Mental health issues have been found to have their roots in our biology, environment and cognition. Some mental health concerns have a genetic component, some may be caused by the circumstances that we find ourselves in, while some may be caused due to problems with the way we perceive events.
Focusing on the biological aspect in our last article, we explained what neurotransmitters are. The most important takeaway is that neurotransmitters are tiny chemicals, who’s changing levels have an impact on both our physiology and our behaviour.
Research has shown that neurotransmitters impact several mental health conditions. The way this happens is if the levels of the neurotransmitters fluctuate in an “abnormal” way, it can cause a mental health condition or prolong it.
Mental illnesses or disorders such as depression, anxiety, drug abuse and addiction, schizophrenia, Alzheimer’s disease and Parkinson’s disease have been found to be linked to neurotransmitters. Though more research is needed to find its precise function, some of the neurotransmitters that have an impact on our mental health are;
Norepinephrine is responsible for vigilance, attentiveness, alertness and arousal. It is found to be involved in sexual behaviour and control of appetite. Drugs that can change the levels of norepinephrine can alter mood levels. This is why lithium is prescribed to elevate the mood of patients with depression and bipolar disorder. The stimulating effects caused by recreational and prohibited drug usage occurs due to interference with norepinephrine function.
The reason Dopamine is so well-known is that it involves rewards, reinforcement and happiness. However, it is also responsible for several other important functions such as movement, attention, learning, regulation of motivation, emotional pleasure and the ‘desirable’ component of reward.
Due to these aspects, dopamine is linked to the reinforcing effects of drugs that people tend to abuse. Drugs can increase or decrease dopamine production or mimic dopamine’s function. Prolonged abuse could lead to addiction; increased dependence, on these drugs as the brain is now used to excess amounts of dopamine.
Low levels of dopamine are a cause for ADHD (Attention Deficit Hyperactivity Disorder) because of its involvement in the regulation of motivation and emotional pleasure.
Overactivity of brain cells that produce dopamine has been speculated to be a cause of Schizophrenia. Schizophrenia is a mental disorder that is characterised by hallucinations, delusions and distorted thinking. These symptoms can have a very negative impact on a person’s ability to function and lead a “normal” life.
The degeneration of dopamine-producing brain cells causes Parkinson’s disease which results in tremors, the rigidity of limbs, poor balance, and difficulty moving.
Fortunately, drugs have been developed to change the levels of dopamine as desired. This allows for the treatment of these mental health issues and improves the quality of life.
Acetylcholine (ACh) plays a key role in the formation of new memories. When neurons that produce acetylcholine degenerate, the levels of this neurotransmitter in our bodies decrease. This results in a memory disorder called Alzheimer’s disease. Alzheimer’s disease is a neurodegenerative disorder, where memory loss occurs. The lower the production of ACh the more serious the memory loss.
GABA or Gamma-Aminobutyric Acid can be a cause of aggravation or can act as a relaxant based on the levels produced. An abnormality with GABA has also been linked to epilepsy. Drugs that reduce GABA activity can cause convulsions in high enough doses. While drugs that promote GABA activity can have a tranquillizing effect, which is why they are used to treat anxiety disorders, promote sleep, reduce seizure activity, produce muscle relaxation, and general anaesthesia (in some cases).
Serotonin plays a very important role in the regulation of mood. Low levels of serotonin have been found associated with feelings of depression. But, Serotonin has complex behavioural effects. Not only does it affect the regulation of mood but also the regulation of pain and control of eating, sleep, arousal and dreaming. It has also been found to play a role in nausea and vomiting. Drugs that can increase levels of serotonin have been helpful in treating mental disorders such as depression, anxiety, obsessive-compulsive disorders, and Bulimia (an eating disorder involving binging and purging). SSRIs (Selective Serotonin Reuptake Inhibitors) are used as antidepressants because they decrease the natural destruction of serotonin. Another drug that increases serotonin levels and reduces the destruction of serotonin has been used as an appetite suppressant to treat obesity. Some drugs that affect serotonin have also been used to treat nausea or vomiting side effects of chemotherapy. Some hallucinogenic drugs can bind to serotonin neurons, causing vivid hallucinations. This effect can damage serotonin neurons and cause cognitive deficits.
Glutamate is a neurotransmitter that has an effect on learning and memory. Drugs that can impair glutamate functioning have been found to weaken plasticity (the ability for the brain to form new connections and new neurons) and some forms of learning. Glutamate abnormality has been found to be implicated in schizophrenia, Alzheimer’s disease, strokes and even epileptic seizures.
We have Endogenous Opioids in our brain which are present for pain reduction. Endogenous Opioids have an effect on rewards and reinforcement which explains why people abuse opiates leading to an addiction. Fortunately, there is a drug produced that is used to clinically reverse opiate intoxication which has saved the lives of many drug abusers who could have died of an opiate overdose.
So now you know!
We have now established that our mental health can be influenced by tiny chemicals in our brains. When people dismissively say mental health issues are “all in your head!”, they don’t realize it, but they might be onto something. Dr Erik Kandel, psychiatrist and Nobel Laureate, says
All mental processes are brain processes, and therefore, all disorders of mental functioning are biological diseases. The brain is the organ of the mind. Where else could mental illness be if not the brain?
Dr Erik Kandel, (Weir, 2012)
So, you now have ammunition for when people ignorantly say that mental health issues are “all in your head!”. Showing them that mental illnesses are in fact chemically influenced brain disorders can de-stigmatise mental illnesses immediately.
References
- Carlson, N. R. (2013). Physiology of behavior (11th ed.). Pearson.
- Nolen-Hoeksema, S., Fredrickson, B., Loftus, G. R.; Lutz, C. (2014). Atkinson; Hilgard’s: introduction to psychology. Cengage Learning.
- Weir, K. (2012, June). The roots of mental illness. Monitor on Psychology. https://www.apa.org/monitor/2012/06/roots.
Written by Peehu Jain, Art work and Editing by Rahat Lookmanji
