memories and adapt is eroded by suppression of neurogenesis of the hippocampus by cortisol. Over time, we become more impulsive, less focused, and more vulnerable to mood disorders.

Are the effects reversible?

There is hope. These changes can be reversed due to the plasticity of the brain. Chronic stress effects can be mitigated through regular physical activity, strong social networks, and mindfulness-based interventions. Access to nature reduces anxiety and rumination, restoring attention and relaxation according to EEG evidence.

A global issue, not a regional one

Chronic stress is not only an epidemic but a pandemic. Western cities contribute to the rising stress levels with soaring housing costs, digital overload and extensive working hours. There is consistency in the brains response to sustained stress levels across diverse cultures: altered connectivity in reward and emotion circuits. These accelerate makers of brain aging.

The takeaway

As our urban future unfolds, it’s essential to recognize that chronic stress is not just a psychological nuisance but a biological threat to our cognition and well-being. By designing cities with green infrastructure, affordable housing, reliable transport, and noise mitigation, we can create environments that support, rather than erode, our mental health. By understanding the mechanisms of chronic urban stress, we can build a better future for our brains and our cities.