Motivation and emotion/Book/2014/Caffeine and motivation
What is the effect of caffeine on motivation?
Overview[edit | edit source]
"Even bad coffee is better than no coffee at all" - David Lynch
How does caffeine interact with us? For many people, the consumption of caffeine is an everyday necessity. These people take it to make themselves more alert, focused, awake and motivated to continue with their day. But many of these people would tell you if you asked them why do they pursue their coffee in the morning would be that they need it. They need it probably because of the significant impact that caffeine has on a persons everyday life and productivity, improving mood and attention is a pretty good way to start the day. But it also has an affect on our brains that is pretty similar to cocaine, in that it is moderately addictive.
Caffeine: What is it?[edit | edit source]
Caffeine is a naturally occurring molecule found in many varieties of plants (Nehlig, 2005). It has a very similar shape to the chemical found in the brain called adenosine (Fredholm, 1995). It is a psychoactive stimulatory drug and an antagonist to the adenosine receptors that has an active effect on our brain activity. Common side effects of caffeine consumptions are that it makes us more alert, awake, and increases our heart rate (Smith, Gupta & Gupta, 2006). Caffeine is the most consumed legal drug in the world (Smith, Gupta & Gupta, 2006). It is consumed through food and beverages, primarily through coffee, and is just about available to all ages, and there are fairly loose restrictions regarding the legal amount of caffeine that any food or drink can contain.
What effect does caffeine have on the brain?[edit | edit source]
Adenosine is the chemical that accumulates over time in our brain and binds to adenosine receptors while we are awake which gradually slows brain activity (Fredholm, 1995). In other words, it is the chemical responsible for making us tired and, through sleeping, the receptors are cleared of adenosine and the process starts again the next day. Caffeine interferes with this cycle as it is an antagonist to the adenosine receptors (Dawkins, Shahzad, Ahmed & Edmonds, 2011), meaning it can bind to the receptors that adenosine binds to, and has the opposite effect on our brains, speeding up our processing speed, making us more alert, more awake and more motivated to pursue whatever is on our minds. Caffeine has a half-life of about 6 hours, which means if you drink a standard cup of coffee that contains 150mg of caffeine, about 6 hours later, only 75mg of caffeine will remain in your system which means that you will only be feeling half of the initial buzz (Nehlig, 2005; Smith, Gupta & Gupta, 2006).
Over time, someone who consumes caffeine on a regular basis will find that they need a higher quantity of it in order to maintain the same effect of the initial or first dose (Fredholm, 1982). This is because our brains will grow more adenosine receptors in order to accommodate that it is not accumulating the chemical like it normally should be, therefore it builds a workaround from the caffeine doses thus the individual requiring more caffeine in order to counter the effect of the additional receptors (Boulenger, Patel, Post, Parma & Marangos, 1983; Fredholm, 1982). However, this means the more caffeine that someone consumes will increase the amount of adenosine receptors in their brain and therefore require more caffeine to maintain its efficacy, until that person stops consuming caffeine (Nehlig, 1999). Aside from effectively changing the structure of the brain, caffeine also blocks the reabsorption of dopamine in the prefrontal cortex which is what makes it mildly addictive, however this effect does not appear to be present so strongly in the nucleus accumbens, which is the brain structure that is mostly associated with addiction (Nehlig, 2005; Smith, Gupta, & Gupta, 2006). The consumption of enough caffeine also induces the production of adrenaline, also known as the fight or flight hormone, which as a component of caffeine consumption adds to the feeling of being alert and awake and is what also provides the cardiovascular effects felt by the consumption of caffeine (Nehlig, 2005; Smith, Gupta & Gupta, 2006).
How does caffeine effect motivation?[edit | edit source]
Caffeine's effect on our motivation is two-fold: what happens when we receive a dose of caffeine, and what happens when once we are accustomed to dosages, when that is taken away? Caffeine itself may actually not have a great influence directly on individual motivation (Boolani, Lindheimer, Low & O'Connor, 2014). Instead, caffeine influences other personal aspects such as improving mood and attention span, which is a more favourable context for any type of motivation to flourish. Therefore, when one consumes caffeine with the expectation that it will improve their motivation for a particular task, this is actually a secondary effect that stems from improved mood, attention, cognitive performance and probably the other physiological effects that caffeine has on the human body (Boolani, Lindheimer, Low, & O'Connor, 2014; Maridakis, Herring & O'Connor, 2009). Another secondary effect from caffeine is that it has been shown to enhance learning, since it improves attention and mood, learning and memory are more easily facilitated (Nehlig, 2005; Smith, Gupta & Gupta, 2006). It can be argued that this is the reason why so many people partake in the consumption of caffeine, for all of the beneficial effects it has on mood, cognitive performance, attention, wakefulness and the feeling of reduced fatigue (Maridakis, Herring & O'Connor, 2009). There should be no surprise after learning of these effects that so many people would claim that they need their daily morning coffee to start the day. Due to the half-life of caffeine, its depletion throughout the day is likely what would cause someone to reach for a second (or third, etc) cup of coffee or anything else that contains caffeine (Nehlig, 2005).
There is evidence that suggests that more motivation to consume caffeine can arise out of social situations, or even as a preference for taste over functionality (Graham, 1988). That is, it can be more easily predicted that people will drink coffee or tea for the sociability of it, or for the sensory experience of it, compared to people consuming these beverages in order to attain or maintain higher alertness and wakefulness. If these social instances occur frequently enough, a person may develop a moderate caffeine habit because of the effect that it has on our brain (Nehlig, Daval & Debry, 1992).
The other aspects that surround the subject of caffeine and motivation come from addiction, after all, caffeine is a drug (Nehlig, 2005). The motivation to acquire caffeine can become a habit, or a moderate addiction (Nehlig, 1999). To regularly consume caffeine is to reinforce a habit that the self may perceive as a necessity in order to function at a desirable level. In order to do this people must have that motivation to function at a level higher than they may currently be and the consumption of caffeine feeds this cycle (Nehlig, 2005). On the other hand, if someone abruptly stops their caffeine consumption, they may end up desperate for a dose as caffeine headaches and increased anxiety set in (Smith, 1987). With someone who is deficient in caffeine, the acquisition of it will usually quickly remedy the withdrawal effects, which may act as a greater reinforcer to the motivation to not miss out on a regular dosage (Nehlig, 2005; Smith, 1987).
Caffeine deprivation[edit | edit source]
When an individual who consumes caffeine regularly misses a dose or decides to abruptly stop, they may report some almost immediate withdrawal symptoms (Nehlig, 1999; Nehlig, Daval & Debry, 1992; Smith, 1987). The reported withdrawal symptoms are moderate; they are nothing like an individual would experience suffering withdrawal from any hard drug such as cocaine, heroin or amphetamines (Smith, Gupta & Gupta, 2006). The most immediate and familiar with regular caffeine users is the withdrawal symptom attributable to the deficiency of caffeine known as the caffeine headache (Smith, 1987). These headaches can present co morbidly with high anxiety, but they are typical occurance to those who may be considered heavy caffeine drinkers. After a number of weeks, the headaches cease and anxiety returns to normal (Smith, 1987). Other withdrawal symptoms include cardiovascular issues such a somewhat large but not too drastic change in blood pressure and heart rate, gastrointestinal issues - particularly with coffee as it has a stimulatory effect on the bowels, and overtiredness (Smith, Gupta & Gupta, 2006; Smith, 1987). The overtiredness occurs due to the increased number of adenosine receptors that the brain has developed in order to deal with the caffeine. If caffeine consumption stops, then adenosine in the brain begins to bind to the extra receptors, which results in the individual feeling more fatigued then they were before they even began consuming caffeine (Boulenger et al., 1983; Fredholm, 1995; Fredholm, 1982).
Can you have too much caffeine?[edit | edit source]
It takes a lot to overdose on caffeine, so much so that it is physically impossible for a human to do so (Fredholm, Bättig, Holmén, Nehlig and Zvartau, 1999; Nehlig, 2005; Smith, Gupta & Gupta, 2006). The lethal dose of caffeine is considered to be 150mg per kilogram an individual weighs, this means that someone who weights 60 kgs would need about 9,000mg of caffeine to have a fatal effect. The average cup of coffee contains about 150mg of caffeine, so someone who weights 60 kgs to overdose on caffeine would need to consume roughly 60 cups of coffee, all at the same time which is physically impossible to fit into the human stomach (Nehlig, 2005; Smith, Gupta & Gupta, 2006). Well before this point, someone consuming that much caffeine would suffer all sorts of sensory hallucinations, mania, and many other adverse effects before succumbing to any fatal effect (Fredholm, Bättig, Holmén, Nehlig and Zvartau, 1999; Nehlig, 2005). It is at this point where someone who has consumed that much caffeine would be considered to be caffeine intoxicated, which can lead to hallucinations, mania, a very fast resting heart rate and abdominal pains (Fredholm, Bättig, Holmén, Nehlig and Zvartau, 1999). To reach the point of caffeine intoxication however varies from person to person, but it far exceeds the amount that any person would normally pursue to consume.
Prolonged caffeine consumption may lead to some adverse health effects, but also some positive outcomes (Nehlig, 2005; Smith, Gupta & Gupta, 2006). One of these adverse effects is the bodies sensitisation to adrenaline, which is the hormone that readies us for a 'fight or flight' situation. Which effects how we would mentally and physiologically react if we were in a real situation of danger or crisis, such that we may not act with the sense of urgency that is required, or we may engage in relatively more risk taking behaviour in these situations which may endanger ourselves or perhaps others (Nehlig, 2005; Smith, Gupta & Gupta, 2006). Other adverse consequences can include prolonged increased blood pressure, heart rate and many other physiological aspects which can be remedied by the reduction or cessation of the consumption of caffeine (Nehlig, 2005; Smith, Gupta & Gupta, (2006) Too much caffeine throughout the day can also lead to some sleep disturbances, such as an inability to fall asleep, obtain restful sleep and it can even induce insomnia (Nehlig, 2005; Smith, Gupta & Gupta, 2006). On the beneficial side however, it does maintain improved cognitive performance, mood and attention, even if an individual were to consume much more than they used to (Nehlig, 2005). The increased blood flow throughout the body can be useful if a person is engaging in strenuous physical activity such as sporting or going to the gym, it may result in improved stamina and performance which is why many athletes will consume caffeine before they perform (Nehlig, 2005; Smith, Gupta & Gupta, 2006).
How can this knowledge be applied?[edit | edit source]
If you have an existing motivation that you may be too fatigued to pursue, consider consuming some caffeine, as it may improve your mood and attention to such an extent that you will reach a productive state and follow through with your motivations. If you find that you are lacking motivation, consuming caffeine may not help you find it, but it may give you the energy you need to find it if you are fatigued. If you need to study for an exam or anything, try consuming some caffeine beforehand, as some evidence suggests that it enhances learning and memory through improved attention and mood (Nehlig, 2005; Smith, Gupta & Gupta, 2006). If you have a present motivation for exercise but feel as if you're too tired or you do not want to be too tired afterwards, try having some caffeine! The energy boost may be just what you need to push you ahead, and caffeine's cardiovascular effects improve physical stamina and performance by quite a bit. Try to avoid caffeine too close to your bed time though, probably up to 6 hours out or you may find that you will experience difficulties in sleeping and disturb your sleep cycle, and that will only lead to a bad following day (Nehlig, 2005)!
Conclusion[edit | edit source]
This chapter explained what caffeine is and how it interacts with the human body, both in psychological and in physiological aspects. Caffeine is a psycho-stimulatory drug that is found in plants such as coffee, tea, and cacao. It is similar in shape to the chemical found in the brain called adenosine, and is an antagonist to adenosine receptors. Accumulation of adenosine in the brain leads to the feeling of fatigue, as it slows down brain activity. Caffeine being an antagonist to adenosine receptors means that it competes with adenosine and binds with adenosine receptors, blocking the feeling of fatigue that is felt by adenosine. It also induces production of adrenaline, also known as the 'fight or flight' hormone which contributes to the alerting effects of caffeine. Dopamine reabsorption is also prevented in the frontal lobe when caffeine is present, this is how caffeine can improve mood as this leads to people feeling happy when they consume caffeine, and it is also the factor that can make caffeine somewhat addictive. Long term consumers of caffeine may notice that they require larger doses of caffeine in order for it to have the same effect. This is because our brain responds to not accumulating adenosine like it normally would by growing more adenosine receptors. This allows adenosine to continue to bind to these receptors unless there is more caffeine in the system to counteract this effect. Caffeine has a half life of about 6 hours, which means after an initial dose, after 6 hours have passed, only half of the caffeine that was present in the initial dose is still present, and it halves every 6 hours. This is probably the reason why many people would consider consuming multiple coffees (or teas, or energy drinks) throughout the day. The motivational effects that caffeine has do not directly influence it; rather it can enhance motivation as a secondary action, as caffeine improves individual mood and attention span. The improved mood and attention span is a much more fertile state for motivation to thrive, so an existing motivation will probably need to be present in order for it to work this way. This improved mood and attention span also enhances learning and memory, as some studies have shown that consuming caffeine before a study period allowed the students who consumed caffeine to retain more information. Since caffeine is a drug, it does have addictive properties. Motivations could arise in a regular coffee drinker that may not come about in anyone else who does not have a caffeine habit, including desperately seeking out a coffee when they have missed their daily dose, as well as the desire for more. If someone is a regular consumer of caffeine and they decide to quit or they are unable to get their fix, caffeine does have slight withdrawal effects. Many caffeine consumers would report of a persistent, generalised headache if they missed their dose, followed by a heightened sense of anxiety, and even more fatigued than they have ever been, even before they consumed caffeine. If someone were determined to rid themselves of caffeine and they suffered these withdrawal symptoms, the symptoms would eventually dissipate in a few weeks and they would eventually return to normal. While there is a lethal dose of caffeine to humans, it is physically impossible to ingest such an amount. The lethal dose is 150mg per kilogram a person weighs, meaning someone who weights 60 kilograms would have to consume 9,000 mg of caffeine in one go in order to suffer from any fatal effect. There is roughly 150mg in a standard cup of coffee, to put this into perspective. Before getting at all close to this point, someone consuming that much caffeine would succumb to caffeine intoxication, with the primary symptoms of sensory hallucinations and mania. Long term consumption of caffeine can lead to a few adverse health effects, such as a sensitisation to adrenaline, which can result in a loss of the sense of urgency required for emergency situations and may lead to riskier behaviours when in an emergency situation. The release of adrenaline also improves cardiovascular aspects and can be a useful contribution to an athlete's performance, or anyone who has the desire to exercise. The dosages of caffeine may need to become higher with frequent long term use, however its cognitive performance improving properties do not seem to diminish; it only takes more caffeine to produce the same effect. Some useful tips are detailed to give readers some advice on how caffeine consumption can enhance their lives, such as feeling too fatigued and have a lot to do? Have a coffee! Caffeine's stimulating effects, the release of adrenaline and its adenosine antagonist actions will make you feel alert and awake. Need to study for an important exam? Have a coffee! The improved memory and attention enhances learning greatly, you will be able to remember more! Want to engage in some physical exercise but feel as if you are too tired? Try having a coffee, that kick of adrenaline that gets your blood pumping will get you moving. Be careful though, avoid having caffeine too close to your bedtime, or you may have some trouble falling asleep and disrupt your sleeping pattern.
Quiz[edit | edit source]
Try this quick quiz and test what you have learnt by reading this chapter!
See also[edit | edit source]
For more information of how dopamine effects motivation see: Dopamine and Emotion
References[edit | edit source]
Boulenger, J., Patel, J., Post, R. M., Parma, A. M., Marangos, P. J. (1983). Chronic caffeine consumption increases the number os brain adenosine receptors. Life Sciences, 32(10). 1135-1142. DOI: 10.1016/0024-3205(83)90119-4
Dawkins, L., Shahzad, F., Ahmed, S. S., & Edmonds, C. J. (2011). Expectation of having consumed caffeine can improve performance and mood. Appetite, 57(3). 597-600. DOI: 10.1016/j.appet.2011.07.011
Fredholm, B. B. (1982). Adenosine actions and adenosine receptors after 1 week treatment with caffeine. Acta Physiologica Scandinavica, 115(2). 283-286. DOI: 10.1111/j.1748-1716.1982.tb07078.x
Fredholm, B. B. (1995). Adenosine, Adenosine Receptors and the Actions of Caffeine. Pharmacology & Toxicology, 76(2). 93-101. DOI: 10.1111/j.1600-0773.1995.tb00111.x
Fredholm, B. B., Bättig, K., Holmén, J., Nehlig, A., & Zvartau, E. E. Z. (1999). Actions of Caffeine in the Brain with Special Reference to Factors That Contribute to Its Widespread Use. Pharmacological Reviews, 51(1). 83-133.
Graham, K. (1988). Reasons for consumption and heavy caffeine use: Generalization of a model based on alcohol research. Addictive Behaviors, 13(2). 209-214. DOI: 10.1016/0304603(88)90015-9
Maridakis, V., Herring, M. P., & O'Conner, P. J. (2009). Sensitivity to Change in Cognitive Performance and Mood Measures of Energy and Fatigue in Response to Differing Doses of Caffeine or Breakfast. International Journal of Neuroscience, 119(7). 975-994. DOI: 10.1080/00207450802333995
Nehlig, A. (Eds.). (2005). Coffee, Tea, Chocolate, and the Brain. Boca Raton, Florida: CRC Press.
Nehlig, A. (1999). Are we dependent upon coffee and caffeine? A review on human and animal data. Neuroscience & Biobehavioural Reviews, 2(4). 563-576. DOI: 10.1016/S0149-7634(98)00050-5
Nehlig, A., Daval, J., & Debry, G. (1992). Caffeine and the central nervous system: mechanisms of action, biochemical, metabolic and psychostimulant effects. Brain Research Reviews, 17(2). 139-170. DOI: 10.1016/0165-0173(92)90012-B
Smith, B. D., Gupta, U., & Gupta, B. S. (Eds.). (2006) Caffeine and Activation Theory: Effects on Health and Behavior. Boca Raton, Florida: CRC Press.
Smith, R. (1987). CAFFEINE WITHDRAWAL HEADACHE. Journal of Clinical Pharmacy and Therapeutics, 12(1). 53-57. DOI: 10.111/j.1365-2710.1976.tb00419.x
External Links[edit | edit source]
- http://www.youtube.com/watch?v=4YOwEqGykDM - ASAP Science "Your Brain on Coffee"