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STUDI Course, August 2012. “Current brain research related to teaching & learning” Dana Merriman, Professor of Biology Teaching: Human Phys 212, Neurobio 306, Bio of Gender 310 Research: Retina & optic nerve response to injury.
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STUDI Course, August 2012 • “Current brain research related to teaching & learning” • Dana Merriman, Professor of Biology • Teaching: Human Phys 212, Neurobio 306, Bio of Gender 310 • Research: Retina & optic nerve response to injury
What does your speaker (an eyeball specialist) know about the neuroscience of learning? STUDI Course, August 2012 • Teach basic mechanisms (neuron structure/function + memory pathways) twice a year • Teach neuroscience each spring; learning unit included • Prepublication reviewer of “Cellular and molecular mechanisms underlying learning and memory impairments produced by cannabinoids” (Sullivan, 2000) • Taught BBE workshop at Christa McAuliffe Academy for K-12 teachers in 2005 2
Four selected neuroscience principles behind Brain-Based Education STUDI Course, August 2012 • 1. Brain structure & function are shaped by environment & experience, not just by genes. • “Epigenetics” is one mechanism for this. • 2. Brains are “plastic”, rather than “hard-wired”. They are “changing all the time”. Educational strategies can influence that change. • 3. When a brain learns, neurons synthesize new structures. • So long as they have accurate instructions (genes), the necessary building materials (nutrition), and sufficient energy (nutrition) to do so. • 4. Certain kinds of stress impair learning, as do certain drugs. 3
Four selected neuroscience principles behind Brain-Based Education STUDI Course, August 2012 • 1. Brain structure & function are shaped by environment & experience, not just by genes. • “Epigenetics” is one mechanism for this. • 2. Brains are “plastic”, rather than “hard-wired”. They are “changing all the time”. Educational strategies can influence that change. • 3. When a brain learns, neurons synthesize new structures. • So long as they have accurate instructions (genes), the necessary building materials (nutrition), and sufficient energy (nutrition) to do so. • 4. Certain kinds of stress impair learning, as do certain drugs. 4
COMMON MISCONCEPTIONS ABOUT PLASTICITY STUDI Course, August 2012 • Not new. • Plasticity demonstrated 1940s, mainstream 1970s. • Not global or profound. • Brain isn’t rebuilt from scratch each day. • Not consistent. • Some life stages are more plastic than others. • Some brain parts are more plastic than others. • Very likely there are inter-individual differences. 5
What IS plasticity? Just HOW do brains “change”? STUDI Course, August 2012 • Number of neurons (↑ via “neurogenesis”) • Number of synapses between neurons • Connection pattern of synapses between neurons 6
What IS plasticity? Just HOW do brains “change”? STUDI Course, August 2012 • Number of neurons (↑ through “neurogenesis”) • Number of synapses between neurons • Connection pattern of synapses between neurons • Strength of individual synapses between neurons 7
To SOME extent, cortical brain maps are plastic STUDI Course, August 2012 FINGERTIP TOUCH 8
STUDI Course, August 2012 FINGERTIP TOUCH SIGHTED PERSON VISION 9
STUDI Course, August 2012 FINGERTIP TOUCH BLIND PERSON TAUGHT BRAILLE FINGERTIP TOUCH 10
STUDI Course, August 2012 FINGERTIP TOUCH SIGHTED PERSON WHO, FOR A FEW DAYS, IS BLINDFOLDED AND TAUGHT BRAILLE… FINGERTIP TOUCH 11
STUDI Course, August 2012 FINGERTIP TOUCH …A FEW HOURS AFTER REMOVING BLINDFOLD VISION 12
Embryonic plasticity can compensate for profound brain volume deficiency STUDI Course, August 2012 2009 case study: A German girl was discovered at age 3 years to have been born with only one brain hemisphere. Now 10 years, she “has normal psychological function and is perfectly capable of living a normal and fulfilling life. She is witty, charming and intelligent.'" 13
IMPORTANCE OF CORTICAL PLASTICITYTO LEARNING STUDI Course, August 2012 • Gray matter “thinking cap” of neuron nuclei & synapses • Hippocampus (memory consolidation & short term storage) • Olfactory cortex (odor learning) • Neocortex; mammals only (sensation, perception, long term storage) • Sensory cortex: baseline sensation • Motor cortex: motor commands • Association cortex: perception/awareness, higher mentation, memory storage 14
(2008) Neuroplasticity: a fresh look at brain based education. http://www.fasa.net/upload_documents/NEUROPLASTICITY10.29.pdf STUDI Course, August 2012 • 1. The human brain can and does grow new neurons. • Many survive and become functional. We now know • that new neurons are highly correlated with memory, • mood, and learning. Of interest to educators is that this • process can be regulated by our everyday behaviors. • Specifically, it can be enhanced by exercise, lower levels • of stress, and good nutrition. Schools can and should • influence these variables. This discovery came straight • from neuroscientists GerdKempermann and Fred • Gage.6 15
After birth and throughout life, the brain grows new neurons. STUDI Course, August 2012 • Demonstrated in rodents & birds in 1962, 1977, 1983. • Olfactory cortex (SVZ); related to odor learning? • Hippocampus (SGZ); related to other learning? • Disregarded for years because not found in monkeys. • Re-demonstrated in rodents, then monkeys, in 1990s. • Demonstrated in humans with terminal cancer in 1998. Agreed. 16
Highly correlated with learning: Plasticity occurs in the Hippocampus & Association cortex STUDI Course, August 2012 17
Correlation, yes… but causation? STUDI Course, August 2012 ? Neurogenesis Learning 18
(2010) New neurons and new memories: how does adult hippocampalneurogenesis affect learning and memory? http://www.ncbi.nlm.nih.gov/pubmed/20354534 STUDI Course, August 2012 Study employed rodents and predictive computer models “…whether increased neurogenesis is responsible for cognitive improvement remains to be tested...” “…studies that directly investigated the effect of depletion of adult-born DGCs on an animal’s cognitive ability have generated inconsistent results.” 19
THEN STUDI Course, August 2012 IF Neurogenesis Learning BUT IT DOESN’T CONSISTENTLY INTERFERE WITH LEARNING, SO….??? 20
(2012) The age of olfactory bulb neurons in humans. http://www.ncbi.nlm.nih.gov/pubmed/22632721 STUDI Course, August 2012 Study examined humans exposed to radioactivity from nuclear bomb tests “…that there is very limited, if any, postnatal neurogenesis in the human olfactory bulb. This identifies afundamental difference in the plasticity of the human brain compared to other mammals...” SO, IT’S RISKY EXTRAPOLATING FROM RATS TO HUMANS, WHEN IT COMES TO NEUROGENESIS… Yeah, but that’s the OLFACTORY part, not the HIPPOCAMPAL part… 21
(2012) Neurogenesis and progenitor cells in the adult human brain: A comparison between hippocampal and subventricular progenitor proliferation. http://www.ncbi.nlm.nih.gov/pubmed/22539366 STUDI Course, August 2012 Abundant “parent” cells in hippocampus/SGZ Few “parent” cells in hippocampus/SGZ Robust post-injury neurogenesis, compared to olfactory/SVZ Minimal post-injury neurogenesis, compared to olfactory/SVZ SO, IN THE HIPPOCAMPAL PART, RATS AND HUMANS EXHIBIT SIGNIFICANT CONTRASTS WHEN IT COMES TO NEUROGENESIS… 22
(2012) The social environment and neurogenesis in the adult mammalian brain. http://www.ncbi.nlm.nih.gov/pubmed/22586385 STUDI Course, August 2012 Why? Because BBE often touts “prosocial” teaching strategies. • “As experimentally manipulating the social environment to examine its effects on adult neurogenesis in the human brain is impossible, the majority of studies examining alterations of adult neurogenesis in humans have focused on comparisons between healthy people and those with neurodegenerative diseases (Sierra et al., 2011).” 23
What is wrong with neuroscience???? STUDI Course, August 2012 • Can’t do definitive experiments on humans, except for those who are SO sick, they are desperate • Animal studies may not be applicable • Sick human studies may not be applicable • Everyone’s chasing the big bucks: medicine • “Translational research” • “Entrepreneurs” exploit the notion that “neuroscience is too hard and/or moves too fast” for educators to keep up • “So buy our BBE product instead!” 24
Case in point: Brain Gym® STUDI Course, August 2012 • http://www.braingym.org/ • Widely adopted in British schools • Scotland spent at least US$200,000 on it • Support for the method comes from “countless anecdotal stories reported to us since 1986” • Their proprietary yawn that “promotes oxidation” of the brain • Their Brain Buttons® exercise that “promotes blood flow to the brain” 25
What is wrong with neuroscience???? STUDI Course, August 2012 • Can’t do definitive experiments on humans, except for those who are SO sick, they are desperate • Everyone’s chasing the big bucks: medicine • “Entrepreneurs” exploit the notion that “neuroscience is too hard and/or moves too fast” for educators to keep up • “So buy our BBE product instead!” • And nothing sells like “neuro”! 26
Neurowater® family of “functional beverages” STUDI Course, August 2012 27
“New neuroscience evidence proves that boys and girls learn differently.” STUDI Course, August 2012 • Not demonstrated, and very possibly not true. • Quality of the evidence is SO bad that I refuse to teach brain differences in my Biology of Gender course. • Delusions of Gender by Cordelia Fine • Brainstorm: The Flaws in the Science of Sex Differences by Rebecca Jordan-Young 29
Thank you! Happy to take questions. 30
Eric Jensen A leader in the brain-based movement, But not a neuroscientist STUDI Course, August 2012 http://www.jensenlearning.com/critics.php “…has made over 45 visits to neuroscience labs…” “…is working on his PhD in Human Development…” “…a current member of the Society for Neuroscience…” Revised edition of Brain Based Learning: the New Paradigm of Teaching (2008) equated glia with interneurons; to a neuroscientist, that is like someone saying “I’m not a farmer, but I’m an expert on farming, and this is my prize steer:”