Which Brain Research Can Educators Trust?

Abstract

Neurological research has discovered much about how the brain works, Dr. Willis writes. But educators need to be cautious when applying this research to teaching. ********** IN 1681 Thomas Willis coined the term And 300 years later I began my practice of child and adult neurology. When I subsequently moved into teaching, I found that the tools of neuroimaging, which show the brain actively processing information, helped me make connections between classroom strategies and neuroscience. Let me begin with a brief explanation of the three most important technological advances in brain research: Positron Emission Tomography (PET), Functional Magnetic Resonance Imaging (fMRI), and Quantitative Encephalography (qEEG). PET relies on the fact that the brain is extremely hungry for glucose and oxygen. PET scans measure the burning of glucose in the brain. In this technique, positron-emitting isotopes, which function as radioactive tracers, are injected into the arteries in combination with glucose. The rate at which specific regions of the brain metabolize the glucose is recorded while the subject is engaged in various sorts of cognitive activities. These recordings are then used to produce maps of areas of high brain activity during particular cognitive functions. A similar technology is employed in fMRI. However, fMRI takes advantage of a special property of hemoglobin, a blood protein that brings oxygen to body tissues. Hemoglobin that is carrying oxygen differs from hemoglobin that is not carrying oxygen. Active regions of the brain receive more blood and thus more oxygen than less-active regions. By detecting oxygen-containing hemoglobin, scientists use fMRI to assess changes in blood flow, and thereby metabolic activity, in specific areas of the brain while subjects are engaged in various activities. Finally, qEEG or brainwave monitoring provides brain-mapping data that are based on the very precise localization of brainwave patterns coming from the parts of the brain that are actively engaged in the processing of information. Through digital technology, qEEG records electrical patterns at the surface of the scalp that represent cortical electrical activity or brainwaves; qEEG recording as it is used in learning research measures the brain's responses to reading, listening, math, or other learning and thinking activities and provides visual summaries in topographic maps. Only in the past 20 years, with the ability to track the neural circuits that enable us to think and learn, have cognitive neuroscientists been able to study how our brain structures support our mental functions. Today, research in learning, thinking, and remembering is being conducted more and more at the level of neural circuits, synapses, and neurotransmitters, and the time for mind-blowing advances in classroom teaching strategies is at hand. Brain-based research in learning has given educational researchers the means to translate neuroimaging data into classroom strategies that are designed to stimulate parts of the brain seen to be metabolically activated during the stages of information processing, memory, and recall. And what has emerged from the neuroscience of learning over the past two decades is a body of highly suggestive evidence that successful strategies teach for meaning and understanding, that learning-conducive classrooms are low in threat and high in reasonable challenge, and that students who are actively engaged and motivated devote more brain activity (as measured by metabolic processes) to learning. BRAIN-BASED RESEARCH--A WARNING LABEL Good-quality, peer-reviewed brain research can provide solid biological data and explanations, but educators need to be cautious about the claims that are said to be based on brain research. Not all of them are valid. Subsequent reevaluation of some early research interpreting PET scans has given us reason to be careful about which research we judge to be valid enough to connect with actual learning. …