Caffeine: Cognitive Enhancer or Psychotropic Drug
By: Sai Srihaas Potu
Caffeine use is increasing worldwide. The underlying motivations are mainly concentration and memory enhancement and physical performance improvement. Furthermore, caffeine abuse and dependence are becoming more and more common and can lead to caffeine intoxication, which puts individuals at risk for premature and unnatural death. The use of caffeine to stay awake and alert is a long-standing habit.
Coffee is the most popular beverage after water and is consumed worldwide in daily amounts of approximately 1.6 billion cups, which is quite an impressive figure. The stimulant effects of caffeine on the body have been known for centuries, however, scientists have just discovered that caffeine is a cognitive and physical performance enhancer that can improve a person’s long term memory.
Caffeine is a stimulant drug that can increase awareness by suppressing the chemical associated with sleep. When adenosine levels are low in the brain and spinal cord, the body sends a chemical signal which indicates that it is time to shut down the body and relax. There are several different adenosine receptors throughout the body, and caffeine most affects the A1 receptor. When a substantial amount of caffeine is ingested it works its way toward your body’s adenosine receptors and mimics the effects. In other words, caffeine tricks your body into thinking that it's not yet time for sleep by acting like adenosine.
In recent years, numerous studies have proven that caffeine can heave significant health benefits. One study in particular analyzed the effects of caffeine on people right after a learning session. The researchers studied how a caffeine dosage affected the participant’s long-term memory.
The investigators analyzed 160 participants aged between 18 and 30 years. On the first day of the study, the participants were shown pictures of different objects and were asked to identify them as indoor or outdoor items. Soon after this task, they were randomized to receive either 200 mg of caffeine in the form of a pill or a placebo tablet. The next day, the participants were shown the same pictures as well as some new ones. The researchers asked them to identify whether the pictures were new, old, or similar to the original pictures.
From the results, the researchers were able to determine that the people who ingested caffeine were better at identifying similar pictures, compared with the participants who took the placebo. However, both of the groups were able to successfully distinguish between the new and the old images. Subsequently, the researchers repeated the study but used 100 and 300 mg doses of caffeine instead. They concluded that a dose of at least 200 mg is required to observe the enhancing effect of caffeine on the consolidation of memory.
The investigators say there are many possibilities as to how caffeine may enhance long-term memory. For example, they say it may block a molecule called adenosine, preventing it from stopping the function of norepinephrine, a hormone that has been shown to have positive effects on memory. However, the researchers noted that further studies need to be conducted in order to better understand the potential benefits and risks of caffeine and whether or not it is a cognitive enhancer.
Caffeine’s psychological effects are also responsible for its widespread use, as they can provide energy and improve cognitive skills. They are a direct result of the caffeine-induced chemical activation of different neuronal pathways through alterations in a neurotransmitters’ release. These effects can cause both psychological and physical dependence. After prolonged use of caffeine, a person’s withdrawal can lead to addiction and other tolerance mechanisms. Subsequently, the use of caffeine also has a substantial effect on the cardiovascular system as prolonged use can lead to acute and chronic cardiovascular diseases.
In recent years caffeine use has increased, especially among young people, due to the wide diffusion of caffeinated beverages advertised as energy drinks. Despite the wide diffusion of caffeine in the form of drinks, foods, and medications, death from acute intoxication is relatively rare and is mostly caused by voluntary or involuntary ingestion of tablets containing pure caffeine in high concentrations. Although variable amounts of caffeine are contained in coffee, tea, and other drinks, it is difficult to reach lethal doses of caffeine exclusively through one of these products.
While moderate consumption of caffeine is unlikely to produce harmful effects in most people, reactions to the stimulant depend on highly individual factors, such as genetics and accompanying lifestyle choices. People should be mindful that they are consuming a psychoactive substance when they use caffeine. Until further research is conducted, we will never know the true psychological and neurological effects that caffeine will have on our bodies.
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