How Does Caffeine Hack Your Brain?

What is Caffeine and Why Does It Affect Our Brain?

Caffeine is an everyday product many adults use to stay awake or cram for exams, in fact 69% of Americans consume 1 caffeinated beverage daily . But what does caffeine actually do to our brain? First of all, caffeine is a commonly used psychoactive stimulant according to the National Centre for Biotechnology Information [NCBI] which many adults rely on for their daily life to maintain alertness, distributed in the form of coffee or tea. Caffeine is a bitter tasting substance found in many plants and it is part of a group of compounds called methylxanthines. Methylxanthines primarily stimulate the central nervous system or the CNS to give us the energetic feeling of taking caffeine.

Caffeine at a molecular level:

Studies described by the NCBI explains that the ability of caffeine to block adenosine receptors is highly important. But how does it occur? Well at a molecular level, neurons communicate through chemical signals which bind to specific receptors on their surfaces. Adenosine is a naturally occurring chemical in the brain that builds up during the day. At the synapse, adenosine binds to A1 adenosine receptors located on the axon terminals of a neurone, which reduces calcium entry. With less calcium available, calmodulin is not activated and CaMK activity decreases. This means less neurotransmitters are released contributing to slower neural signaling and feelings of tiredness. So when caffeine blocks adenosine receptors calcium entry is maintained. This allows calcium and CaMK to remain active contributing to higher levels of neural signaling having an opposite effect of feeling tired.

Effects on the Body and Brain:

Although caffeine gives you a boost of energy throughout the day acting as a positive benefit there are crucial risks. The benefits of taking caffeine can help with processing speeds and memory which improves cognitive function. In fact studies show that in 2020 people who drink 1-4 cups of coffee and green tea 3 to 10 cups are at lower risk of developing dementia. However even with these benefits an overdose of caffeine can lead to:

• Hallucinations

• Confusion

• Vomiting

A caffeine overdose can also lead to death in some particular cases most often in energy drinks. Even in caffeine withdrawal there are symptoms of:

• Headaches

• Anxiety

• Drowsiness

Caffeine withdrawal can be difficult because the body adapts to regular caffeine intake so a sudden change disrupts the balance. Caffeine does not only affect the brain, but can also influence several other body systems:

Digestive and excretory systems:

Caffeine can also impact the digestive and excretory systems, as caffeine increases the amount of acid in the stomach causing heartburn. Because caffeine is not stored in the body, it is broken down by the liver and is excreted through urine. This explains why caffeine consumption can lead to increased urination shortly after intake.

Circulatory and respiratory systems:

Caffeine is rapidly absorbed into the bloodstream and can increase blood pressure, possibly due to increased adrenaline release. For most people, this effect is short term and does not cause long term changes. However, in individuals with irregular heart rhythms this can increase heart activity and discomfort excessive amounts, caffeine can cause rapid or irregular heartbeats, breathing difficulties and in rare cases seizures.

In conclusion, caffeine is a widely used psychoactive stimulant that primarily affects the brain by blocking adenosine receptors and increasing neural activity to give a boost of energy when needed. While moderate intakes of caffeine can improve the cognitive function and processing speed of the brain, excessive consumption of caffeine can lead to risks such as harmful physical and psychological effects. Understanding the effect of caffeine is important, as it not only can improve alertness, but excessive consumption can lead to negative effects on both physical and mental health.