Friday, October 31, 2014

Distinguishing between data & interpretation in popular science can help the public learn to think about the evidence (Books - The Organized Mind by Daniel J. Levitin)

Nowadays, the outcome of every scientific study is expected to be instantly useable by the public.  News media demands ready-made dietary and medical advice, politicians and business people demand data to shore up the opinions they already hold, many funders want only outcomes that will translate to curing disease now.  As nice as it would be to cure on demand, that would be as likely as making a hits of every Broadway tryout.  Scientific "hits" are the product of fortuitous accident and incremental accumulation of knowledge, which usually includes more rejected possibilities than confirmed ones.

Pop-neuroscience satisfies this expectation with books falling somewhere between science and self-help.  Daniel J. Levitin's The Organized Mind (Dutton, 2014) creatively hews to this formula. I thank Dutton, a Penguin imprint, for my copy.  Of course the popularity of science, is not all bad.  It is wonderful to have the ear of non-scientists and encouraging that interest requires that the public enter the discussion somewhere.  But books that realistically convey how experimental outcomes find their way into the fund of general knowledge are in short supply.  The wider the dissemination of half-baked knowledge, the more discerning the eager-to-consume non-scientist must become.  In this age in which everything from raw experimental data and top notch interpretation to crackpot appropriation of small study outcomes and outright lies are easily available on line, and look superficially the same, the scientist has a responsibility to help the public develop a critical eye.

Dr. Levitin, a former musician and producer turned scientist, can be an effective ambassador for neuroscience.  His book rests on the foundation that we live under conditions of information overload.  Our brains are not thought to be limited in how much information they can store, but there is a limit to how much we can pay attention to at any one time, limiting what gets in (encoded), and how much we can successfully re-access once it is learned (retrieve).  Writing, Levitin tells us, is the cultural tool that greatly enhanced our capacity to store information.
Once memories became externalized with written language, the writer's brain and attentional system were freed up to focus on something else.  But immediately with those first written words came the problems of storage, indexing, and accessing:  Where should the writing be stored so that it (and the information it contains) won't get lost? ... Later we developed other mechanisms - such as calendars, filing cabinets, computers, and smartphones - to help us organize and store the information we've written down...We are off-loading a great deal of the processing that our neurons would normally do to an external device that then becomes an extension of our own brains, a neural enhancer.
So when we don't need the information, human brains have evolved to solve a big problem, but when retrieval is desired, we have essentially traded the problem of remembering the information for the problem of remembering where we put it.  The brain's storage system is associative, that is, information is filed with other information related to it.  These relationships can be semantic (meaning related), driven by perceptual factors (a red thing is stored with other red things), use-based (a kitchen utensil with other kitchen things), or episodic (remembering what I wore at the party may be triggered by remembering other things associated with that particular place and time).  Associative structures are thought of as networks.  Any point (node) in a network (a bit of knowledge) is connected to many other points.  This has the advantage of allowing multiple routes to access any bit of information.  Things learned together are more quickly retrieved together.  So multiple nodes related to cooking (spoons, onions, potholders) will be activated when I'm in the kitchen, "readying" access to such information.  If a neuroscientist appeared in our kitchen, testing our ability to remember words, we would more quickly access the word "spoon" than the word "violin."  If we were retrieving the word "pot," we would more quickly access its cooking-related meaning that its meaning as a colloquialism for marijuana.  Triggering multiple nodes when trying to access just one also had a disadvantage, in that competing information can rise to awareness, distorting memories, triggering unexplained feelings (time for a trip to the therapist), or creating a bottleneck, leaving us unable to remember what we want at all.  Of course this never happens to me.

Since cognitive overload is a given, Levitin tells us, his book is a primer in how the brain has evolved to get information in and out, what can go wrong, organizing strategies used by both brains and human beings (an important distinction that Levitin is not always careful to make), and what a poor overloaded person can do to minimize breakdowns.

As if by example, he divides his topic into sections, using categorization as he organizing strategy.
We treat things as being of a kind so that we don't have to waste valuable neural processing cycles on details that are irrelevant for our purposes.  When looking out at the beach, we don't typically notice individual grains of sand, we see a collective, and one grain of sand becomes grouped with all others.  It doesn't mean that we're incapable of discerning differences among the individual grains, only that for most practical purposes our brains automatically group like objects together.
Levitin focuses on organization within the home, social, and business worlds - a scheme which organizes the practical advice he delivers while reframing discussions of well-trodden cognitive science topics such as cognitive biases.  These behavioral processes unconsciously distort perception or judgment, resulting in outcomes that would counter what factual knowledge or statistical accuracy would suggest is true.  Confirmation bias - the tendency of people to interpret information in a way that confirms the ideas they already have, is one example.  Levitin interprets bias less as faulty decision making than as a byproduct of an organizing strategy employing socially relevant cues to mitigate information overload, backing up this claim with experimental evidence.

Levitin writes in an easy-to-understand style, with nearly up-to-the-minute references to Mad Men and the Egyptian revolution, and offering plenty of tangible behavioral examples.  In his introduction to information overload, he places us in the moment with the example of a Romanian student thrown into shock when she goes to a North American campus bookstore to purchase a pen and is faced with an entire aisle of them.
...unproductivity and loss of drive can result from decision overload.  Although most of us have no trouble ranking the importance of decisions if asked to do so, our brains don't automatically do this.  Ioana knew that keeping up with her coursework was more important than what pen to buy, but the mere situation of facing so many trivial decisions in daily life created neural fatigue, leaving no energy for the important decision.
Unfortunately, stuffed as this book is with appealing accounts of neuroscience findings, there are occasions of playing it fast and loose with the science.  Take the above example.  Overload may have made Ioana tired, but measures of neurons never came up at all.  Do cells even get tired?  Studies of human states and behaviors and studies of brain cell activity are not necessarily interchangeable.  Levitin told an effective story, but it was of a student's experience who was overwhelmed by choices, not of her brain, at least that was the information available.  I looked for footnotes.  There were none.  Flipping to the back of the book there were sources not enumerated in the text.  An article in a reputable social science journal, written by respected researchers was referenced, but their study measured behavior, not neural activity.  If neurons aren't measured then Levitin's assertion is an as yet to be tested guess.  It is not a shortcoming to make a guess in a book, it is exciting to follow a good scientist's interpretation of study outcomes, but then allow us to follow the thinking.  More careful writing and referencing would be needed if the reader was to distinguish between brain and behavior, between interpretation and study outcome, and this sort of book is precisely the medium where a general reader could be guided in understanding that distinction better.    

Compelling readers to search for unmarked references conveys the idea that consulting the source of knowledge is an inconvenience or embarrassment.  We are further informed that these notes are filtered, including only sources vital to "scientific" points because this is more "useful" for a general reader.  So, perhaps Levitin did read a study on fatigued neurons?  Surely that would be a scientific point.  How is this omission useful?  If one is willing to attract sales based on the appeal of science, then one should be willing to elucidate the work that makes that science reliable.  Evidence testing is what distinguishes science from other branches of knowledge.  Never has the gulf between evidence and intuition been so clearly highlighted as by the current discussions on policies for those who have been in contact with ebola patients but are not themselves infected.  How can we expect non-scientist citizens to make choices based on evidence if they never get any practice?  The popularity of science in books, television, radio, and other media is terrific, but it is only science if evidence testing and critical thinking shape the content.  If evidence is not important to writers and publishers of science, to whom should it be important?

Levitin occasionally uses a careless turn of phrase when a precise one would have been preferable.  When writing about attention, he refers to a "zenlike focus."  What is that?  Narrow?  Diffuse?  Sustained?  Relaxed?  I wouldn't care in a novel or a cultural article in The New Yorker, but in a neuroscientist's writing on attention, this sort of colloquial term lacks specificity because it is one for which everyone thinks they know the meaning, but for which, in fact, there are many meanings.   

Despite my serious criticisms of the contradictory standards practiced in the popular science genre, Levitin writes fluidly and engagingly.  He reaches out to a range of reader, writing of attentional filters with both vivid examples of Where's Waldo and the balance of neurotransmitters.  He offers salient examples of the categorization of objects using stereotypic reactions to insects but also writes about cortico-thalamic loops - neural circuits which participate in such processing: something for everyone.  At times, Levitin parsed data with precision that helped the general reader understand the significance of those outcomes in ways that may not otherwise have been obvious.
...The current online dating world shows at least one somewhat promising trend: so far, there is a 22% lover risk of marriages that began online ending in divorce.  But while that may sound impressive, the actual effect is tiny.  Meeting online reduces the overall risk of divorce from 7.7% to 6%.  If all the couples who met off-line met online instead, only 1 divorce for every 100 marriages would be prevented...
Such attention to detail contrasts the examples I gave earlier, and Levitin's writing did not suffer, so perhaps closer editing might have been helpful.  Finally, since this book was as much self-help as science, I should say that I found the organizational advice useful and that presenting it in the context of attention, memory, and executive function studies only added to my willingness to accept it and to my ability to retain it. Whether that is a function of my neuroscience background or whether it was experienced similarly by science tourists, I cannot say.  But we could conduct an experiment and collect some evidence to figure it out!


Sheila O'Malley said...

Your observations are fascinating! Thanks for putting in the time with this one.

// but in a neuroscientist's writing on attention, this sort of colloquial term lacks specificity because it is one for which everyone thinks they know the meaning, but for which, in fact, there are many meanings. //

That is extremely well-put and I try to keep that in mind with my own writing - but it is very helpful to hear you pull out examples.

Ted said...

S - Thanks for your thorough reading of this, it's good to bump up against a discerning reader!