The Neuroscience of Suicidal Tendencies

Suicide is as much complex as it is sad or unfortunate. How can someone take their own life? Why would someone want to end it all? These questions are puzzles that almost all behavioral-science domains have long sought answers to. Yet, there are always some pieces of the puzzle absent from the board, reminding us of the intricacy of it. Let’s find if the domains of Neurobiology and Neuropsychology have some of those answers.

Whether we find our answers or not, one thing is for sure that we are not at the wrong place to find them. Brain is where all our thoughts originate, all our emotions are felt, all our behaviors are conceptualized and all our actions emerge. This seat of electrochemistry is where we plan our life’s choices and this master then gets the corresponding actions executed. So what goes on inside brain when it conspires a silent sabotage at its own peril?

What can Neurobiology tell us about suicide?

While there are clinical factors (like hopelessness, aggression, impulsivity, pessimism or neuroticism) as well as neuroanatomical factors (e.g. people who display suicidal tendencies show abnormalities in ventromedial prefrontal cortex) responsible for suicidal tendencies, we will keep the scope of this blog-post around the Neurobiological factors.

The resultant search will take us to the world of neurons, neurochemicals and nervous system; because, as author Catherine Offord says, in the pursuit of finding an explanation to suicide, the scientists have found two neurobiological systems at work.

The first one is brain’s stress pathways.

Scientists propose that suicide is actually a product of precipitation and predisposition. In other words, it takes place when factors such as ‘increased stress’ meet aspects like ‘family history’. To understand it, we will have to traverse through the biochemical pathways that regulate brain’s response to stress, and understand how they actually get altered in suicidal people.

For this, we will need to bring our attention to the HPA Axis (Hypothalamic-Pituitary-Adrenal Axis is the interactive system between Hypothalamus in the brain, pituitary glands at the base of the brain and adrenal glands just above kidneys). This system regulates release of the stress hormone ‘cortisol’. Cortisol was always a suspect due to its upregulation in clinical depression, but the suspicion got confirmed when, in the brains of people who died by suicide, researchers found higher concentration of Corticotropin-Releasing Hormone (CRH), which triggers the synthesis of cortisol and other glucocorticoids (a class of steroid hormones) involved in stress signaling.

In addition to dysregulation of HPA, some researches have even found that people who died by suicide have enlarged adrenal glands – the sites of cortisol production.

The second system is the neurotransmitters in brain.

Researchers have consistently found deficits in serotonin signaling (serotonin is a feel-good neurotransmitter that gets secreted in the brain) in the brains of people who die by suicide. This has made serotonergic system the prime neurochemistry-system being probed for clues about suicidality. Researchers have also found that levels of 5-HT1A (Serotonin’s main metabolite) in some regions of the cortex are higher in people who attempt or die by suicide. But there is a twist to it.

As John Mann, a psychiatrist at Columbia University, explains – Higher levels of 5-HT1A contributes to a deficit in serotonin signaling because the receptor is part of a neural feedback response that inhibits further serotonin release into synapses. So, in people who are suicidal, says Mann “the problem is not the capacity to make serotonin but . . . the capacity to use that serotonin”.

This is precisely the reason why the antidepressants of the genre of ‘selective serotonin-reuptake inhibitors (SSRIs)’ dampen the suicidal thoughts and behaviors by reducing the number and responsiveness of 5-HT1A receptors and thereby quieting the negative feedback loop that suppresses serotonin signaling.

What can Neuropsychology teach us about preventing suicide?

Let’s first complete the Neurobiological-loop.

Researches reveal that adverse experiences in early-life and negligent parenting, two of the major risk factors for suicide can have long-term effects on the first system responsible for suicidal tendencies – the HPA-axis function. In fact, in the hippocampi of individuals who succumbed to suicide and had a past of childhood abuse, researchers found reduced expression of the gene coding for NR3C1, a receptor that aids dampening of cortisol signaling.

Like the HPA axis, even the second system – the serotonin signaling – has also been found to be influenced by early-life adversity. Moreover, researches have even revealed that kids who were bullied had hypermethylation (an epigenetic control aberration) at SERT – a gene coding for a protein that aids reuptake of serotonin – compared with kids who weren’t. Bullied kids also showed blunted cortisol responses to stress, corroborating the connection between the serotonergic system and HPA functioning.

So eventually, it boils down to the ‘maintenance of balance’ in our HPA-axis system and the serotonergic system. So now let’s talk about how to ensure that. While there are many psychological approaches (like CBT, REBT, DBT etc.) for that, let me talk only about some natural commonsensical tips that have been backed by Neuropsychology:

Exercise daily, because it boosts the level of serotonin in your brain. Moreover, as much of the serotonin is produced in our gut, so optimize gut health. Spending time in the sunshine also helps increase serotonin levels, so do take out time to go out in the sun. Complex carbohydrates, such as apples, blueberries, carrots etc. also boost serotonin, so do maintain a healthy diet.

In addition to this, thinking, visualizing and imagining what makes you feel good also increases serotonin in your brain, so do take care of your thought patterns. Add to it the right amount (and pattern) of sleep, proper hydration, aversion to addiction, some meditation & yoga, and healthy relationships, and you get a recipe for maintaining just the right amount of cortisol level. So you see, at the end of it, it all boils down to ‘holistically balanced life’ to stop the urge of ending it prematurely.

Who says every blog-post about Neuroscience should end with culminating complex jargon! :-)


Dr. Sandeep Atre

‘Emotional & Social Intelligence’ Expert; and Founder of Socialigence ( – a venture specializing in the development of ‘Emotional & Social Intelligence’ through its online course rooted in Neuroscience and Psychology.

Author of two books – “Understanding Emotions Logically” and “Observing Nonverbal Behavior”