Self Help

How We Learn - Benedict Carey

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Matheus Puppe

· 39 min read

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  • This is the introduction to the book “How We Learn: The Surprising Truth About When, Where, and Why It Happens” by Benedict Carey.

  • The author describes his experience as a “grind” in high school, studying hard but feeling insecure. He questions if there is a better approach to learning.

  • In college, he adopted a more relaxed approach, mixing study with other activities. He later realized this approach aligned with findings from cognitive science on effective learning techniques.

  • As a journalist, the author reported on studies showing counterintuitive findings on things like distractions, naps, breaks, and tests aiding learning. These findings prompted him to experiment with different learning approaches.

  • The book aims to explain how findings from the science of learning and memory fit together as features of the brain’s learning system. The author sees his college experience in a new light, allowing topics to integrate into his life in a way that revealed the brain’s strengths and limitations as a learning machine.

The passage discusses how memory and learning work at the biological level in the brain. It notes that the brain has over 100 billion neurons that are constantly forming interconnecting networks. During sleep, parts of the brain remain highly active, searching for meaning and connections from the day’s events.

The brain prefers meaning over randomness and finds nonsense offensive. It remembers some details well, like movie scenes, but forgets important facts for exams. So the brain is an eccentric learning machine that works best when its quirks are exploited.

Recent research has uncovered techniques that deepen learning without requiring special software or long periods of repetitive practice. Things like varying study locations and mixing related tasks can improve recall more than sticking to one dedicated study space or practicing a single skill repetitively. Distractions may actually help learning in some cases by helping us shake free of being stuck.

There is no single right way to learn - different strategies suit different types of information. A good approach is to tailor the learning technique to the specific information being learned. The passage aims to outline the theory and findings from the science of learning that have stood up to scrutiny, in order to improve how people learn in their daily lives.

  • The passage uses a metaphor of a documentary film crew to represent what is happening behind the scenes in the brain as memories are formed and retrieved.

  • It discusses how metaphors can be imprecise but serve to dramatize important concepts. In this case, the film crew metaphor represents scientists’ current understanding of the brain biology involved in memory.

  • It then discusses specific research in which electrode implants were used to directly record brain cell firing patterns as human subjects viewed and later recalled video clips. The same patterns were observed, showing memories are encoded in neural networks.

  • The passage goes on to describe a vivid personal memory from the author’s first day of high school in rich sensory detail, showing how episodic memories are retrieved.

  • It provides background on the evolution of scientific understanding of memory formation and storage in the brain, moving from a view of memories being diffuse to recognizing specific brain areas are involved. A pivotal case study is described that helped uncover the role of the hippocampus in forming new memories.

  • In 1953, a man named Henry Molaison (later known as H.M.) sought treatment for severe epilepsy from neurosurgeon Dr. William Scoville at Hartford Hospital. Antiseizure drugs were not working well for Molaison.

  • Scoville performed surgery to remove parts of Molaison’s medial temporal lobes, including the hippocampus, as he believed the seizures originated there. The surgery greatly reduced seizures but left Molaison unable to form new memories.

  • Psychologist Brenda Milner began working with Molaison in 1953 to study his amnesia. Her experiments showed he could not remember new information or experiences but could learn new motor skills through repetition.

  • Milner’s work established that there are different brain systems for conscious and unconscious/procedural memory. The hippocampus is necessary for conscious memory formation.

  • Later studies by Milner’s student Suzanne Corkin extended over 40 years and provided more insights into Molaison’s memory impairments and abilities. His case profoundly influenced the understanding of memory in neuroscience.

  • The story highlights how studying brain injury patients like Molaison has advanced scientific knowledge of memory systems in the brain, while also emphasizing the human nature of these individuals.

  • Early studies of split-brain patients in the 1950s found no differences in thinking or perception after the brain was surgically divided.

  • In the 1960s, scientists at Caltech devised experiments to flash pictures to each hemisphere separately. They discovered the right hemisphere could identify objects by image or touch, even if the left hemisphere couldn’t name them verbally.

  • This revealed a division of labor - the left hemisphere was language-based and analytical, while the right was visual-spatial. But the brain still felt unified.

  • In the 1980s, Michael Gazzaniga performed more split-brain experiments. One found that when asked to explain a choice made by the non-verbal right hemisphere, the left hemisphere would make up a story torationalize it.

  • This showed the left hemisphere acts as an “interpreter” or “story maker” to provide a narrative and sense of unity from the different inputs. This module is key to forming memories by answering “what just happened?” in the moment.

  • When recalling memories, the interpreter gathers cues internally and strings them together with associative details to reconstruct the memory, constantly changing and updating it in the process. Using memories actually changes memories over time.

  • The article discusses the concept of the “forgetting curve” proposed by Herman Ebbinghaus in the 1880s, which showed that memory of newly learned information decreases rapidly over time. This challenged the idea that forgetting is a failure and showed it plays an important role in learning.

  • Forgetting allows the brain to focus and filter out irrelevant information, enabling important facts to stand out. Memory competitions actually demonstrate this, as contestants’ sharp focus causes them to forget common knowledge.

  • Forgetting also benefits subsequent learning through the “muscle building” of revisiting material. Without some forgetting, further study provides no benefits.

  • A “new theory of disuse” recasts forgetting as beneficial to learning rather than a rival. Forgetting much of a new topic is normal as the brain works to filter and strengthen memories through further study.

  • Ebbinghaus pioneered the scientific study of memory through rigorous experiments on himself memorizing and recalling lists of nonsense syllables over time, establishing the “forgetting curve” and challenging ideas that forgetting simply means information is lost.

  • Hermann Ebbinghaus used nonsense syllables like “RUR” and “HAL” in his pioneering experiments on memory in the late 1800s. He found that memory fades according to a predictable curve known as the “forgetting curve.”

  • In the early 1900s, Philip Boswood Ballard tested poor students in London and found that their memory actually improved over a few days without practice, contradicting Ebbinghaus’ findings. Ballard called this “spontaneous improvement” or “reminiscence.”

  • Ballard’s findings created confusion and skepticism among psychologists. Further experiments yielded mixed results, failing to consistently replicate spontaneous improvement.

  • The discrepancy between Ebbinghaus and Ballard highlighted that forgetting and remembering are more complex than a single curve or tendency. Memory involves both decay over time but also filtering and integration of new information into existing networks.

  • Nonsense syllables are useless clutter for the brain while meaningful material like poems can integrate into webs of related concepts, potentially improving recall over time in a way nonsense cannot. However, the exact mechanisms of spontaneous improvement remain unclear.

  • Ballard, an early 20th century researcher, found that children were able to recall more of a memorized poem when tested a few days later, without rehearsing in between. This became known as the “Ballard effect” or “spontaneous improvement.”

  • Initially many dismissed Ballard’s findings as a fluke or flaw in his experimental design. However, later researchers were able to replicate the effect, showing it was real.

  • The improvement over time is likely not due to children rehearsing on their own. You can’t practice what you don’t remember.

  • The Ballard effect is stronger for imagery-rich material like poetry and pictures, compared to nonsense words or random sentences. It takes time (a day or two) for the improvement to occur.

  • Modern research has helped explain the Ballard effect. It’s due to separate memory storage and retrieval strength mechanisms. Storage strength (how well learned something is) increases with study and never decreases. Retrieval strength (how easily it comes to mind) is weaker and decays faster without practice. The delay between tests allows retrieval strength to improve again.

So in summary, the Ballard effect showed memory spontaneously improving over time is real, and modern theories explain it in terms of separate storage and retrieval memory mechanisms. It was not simply a flaw in Ballard’s original experimental design.

  • The passage discusses the idea that being in the same mental or physical state during studying as during a test can help with memory retrieval and exam performance.

  • As students, the author and their friends believed that taking “brain vitamins” or study aids before studying and before tests put them in the same “brain chemistry” and helped them recall more. While this was likely just rationalization, it fits with common advice to develop consistent study habits and rituals.

  • Consistency in study habits, like having a dedicated study space and time, has been promoted in education manuals for over a century. The idea is that being in the same context helps cue memory retrieval.

  • Developing rituals and always studying in the same way and place is meant to put one’s mind in the same state during the test as it was during studying. This context or state-dependent learning effect is thought to help bring more information to mind on the exam.

  • While their “brain vitamins” were likely just energizing and not truly improving memory, the basic idea of context aiding recall aligns with theories of how cueing and state-dependent memory work.

  • Using earplugs or a headset can help block out noise to stay focused while studying. Saying no to people who try to alter your study time can also help with consistency.

  • Some research has found that people may perform better on tests if they study and take the test in a similar mental state, like being mildly intoxicated or stimulated from substances both times. Mood, environment and other contextual factors can influence learning and recall.

  • A study by Godden and Baddeley in 1975 found that scuba divers remembered more words when they took a memory test underwater versus on land, supporting the idea that being in the original study environment (“reinstatement”) can aid recall.

  • Further experiments explored how contextual cues like background music, lighting, locations can influence memory on word list and other semantic memory tasks. Being in the same context for study and test generally produced better recall than different contexts.

  • Consistency in study methods and limiting distractions can help optimize learning, but the contextual details of the study experience may also play a subtle role in memory through retrieval cues, challenging the view that context doesn’t matter.

  • The passage describes an experiment conducted in 1975 that tested the effects of marijuana on memory retention.

  • 30 college students were recruited and split into two groups. One group smoked a real marijuana joint, while the other smoked a placebo joint.

  • While moderately high, both groups studied lists of 48 words grouped into categories.

  • 4 hours later, after the effects of the drug had worn off, they smoked again - some smoking real/placebo and vice versa.

  • 20 minutes later they took free recall and cued recall tests.

  • Those who smoked real joints both times remembered 40% more words on the free recall test than those who smoked real/placebo.

  • Cued recall scores were uniformly high regardless of drug use.

  • This suggests the brain stores the same number of words high or not, but organizes them differently for later retrieval. Memories were best retrieved when the brain state matched during study and testing.

In summary, the experiment provided evidence that marijuana can produce state-dependent memory - memories are best recalled when the internal mental state matches during encoding and retrieval.

  • A study found that people recalled words better (40% improvement) when they studied the words in two different rooms rather than staying in the same room both times. Encoding memories in varied contexts with different external cues helped later retrieval.

  • Researchers had participants study a list of words in either the same small basement room twice, or in that room once and another room the second time. Later recall was tested in a new, neutral room.

  • Those who studied in two different rooms recalled on average 8 more words out of 40 than those who stayed in the same room. Simply changing venues enhanced memory strength.

  • This shows that encoding memories with more varied external cues, rather than just internal mental states, can boost later recall when those cues are not reinstated at test. Varied contexts provide more retrieval routes to the memory.

  • The study illustrates how incorporating more environmental details into memory encoding, beyond just the to-be-remembered facts, can create a more durable memory trace with more pathways for later recollection.

The passage discusses research on the spacing effect, which refers to distributing or spacing out study time rather than concentrating it all at once. Studies have found that spaced learning leads to better retention of material over time compared to massed learning in one sitting.

  • Spacing out study in multiple short sessions, like 30 minutes a few times a week for lawn watering, is more effective than doing it all at once in a longer session.

  • Spaced learning can double the amount of material retained later on compared to massed learning.

  • However, cramming may still improve exam performance short-term, even if retention falls off quickly afterwards.

  • While known for over 100 years, spacing has not been widely adopted in education, perhaps due to challenges implementing multiple study sessions.

  • Research is still exploring the optimal spacing intervals - whether daily, every other day, weekly, etc. depending on the exam date.

  • The history of spacing research shows how evidence builds slowly in science through replication and extension, but this has prevented real-world application in some cases.

So in summary, the passage discusses the well-established cognitive benefits of distributing or spacing out study time found in memory research.

  • Harry P. Bahrick conducted a landmark long-term study of the spacing effect on learning foreign language vocabulary, using his wife and daughters as subjects. They studied lists of French/German words on different schedules - every 2 weeks, 1 month, 2 months, etc. - over many years.

  • This was a departure from previous spacing effect research that only looked at very short time intervals like minutes or seconds. Bahrick wanted to test real-world relevant periods like weeks and months.

  • The “Four Bahrick Study” was the first to truly examine the long-term impact of spacing on building mastery over foreign language vocabulary. It helped establish that distributed practice over long periods boosted retention much more than mass practice.

  • Piotr Wozniak calculated that at the rate he was going, he would need to study English 4 hours a day for years to become proficient enough to read scientific papers. This motivated him to develop a more efficient spaced repetition study system using himself as a test subject.

  • Piotr Wozniak experimented with different spaced repetition schedules to learn English vocabulary words. He found that reviewing words after 1 day, then 1 week, then 1 month was most effective for long-term retention.

  • He developed this into SuperMemo software, which uses an algorithm to schedule reviews just before words are forgotten. This “spacing effect” approach became popular for vocabulary learning.

  • Later studies showed longer intervals were even better - reviewing every 2 months led to the highest retention rates over multiple years. This reinforced the power of spaced repetition.

  • While spaced repetition clearly improves learning, questions remained about calculating optimal intervals depending on the material and test date.

  • A 2008 study helped answer this by testing different review intervals before a factual quiz. They found reviewing study material twice, with either a 10 minute or 1 week interval before the test, led to significantly better scores than a single review.

So in summary, this outlines the discovery and reinforcement of the spacing effect principle through various experiments, and how it informed the development of spaced repetition software and strategies to maximize long-term learning.

  • The researchers conducted a study comparing 26 different study schedules that varied the interval between study sessions (from 1 day to 6 months) and the timing of the final exam.

  • They found that the optimal interval between study sessions depends on how far in advance the exam is. Shorter intervals (1-2 days) are best if the exam is within a week, while longer intervals (3-5 weeks) are best if the exam is 6 months away.

  • In general, the optimal first interval is 20-40% of the total time until the exam. Intervals longer than that see performance decline quickly.

  • For example, if an exam is 3 months away with 9 total study hours available over 15 days, the optimal schedule would be 3 hours on day 1, 3 hours on day 8, and 3 hours on day 14.

  • The key takeaway is that spacing out study sessions over time leads to better retention and exam performance than cramming, even if the total study time is the same. Spacing relies on the “desirable difficulty” principle - harder retrieval strengthens memory more than easy fluency.

  • Testing and self-examination have long been recognized as effective learning techniques, with philosophers like Francis Bacon and William James writing about their benefits in the early 17th and late 19th centuries respectively.

  • In 1917, psychologist Arthur Gates conducted an experiment with schoolchildren to determine the optimal ratio of time spent reading vs reciting passages to memorize them. He found that spending around 40% of time reading and 60% reciting led to the best retention.

  • Though a landmark study, Gates’ findings did not receive much attention or follow-up research at the time.

  • In the late 1930s, Herbert Spitzer came across Gates’ study while searching for a dissertation topic. He recognized Gates’ recitation technique as a form of self-testing.

  • Spitzer then conducted the largest “pop quiz” experiment to date with over 3,600 students, testing the efficacy of periodic quizzing at different intervals after material was learned.

  • The experiments by Gates and Spitzer were early demonstrations of the powerful benefits of self-testing and periodic assessment for improving learning retention, though their full significance was only recognized later through retrospective analysis.

  • A study by Spitzer in the 1920s found that student groups who took pop quizzes soon after reading a passage scored better (around 50%) on a final exam two months later, compared to groups who took their first quiz two weeks or more later (below 30%).

  • Testing serves as an effective study technique that strengthens retention if done shortly after initial learning. Repeated testing helps with long-term retention more than restudying.

  • Psychologists in the 1960s-70s like Izawa also found testing effects, but Roediger and Karpicke’s 2006 studies helped emphasize the power of testing for learning different types of material.

  • One of their experiments showed students learned a science passage better if they took a free recall test on it later, compared to restudying it. Testing led to better retention over time, especially after a week.

  • While others had found the “testing effect” before, Roediger and Karpicke helped show its application to real classrooms and material. However, debate around standardized testing has prevented these findings from being widely applied in education.

  • Researchers have begun calling testing “retrieval practice” to soften resistance to it. This phrase highlights that testing engages retrieval of information from memory in a way that studying does not.

  • Testing represents a “desirable difficulty” that deepens learning compared to restudying. Retrieving information strengthens memory storage and connections in the brain.

  • “Pretesting” refers to taking practice tests on material not yet covered. Studies show that even wrong answers on pretests can boost later test performance, suggesting they engage and direct learning.

  • A classroom study gave students pretests before some lectures. A later cumulative exam included related and unrelated questions. Students scored higher on related pretest questions, indicating pretesting enhanced comprehension and retention of that material compared to non-pretested content.

The key idea is that retrieving or attempting to retrieve information through practice testing, even if incorrect, enhances subsequent learning and memory compared to conventional studying alone. Pretesting appears to direct attention and engage retrieval processes in a way that primes the brain for deeper encoding.

Based on the information provided:

Which of the following is true of explanations based on belief?

The answer is e) b and c above.

Explanations based on belief are:

b) accepted because they come from a trusted source or authority figure.

c) assumed to be true absolutely.

The passage states that explanations based on belief are accepted either because they come from a trusted source/authority figure (b), or are assumed to be absolutely true (c).

The other answer choices are not consistent with descriptions of explanations based on belief provided in the passage:

a) They are not necessarily more likely to be verified by empirical observation.

d) In the face of evidence inconsistent with the belief, the belief may not be questioned.

So the most accurate answer is e) b and c above, as these capture the two characteristics described for explanations based on belief in the passage.

Here is a three-point summary:

  1. The problem presented was to arrange six pencils into four equal triangles. This is an “insight problem” that requires shifting perspective to solve, rather than using standard math approaches.

  2. Most students tried initial solutions that did not work by drawing triangles inside of each other. One student then suggested using the number four and a triangle, which provided an unconventional but correct solution.

  3. Insight problems force students to let go of initial ideas, reexamine all information, and think more creatively. The story highlights how unconventional ideas sometimes lead to solutions, even if they seem “off-base” at first. It promotes creative problem-solving over only linear, deductive reasoning.

  • Wallas proposed a four-stage model of creative problem solving: preparation, incubation, illumination, and verification.

  • Preparation involves understanding the problem and exhausting initial ideas. Incubation begins when work is set aside. During this stage, subconscious mental processes occur, reorganizing and associating information.

  • Illumination is the “aha!” moment when the solution appears suddenly. Verification checks if the solution is correct.

  • Wallas saw incubation as a less intense continuation of work, where the mind plays with concepts subconsciously like working a puzzle. This letting go allows the subconscious to work without conscious interference.

  • Psychologist Norman Maier studied incubation through puzzles involving objects rather than symbols. His experiments showed incubation is often entirely subconscious - hints provided during breaks were not consciously perceived but still helped solutions emerge suddenly in illumination. The brain scans clues in the environment subconsciously during incubation.

  • Karl Duncker conducted experiments where he would subtly block or remove obstacles to creative problem solving without participants noticing. His most famous example was the candle problem.

  • When boxes on the table were full, participants saw them as containers and not potential platforms to place candles on. Emptying the boxes allowed participants to see the boxes could be used to support candles, unblocking their thinking.

  • Duncker found that objects not “fixed” in someone’s mental representation were almost twice as easily incorporated into problem solving than fixed objects.

  • Maier and Duncker uncovered two mental operations that aid incubation - picking up clues from the environment and breaking fixed assumptions. However, most people don’t have a psychologist available to provide hints when stuck.

  • Later research explored questions like how long should a break be, what type of break works best, and if different problems require different break activities. Over 100 experiments tested incubation durations and break activities like games, reading, and daydreaming. The optimal break may depend on the specific problem and hints provided.

  • Smith and Blankenship conducted an experiment using Remote Associates Test (RAT) puzzles to test the effects of incubation and hints on problem solving.

  • Subjects given misleading hints (“fixed”) solved fewer puzzles initially than those without hints.

  • After a break, those who had misleading hints showed improved problem solving, solving around twice as many puzzles, suggesting the break allowed them to overcome the fixedness caused by the bad hints.

  • The authors proposed this was due to “selective forgetting” - the misleading hints temporarily blocked other solutions, but the break allowed this retrieval block to wear off.

  • A meta-analysis found incubation effects are real but vary by problem type and break activity. Relaxing or mild activities like games aided linguistic problems most.

  • Longer breaks (~20 mins) worked better than short ones (~5 mins), but people only benefit after reaching an impasse on a problem.

  • The research suggests breaks that allow distraction, within reason, can aid problem solving by overcoming fixation and allowing new ideas to surface through selective forgetting or free association.

  • The passage discusses incubation and percolation as two modes of solving problems. Incubation refers to short breaks (5-20 minutes) that can help solve well-defined puzzles or logical problems.

  • Percolation refers to a longer-term, cumulative process that is needed to solve more complex, protracted problems like creative projects. It involves taking repeated breaks over hours, days or longer.

  • Creative writers like Joseph Heller and A.E. Housman describe experiences where new ideas or pieces of their work would come to them in fragments during downtime, often when tired or relaxed.

  • These ideas would come piecemeal, not fully formed, and would need to be worked and developed further. But taking breaks was important for new thoughts to surface from subconscious processing.

  • The passage argues creative problem-solving for complex projects operates through a process of percolation, not just isolated incubation breaks. It draws on social psychology to help explain this longer-term model of generating new ideas or solutions.

In summary, it distinguishes between incubation for well-defined puzzles and percolation as a longer-term, iterative process needed for more open-ended creative work, as described by writers who have experienced this process.

  • Psychologist Kurt Lewin observed waiters at a cafe who could remember food orders until they were paid, then immediately forgot them. This led to the idea that unfinished tasks may linger longer in memory.

  • Bluma Zeigarnik, one of Lewin’s students, conducted experiments showing that interrupted or unfinished tasks are remembered much better than completed ones. This became known as the Zeigarnik effect.

  • Goals, even small short-term ones, seem to automatically engage our mental attention and memory according to this effect. Interrupting ourselves when absorbed in a goal prolongs how long we stay focused on it.

  • The Zeigarnik effect showed that the mind has built-in biases to prioritize unfinished goals and tasks. This discovery helped establish our understanding of how goals form and function psychologically.

  • Deliberate self-interruption, like cliffhanger endings, exploits this bias to prolong engagement with long-term goals and creative works like novels or TV shows. It keeps goals actively on our mind.

  • Further experiments confirmed that having an active, unfulfilled goal changes our perceptions and behaviors in subtle ways, like increasing thirst in those given taste samples. The mind orients itself towards goal completion.

The passage describes an experiment conducted by psychologists to demonstrate how basic needs and motives can influence perceptions and memory. Participants were split into two groups - one group was given a drink that heightened their thirst, while the control group was not. They were then brought to an office room and asked to recall as many objects in the room as they could after 4 minutes.

The group that was made thirsty remembered twice as many drink-related items compared to the control group, even if they weren’t consciously aware of why. This showed that having a goal like quenching thirst “tunes our perceptions” to notice things related to fulfilling that goal. Later studies showed this principle applies to any active goal - we become more attuned to noticing related cues in our environment.

The passage then discusses how academic goals can similarly tune our perception and thinking. When working on a research paper, we become more aware of details and examples connected to our topic. Small insights gathered from everyday experiences, like overhearing conversations, can provide useful fodder and move our thinking forward incrementally. The key is having our goal or topic activated at a high level in our minds to maximize this effect.

Here are three summaries responding to the prompt:

  1. Interview with an expert An interview with Dr. Sarah Johnson, a professor of environmental science at State University. Dr. Johnson discusses her research into landfill leachate and its potential health impacts. She analyzes water samples near landfills to test for contaminants and track their movement through local watersheds. While more study is needed, her preliminary findings suggest certain compounds from decomposing waste may pose long-term risks if exposure levels are high. The interview provides valuable first-hand insight from an expert actively investigating this issue.

  2. Defining a key term
    One key term in debates around solid waste disposal is “landfill leachate.” Landfill leachate refers to the liquid that drains or “leaches” from decomposing garbage in a landfill. As waste breaks down, this leachate can dissolve chemicals, metals, and other pollutants. If not properly contained and treated, leachate poses environmental and health risks if it contaminates soil and groundwater. Understanding leachate formation and how it transports pollutants is crucial for evaluating different solid waste strategies and their environmental impacts.

  3. Response to a controversial school of thought A response critiquing the “not in my backyard” (NIMBY) perspective sometimes found in communities opposing new landfill development. While concerns over property values and neighborhood aesthetics are understandable, the NIMBY view can undermine good-faith efforts to site modern, closely regulated landfills meeting stringent environmental standards. A nimbyism taken to an extreme results in a tragically fragmented waste management system as no community volunteers to accept any facilities. A more constructive approach recognizes the need for responsibly managed, scientifically selected sites to handle our collective trash.

The passage discusses an early study from 1978 that challenged existing beliefs about practice and learning. Researchers Robert Kerr and Bernard Booth found that a group of children who practiced blind bean bag tossing on varied targets performed better on a final test than a group who practiced on a single, consistent target. This went against the prevailing view that repetitive, focused practice was most effective.

The study was largely ignored at the time. In the early 1990s, Richard Schmidt and Robert Bjork reexamined the literature and found other studies with similar results. One studied showed women who practiced three types of badminton serves with varied/random schedules improved more than those with blocked, repetitive practice schedules.

This suggested that varied, interrupted practice may be more effective than repetitive, focused practice alone. The passage discusses how this challenged long-held divisions between motor learning and conceptual/verbal learning approaches in psychology. It hints that combining these perspectives revealed new insights about effective practice and how the brain learns new skills.

This passage summarizes a key principle of skill mastery and effective practice: varied or interleaved practice leads to better long-term learning and transfer of skills compared to blocked or repetitive practice.

  • Studies show that mixing up different types of practice (e.g. serving different types of volleyball shots randomly rather than repeatedly) leads to better performance on transfer tests where the context is changed (e.g. serving from the opposite side of the court).

  • Varied practice forces continual adjustments that build general dexterity and help each specific skill, leading to stronger transfer of skills to new contexts.

  • Repetitive practice may lead to quicker improvements during practice but plateaus more quickly over the long run compared to varied practice.

  • Psychologists Harry Pascual-Leone, Robert Bjork and Richard Shiffrin showed through experiments that varied practice enhances learning in both physical and cognitive skills like remembering names or art appreciation.

  • Varied practice introduces “desirable difficulties” that make learning harder in the moment but strengthen long-term retention and ability to apply skills flexibly in new situations. This is a more effective approach than repetitive practice that produces surface-level learning.

So in summary, the passage discusses evidence that varied or interleaved practice tends to be a more effective approach than repetitive practice for developing skills that thoroughly mastered and can be applied flexibly.

  • Researchers conducted an experiment to test whether interleaved (mixed) study of paintings by different artists led to better aesthetic judgment compared to blocked (grouped) study.

  • Participants studied paintings by 12 artists, either grouped by artist or mixed. They were later tested on matching new paintings to their artists.

  • The mixed study group performed significantly better, correctly identifying the artist for 65% of paintings compared to 50% for the blocked group. Subsequent trials replicated this result.

  • Interleaving appears to help distinguish between related concepts and grasp each individually better. However, people overwhelmingly believe blocked study helps learning more.

  • The US lags in math education compared to other countries. In the late 1980s, there was a debate between those favoring abstract, top-down teaching vs procedural, bottom-down teaching.

  • A teacher, Doug Rohrer, noticed students did poorly on cumulative exams despite doing well on weekly tests. He theorized this was because exams required choosing strategies, not just applying them.

  • Rohrer considered developing a mixed problem curriculum. However, someone already had - John Saxon, who created a textbook mixing different math topics into daily assignments.

  • John Saxon developed Saxon Math textbooks in the 1980s-1990s as an alternative to the standard math curriculum approach at the time.

  • His innovation was “mixed review” - homework assignments included new material along with problems from previous lessons. This was meant to gradually build algebraic skills in a more incremental way.

  • Saxon believed mixing familiar and new problems helped students better grasp new techniques by using them alongside old, familiar ones.

  • His mixed review approach built on the idea of “interleaving” - mixing different types of problems rather than practicing the same type repeatedly.

  • Rohrer, the author, was initially skeptical of Saxon’s non-logical textbook organization but was interested in the mixed review/interleaving approach to help his own students distinguish problem types.

  • Rohrer later conducted his own experiments showing interleaving can improve math comprehension. His 2007 study with 4th graders on geometry problems directly compared blocked vs interleaved practice. Interleaved practice led to better test scores.

  • Interleaving forces students to identify problem types and match them to solutions, improving their ability to do so on exams which also include varied problems. This discrimination skill is important for math learning.

  • Batters have around 250 milliseconds to decide whether to swing at a pitched baseball. In that time, their brain must assess the velocity, trajectory, spin, and type of pitch based on cues like the ball’s image and the pitcher’s release point and body language.

  • Despite extensive training, hitters struggle to consciously describe how they evaluate pitches. Some report seeing a “red dot” or “grayish blur” to identify breaking vs fastballs.

  • Cognitive scientist Steven Sloman notes experts like batters develop an “infrared lens” to subconsciously extract meaningful visual clues through extensive experience, akin to the abilities of chess grand masters.

  • In the 1940s-50s, psychologist Eleanor Gibson challenged the dominant “stimulus-response” view of learning, which saw it as linking sensory inputs to behaviors. She argued learning also involves discriminating subtle differences.

  • Gibson conducted classic experiments showing young children can quickly distinguish standard letters from distorted ones, before attaching meaning. This challenged the idea that learning only involved associations, not discrimination skills. Her research helped broaden understanding of the learning process.

  • Eleanor Gibson conducted an experiment where participants had to identify exact replicas of doodles from similar looking near-replicas. Adults needed about 3 rounds, older children 5 rounds, and younger children 7 rounds to identify all replicas without error. This showed perceptual learning is an active process where the brain learns to discriminate subtle differences.

  • Gibson proposed a theory of perceptual learning, where the brain extracts distinctive features from sensory stimuli to perceive and learn. It is an active, self-regulated process of discovering structure without external reinforcement.

  • Philip Kellman was inspired by Gibson’s work while learning to fly. He observed how expert pilots can instantly perceive patterns from aircraft instruments that novices cannot. Reading all instruments takes significant training.

  • Kellman developed a perceptual learning module (PLM) computer program to help novices develop a gut feeling for what the instruments indicate before flying. The program gives instrument panel lessons to improve basic perception of combinations like “straight and level” vs “descending turn.” The goal is to reduce stress for novices in actual flight.

So in summary, the passage discusses Gibson’s evidence for active perceptual learning and how her theories influenced Kellman to develop training methods focused on improving basic perceptual skills for pilots.

  • Researchers tested a perceptual learning module (PLM) for improving skills in identifying aircraft instrument panels. Both experienced pilots and novices trained on the PLM, which showed instrument panels and required quick identification of readings.

  • After only one hour of training, even experienced pilots improved in speed and accuracy. Novices’ performance increased dramatically, allowing them to read panels as well as pilots with 1000 hours of experience, in 1/1000th of the time.

  • Similar results were found for a PLM training visual navigation skills. PLLs seem effective for accelerating acquisition of skills in aviation and other fields involving visual discrimination.

  • Kellman and others have developed PLMs for skills in other domains like medicine, chemistry, and math. Studies found PLMs significantly improved students’ abilities to identify skin lesions, interpret medical images, analyze chemical bonds, and match equations to graphs.

  • The author tested a PLM created by his daughter to help him distinguish artistic styles and movements. Through spaced, interleaved practice over multiple sessions, he was able to progress from barely recognizing Impressionism to identifying 12 different styles, even styles not directly trained on.

  • While more research is needed, PLMs show promise as a supplement for accelerating acquisition of visual discrimination and categorization skills in various fields of expertise. They build “perceptual intuition” through high-exposure, rapid-feedback practice.

  • Sleep plays an important role in consolidating memories and facilitating learning. Studies have found sleep helps strengthen important memories and make subtle new connections about problems or skills learned during the day.

  • One theory is that sleep evolved as a time management adaptation. Our circadian rhythms keep us asleep when there is little activity/food availability (like late night) and awake when there is more opportunity (daytime). This helps conserve energy at unproductive times and maximize it when needed.

  • Animal sleep patterns vary greatly depending on lifestyle and needs. Some can go weeks without sleep like migrating birds, while brown bats sleep 20 hours a day and are only awake the 4 hours at dusk when food is abundant.

  • The purpose of sleep is still not fully understood, as no single theory can explain all the variations. Both memory consolidation and a time management adaptation may play roles in why we sleep. Sleep deprivation impacts mood, concentration, healing and possibly infection risk.

  • Stories of scientific discoveries made during sleep, like the structure of benzene in a dream, support the idea sleep helps make unconscious connections. People often report solving problems or having ideas in the middle of the night.

The primary function of our unconscious minds during sleep is learning and memory consolidation. While sleeping, the brain is actively processing memories and information learned during the day in order to strengthen connections between neurons and embed this new knowledge into long-term memory stores.

  • Sleep was originally thought to be a passive period where the brain “powers down”, but research has shown the brain is highly active during sleep, especially during REM sleep.

  • REM sleep occurs in cycles throughout the night, with periods of increased brain activity and eye movement alternating with non-REM sleep stages.

  • Discovery of this “sleep architecture” demonstrated the brain is not powering down but rather actively working on something during sleep.

  • Further research sought to determine what exactly the brain is doing - nature does not expend resources without purpose or function.

  • Learning abilities like hierarchical reasoning demonstrate how the brain consolidates new information during sleep to build understanding and develop logical connections.

So in summary, while we sleep, our unconscious minds are critically important for facilitating memory consolidation and learning by strengthening neural connections formed during waking experiences.

  • Two groups of students were tested on memorizing the ranking of pairs of items (eggs with different colors). One group studied in the evening and was tested the next morning after sleep. The other group studied in the morning and was tested in the evening without sleeping.

  • The group that slept performed much better on the harder questions that tested relationships between items they didn’t directly study, scoring 93% vs 69% for the group without sleep.

  • Scientists believe sleep helps form a “bigger picture” and build associations between different categories. Sleep consolidates learning and helps see relationships that weren’t clear before.

  • Different stages of sleep may consolidate different types of learning - REM helps pattern recognition and creative problem-solving, stage 2 helps motor skills, deep sleep helps factual recall.

  • The “Night Shift Theory” proposes each sleep stage has a specialized role in memory consolidation, helping different abilities like motor skills, emotional memories, pattern recognition, and factual recall.

  • Getting the right doses of each sleep stage may help optimize learning for different tasks like tests requiring recall vs problem-solving abilities. Napping can also provide sleep’s learning benefits.

  • Sara Mednick found that naps of 1-1.5 hours often contain deep sleep and REM sleep, which are important for memory consolidation and learning.

  • In studies, people who learned material in the morning and then took a 1-hour nap performed about 30% better on evening tests compared to those who didn’t nap.

  • Mednick says naps of 1-1.5 hours can provide similar benefits to memory consolidation and learning as a full 8-hour night of sleep. Naps effectively “refresh” the memory of material learned earlier in the day.

  • The researcher’s findings suggest naps can enhance and solidify the learning process in an important way, changing how students and professionals can optimize their studying, learning and work. Regular naps were found to significantly boost later recall and understanding of material.

  • Natural human learning is informal and occurs through daily experiences like exploring, observing peers and elders, and accumulating information through foraging and adapting to the environment. This helped the brain develop efficiently to absorb survival skills.

  • Humans evolved to outsmart competitors by developing tools, theories, traps, etc. to dominate the “cognitive niche”.

  • Modern education grew out of these natural learning modes but its structure of segmented classes/times doesn’t fully match how the brain naturally learns in an integrated way throughout the day.

  • The idea of “concentration” is idealized and blurred - observing one father working closely showed he was easily distracted with breaks, yet still effectively completed his work.

  • The brain’s neural networks for navigation evolved to help learn academic/motor skills, though not necessarily perfectly adapted yet. Being confused can motivate pattern recognition and meaning-making.

  • The author realized cognitive science findings could help broaden and practicalize learning beyond structured education through meaningful tactics based on natural learning processes. This could make effective learning more accessible.

  • We can’t control many aspects of our environment and upbringing like our genes, family, teachers, where we go to school. But we can control how we learn.

  • The science shows that spaced, interleaved learning in short bursts throughout the day, rather than laser-focused marathon sessions, leads to more efficient and deeper learning. This provides relief that we don’t have to devote all our time to intense studying.

  • “Distractions”, interruptions, breaks are not deviations from purposeful learning - they are part of life and our daily existence. Our study habits should integrate these aspects of life rather than try to avoid them.

  • Forgetting is as important to learning as remembering. It allows our memories to strengthen over time. Techniques like spacing out study and leaving things unfinished take advantage of this.

  • Applying learning science principles hasn’t made the author a genius but has made him more comfortable with his limitations and given him better study habits.

  • Looking at learning scientifically has become a way of living for the author. The techniques are effective and easily applied in real life to optimize learning given our natural constraints and environments.

  • In the future, specific learning techniques may be tailored more to different topics and contexts. But the primary focus should remain on optimizing learning within our everyday lives and circumstances.

  • Self-testing through flashcards, quizzing oneself, or having others quiz you is one of the strongest study techniques. It forces retrieval of information from memory and provides feedback, both of which greatly improve retention compared to just reviewing materials.

  • Reviewing notes is most effective when it involves recalling or explaining the material without looking, rather than just re-reading or looking over highlighted parts. This engages memory more deeply.

  • Short study breaks of 5-10 minutes to check social media, email, etc. can actually aid learning by providing mental relaxation and allowing the subconscious to continue working on problems.

  • Starting long-term creative projects early and giving yourself permission to step away from them periodically helps the ideas “percolate” in your mind and allows you to return with a fresh perspective.

  • The illusion of “knowing” material because it seems easy at the time of study is called “fluency.” Self-quizzing exposes gaps and prevents this illusion from forming.

  • For building skills, mixing practice of different skills (“interleaving”) leads to better long-term retention than focusing on one skill at a time, even though focused practice yields quicker visible improvement.

  • The most common reason for doing poorly on a test after feeling prepared is falling for the fluency illusion - not realizing gaps in one’s understanding or ability to retrieve information.

Here is a summary of the sources provided:

The passage discusses several classic studies on memory and problem solving that involved some element of distraction or incubation.

  • Source 1 discusses the famous German psychologist Hermann Ebbinghaus, who in the late 19th century conducted early experiments on forgetting curves by testing himself on lists of nonsense syllables.

  • Source 2 provides historical context on Ebbinghaus’ experiments and discusses how he conducted his research in working-class London neighborhoods.

  • Sources 3-7 discuss several early 20th century studies that found evidence of reminiscence or spontaneous improvements in memory over time, going against Ebbinghaus’ findings of monotonic forgetting. However, later studies like those cited in Source 7 found evidence of continued forgetting over longer periods.

  • Sources 8-12 discuss the origins of research on state-dependent learning and memory in the 1930s-40s and how one’s emotional state at encoding can impact later recall, depending on their state at test.

  • Sources 13-18 discuss a famous case study of an individual with exceptional memory, known as Shereshevsky, who was studied by Russian psychologist Alexander Luria in the 1920s-30s.

  • Sources 5-6 also reference classic experiments from the 1930s-40s that found evidence that changing contexts between study and test can disrupt recall.

  • The passage concludes by discussing several influential 20th century studies of creative problem solving and insight that involved elements of distraction, incubation, or changing mental contexts between attempts at solution. These include works by Wallas, Poincare, Maier and Duncker.

Here is a summary of the contents of the article:

  • The article discusses the cognitive processes involved in learning. It covers 10 chapters that explore various aspects of learning like the spacing effect, deliberate practice, contextual interference, sleep-dependent memory consolidation, and more.

  • Each chapter discusses research studies and findings related to the topic. Researchers cited include Margaret Scranton, Ulric Neisser, Robert Bjork, William James, Eleanor Gibson, and others.

  • Examples are given to illustrate learning concepts, like how musicians practice, chess masters remembering games, pilots learning instrument panels, baseball batters perceiving pitches.

  • The conclusion discusses how the brain’s learning mechanisms can be viewed through an evolutionary lens, as adaptations for foraging and gathering information from the environment over our developmental history.

  • An “About the Author” section notes that Benedict Carey is an award-winning science reporter at The New York Times who has a bachelor’s in math and master’s in journalism from Northwestern University.

So in summary, the article provides an overview of key concepts in the science of learning, as discussed across 10 chapters that integrate various research studies on topics like spacing effects, contextual interference, sleep-dependent memory consolidation, and more.

Here is a one sentence summary:

Benedict Carey is a science journalist who has written about health and science for twenty-five years and lives in New York City.

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