Monday, January 31, 2011

Omega-3 deficiency and low dietary omega-3 to omega-6 ratio may exacerbate depression and reduce neuroplasticity

Here's an interesting update on the dietary fatty acid issue, as it pertains to mood disorders and neuroplasticity:
http://www.nature.com/neuro/journal/vaop/ncurrent/full/nn.2736.html

This article, published in Nature Neuroscience (January 30, 2011), is an example of some good research being done by a group at the University of Bordeaux in France.  They demonstrate substantial negative neurophysiological changes in mice as a result of an omega-3 deficient diet.  It is interesting to note that the brain's endocanniboid system is specifically affected by omega-3 deficiency, according to this research.

This is further evidence supporting the importance of attending to a healthy diet, in maintaining optimal mental health.  Omega-3 fatty acids are one element of a healthy diet.  While omega-6 fatty acids are also needed in the diet, these lipids behave to some degree competitively with omega-3.  Therefore,  the ratio of dietary omega-3 to omega-6 is is very important.  Western diets tend to have an unhealthy ratio of these lipids, due to excessive omega-6. 

An ongoing issue of debate has to do with whether plant sources of omega-3 (primarily ALA) are as useful as fish sources (DHA and EPA).  Existing evidence shows that DHA and EPA are more important.  ALA can be converted in the body to DHA and EPA, but the efficiency of this may vary from person to person.

Wikipedia has a nice review of this subject: http://en.wikipedia.org/wiki/Omega-3_fatty_acid
but some of the sources are less than ideal.

It is interesting to consider that the DHA/EPA issue is not a "micronutrient" issue.  They could be considered  "macronutrients."  The solid mass of the brain consists mostly of lipids (60-80 % of the non-aqueous mass); DHA and EPA  make up over 10% of this lipid mass, which is a very high concentration.


Here's a link to a paper which quantifies the  high fractions of omega-3 lipids in brain mass:
http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=921064   --this paper also showed that dietary changes substantially altered the proportion of omega-3 lipids in brain tissue

Monday, January 24, 2011

"Outlier": The causes of high achievement

Outlier by Malcolm Gladwell, is a brilliant book about the causes of success, outstanding achievement, and personal greatness.

Gladwell describes a variety of interesting life stories, of people with outstanding ability or outstanding achievement, then looks carefully at the factors leading to these successes.

He does not claim that "inborn traits" or hereditary factors are unimportant.  But he shows quite convincingly that inborn talents correlate with achievement only to a certain point.  Individuals with extreme talents tend not to achieve more than those with merely "sufficient" talents. A recurring theme in this book, shown through one example after the next, is that the simple stories many people might have, to account for a person's great achievements, are often appealing and believable, but are in fact often inaccurate or at the very least incomplete.

He shows that various situational biases can have a profound, snowballing effect on the course of successfulness in a person's life.  A trite detail such as birthdate can lead to a cascade of advantages or disadvantages for athletes, which then accumulate over many years (his example is of successful hockey players being much more likely to have an early birthday--if you're born in December, this is an instant disadvantage, as you will be a little bit smaller and weaker on average compared to your teammates, therefore the older players will tend to outperform you, leading to a smaller chance of  you being noticed or advanced to a more challenging team, or to be deemed "gifted" and given more ice time, etc.)  

He emphasizes the role of thousands of hours of intensive practice being required to master a skill.  Those who have 10 000 hours of practice under their belt early on in their lives--particularly if some serendipitous quirk of fortune allowed them to be one of the only individuals, or one of the first, to gain this experience-- have a strong chance of succeeding spectacularly in their fields.  He gives examples such as Bill Gates, or the Beatles, or some of the most successful New York lawyers doing a particular type of law. 

One of the psychologists cited in this book,  who has studied the area of "exceptional achievement" is AK Ericsson, who generally argues that "extended, intense practice"  is the primary determinant of elite performance, as opposed to inborn talent.  The ability to do this type of practice, of course, requires or is greatly facilitated by, motivational resources as well as environmental opportunity, parental support, a culture which favours such as endeavour, etc.) Here are some references to articles of his:
http://www.ncbi.nlm.nih.gov/pubmed/17905932
http://www.ncbi.nlm.nih.gov/pubmed/17642130
I suspect that heredity is quite relevant, but may manifest itself in many ways aside from what many people might assume.  Factors that could be considered at first glance to be a disadvantage, either hereditarily or environmentally, may, in the world of successfulness, end up being compelling advantages.

Guillermo Campitelli is another excellent researcher in this field; here's a reference to one of his recent papers: http://www.ncbi.nlm.nih.gov/pubmed/17201516.  The evidence here, looking specifically at chess players as a model of acquiring expertise, affirms the extreme importance of thousands of hours of  practice, but also recognizes that some players improve much more than others with the same amount of practice.  This is probably the influence of inherited talent.  Maybe there could be other hidden variables, including family or cultural factors.   He suggests that the age at which the practice begins is another important variable.  

It should be noted that, in this literature, "deliberate practice" refers to a type of activity which is specifically directed towards performance improvement, is adequately difficult, has feedback about performance, and which has opportunity to correct errors.  This differs from "ordinary" work experience, which may be quite a bit less intense and much less geared towards improving skills.  I suspect that the quality of "deliberate practice" may vary quite a bit, depending on the degree of immersion, concentration, energy, engagement, and meaningfulness there is in the action.  I wonder if enjoyment of the practice is a major variable too, I would be interested to see if some of these researchers would look at this.  If someone finds their 100 hours of practice meaningful and enjoyable, I have to wonder if they might advance much more than someone whose 100 hours were a drudgery.    

Another excellent angle of discussion in Gladwell's book has to do with understanding a person's cultural background and childhood developmental history, as extremely important determinants of success.   This leads to discussions about opportunity, pedagogical technique and policy, etc.  Sometimes cultural or developmental factors cause individuals to lack a certain skill necessary to succeed, or put individuals at risk of recurrent severe problems or frustrations.  Good examples are given, including the story of a profoundly gifted intellect who was never able to share his talents; and of highly trained pilots who were too quietly respectful of authority to be able to proactively use strong assertive social skills to prevent an aviation disaster.

I'll add to this post later on, to expand some thoughts about achievement and success.  In the meantime, I think Outlier is a worthwhile and entertaining read.

Friday, January 21, 2011

Writing about worries can ease exam anxiety

Here's another simple research finding, published recently in Science by Sian Beilock:  students who spent ten minutes--immediately before a test--writing down their thoughts about what was causing them fear, performed substantially better on the test.


http://www.ncbi.nlm.nih.gov/pubmed/21233387


I'll have to review this paper in more detail to comment further, but I think it is another simple anxiety-management tactic for exam or performance preparation.  A frantic review or a frantic bout of anxious rumination right before an exam is unlikely to help -- an anxiety-management exercise such as expressive writing is very much more likely to help, and a study like this is strong evidence of this.

The article shows that the effective action was specifically to write about negative thoughts and feelings during the ten minutes before the beginning of a stressful exam.  A control activity--of writing about anything that comes to mind--was not effective.   So the effectiveness of this technique was not simply due to distraction. 

I would be interested to see the authors' opinions and/or research about whether specific journaling techniques could work particularly well, or less well, in various anxiety scenarios.  Sometimes, purely "negative" journaling can end up being a somewhat ruminative activity which entrenches negative emotional states and attitudes (e.g. one can get worked up in a cynical, pessimistic rant, which could increase or magnify one's following cynicism or pessimism, or increase one's filtered attention to negative events in the day).
See the following references:
http://www.ncbi.nlm.nih.gov/pubmed/12173682 
http://www.ncbi.nlm.nih.gov/pubmed/17120515
   A "balanced" journaling style, which includes room for free discussion of thoughts and feelings, but also room for positively-focused or constructive discussion may prevent this risk of snowballing rumination or negativity from a journaling activity.   One simple aspect of this experiment was that the journaling was immediately before a performance, and was very time-limited (10 minutes); these factors may reduce the potential for the journaling to be a negative or ruminative behaviour, and may increase the chance of the activity serving to process anxious emotion effectively.

Testing improves learning

Here's another recent bit of research, published in Science, demonstrating the value of doing a test ("retrieval practice"), immediately after learning something.  Those who did the tests, instead of other study techniques, had much better retention 1 week after learning something.

http://www.sciencemag.org/content/early/2011/01/19/science.1199327.abstract
This finding is consistent with my believe that a lot of study time is inefficient, because it encourages the studier to push forward to "get more reading done", before the reading which was just done has been consolidated well or reviewed.  Even though "pushing forward" may seemingly cover more pages of text, it accomplishes less long-term learning.  A much more efficient use of time is to pause, review, and do a test on the material at just the right interval.  If the interval is too short, the tests will be too easy, and the review will also be an inefficient use of time.  If the interval is too long, too much will have been forgotten already, the tests will be too hard, and it will make you have to go over the same material again, another inefficiency.

I don't believe findings such as this one necessarily contradict ideas about  flexible or "constructivist" approaches to education.  Nor do I believe it has anything to do with the controversial area of standardized tests for children or professional schools, etc.  Standardized tests are not a mechanism for education, they are assessment tools (how good they are as assessment tools would be a subject for a good debate).

There are some instances in which pausing frequently to review could disrupt a larger thematic appreciation of a subject or experience--it would be like pausing a movie every ten minutes to answer questions about the plot or characters--so, of course, sometimes this technique would have to be set aside.

I think that flexible, personalized educational approaches are extremely important--but this evidence about the merits of retrieval practice testing can be applied to any such style.  Its immediate value is in helping people use their time more efficiently for many study tasks.

A previous post also deals with the subject of study efficiency, and actually cites a more densely technical analysis showing more or less the same result, though it adds information about the frequency with which one should optimally pause to test oneself: http://garthkroeker.blogspot.com/2010/04/optimal-learning-training-schedules.html

Monday, January 10, 2011

Reading Exercises

A common problem I find among university students is difficulty reading quickly or efficiently.  Reading problems can also occur in conjunction with depression.

The best thing to do to improve reading skills is, of course, to read more.  But a phenomenon which often happens when reading any text, but especially longer texts, such as novels, is that you can lose track of what you have just been reading.  Whole sections of the text may end up being skimmed superficially, as part of your attention lapses or wanders, while still maintaining a basic pace of absent-minded reading.  This leads to a lack of enjoyment or feeling of mastery with reading, dampened morale, sapped motivation, contributing further to any depression which had been present, and deterring further reading efforts. 

An approach to this type of problem requires you to stop to reflect or answer questions frequently about what you have just read.  Whenever you test yourself regularly, your learning and retention are greatly increased.  Most good introductory university textbooks are set up this way.  But not very much in the line of non-textbook reading.  

So, I have been trying to find resources to help with reading skill, for adults.  Elementary-school language textbooks or readers seemed like a reasonable thing to check.   I certainly recommend that adults at least periodically read books which have been written for children or adolescents.  The best things I've found online are from ESL (English as a second language) programs.  Even if you are an advanced reader, or have spoken English all your life, I think that ESL exercises could be good for improving reading skill. 

Cognitive-skills training websites tend not to offer very much in terms of language learning or improving reading fluency or retention.  I wish that the cognitive skills website people could develop more along these lines: reading-oriented games don't seem very difficult to imagine or design, compared to other types of games.

Here's a list of a few sites I've found, where you can practice English reading skills:

http://web2.uvcs.uvic.ca/courses/elc/studyzone/
This is an excellent free resource from the University of Victoria (in BC).  For the reading exercises, choose an "English language level"  (beginner to advanced), then follow the links about reading. 

Houghton Mifflin College
This site also offers timed readings with questions afterwards. 


Quizzes Based On VOA Programs (ESL/EFL)

This link goes to a site where you have to read a text a sentence at a time, and fill in the blanks from a list of options, according to what makes sense or is grammatically correct.  While some might find this type of exercise too easy, I think it is a nice way to remain more interactive with the text.  If you do find it easy, you can just try to do it faster, and make it into a game. 

Another useful thing to look for is an online book club which has discussion questions about the book you're reading.  Some sites have questions for each chapter, which is the type of thing I'm recommending, so that you can pause frequently to review what you have just been reading.   I haven't found a single site which has chapter-by-chapter questions for a wide variety of books, but here's an example of a specific site, giving questions about Great Expectations by Charles Dickens (a great book, by the way):
http://www.victorianweb.org/authors/dickens/ge/pva107.html