3X3 Rubik's cube on top of desk
Photo by Alvaro Reyes on Unsplash

The following article is going to focus on hacks that have been clinically tested and reviewed by scientists. I typed in “Learning Hacks” inside Google and summarized top mentioned hacks. After excluding some vague methods, I then searched each keyword inside Google Scholar to see which hacks work, and which one is better.

Here’s a cheat sheet of 15 most commonly touted cognitive-boosting methods along with their respective evidence.

1. Sleep

Why brain hackers use it:

It is obvious. A better sleep, a better concentration. However, busy people are looking for short but quality sleep.

The evidence says:

A large number of studies undeniably suggest that sleep helps cognitive performance and memory consolidations. An extensive clinical review in 2006 found that both sleep quality and quantity are strongly related to student academic performance (regardless of education levels). And sleep loss often relates to the poor performance of declarative and procedural memories in students.

The paper also pointed out that findings from studies in which sleep was intentionally limited or optimized showed, respectively, a worsening and an improvement in cognitive ability and academic performance. Also, there are various studies to prove that sleep between studying helps consolidate and process the meaning of memories.

What you should know:

Sleep is the most well-rounded cognitive enhancer. Both the quality and quantity of sleep matters. Long sleep (>= 11 hours/d) in a large scale study has found to be significantly associated with mortality! An adult averagely needs 7.5-9 hours of sleep each day. Although there are formulas to calculate sleep hours, the best way to find it out is by testing yourself.

2. Caffeine

Why brain hackers use it:

Unlike its riskier peers like Amphetamine pills, coffee and tea are the most welcomed vehicle to deliver psychoactive substance. But there is also an ongoing worry on long-term consumption of caffeine. The needs of decaffeinated teas and coffees are on the rise.

The evidence says:

The caffeine is effective in improving cognition by blocking adenosine receptors. It helps us fight against fatigues due to sleep loss. A systematic review in 2016 summarized that low to moderate doses (40 – 300 mg) enhance cognition, and doses higher than 200 mg improve physical performance across a spectrum of sports.

You should know:

Caffeine helps both cognitive and physical performance, and it is not as unhealthy as many think. However, high doses (more than 300 mg) for children and pregnant women should be avoided. Also, a study on school-aged children shows that caffeine brings forward more anxiety on the participants, although the sample size was only 21. To help you have a better idea on dose control, I list out the table of estimated caffeine content in beverages, food, and dietary supplements below.

The estimated caffeine content of beverages, foods, and dietary supplements (Lieberman et al., 2010; McLellan and Lieberman, 2012).

3. Meditation

Why brain hackers use it:

Meditation gained its popularity since the 1960s. Fueled by Steve Jobs’ obsession of Buddhism, many meditation courses and apps have slowly evolved to mainstream hot buzz. Meditation practices are believed to improve attention span and increase intelligence significantly.

The evidence says:

Many papers published suggest that both brief and long-term mediation practices help enhance working memory capacity. However, a systematic meta-analysis found out that all of those studies are either poorly designed or executed in terms of sample sizes, study duration, and population. Never the less, there is strong evidence supporting mental health improvement by meditation, which indirectly related to cognition performance.

What you should know:

Meditation may contribute to work passivity and greater self-centrality. Also, different types of meditations seem to have different negative effects on the human body. Transcendental Meditation, for example, is found in several studies to posit negative effects on cognitive functions.

4. Note-taking by hand

Why brain hackers use it:

Note-taking by hand never seems to lose its charisma even with the popularity of various note apps. Learners often find from their experience that after writing the things down, they have a better memory of the knowledge. We talk about multiple benefits from practitioners across the industry in our previous post, Demystifying the War Between Longhand and Digital Mind Maps.

The evidence says:

In research published in 2014, researchers found students who took note longhand performed better in conceptual questions and memory retention. According to the cognitive scientists behind the paper, it is the chunking and paraphrasing in a limited time that helps students process the information intensively.

What you should know:

Apart from longhand note-taking, any other activities that involve paraphrasing in a limited time help you digest the knowledge. For example, cheatsheet in one page, drawing diagrams, and self-testing all work under the same mechanism. But be aware that reading someone else’ note or taking the note by laptop would not help, because they do not force you to chunk the information.

5. Spaced Repetition System (SRS)

Why brain hackers use it:

Based on the famous Forgetting Curve, SRS provides a repeated schedule for learners to review at the best moment and retain the new information for as long as possible. The system emerged as early as a century ago and is playing a critical role in educational software.

The evidence says:

Hundreds if not thousands of studies have confirmed SRS does help retention of memory. The recent studies are turning to research on conceptual learning like STEM, as previous studies are more on memorizing than understanding. A review article in 2016 summarizes that SRS not only helps students in “memory retention but also in problem-solving and generalization to a new situation.”

What you should know:

Although there are some articles on finding the perfect schedule for SRS, what matters more is you actually spacing the review over time. Absolute spacing is the key.

6. Mind map

Why brain hackers use it:

Based on the theory of learning styles, some hackers categorize themselves as visual thinkers. As mind map is an easy-to-master visual note-taking skill, it is widely accepted across the globe.

The evidence says:

Although there are thousands of studies on mind maps, most of them are criticized by poorly designed experiments in terms of sample sizes. The working mechanism of a mind map is to create a mental association between concepts. In a 2010 study, researchers found that students who created mind maps in classes remembered more ideas and understood better in connections between ideas.

What you should know:

It works similar like longhand note-taking, you should use your hand to chunk and organize the information. The software might help after you have already de-cluster your mind.

7. Background music

Why brain hackers use it:

Music seems to have a magic effect on people’s performance. Some productivity hackers claim certain kind of music help them focus and think faster.

The evidence says:

The effects of music are mostly unclear across the population. Most of the studies conducted are suffered from the problem of low sample sizes and narrowed generalization. However, the majority of the researches point out insignificant if not adverse effects of music to participants.

What you should know:

Music and noise seem to have stronger adverse effects on introverts, as shown in studies published in 2011 and 2013. But calming music can indirectly improve cognition by arousal and better mood.

8. Interleaving

Why brain hackers use it:

Switching between different tasks and subjects is promoted as secret weapons of straight-A students.

The evidence says:

A study of 2013 found that switching between short tasks does have optimal benefits on returns. However, it also increases the risks of making mistakes. A larger-scale study in 2014 used computational models to look into multitasking impacts across task types and individuals and found that the return is not always optimal. The strategies of switching and choosing tasks strongly influenced the result.

What you should know:

Multitasking is more known to have negative impacts on cognition performance. The best strategies are to mixing information across different topics, but not tasks involving different motors. A study in 2012 also stressed the importance of choosing a proper chunk time.

9. Deliberate practice

Why brain hackers use it:

Honed by thousands of famous productivity hackers, deliberate practice has become a commonly known tactic to master professional skills.

The evidence says:

An article in 2006 summarized the major discovers from the past research on deliberate practices. It stated that deliberate practices significantly improved pianists’ expert performance, and the method served as a good indicator of academic achievements across high school and undergraduate students.

What you should know:

In the same article, the author also stressed that deliberate practices might only work for more established domains. The formation of the practice framework relies on structures and organization of the subject. If it is a newly emerged knowledge, deliberate practices are hard to apply.

10. Exercise

Why brain hackers use it:

Fight against drowsiness, calm down the nerve, improve attention span, and much more. Exercises are always go-to advice from many gurus and bloggers.

The evidence says:

There are ample amount of studies on the relationship between exercises and cognition capacity. Although the majority are not directly on healthy adults, some studies do imply that exercises have life-long chronic effects on brain health. It is shown very clearly that the number of neuron cells continues to increase after workouts. In a review article of 2018, physical exercises are summarized as an enhancer across all aspects of cognitive functions including, speed, attention, execution, verbal learning, and memory.

What you should know:

Currently, there are no clinical studies on longitudinal effects on human adults. Exercises are definitely not one cure for all. Aerobic exercises are found to have better support on cognitive functions than other types. But only inadequate amount (around 30 min per day), as aerobic athletes also found to be suffered from fatigue and signs of depression, which might adversely impact cognition.

11. Read-out-loud/Teaching

Why brain hackers use it:

Practically and even academically, they are techniques involving thinking and reading from you, yourself. This technique is promoted across different study bloggers, as those bloggers found positive returns on the efficiency of cramming knowledge. 

The evidence says:

Read-out-loud and teaching are under the term, destination memory, the memory of things you have told someone. There are only a few articles studying this technique. In one study of 2007, aloud presentation is found to slower the mesmerizing rate but lengthen the retention span. In a study that compares source memory (memory of things you have heard) and destination memory, researchers found that destination memory is highly related to source memory. Also, participants remembered better if they are teaching someone.

What you should know:

More recent studies in 2017 and 2018 further pointed out that hearing oneself has unique effects on memory. Perhaps that explains the correlation between source and destination memory. And you should make sure you can listen to yourself clearly in this process.

12. Game

Why brain hackers use it:

Comparing to its initial lousy reputation, game lovers and supporters are starting to changing mainstream views on games. Productivity hackers demonstrate their positive feedbacks on trying serious games to learn.

The evidence says:

A study in 2015 experimented game-based learning on adolescent learners, it found that the more challenging a game is, the better the engagement and learning outcomes. But the latest study on the relationship between metacognition and video games proposed only a weak connection. A large-scale, high-quality clinical review summarized that no studies demonstrate a precise mechanism between games and working memory. Worse-still, games might negatively affect the intrinsic motivation of learning in the long-term.

What you should know:

Mindful of game addiction. There is far more evidence on side-effects of game addictions. Game addictions are connected with higher anxiety and stress and lower mental performance. And you should better focus more on serious games than entertainments.

13. Test

Why brain hackers use it:

Testing oneself is widely touted by study bloggers. And many education apps have applied this technique. Brain hackers believe that it can help improve memories.

The evidence says:

A clinical study in 2017 conducted experiments on both children and adults. The research team found that although memory accuracy varied across age groups, all of the participants’ recollection accuracy was improved by the test practices. Analogical reasoning ability is also found to be benefited from recalling practices.

What you should know:

Testing is one of the most promising study hacks listed here. Even test without feedbacks is found to impact metacognition positively.

14. Nicotine

Why brain hackers use it:

Despite its side-effects, there is an increasing number of high achievers taking nicotine products. The practice not only improves concentration but also help consolidate knowledge.

The evidence says:

A 2018 study conducted tests on nicotine effects on late-life depression patients, it stated that nicotine has the potential to improve elders’ cognitive functions and mood. Nicotine also enhances our mood by stimulating our dopamine system.

What you should know:

The effects on mind acuity is also a liability of nicotine addictions. Chronically to middle-age people, nicotine adversely affects their mental performance. Pregnant women should avoid nicotine at any doses.

15. Brain-boosted diets

Why brain hackers use it:

Using food and other natural supplements to boost cognition is always a hot buzz. After all, it doesn’t feel like any threats to the body.

The evidence says:

The majority of studies on prevalent dietary factors, say, omega-3 fatty acid, is criticized for their small sample sizes and weak effects on cognition. But a survey on high fat and sugar diet showed that it impaired spatial learning and memory.

What you should know:

A healthy diet would never harm you, although you might not be able to improve cognition by eating. You also do not need to obsessed with certain substances, as they are usually over-marketed.

Summary

Among all the hacks listed above, the best mental enhancers are good sleep, proper exercises and testing. Pretty cliche yet helpful. Not to mention reciprocal effects between rest and workouts

Longhand note-taking, mind map, and teaching are all helpful approaches to improve both memory and reasoning of the knowledge. 

Spaced repetition and interleaving are the best tactics for remembering. 

Deliberate practices help develop complex and mature knowledge domains. 

Caffeine and nicotine are double-edged swords and generally have adverse effects in the long run. 

Music, games, meditation, and diets are either ambiguously or weakly correlated with cognition acuity. However, they all seem to have adverse effects if done improperly.