Effect of Caffeine on Cognitive Functions
Coffee is arguably one of the most popular beverages globally. Statistics show that 80% of the total adult population in the United States consume caffeinated drinks (McLellan, Caldwell & Lieberman, 2016). Following its popularity and widespread use in altering physical behaviour such as sleep patterns, scientists have delved into research to understand its effects on human physiology. The immediate revelation has its ability to block adenosine receptors that are responsible for most cognitive functioning. Consequently, a debate has emerged on whether it is an enhancer or a hazardous element to human health. Despite the doubts and question marks, longitudinal empirical research has confirmed on more than several occasions that caffeine is an enhancer due to its effects on alertness, reaction time, attention, and vigilance.
Caffeine can improve the reaction time of an individual to an activity or action. Consuming caffeine in doses of 12.5-400 mg enhances an individual’s reaction time. Due to this reason, many athletes have adopted this concept by including caffeine in their energy drinks to bolster their reaction time to winning or starting a race. Kahathuduwa et al., (2016) posits that caffeine is also beneficial in improving the reaction to visual or simple recognition (p23). In the research, the authors experimented with 20 male volunteers to test the impact of 160mg of caffeine on reaction time on motor evoked potential (MEPs) (Kahathuduwa et al., 2016). The research revealed that caffeine improved their reaction time towards the activities significantly.
Besides improving reaction time, consuming caffeine enhances the vigilance of an individual. This vigilance is useful in situations where an individual need to sustain undistracted performance on tedious, boring, and lengthy tasks. Taking drinks rich in caffeine of about 200-300 mg increases the performance of a person for repetitive tasks (Cappelletti, Daria, Sani & Aromatario, 2015). It is for this reason that those involved in repetitive tasks consume coffee to remain vigilant. This idea is evident in long-distance truck drivers and overnight machine operators. The results of other research are consistent with the effects of caffeine on vigilance. For instance, a 2006 study revealed that consuming caffeine drink kept air force pilots vigilant throughout the nine-hour flight testing and simulations (McLellan, Caldwell & Lieberman, 2016). These results prove the importance of caffeine in improving individual vigilance.
Different levels of caffeine not only keep a person vigilant but also attentive. Attention is all about selecting and focusing on a specific task while suppressing the rest. Research by Oken et al., (2006), confirmed that caffeine levels above 40mg increase the attention level of individuals in specific tasks (McLellan, Caldwell & Lieberman, 2016). The results of the observed participants indicated that the caffeine level in their drink increased their speed and accuracy in performing the tasks. Biologically, it altered the adenosine receptor leading to actions such as rapid processing of visual tasks. Caffeine improves the execution of control tasks and aspects of attention, such as orientation and alertness. That makes caffeine a useful element and not a drug as opposed to claims that focus on the hazardous effect on human health.
Caffeine resembles the adenosine receptor and can be bound to the adenosine receptors of the brain cells. When the binding occurs, it results in drowsiness and depresses the central nervous system, thus slowing down the activity of the nerve cells and promoting relaxation. The user feels more relaxed after taking up a cup of coffee. On the contrary, if caffeine molecules replace adenosine, it lumps the sleep-inducing actions of the adenosine and at the same time, speeds up the activities of the nerve cells. It makes an individual feel temporarily awake and more energetic.
Despite the positive cognitive effects of caffeine on the human body, plausible arguments exist on its adverse impacts. Some research (Terry & Phifer, 1986) have established that consumption of caffeine above 100mg leads to loss of memory of words (McLellan, Caldwell & Lieberman, 2016). However, more recent research findings have yielded different results, with most establishing no correlation between its consumption and memory retention. Therefore, it is an effective enhancer for alertness, vigilance, reaction time, and attention. People should not be hesitant to consume it for fear of ruining their health.
References
Cappelletti, S., Daria, P., Sani, G., & Aromatario, M. (2015). Caffeine: Cognitive and
Physical Performance Enhancer or Psychoactive Drug?. Current Neuropharmacology, 13(1), 71-88. doi: 10.2174/1570159×13666141210215655
Kahathuduwa, C., Dassanayake, T., Amarakoon, A., & Weerasinghe, V. (2016). Acute
effects of theanine, caffeine, and theanine–caffeine combination on attention. Nutritional Neuroscience, 20(6), 369-377. doi: 10.1080/1028415x.2016.1144845
McLellan, T., Caldwell, J., & Lieberman, H. (2016). A review of caffeine’s effects on
cognitive, physical, and occupational performance. Neuroscience & Biobehavioral Reviews, 71, 294-312. doi: 10.1016/j.neubiorev.2016.09.001