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Limitations of Brain Imaging Research for Reading Instruction · The Reading Instruction Show

• 0:00
  This is the Reading Instruction Show. As always,
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  I'm your host, the genial one, Dr. Andy Johnson.
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  Topic of today's podcast, limitations of brain
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  imaging research for reading instruction. Now,
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  just because a book, article, or presentation
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  includes fancy pictures of a brain or uses a
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  whole bunch of big brain words does not meaning
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  the information presented is always accurate
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  or scientific. We must be responsible consumers
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  of all information and this includes brain imaging
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  research for reading instruction. So the basics.
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  The first thing to understand is that brain imaging
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  is not a single uniform thing. They're different
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  types of brain imaging technologies that measure
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  different things in different ways. These include
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  the following, computed, computed tomography,
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  magnetic resonance imaging, magnetic osemp -
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  something or other, positron emissions tomography,
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  single - Okay, I don't need to go through all
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  those names. You can read it yourself if you
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  read the article. But, When I say measure, all
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  these different technologies identify which parts
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  of a person's brain becomes active under certain
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  conditions. And these different technologies
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  record, measure, or track the following kinds
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  of things. Magnetic field and radio waves. Changes
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  in blood flow and oxygen levels. electrical activity,
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  movement of water molecules, a mildly radioactive
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  substance called a tracer as it moves through
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  the brain, and a series of x -rays. Different
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  types of things are measured or tracked. Now
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  there are two big takeaways here. First, brain
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  imaging research is not a single uniform thing.
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  And second, different technologies measure different
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  things in different ways. Now let's look at methodological
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  concerns. I'm just an old literacy professor,
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  not a neuroscientist. However, you don't have
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  to be a neuroscientist to see some of the common
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  methodological concerns. And I'm going to outline
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  these for you. You're welcome. Not all brain
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  imaging research studies related to reading instruction
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  have all these methodological concerns. However,
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  you'd be hard -pressed to find a study that's
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  not impacted by at least some of these 15 methodological
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  concerns that I am going to present unto you.
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  Number one, small sample sizes. The limitation
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  identified most often in brain imaging research
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  is related to a small sample size. Because of
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  the type of technology involved, researchers
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  are limited to studying one person's brain at
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  a time. As a result, many brain imaging studies
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  include only 10 to 20 people. Two inauthentic
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  tasks What subjects are asked to do in many brain
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  imaging studies is not reading. Instead, they're
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  asked to identify letters, letter sounds, individual
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  words, and non -words. The cognitive processes
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  used to do these things, these non -reading things,
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  are much different from those used to create
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  meaning. Three, false assumptions. Research based
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  on false assumptions yield fallacious results.
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  Many brain imaging studies are often based on
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  the false assumption that A, reading is sounding
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  out words, B, readers must convert writing language
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  into oral form and listen in their head, or C,
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  low -level reading subskills are key to reading.
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  And simply saying something is key to reading
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  or an essential component of reading doesn't
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  make it so. The research -based evidence to support
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  any of these three assumptions is weak. Four,
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  big words and images. People are much more likely
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  to accept new information as being accurate.
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  or to rate articles and presentations as having
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  scientific evidence for something if it includes
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  a picture of a brain image. And I cite a study
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  by Bishop 2013 here. This leads to the false
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  assumption and neuromyths that are left unchallenged
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  by the popular media. 5. Expertise in reading
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  Neuroscientists are not experts in reading. As
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  such, they often don't understand reading behaviors
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  or processes. Also, they often ask the wrong
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  questions, collect the wrong kinds of data, or
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  make certain creative interpretations of data
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  they've collected. Six, simulated environment.
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  Brain imaging research occurs in a laboratory
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  setting, not a classroom. The interpretation
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  of the results often does not account for this
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  in authentic context. 7. Cognitive and emotional
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  state. We think and we emote with the same brain.
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  As such, brain imaging is impacted by the emotional
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  state of the individual as well as the differing
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  cognitive tasks they're asked to perform. 8.
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  Correlational. Findings are often correlational,
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  not causal. They tell us nothing about the cause
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  of reading difficulties or what conditions might
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  lead to improved reading performance. Nine, transfer.
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  Neuroscience does not tell us what works in the
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  classroom. The results, while important, do not
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  transfer to classroom applications. In other
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  words, you can't say that Method A was effective
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  or Method A was more effective than Method B
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  based on neuroimaging research. Ten, reliability.
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  Concerns have been identified as to the reliability
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  of brain imaging research. Reliability is the
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  basis of scientific knowledge. This means that
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  an instrument or measure will produce similar
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  or reliable results if repeated with the same
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  person. Reliability is also related to replicability.
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  This means that replicating The experiment with
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  a similar population will produce similar results.
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  11. Picking cherries. The findings of some brain
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  imaging research studies were found to be impacted
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  by incompletely reporting the data or by rejecting
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  outliers. That is cherry picking. 12. Confirmation
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  bias. Confirmation bias has been noted in some
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  brain imaging research studies. And this occurs
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  when researchers begin with strong beliefs and
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  see only data that confirms their pre -existing
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  beliefs. In other words, they see what they're
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  looking for and don't see what they're not looking
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  for. Thirteen inconsistencies. There have been
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  inconsistent findings between studies. This may
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  be a result of different technologies that are
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  used to measure different things as well as small
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  sample sizes and different tasks asked of subjects.
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  Fourteen, I see this a lot. Because of the small
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  sample sizes, many brain imaging studies try
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  to make comparisons between dissimilar control
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  and experimental groups. Using similar groups
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  is necessary to make valid comparisons of any
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  kind. And 15, the single study. You cannot extrapolate
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  results based on a single study of anything.
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  One study is not the research. One study does
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  not prove or debunk anything. One study simply
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  takes a close look at one question at a specific
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  group doing a specific thing in a specific place.
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  So conclusions, I don't want to imply here that
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  all brain imaging research related to reading
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  instruction is flawed or there's nothing to learn
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  from it. Quite the opposite. Brain imaging research
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  has contributed greatly. to the field of literacy
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  instruction. However, we must be aware of the
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  overinterpretation and misapplication of brain
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  imaging research, as well as its limitations
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  in informing classroom practice. Brain imaging
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  research provides important information about
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  how things work, but not what things work. To
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  determine what works for reading instruction,
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  applied research conducted in classroom settings
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  related to instructional methods, strategies,
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  and techniques is necessary. And of course, what
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  works is not a universal variable. What works
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  for some students and some settings for some
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  purposes does not work for all. This has been
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  The Reading Instruction Show. I am your host,
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  Dr. Andy Johnson.