Student ID: 56086510
Title : Effects of caffeine on mental alertness
Introduction
The majority of people take their caffeine, the most widely used stimulant in the world,
mostly coffee, which is a drink that some people drink daily. There is evidence that caffeine
improves focus, memory, and psychical function. Caffeine-containing products also have an
effective inotropic and chronotropic impact on the cardiovascular system (Cappelletti, Daria,
Sani, & Aromatario, 2015). According to a research conducted in New Zealand, tertiary
students drink a high quantity of caffeine, with 99.1% utilizing it for keeping awake and
warm, 76.3% for coffee, 71.6% for tea, and 81.7% for chocolate, with coffee for being awake
and warm and tea for warmth and flavor (Stachyshyn, Wham, Ali, Knightbridge-Eager, &
Rutherfurd-Markwick, 2021). In fact, around 60 plant species worldwide contain caffeine,
which was first used in ancient South American drinks including guarana, yoco, and mate
(Barone, & Roberts,1984).
Additionally, alertness can be characterized as prolonged concentration and cognitive
function, which are impacted by a variety of brain and neurotransmitter systems. It is
evaluated using physiological methods and cognitive performance, considering sleep-wake
state shifts (Oken, Salinsky, & Elsas, 2006). Long work hours, little opportunity for sleep, and
shift work all contribute to the high rate of sleep loss and exhaustion among healthcare
workers, they employ caffeine to temporarily increase alertness and battle the effects of
sleep loss, its use helps healthcare personnel maintain performance levels throughout
lengthy shifts (Owens, 2007). However, relying in Caffeine can cause a side effect such as
insomnia, nausea, vomiting and anxiety (Grant, Kim, & Friedman, 2023). Highlights the need
for a cautious and balanced approach to caffeine use, advising medical professionals to give
equal weight to good sleep hygiene and moderation in caffeine usage.Thus, Adults who
moderately consume 400 mg of caffeine daily do not appear to be at risk for negative effects
like cardiovascular disease, women are advised to consume no more than 300 mg, and
children should not exceed 2.5 mg. Consuming more caffeine than this can lead to general
toxicity and cardiovascular effects ( Nawrot, Jordan, Eastwood, Rotstein, Hugenholtz, &
Feeley, 2003).With moderate dose, caffeine can increase exercise performance, it also
increases dopamine levels in the brain, which is associated to improved focus, alertness,
motivation, and reduction in fatigue symptoms (Meeusen, Roelands, & Spriet2013).
However, athletes using high dose caffeine supplementation experienced the highest
prevalence and magnitude of tachycardia/heart palpitations and negative effects on sleep
onset (de Souza, Del Coso, Fonseca, Silva, de Souza, da Silva Gianoni, & Claudino, 2022).
Based to the theory that claims caffeine doesn't directly improve behavior, withdrawal
causes deficits, although this is improbable given that caffeine affects behavior in both
animals and non-consumers. According to Smith (2021), which looked at the effects of
caffeine in withdrew volunteers and following a previous dosage, there shouldn't be any
effects from the second dose if the withdrawal theory is accurate.
The study has the hypothesis which stated that the caffeine helps to increase alertness. This
study compares the increased alertness of the caffeine-consuming of Tertiary students, the
caffeine’s products include coffee and decaf group to the control group, which does not
consume any caffeine. The decaf group contained lower caffeine dosage compared to coffee,
using whole response functional dynamics and brain approaches we assess the alertness of
the participants.
Method
The experiment had a total of 329 participants, however we only have clean data for 295 of
them because some of them failed to complete the full experiment. This experiment's
materials and equipment include a ruler, pen, paper, an individual to assist with the
experiment, and a Qualtrics survey. The variables include ruler distance (measured),
urn/type of drink (manipulated), age (measured), gender (measured), caffeine previous to
lab (measured), and perception of drink. The students were given a cup with labelled A and
B, the student filled up the cup from the percolator with the same label, afterwards, the
student drink the coffee or control while they mingled for 10 minutes. After 10 minutes, the
participants measured and recorded the reaction time of each student. To measure the
reaction time the experiment involves a participant holding a ruler with a zero-mark visible
on their thumb, and the participant's thumb is recorded using the top of their thumb. The
experimenter then releases the ruler, and the participant's response time is tested by
recording the number level from cm to 1 decimal place, repeated the process five times,
switching positions each time until everyone has participated. The researcher filled out a
survey with the data on their reaction times. The data was then imported into Excel, which
calculated the frequency, standard deviation, and mean for each participant. A graph was
then generated for each variable, and the hypothesis's significance was calculated.
RESULT
Table. The difference in means and p value of the three groups, coffee , decaf and control .
Groups
Mean Reaction time
Standard Deviation
Coffee
162.70
21.99
Control
169.67
36.55
Decaf
160.49
35.23
The comparison between the reaction time mean of coffee and control group indicating that
coffee group has much faster reaction time. On the other hand, base statistical investigations
comparing the levels of alertness produced by coffee and decaf indicate that there is no
statistically significant difference between the two. This indicates that the two groups
possible have closely equivalent caffeine contents, leading to close similar levels of
alertness.
172.00
170.00
168.00
REACTION
166.00
164.00
162.00
160.00
158.00
156.00
154.00
Coffee
Decaf
Control
CONDITION
Figure 1 : Average Reaction Times across multiple groupings of conditions.
The study proposes that caffeine improves alertness as measured by reaction times. The
participants were split into three groups: decaf coffee, normal coffee, and a control group.
The reaction time of decaf was substantially quicker compared to both of the control and
coffee groups, indicating a placebo effect considering decaf contains less caffeine than
coffee. Further investigation may be required to see how other factors influence the
outcome. However, when comparing the reaction times of coffee and control, coffee has a
faster reaction time than control, supporting our hypothesis that caffeine enhances
alertness, whereas the control group has the slowest reaction time. In general, our results
suggest that caffeine increases alertness.
Discussion
This research aims to explore how caffeine affects people's alertness by comparing the
reaction speeds of caffeine-consuming participants to those of the control group. The results
corroborate the idea that caffeine increases alertness, as seen by the considerably quicker
reaction times in the caffeine-consuming groups (regular and decaf) when compared to the
control group. Remarkably, the decaf group had fastest reaction times than the coffee
and control groups, pointing to the potential for a placebo effect.
The outcome adheres to the findings of literature showing that people who expect the
treatment's outcome experience the placebo effect. In addition, it implies that indicators
linked to caffeine, including the taste and smell of coffee, can increase psychological
responses and, as a result of pairing, may elicit unreliable reactions (Flaten, Aasli, &
Blumenthal, 2003). The trend emphasizes the impact of belief on cognitive function and
raises the possibility that coffee's flavor, aroma, and ritual might boost attentiveness.
However, others studies have revealed that the benefits of decaf coffee may come from noncaffeinated ingredients including antioxidants and phytochemicals, which may improve
alertness and brain function even in the absence of caffeine ( Monjotin, Amiot, Fleurentin,
Morel, & Raynal, 2022).
Furthermore, participants who drank caffeinated coffee demonstrated an important
advancement in their performance, validating the widely recognized benefits of caffeine in
cognitive activities. In support with that, according to Smit and Rogers (2000), the amount of
caffeine consumed influence's cognitive function; a lower intake causes thirst, while a higher
intake improves performance. Frequent caffeine users are tolerant of thirst but not of the
effects on performance or mood. By blocking adenosine receptors, caffeine raises levels of
neurotransmitters like norepinephrine and dopamine, which promotes concentration and
fast reaction times (Zheng, 2023). These results resonate the previous studies that have
documented across sports and exercise, the study found that caffeine ergogenicity may be
greatly influenced by psychological variables related to oral caffeine intake, possibly even
more so than caffeine pharmacology (Shabir, Hooton, Tallis, & Higgins, 2018). The Decaf
coffee is a good substitute for individuals who need to concentrate, professionals, or
students because it provides the same cognitive benefits as caffeine without the side effects
of anxiety or sleep disruptions because of the lower dosage of caffeine decaf coffee have
compared to regular coffee. Additionally, research suggests that decaffeinated coffee may
lower blood pressure somewhat when compared to normal coffee; however, the greatest
effects are achieved when tea polyphenols, which do not include caffeine, lower blood sugar
levels from 150 to 133 mmHG (Wedick, Brennan, Sun, Hu, Mantzoros, & van Dam, 2011).
The study's limitations include the possibility of a placebo effect, in which individuals with
awareness of their coffee consumption may have become more attentive owing to their
expectations about the effects of the beverage. This might distort the results, particularly in
the group that drank decaf coffee. Other than the placebo effect, further study may
investigate other factors that might potentially participants' performance may also be
affected by other testing-related factors, such as overall hydration levels or the quality of
their previous sleep. Significant insights could also be gained by examining these effects in a
variety of populations, such as those with differing baseline levels of alertness and caffeine
tolerances.
To conclude, the study result which reveal that variables other than caffeine may affect
alertness and cognitive function, include the decaf group's unexpectedly reliable
performance. It encourages more study in this area by highlighting the psychological
consequences of the routine of drinking coffee and the potential advantages of coffee's noncaffeinated ingredients.
Reference
Stachyshyn, S., Wham, C., Ali, A., Knightbridge-Eager, T., & Rutherfurd-Markwick, K. (2021).
Motivations for caffeine consumption in New Zealand tertiary students. Nutrients, 13(12),
4236.
Barone, J. J., & Roberts, H. (1984). Human consumption of caffeine. In Caffeine: Perspectives from
recent research (pp. 59-73). Berlin, Heidelberg: Springer Berlin Heidelberg.
Cappelletti, S., Daria, P., Sani, G., & Aromatario, M. (2015). Caffeine: cognitive and physical
performance enhancer or psychoactive drug?. Current neuropharmacology, 13(1), 71-88.
Grant, S. S., Kim, K., & Friedman, B. H. (2023). How long is long enough? Controlling for acute
caffeine intake in cardiovascular research. Brain Sciences, 13(2), 224.
Oken, B. S., Salinsky, M. C., & Elsas, S. (2006). Vigilance, alertness, or sustained attention:
physiological basis and measurement. Clinical neurophysiology, 117(9), 1885-1901.
Owens, J. A. (2007). Sleep loss and fatigue in healthcare professionals. The Journal of perinatal &
neonatal nursing, 21(2), 92-100.
Nawrot, P., Jordan, S., Eastwood, J., Rotstein, J., Hugenholtz, A., & Feeley, M. (2003). Effects of
caffeine on human health. Food Additives & Contaminants, 20(1), 1-30.
Meeusen, R., Roelands, B., & Spriet, L. L. (2013). Caffeine, exercise and the brain. Limits of human
endurance, 76, 1-12.
de Souza, J. G., Del Coso, J., Fonseca, F. D. S., Silva, B. V. C., de Souza, D. B., da Silva Gianoni, R.
L., ... & Claudino, J. G. (2022). Risk or benefit? Side effects of caffeine supplementation in
sport: a systematic review. European journal of nutrition, 61(8), 3823-3834.
Smith, A. (2021). Caffeine and long hours of work: Effects on alertness and simple reaction
time. World Journal of Pharmaceutical and Medical Research, 10(2), 79-89.
Flaten, M. A., Aasli, O., & Blumenthal, T. D. (2003). Expectations and placebo responses to caffeine
associated stimuli. Psychopharmacology, 169, 198-204.
Smit, H. J., & Rogers, P. J. (2000). Effects of low doses of caffeine on cognitive performance, mood
and thirst in low and higher caffeine consumers. Psychopharmacology, 152, 167-173.
Zheng, S. (2023). Mechanism of Caffeine and Challenges of Caffeine Dependence. Highlights in
Science, Engineering and Technology, 80, 71-76.
Shabir, A., Hooton, A., Tallis, J., & F. Higgins, M. (2018). The influence of caffeine expectancies on
sport, exercise, and cognitive performance. Nutrients, 10(10), 1528. Shabir, A., Hooton, A.,
Tallis, J., & F. Higgins, M. (2018). The influence of caffeine expectancies on sport, exercise, and
cognitive performance. Nutrients, 10(10), 1528.
Monjotin, N., Amiot, M. J., Fleurentin, J., Morel, J. M., & Raynal, S. (2022). Clinical evidence of the
benefits of phytonutrients in human healthcare. Nutrients, 14(9), 1712.
Wedick, N. M., Brennan, A. M., Sun, Q., Hu, F. B., Mantzoros, C. S., & van Dam, R. M. (2011). Effects
of caffeinated and decaffeinated coffee on biological risk factors for type 2 diabetes: a
randomized controlled trial. Nutrition journal, 10, 1-9.