Stimulation is a curious creature; it is a very important aspect of our daily lives yet it appears that in its unadulterated form it is notoriously unreliable. Without stimulation we become bored and unmotivated but with it we can achieve incredible feats. In its purest form, stimulation is the notion that something grabs our interest and ramps up our cognitive processes but for this to reliably happen we need to constantly come into contact with things that stimulate us and sadly this is rarely the case. We are constantly faced by mundane tasks in our daily lives that don’t stimulate us: studying things you are not interested in, washing the dishes, working a boring and repetitive job etc., but mundane is not synonymous with unimportant. Often times these mundane tasks are some of the most important tasks in our daily life so it is not surprising that most cultures on earth use substances that induce a sense of stimulation. The most common substance that is used for this purpose is caffeine, which is present in a variety of plants species. Caffeine can produce a stimulant effect at around 50 mg, which is about how much caffeine is in a cup of black tea. Coffee on the other hand has a much higher concentration of caffeine at about 100-200 mg per cup depending on the brewing method. In addition to this, coffee contains beta-carbolines, which bolster caffeine’s stimulant effect and thus it is unsurprising that it is one of the worlds most commonly consumed stimulants. Other traditionally used stimulants include; nicotine found in tobacco, cathinone found in khat, ephedrine found in Ephedra and arecoline found in the betel nut. More recently very strong stimulants that are based on the structures of traditionally used stimulants have been developed, such as various substituted phenethylamines and appear to be very popular amongst Ivy League students. It was recently reported that 1 in 5 Ivy League students are using illicit prescription stimulants such as amphetamines as learning aids. It is even rumored that the use of illicit prescription stimulants is not limited to just students, as professors seem to dip their toes into the world of prescription stimulants too. It is not surprising that this is happening, because as the famous mathematician Paul Erdős showed us, these perception stimulants are incredibly effective at ramping up our cognitive abilities even during the most mundane of tasks, and with the bar being set almost unrealistically high, the push for using them is becoming more and more widespread. However, the majority of stimulants, especially the stronger stimulants only have a very short window in which they are maximally effective. The rest of this article will focus on the use of sustainable stimulants and how we can achieve states of cognitive stimulation without the use of exogenous stimulants.
Our first order of business is to understand the difference between wakefulness and stimulation because this is often where many mistakes are made. When we are tired our cognitive functions are lowered across the board, we function even worse on mundane tasks and our performance also starts to decline on interesting tasks, but stimulants can bring us back to or above our normal baseline. Due to this, most stimulants are actually used to compensate for a lack of sleep, which means that we can be less successful at using stimulants sustainably for mundane or cognitively demanding tasks. Thus it is important that the first variable we are looking at improving is our sleep so that we can take a lack of wakefulness out of the question.
To gain some more insight on sleep and wakefulness we are going to take a look at caffeine, which has a fairly unique mechanism of action, compared to other stimulants.
The above diagram illustrates three important neurotransmitters involved in sleep and wakefulness. The first being adenosine, which activates the adenosine A1, A2A, A2B, and A3 receptors. Activation of these receptors, in particular the A1 receptor, causes the inhibition of the orexin receptors OX1, OX2 and the histamine H1 receptor which are very important regulators of wakefulness. When the orexin and histamine receptors are inhibited we become sleepy but when they are disinhibited we experience wakefulness. Thus when the adenosine receptor is being activated by adenosine, which builds up during the day and peaks at night, we become sleepy. During the course of our sleep, amongst many other processes we eliminate the adenosine that has built up during the day. This disinhibits orexin and histamine receptors, which allows us to experience wakefulness and optimum baseline cognition during the day. Caffeine however somewhat forgoes the need for sleep by blocking the adenosine receptor, which allows orexin and histamine receptors to become disinhibited despite elevated adenosine levels, this decreases levels of fatigue and brings us back to our baseline cognition. However, we want to surpass our baseline cognition and this is possible with caffeine but becomes fairly hard from a fatigue state.
Sometimes it is hard to get enough sleep but by practicing good sleep hygiene, regular bedtimes, utilizing fitness trackers or online sleep timers to track sleep stages and supplementing with a sleep enhancer such as L-tryptophan can greatly increase both the quantity and quality of our sleep. This will allow us to be at optimum cognitive performance during the day when we combine good sleep with smart stimulant use.
G Protein-Coupled Receptor Heterodimer Network
Back to adenosine! There are two types of neurotransmitter receptors in our brain, ionotropic and metabotropic, which are also known as G protein coupled-receptors. It is fairly common for these G protein coupled receptors to associate with other receptors around them. This process is called dimerization and usually occurs between different receptors within the same neurotransmitter class. Adenosine however, can dimerize with a variety of different neurotransmitter classes, a process that is called heterodimerization. These heterodimers can then form networks that all rely on adenosinergic neurotransmission. Thus blocking the adenosine receptors with caffeine can cause an enormous cascade of neurotransmission throughout the brain, which primes our senses and enhances our cognition above what is normally achievable. Add in the beta-carbolines found in coffee which enhance this neurotransmission cascade and we are presented with a strong sense of stimulation. However for some people this can manifest itself as a jittery feeling which can be very distracting. To combat this we can utilize a trick that green tea drinkers have been utilizing for a long time, add in a bit of the mildly relaxing amino acid L-theanine which is naturally present in shade grow green teas such as matcha. This causes a calm sense of stimulation by taking off caffeine’s edge and appears to enhance caffeine’s cognition enhancing effects.
So now that we have a solid understanding of stimulation, wakefulness and stimulants how do we build a smart stimulation regimen? As discussed earlier, stop relying on stimulants to counteract the effects of sleep deprivation and instead ensure quality sleep. Then use a stimulant such as caffeine on occasion rather than everyday. For example, don’t take a stimulant so that you can clean the dishes but rather save that stimulant for when you have to fill out important paperwork, complete a difficult work assignment or study for that one really boring but important class. By doing this we can keep tolerance low and ensure the long-term efficacy of our stimulant use. Now on to the actual stimulant, the caffeine levels in coffee fluctuate wildly but its beta-carboline content goes great with caffeine, thus opt for a caffeine free coffee and add in a accurately measured quantity of caffeine to it. This will ensure consistent effects from cup to cup. A convenient way to add in an accurately measured quantity of caffeine is to take a caffeine tablet alongside your caffeine free coffee and if you tend to become jittery then you can opt to take an L-Theanine capsule alongside that too.