Help Your Working-memory Capacity

I just read a fascinating book on increasing teacher awareness of the importance of working-memory capacity for teaching and learning strategies. Many youngsters have working memory limitations, and they usually do not grow out of them. This is a major and serious cause of low grades, poor learning skills, poor confidence, and life-long diminished motivation to learn.

Limited working-memory capacity impairs the ability to think and solve problems. I was told once by a middle-school teacher that her “special needs” students could do the same math as regular students, but they just can’t remember all the steps. This clearly reflects a limited working-memory capacity. If the demands made on working memory could be lessened, better thinking could result.

Certain strategies can help to reduce the load on working memory. Teachers should model and students should employ the following devices:

• Provide help, cues, mnemonics, reminders.

• KISS (Keep It Simple, Stupid!)(example: use short, simple sentences, present much of the instruction as pictures/diagrams).

• Don’t present so much information. Less can be more.

• Facilitate rehearsal, using only relevant information and no distractors.

• Get engaged, by taking notes, and creating diagrams and concept maps.

• Attach meaning from what is already known. (The more you know, the more you can know).

• Organize information in small categories.

• Break down tasks into small chunks. Master each chunk sequentially, one at a time.

Doing these things not only helps the thinking process, but will also promote the formation of lasting memories. The process of converting working memory into permanent form is called consolidation, and I will explain that next time.

Source:

Gathercole, Susan E., and Alloway, Tracy P. 2008. Working memory and learning. Sage Publications,. 124 pages.

Core Neuroscience Ideas

Readers of this blog who want to have a fuller understanding on how the brain achieves learning and memory may want to know about my new e-book on Core Ideas In Neuroscience.

This modular e-book is a new kind of neuroscience textbook that can liberate professors and students from the boredom of traditional lectures. The book is designed for psychology, medical, allied health, and biology students and professionals who are tired of textbooks that tell them more than they want to know and who don’t want to spend over $100 for their neuroscience book.

This is the fast and inexpensive way to get up to speed on the core ideas in neuroscience.

Benefits for students include: important things are made explicit. Less material is easier to comprehend quickly and to remember. Book’s focus on ideas promotes active learning, critical thinking, insight and understanding. Benefits for professors include: no need to worry about students missing the important information; key concepts are succinctly presented in the book. Class time can be used for more engaging material, such as discussion and debate, clinical case studies, journal club, or design of new experiments. Each of the 75 core ideas is generally treated as a 3-5 page module in which the idea is succinctly stated and explained, with key terms defined. Then, a couple of examples are given, followed by contemporary and classic references. The book has 174 study questions, 96 figures, 545 references (including 306 citation classics), and 566 e-pages. It costs only $11.95, just 16 cents per idea.

Giving Up Can Help Tip-of-the-Tongue States

All of us have had those tip-of-the-tongue (TOT) states where we just can't recall a friend's name or some fact just when we need it. I discuss this phenomenon on pages 198 to 206 of my book. I explain how to deal with this problem by staying calm and trying to recall all the cues associated with what you are trying to remember.


But what if you did not use many cues when you first formed the memory? In those cases, the remedy should perhaps be different. Two psychologists at McMaster University in Ontario recently published a study showing that trying hard to retrieve a TOT memory may be counterproductive. They studied 30 volunteers who were shown definitions to words they did not know. Some definitions were easy, some were hard, and some were fakes. When tested for recall, subjects were instructed to press a button any time they encountered a TOT state. When subjects entered a TOT state they were told to keep trying and they would be told the answer in 10 or 30 seconds if they don't get it.

Subjects were re-tested two days later by being asked to generate the word that fit each definition. Researchers found that subjects had a high probability of stumbling again on the same words they had trouble with the first time. TOTs were almost twice as likely to happen again on words that initially caused a TOT and had been followed by a long delay than on those that had been followed by a short delay. One conclusion is that failing the first time is actually an implicit learning condition wherein subjects are learning to fail again. The longer they kept trying, as in the 30-second group, the more time they had to learn to fail.

These subjects had not been instructed to make visual images of words and their definitions during initial learning. Had that been done, there might have been fewer TOTs the second time and those that did occur could probably have been resolved by thinking of the cues.

So, the next time you have a TOT for somebody's name or some fact, first think of all the cues you can. If cues don't come to mind, you probably should quickly move on mentally to something else and periodically come back to the item that caused your TOT state. When the answer finally does come to you, make as many associations as you can that can serve as cues the next time.


Soucre: Warriner, A. B., and Humphreys, K. R. 2008. Learning to fail: recurring tip-of-the-tongue states. Quaterly J. Exp. Psychol. 61: 535-542.

Learning to Learn II – Learning Can Increase the Biological Capacity to Learn

I explained in my book on memory that the hippocampus is the brain structure that promotes consolidation of (declarative) short-term memories into long-term memories. I have also reviewed studies showing that the hippocampus is the one structure in the brain that clearly receives newborn nerve cells, even in the adult. New cells can enhance the ability of the hippocampus to create lasting memories. What has not been emphasized is the importance of survival of new neurons. To be of lasting benefit, new neurons must survive beyond just being born.

Insight into the requirements for neuron survival has come in a recent study by J. R. Epp and colleagues at the University of British Columbia. They injected rats with a chemical marker for DNA that shows up in any new DNA, that is in any newly born cells. If that marker shows up in a cell, it means that that this is a new cell that has incorporated the marker along with its new DNA.

Immediately after injection of the marker, the experimenters trained the rats in a large pool of water that had a safe platform located 2 cm under the water surface where rats could learn its location from seeing cues outside of the pool (such as windows, doors, pictures on the wall, etc.). Other studies had established that learning this task is accomplished by the hippocampus. Rats were divided into groups and trained on days 1-5, 6-10, or 11-15 after injection of the DNA marker. The new-DNA marker showed up only in rats trained on days 6-10 after marker injection. This indicated that there must have been new neurons in the hippocampus of these rats that did not survive in the two groups where marker was not seen. Put another way, for new neurons to survive there is a critical period where they have to be stimulated by learning experiences. Without that stimulus, they die.

Earlier studies had shown that new neurons in rat hippocampus have a development cycle wherein 6-10 days after birth is a middle stage of development in which new neurons are rapidly sending out membrane processes in search of contacts with other neurons. When neurons make contact with targets they can survive. The stimulus of learning thus provides a stimulus for forming new synapses with other neurons, thus enabling new neurons to survive.

The data were originally pooled across all rats in each test group. However, when the data were segregated by how well rats learned (the top and bottom 50 %), it became clear that it was only the poor learners that were showing an effect on new-neuron survival by maze learning. Poor learners probably got more stimulation from the learning because their brains had to work harder at it. It wasn’t that much of a mental challenge for good learners.

We know that humans are continually producing new neurons in the hippocampus. The issue is the need to experience enough demanding learning to help these new neurons survive. The critical period for learning to influence new-neuron survival in humans is not known. So, the practical take-home message is that we need to be learning constantly, every day, so that no matter what the critical period is, we will be helping our new neurons to survive. Survival of new neurons means a greater biological capacity for learning, at least in people who are not good learners. In other words, here is a clear case where the “poor get richer.”

Source: Epp, J. D., Spritzer, M. D., and Gales, L. A. M. 2007. Hippocampus-dependent learning promotes survival of new neurons in the dentate gyrus at a specific time during cell maturation. Behavioural Neuroscience. 149: 273-285.

Learn One Movement Skill At a Time

"Motor memory" refers to a mental model (MM) that the brain constructs from past experience. In the example given by researchers Reza Shadmehr and Thomas Brashara-Krug, when a person plans to pick up a brick, a MM of the amount of force required to pick up the brick is used to execute the action.The brain does not estimate the force as if it were a feather nor if it were a sack of cement, rather it uses its memory of what a brick weighs to create a model of how much force will be needed to pick it up.

In the studies they reported, they used a robotic arm that subjects used to manipulate objects. In learning how to use the mechanical arm, subjects had to create a MM of how to make it do what they wanted. Like other kinds of learning, the MM is consolidated with practice into long-term memory.Moreover, motor performance continues to improve, even after actual practice has stopped, indicating that the MM itself may be subconsciously rehearsed, off-line so to speak.

Motor memory processes have great applicability in everything from learning to touch-type to learning to throw a football to a moving target. The study by Shadmehr and Brashara-Krug explored the finding that a recently acquired MM (MM1) can be disrupted if a second MM (MM2) was introduced too soon after MM1.That is, a MM1 has to have enough time to consolidate, just as declarative memories do.

Also, a MM1 can interfere with learning a MM2, if there is not enough time separation between learning the two motor tasks.This was demonstrated in the present study by having 60 subjects learn how to make two conflicting movements using the robotic arm. The MM for both tasks could be learned but only if the training sessions were separated by at least 5 hours. If the interval was shorter, learning of the second MM (MM2) was impaired, as was the likelihood of consolidating the first MM.

The “take home message” of this research is that learning different movement tasks should be separated in time, lest there be interference with forming long-term memory of both tasks. My explanation is the following: Once MM1 gets consolidated (that is, after about 5 hours), the circuits that sustain its short-term representation now become available for learning a second motor memory (MM2). That is, MM1 has proactive interfering after-effects that dissipate with consolidation of the MM1 and thus no longer interfere with learning an MM2.

Athletic coaches might be well advised to ponder the application of this principle.


Shadmehr, R., and Brfashers-Krug, T. 1997. Functional stages in the formation of human long-term motor memory. J. Neuroscience. 17(1): 409-419.

Tests Produce Learning

Tests do more than just measure learning. Tests are learning events. That is, testing forces retrieval of incompletely learned material and that very act of retrieval helps to make the learning more permanent. Testing, and not actual studying, is the key factor on whether or not learning is consolidated into longer term memory.

A recent experiment by J. D.Karpicke and H. L. Roediger at Washington University in St. Louis, examined the role that retrieval had on the ability to recall that same material after a delay of a week. In the experiment, college students were to learn a list of 40 foreign language vocabulary word pairs, which were manipulated so that the pairs either remained in the list (were repeatedly studied) or were dropped from the list once they were recalled. It is like studying flash cards: one way is to keep studying all the cards over and over again; the other way is to drop out a card from the stack every time you correctly recalled what was on the other side of the card. In the experiment, after a fixed period of study time, students were tested over either the entire list or a partial list of only the pairs that had not been dropped. Four study and test periods alternated back-to-back. Students were also asked to predict how many pairs they would be able to remember a week later, and their predictions were compared with actual results on a final test a week later.

The initial learning took about 3-4 trials to master the list, and was not significantly affected by the strategy used (rehearsing the entire list or dropping items out as they were recalled). On average, the students predicted that they would be able to remember about half of the list on a test that was to be given a week later. However, actual recall a week later varied considerably depending on learning conditions. On the final test, students remembered about 80% of the word pairs if they had been tested on all the word pairs, no matter whether they had been studied multiple times with all of them in the list or if they dropped correctly recalled words from the list in later study trials. However, recall was only about 30% correct when correctly identified words were dropped from subsequent tests, even though all words were studied repeatedly. In other words, it was the repeated testing, not the studying, that was the key factor in successful longer-term memory.

So, what is the practical application? When using flash cards, for example, you need to follow each study session (whether or not you drop cards from the stack because you know them), with a formal test over all the cards. Then, repeat the process several times, with study and test epochs back-to-back. Can we extend this principle of frequent testing to other kinds of learning strategies? Probably. But there are no formal experiments.

Let us speculate on the case of trying to remember names of people at a party. You might study the name of each person by using it in conversation or associating the name with some feature of the person's anatomy or personality. Then, silently quiz yourself, looking at the person and asking yourself to recall the person's name. Then, repeat the study-and-test process several times. You would have to keep number of people low (say four to six), because you may not have many opportunities to hear the name repeated other than your own repeating it in conversation. In most practical learning situations, you will not be given repeat tests immediately after each study session, so you must simulate that with self-tests.

Why does forced recall, as during testing, promote consolidation? It probably relates to other recent discoveries showing that each time something is recalled the memory is re-consolidated. If the same information is consolidated again and again, the memory is presumably reinforced.

The failure of students to predict how well they would remember is consistent with my 40 years experience as a professor. Students are frequently surprised to discover after an examination that they did not know the material as well as they thought they did. Tests not only reveal what you know and don't know, they serve to increase how much you eventually learn. If I were still teaching, I would give more tests. And I would encourage students to use self-testing as a routine learning strategy, something that one study revealed to be a seldom-used strategy. The repeated self-tests should include all the study material and not drop out the material that the student thinks is already mastered.

Source: Karpicke, Jeffrey D., and Roedinger, Henry L. III. 2008. The critical importance of retrieval for learning. Science. 319: 966-968.

Overtraining: You Can Learn Too Much

Naps may be helpful for learning tasks other than those involving movement (see earlier note on work by Korman et al.).* An early study on the effects of napping had developed a useful texture discrimination task in which a visual display of horizontal bars has superimposed on it a brief display of three diagonal bars, followed by a blank screen, and then by a mask. The interval between the target and the mask is varied and the interval needed to achieve 80% correct responses is used as a measure of perceptual ability and working memory.

After a single training session, performance on this task improves only after subjects have had a normal night's sleep after the day's training. To be effective, a normal amount of dream sleep, which occurs mostly in early morning, is needed.

In a follow up study by another investigator, subject performance unexpectedly deteriorated if they were given 60-minute training sessions four times at regular intervals on the same day. In other words, the more the subjects were trained, the poorer they performed. However, this interference did not occur if subjects were allowed to nap for 30-60 minutes between the second and third sessions.

It is hard to explain why over-training disrupts performance, but one has to suspect that as training trials are repeated the information starts to interfere with memory consolidation, perhaps because of boredom or fatigue in the neural circuits that mediate the learning. Napping must have a restorative function that compensates for the negative effects of overtraining. What all this suggests to me is that memory consolidation would be optimized if learning occurred in short sessions that are repeated but only with intervening naps and on different days with regular night-time sleep. In other words, repeating long study periods in the same day on the same task can be counter-productive. This is yet another reason why students should not cram-study for exams. Learning should be optimized by rehearsing the same learning material on separate days where normal sleep occurred each night.

See my book on what science reveals about improving everyday memory. I also give seminars and workshops.

Sources:

Maquet, P. et al. 2002. Be caught napping: you're doing more than resting your eyes.Nature Neuroscience. 5 (7); 618-619.

Mednick, Sara, et al. 2002. The restorative effect of naps on perceptual deterioration.Nature Neuroscience. 5 (7): 677-681.

Improve Reading Efficiency and Comprehension

Reading To Remember

Get the mechanics right

○ Make eye contact with all the text not being deliberately skimmed
○ See multiple words in each eye fixation
○ Strive to expand the width of each eye fixation (on an 8.5" width, strive
for three fixations or less per line)
○ Snap eyes from one fixation point to another (horizontal snaps on long
lines, vertical snap if whole line can be seen with one fixation)
○ Get formal training from a reading center if needed

Strategy

○ Know what you are looking for. Identify the material that satisfies the purpose for which you are reading.
○ Skim the reading material first

• primes the memory
  
• orients the thinking
  
• think about the headings: they identify what can be skimmed rapidly, what needs more thoughtful reading
  

Tactics

○ Read with a purpose.
○ THINK about what you read. The more you think about it, the more you will remember. Ask yourself questions about what you read, as you are reading and afterward.

• Is it satisfying your purpose?
  
• How does it relate to what you already know? ... and need to know?
  
• What is not said that should be?
  
• What is said that you think is wrong or needs elaboration?
  
• What do you not understand?
  
• What needs special effort to remember?
  
• How can you use this understanding and information?
  

○ Pause and rehearse (after every minute or so, for example)
○ For each new reading segment, ask “How does this build on what I just read?”
○ Reading sessions should be limited (15 to 30 minutes)
○ At the session end, rehearse what you learned - right away, without distractions. Answer again the questions mentioned above.
○ Think about and rehearse what you read at least twice later that day.
○ Rehearse again at least once for the next 2-3 days.