Nootropics, also known as ‘brain boosters’, or ‘cognitive enhancers’ are made up of a variety of artificial and natural compounds that help in enhancing the cognitive activities of the brain by regulating or altering the production of neurochemicals and neurotransmitters in the brain. It improves blood flow, stimulates neurogenesis (the process by which neurons are produced in the body by neural stem cells), enhances nerve growth rate, modifies synapses, and improves cell membrane fluidity. Thus, positive changes are created within your body, which helps you to function optimally; whatever be your current lifestyle and individual needs.
Since coffee drinking may lead to a worsening of calcium balance in humans, we studied the serial changes of serum calcium, PTH, 1,25-dihydroxyvitamin D (1,25(OH)2D) vitamin D and calcium balance in young and adult rats after daily administration of caffeine for 4 weeks. In the young rats, there was an increase in urinary calcium and endogenous fecal calcium excretion after four days of caffeine administration that persisted for the duration of the experiment. Serum calcium decreased on the fourth day of caffeine administration and then returned to control levels. In contrast, the serum PTH and 1,25(OH)2D remained unchanged initially, but increased after 2 weeks of caffeine administration…In the adult rat group, an increase in the urinary calcium and endogenous fecal calcium excretion and serum levels of PTH was found after caffeine administration. However, the serum 1,25(OH)2D levels and intestinal absorption coefficient of calcium remained the same as in the adult control group.
Many people prefer the privacy and convenience of ordering brain boosting supplements online and having them delivered right to the front door. At Smart Pill Guide, we have made the process easier, so you can place your order directly through our website with your major credit card or PayPal. Our website is secure, so your personal information is protected and all orders are completely confidential.

If this is the case, this suggests some thoughtfulness about my use of nicotine: there are times when use of nicotine will not be helpful, but times where it will be helpful. I don’t know what makes the difference, but I can guess it relates to over-stimulation: on some nights during the experiment, I had difficult concentrating on n-backing because it was boring and I was thinking about the other things I was interested in or working on - in retrospect, I wonder if those instances were nicotine nights.

Piracetam (known also by the name Nootropil) is one of the best known Nootropics and makes up part of the Racetam family along with Aniracetam, Phenylpiracetam, Pramiracetam, Oxiracetam, Nefiracetam, Coluracetam and Nebracetam. These are all synthetic compounds that have been created in the lab, but there are also a number of effective herbal and natural nootropic supplements.
Including comprehensive lists of what to eat and what to avoid, a detailed quiz that will tell you where you are on the brain health spectrum, and 24 mouth-watering brain-boosting recipes that grow out of Dr. Mosconi's own childhood in Italy, Brain Food gives us the ultimate plan for a healthy brain. Brain Food will appeal to anyone looking to improve memory, prevent cognitive decline, eliminate brain fog, lift depression, or just sharpen their edge.
At this point, I discovered I had run out of magnesium pills and had forgotten to order the magnesium citrate powder I’d intended to. I still had a lot of Noopept pills for the concurrently running second Noopept self-experiment, but since I wanted to wrap up some other experiments with a big analysis at the end of the year, I decided to halt and resume in January 2014.
"Over the years, I have learned so much from the work of Dr. Mosconi, whose accomplished credentials spanning both neuroscience and nutrition are wholly unique. This book represents the first time her studies on the interaction between food and long-term cognitive function reach a general audience. Dr. Mosconi always makes the point that we would eat differently and treat our brains better if only we could see what we are doing to them. From the lab to the kitchen, this is extremely valuable and urgent advice, complete with recommendations that any one of us can take."
However, they fell short in several categories. The key issue with their product is that it does not contain DHA Omega 3 and the other essential vitamins and nutrients needed to support the absorption of Huperzine A and Phosphatidylserine. Without having DHA Omega 3 it will not have an essential piece to maximum effectiveness. This means that you would need to take a separate pill of DHA Omega 3 and several other essential vitamins to ensure you are able to reach optimal memory support. They also are still far less effective than our #1 pick’s complete array of the 3 essential brain supporting ingredients and over 30 supporting nutrients, making their product less effective.
Wild salmon. Deep-water fish, such as salmon, are rich in omega-3 essential fatty acids, which are essential for brain function, says Kulze. Both she and Pratt recommend wild salmon for its "cleanliness" and the fact that it is in plentiful supply. Omega-3s also contain anti-inflammatory substances. Other oily fish that provide the benefits of omega-3s are sardines and herring, says Kulze; she recommends a 4-ounce serving, two to three times a week.
I have personally found that with respect to the NOOTROPIC effect(s) of all the RACETAMS, whilst I have experienced improvements in concentration and working capacity / productivity, I have never experienced a noticeable ongoing improvement in memory. COLURACETAM is the only RACETAM that I have taken wherein I noticed an improvement in MEMORY, both with regards to SHORT-TERM and MEDIUM-TERM MEMORY. To put matters into perspective, the memory improvement has been mild, yet still significant; whereas I have experienced no such improvement at all with the other RACETAMS.

Looking at the prices, the overwhelming expense is for modafinil. It’s a powerful stimulant - possibly the single most effective ingredient in the list - but dang expensive. Worse, there’s anecdotal evidence that one can develop tolerance to modafinil, so we might be wasting a great deal of money on it. (And for me, modafinil isn’t even very useful in the daytime: I can’t even notice it.) If we drop it, the cost drops by a full $800 from $1761 to $961 (almost halving) and to $0.96 per day. A remarkable difference, and if one were genetically insensitive to modafinil, one would definitely want to remove it.
Since LLLT was so cheap, seemed safe, was interesting, just trying it would involve minimal effort, and it would be a favor to lostfalco, I decided to try it. I purchased off eBay a $13 48 LED illuminator light IR Infrared Night Vision+Power Supply For CCTV. Auto Power-On Sensor, only turn-on when the surrounding is dark. IR LED wavelength: 850nm. Powered by DC 12V 500mA adaptor. It arrived in 4 days, on 7 September 2013. It fits handily in my palm. My cellphone camera verified it worked and emitted infrared - important because there’s no visible light at all (except in complete darkness I can make out a faint red light), no noise, no apparent heat (it took about 30 minutes before the lens or body warmed up noticeably when I left it on a table). This was good since I worried that there would be heat or noise which made blinding impossible; all I had to do was figure out how to randomly turn the power on and I could run blinded self-experiments with it.
For obvious reasons, it’s difficult for researchers to know just how common the “smart drug” or “neuro-enhancing” lifestyle is. However, a few recent studies suggest cognition hacking is appealing to a growing number of people. A survey conducted in 2016 found that 15% of University of Oxford students were popping pills to stay competitive, a rate that mirrored findings from other national surveys of UK university students. In the US, a 2014 study found that 18% of sophomores, juniors, and seniors at Ivy League colleges had knowingly used a stimulant at least once during their academic career, and among those who had ever used uppers, 24% said they had popped a little helper on eight or more occasions. Anecdotal evidence suggests that pharmacological enhancement is also on the rise within the workplace, where modafinil, which treats sleep disorders, has become particularly popular.
Much better than I had expected. One of the best superhero movies so far, better than Thor or Watchmen (and especially better than the Iron Man movies). I especially appreciated how it didn’t launch right into the usual hackneyed creation of the hero plot-line but made Captain America cool his heels performing & selling war bonds for 10 or 20 minutes. The ending left me a little nonplussed, although I sort of knew it was envisioned as a franchise and I would have to admit that showing Captain America wondering at Times Square is much better an ending than something as cliche as a close-up of his suddenly-opened eyes and then a fade out. (The movie continued the lamentable trend in superhero movies of having a strong female love interest… who only gets the hots for the hero after they get muscles or powers. It was particularly bad in CA because she knows him and his heart of gold beforehand! What is the point of a feminist character who is immediately forced to do that?)↩
One should note the serious caveats here: it is a small in vitro study of a single category of human cells with an effect size that is not clear on a protein which feeds into who-knows-what pathways. It is not a result in a whole organism on any clinically meaningful endpoint, even if we take it at face-value (many results never replicate). A look at followup work citing Rapuri et al 2007 is not encouraging: Google Scholar lists no human studies of any kind, much less high-quality studies like RCTs; just some rat followups on the calcium effect. This is not to say Rapuri et al 2007 is a bad study, just that it doesn’t bear the weight people are putting on it: if you enjoy caffeine, this is close to zero evidence that you should reduce or drop caffeine consumption; if you’re taking too much caffeine, you already have plenty of reasons to reduce; if you’re drinking lots of coffee, you already have plenty of reasons to switch to tea; etc.
Theanine can also be combined with caffeine as both of them work in synergy to increase memory, reaction time, mental endurance, and memory. The best part about Theanine is that it free of side effects and is easily available in the form of capsules.  A natural option would be to use a good green tea brand which constitutes of tea grown in the shade, because then Theanine would be abundantly present in it.

Seriously. Every single thing you experience comes through your brain. It create the fabric of your reality, and by the same token, the energy your brain makes is what allows you to shape that reality. Work, relationships, success, happiness — everything depends on your brain, and building a stronger one will trigger upgrades that extend across every aspect of your life.
Between midnight and 1:36 AM, I do four rounds of n-back: 50/39/30/55%. I then take 1/4th of the pill and have some tea. At roughly 1:30 AM, AngryParsley linked a SF anthology/novel, Fine Structure, which sucked me in for the next 3-4 hours until I finally finished the whole thing. At 5:20 AM, circumstances forced me to go to bed, still having only taken 1/4th of the pill and that determines this particular experiment of sleep; I quickly do some n-back: 29/20/20/54/42. I fall asleep in 13 minutes and sleep for 2:48, for a ZQ of 28 (a full night being ~100). I did not notice anything from that possible modafinil+caffeine interaction. Subjectively upon awakening: I don’t feel great, but I don’t feel like 2-3 hours of sleep either. N-back at 10 AM after breakfast: 25/54/44/38/33. These are not very impressive, but seem normal despite taking the last armodafinil ~9 hours ago; perhaps the 3 hours were enough. Later that day, at 11:30 PM (just before bed): 26/56/47.
This tendency is exacerbated by general inefficiencies in the nootropics market - they are manufactured for vastly less than they sell for, although the margins aren’t as high as they are in other supplement markets, and not nearly as comical as illegal recreational drugs. (Global Price Fixing: Our Customers are the Enemy (Connor 2001) briefly covers the vitamin cartel that operated for most of the 20th century, forcing food-grade vitamins prices up to well over 100x the manufacturing cost.) For example, the notorious Timothy Ferriss (of The Four-hour Work Week) advises imitators to find a niche market with very high margins which they can insert themselves into as middlemen and reap the profits; one of his first businesses specialized in… nootropics & bodybuilding. Or, when Smart Powders - usually one of the cheapest suppliers - was dumping its piracetam in a fire sale of half-off after the FDA warning, its owner mentioned on forums that the piracetam was still profitable (and that he didn’t really care because selling to bodybuilders was so lucrative); this was because while SP was selling 2kg of piracetam for ~$90, Chinese suppliers were offering piracetam on AliBaba for $30 a kilogram or a third of that in bulk. (Of course, you need to order in quantities like 30kg - this is more or less the only problem the middlemen retailers solve.) It goes without saying that premixed pills or products are even more expensive than the powders.
One SCFA in particular, called propionic acid, has been identified as a driver for abnormal behaviour that is related to both ADHD and the autism spectrum. This SCFA can alter metabolic and immune pathways, as well as gene expression, which can affect the functionality of the brain cells and their receptivity to neurotransmitters, as well as their ability to regenerate and regulate inflammatory responses. Certain strains of pathogenic bacteria, such as clostridia, have been implicated in producing large amounts of propionic acid. This strain of bacteria is naturally present in the gut, however, an overgrowth can occur when good bacteria levels are compromised and/or there is an acute infection. In addition, processed wheat and dairy products often contain propionic acid as a food preservative in the form of calcium propionate.
Nootrobox co-founder Geoffrey Woo declines a caffeinated drink in favour of a capsule of his newest product when I meet him in a San Francisco coffee shop. The entire industry has a “wild west” aura about it, he tells me, and Nootrobox wants to fix it by pushing for “smarter regulation” so safe and effective drugs that are currently unclassified can be brought into the fold. Predictably, both companies stress the higher goal of pushing forward human cognition. “I am trying to make a smarter, better populace to solve all the problems we have created,” says Nootroo founder Eric Matzner.

One of the most obscure -racetams around, coluracetam (Smarter Nootropics, Ceretropic, Isochroma) acts in a different way from piracetam - piracetam apparently attacks the breakdown of acetylcholine while coluracetam instead increases how much choline can be turned into useful acetylcholine. This apparently is a unique mechanism. A crazy Longecity user, ScienceGuy ponied up $16,000 (!) for a custom synthesis of 500g; he was experimenting with 10-80mg sublingual doses (the ranges in the original anti-depressive trials) and reported a laundry list of effects (as does Isochroma): primarily that it was anxiolytic and increased work stamina. Unfortunately for my stack, he claims it combines poorly with piracetam. He offered free 2g samples for regulars to test his claims. I asked & received some.
But when aficionados talk about nootropics, they usually refer to substances that have supposedly few side effects and low toxicity. Most often they mean piracetam, which Giurgea first synthesized in 1964 and which is approved for therapeutic use in dozens of countries for use in adults and the elderly. Not so in the United States, however, where officially it can be sold only for research purposes.
[…] The 7 Best Brain Boosting Supplements | Live in the Now … – Natural Health Recipes » Top 12 supplements for brain on October 18, 2012 at 7:37 AM … Gingko Biloba, Phosphatidyl Serine and Coenzyme Q10. Opt for the best brain supplements and stay fit with an active brain. You should be very careful while choosing the right supplement […] Reply. […]

Because modafinil works in a manner similar to methylphenidate, it also bears similar risks. The improper dosage or abuse of modafinil may lead to the disrupted development of executive controls like decision-making and working memory. Modafinil’s effects may also depend upon the IQ of the taker. Two university studies determined that in a test of sustained attention, modafinil only improved cognition in the group with “lower” IQs. Although safer than other stimulants due to its milder effect on neurotransmitter levels, there are still risks associated with any kind of drug that affects dopaminergic neurotransmission, mostly because this can lead to addiction and, similar to a pornography user who needs increasingly fringe porn to achieve the same effect, can produce a resistance or lowered sensitivity to dopamine.
With just 16 predictions, I can’t simply bin the predictions and say yep, that looks good. Instead, we can treat each prediction as equivalent to a bet and see what my winnings (or losses) were; the standard such proper scoring rule is the logarithmic rule which pretty simple: you earn the logarithm of the probability if you were right, and the logarithm of the negation if you were wrong; he who racks up the fewest negative points wins. We feed in a list and get back a number:
Its high levels of collagen help reduce intestinal inflammation, and healing amino acids like proline and glycine keep your immune system functioning properly and help improve memory. Bone broth is what I prescribe most frequently to my patients because it truly helps heal your body from the inside out. You’ll also be surprised at how simple and economical it is to make at home with my Beef Bone Broth Recipe.
A large review published in 2011 found that the drug aids with the type of memory that allows us to explicitly remember past events (called long-term conscious memory), as opposed to the type that helps us remember how to do things like riding a bicycle without thinking about it (known as procedural or implicit memory.) The evidence is mixed on its effect on other types of executive function, such as planning or ability on fluency tests, which measure a person’s ability to generate sets of data—for example, words that begin with the same letter. 

Caffeine, Tulsi and Astragalus: Tulsi is one of the greatest calming adaptogens that exists, trusted and revered for centuries in Ayurvedic medicine and culture. Tulsi has been researched and shown to uplift mood, support digestion, and promote balanced energy. Because it’s also an anxiolytic (causes anti-anxiety effects) tulsi, similar to coffee with L-theanine, does a good job balancing out any over-stimulating effects of the caffeine in coffee. But you can also take things one step further and blend in astragalus, which, in Chinese medicine, is considered a “strong” Ki invigorating herb that provides a stable source of non-crashing energy. Astragalus also contains an enormous variety of saponins, flavonoids, and polysaccharides, and is considered to be a “longevity adaptogen”. Pairing with antioxidant-rich coffee and tulsi produces a match made in longevity heaven. For this blend, which I often use if drinking coffee in the afternoon, I’m a fan of the Four Sigmatic Adaptogen Blend, which contains coffee, astragalus, tulsi and cinnamon.
The nootropics I’m taking are called RISE, and they're made by a company called Nootrobox, which was started by Geoffrey Woo, a young Stanford computer science graduate. There's no one common ingredient in nootropics; what unites them is the intent to improve brain performance. The RISE stack, which costs $29 plus shipping for 30 pills, contains 350 mg of bacopa monnieri powder (an herb that is commonly used medicinally in South Asia), 100 mg of L-theanine (an amino acid found in green tea), and 50 mg of caffeine (about the amount in a can of Diet Coke). Like most nootropics, the RISE stack itself isn't FDA-approved for use as a cognitive enhancer, but Nootrobox says that the compounds within it are approved as dietary supplements. "We use the precise ingredients at the right dosages and the right ratios as supported by double-blind, peer-reviewed clinicals," Nootrobox's site claims.
So how do I pull off this stack? It’s quite simple, really. I order 1-milligram nicotine toothpicks on Amazon that I suck on when I’m downing a cup of coffee (the cinnamon flavor blends quite nicely with a cup o’ joe) and I also keep a dispenser of 1.5-milligram nicotine mints in my office. Warning: nicotine can be addictive. I recommend limiting yourself to no more than 1-2 toothpicks and 1-2 mints per day, and only using on more cognitively demanding days. As a bonus, both caffeine and nicotine are potent ergogenic, physical performance-enhancing aids (albeit in higher amounts, closer to 100+ milligrams for caffeine and 2.5+ milligrams for nicotine).
Whether you want to optimise your nutrition during exam season or simply want to stay sharp in your next work meeting, paying attention to your diet can really pay off. Although there is no single 'brain food' that can protect against age-related disorders such as Alzheimers' or dementia, and there are many other medical conditions that can affect the brain, paying attention to what you eat gives you the best chance of getting all the nutrients you need for cognitive health.
Farah told me: "These drugs will definitely help some technically normal people - that is, people who don't meet the diagnostic criteria for ADHD or any kind of cognitive impairment." But, she emphasised, "They will help people in the lower end of the ability range more than in the higher end." One explanation for this phenomenon might be that the more adept you are at a given task, the less room you have to improve. Farah has a hunch that there may be another reason that existing drugs - so far, at least - don't offer as much help to people with greater intellectual abilities. Drugs like Ritalin and Adderall work in part by elevating the amount of dopamine in the brain. Dopamine is something you want just enough of: too little, and you may not be as alert and motivated as you need to be; too much, and you may feel overstimulated. Neuroscientists have discovered that some people have a gene that leads the brain to break down dopamine faster, leaving less of it available; such people are generally a little worse at certain cognitive tasks. People with more available dopamine are generally somewhat better at the same tasks. It makes sense, then, that people with naturally low dopamine would benefit more from an artificial boost.
REPUTATION: We were blown away by the top-notch reputation that Thrive Naturals has in the industry. From the consumers we interviewed, we found that this company has a legion of loyal brand advocates. Their customers frequently told us that they found Thrive Naturals easy to communicate with, and quick to process and deliver their orders. The company has an amazing track record of customer service and prides itself on its Risk Free No Questions Asked 1-Year Money Back Guarantee. As an online advocate for consumer rights, we were happy to see that they have no hidden fees nor ongoing monthly billing programs that many others try to trap consumers into.
Working memory has been likened to a mental scratch pad: you use it to keep relevant data in mind while you're completing a task. (Imagine a cross-examination, in which a lawyer has to keep track of the answers a witness has given and formulate new questions based on them.) In one common test subjects are shown a series of items - usually letters or numbers - and then presented with challenges: was this number or letter in the series? Was this one? In the working-memory tests, subjects performed better on neuroenhancers, though several of the studies suggested that the effect depended on how good a subject's working memory was to begin with: the better it was, the less benefit the drugs provided.
Besides Adderall, I also purchased on Silk Road 5x250mg pills of armodafinil. The price was extremely reasonable, 1.5btc or roughly $23 at that day’s exchange rate; I attribute the low price to the seller being new and needing feedback, and offering a discount to induce buyers to take a risk on him. (Buyers bear a large risk on Silk Road since sellers can easily physically anonymize themselves from their shipment, but a buyer can be found just by following the package.) Because of the longer active-time, I resolved to test the armodafinil not during the day, but with an all-nighter.
Some people aren’t satisfied with a single supplement—the most devoted self-improvers buy a variety of different compounds online and create their own custom regimens, which they call “stacks.” According to Kaleigh Rogers, writing in Vice last year, companies will now take their customers’ genetic data from 23andMe or another source and use it to recommend the right combinations of smart drugs to optimize each individual’s abilities. The problem with this practice is that there’s no evidence the practice works. (And remember, the FDA doesn’t regulate supplements.) Find out the 9 best foods to boost your brain health.
Choline is very important for cognitive function because it is a precursor to Acteylcholine. Your body needs enough choline to convert into Acteylcholine to keep your brain healthy. For this reason, choline supplements are often considered great nootropics, even by themselves. CDP-Choline and Alpha GPC are the best sources for supplemental Choline.
It’s that time of the year again. It’s Blue Monday. We’re halfway into January, trudging through the deepest and darkest of the winter months, as we try to keep our heads high after the Christmas festivities with the motivation of our New Year’s resolutions. Some of you may have never heard of Blue Monday and let’s just say you’re not exactly missing out.

At this point I began to get bored with it and the lack of apparent effects, so I began a pilot trial: I’d use the LED set for 10 minutes every few days before 2PM, record, and in a few months look for a correlation with my daily self-ratings of mood/productivity (for 2.5 years I’ve asked myself at the end of each day whether I did more, the usual, or less work done that day than average, so 2=below-average, 3=average, 4=above-average; it’s ad hoc, but in some factor analyses I’ve been playing with, it seems to load on a lot of other variables I’ve measured, so I think it’s meaningful).

Awesome list. You are what you eat both mentally and physically. Studies have shown that food therapy can alleviate depression, anxiety and stress, as well as reduce chances of developing Alzheimer’s later on in life. Here’s an additional list of brain food recipes that can improve your clarity of thinking.
One of the most popular legal stimulants in the world, nicotine is often conflated with the harmful effects of tobacco; considered on its own, it has performance & possibly health benefits. Nicotine is widely available at moderate prices as long-acting nicotine patches, gums, lozenges, and suspended in water for vaping. While intended for smoking cessation, there is no reason one cannot use a nicotine patch or nicotine gum for its stimulant effects.
Looking at the prices, the overwhelming expense is for modafinil. It’s a powerful stimulant - possibly the single most effective ingredient in the list - but dang expensive. Worse, there’s anecdotal evidence that one can develop tolerance to modafinil, so we might be wasting a great deal of money on it. (And for me, modafinil isn’t even very useful in the daytime: I can’t even notice it.) If we drop it, the cost drops by a full $800 from $1761 to $961 (almost halving) and to $0.96 per day. A remarkable difference, and if one were genetically insensitive to modafinil, one would definitely want to remove it.
Ginkgo Biloba Leaf(23% extract), Phosphatidylserine 4% Complex(consisting of Lecithin and Phosphatidylserine),N-Acetyl L-Carnitine HCI, St. John's Wort(0.3% extract)(fower heads),L-Glutamine,Dimethylaminoethanol Bitartrate, Bacopa monnieri Leaf Extract(20% bacosides), Vinpocetine(seeds), Huperzine-A(aerial Plant) ; other ingredients: Gelatin(bovine), vegetable magnesium stearate, microcrystalline cellulose and silicon dioxide
On the other hand, sometimes you’ll feel a great cognitive boost as soon as you take a pill. That can be a good thing or a bad thing. I find, for example, that modafinil makes you more of what you already are. That means if you are already kind of a dick and you take modafinil, you might act like a really big dick and regret it. It certainly happened to me! I like to think that I’ve done enough hacking of my brain that I’ve gotten over that programming… and that when I use nootropics they help me help people.
This research is in contrast to the other substances I like, such as piracetam or fish oil. I knew about withdrawal of course, but it was not so bad when I was drinking only tea. And the side-effects like jitteriness are worse on caffeine without tea; I chalk this up to the lack of theanine. (My later experiences with theanine seems to confirm this.) These negative effects mean that caffeine doesn’t satisfy the strictest definition of nootropic (having no negative effects), but is merely a cognitive enhancer (with both benefits & costs). One might wonder why I use caffeine anyway if I am so concerned with mental ability.
Amphetamine – systematic reviews and meta-analyses report that low-dose amphetamine improved cognitive functions (e.g., inhibitory control, episodic memory, working memory, and aspects of attention) in healthy people, and in individuals with ADHD.[21][22][23][25] A 2014 systematic review noted that low doses of amphetamine also improved memory consolidation, in turn leading to improved recall of information in non-ADHD youth.[23] It also improved task saliency (motivation to perform a task) and performance on tedious tasks that required a high degree of effort.[22][24][25]