5. Messages from Modern Brain Research

Note: This section is heavily influenced by James Zull's essay [20].

This is the Decade of the Brain, an exciting period of advances in neurobiology that (along with work in related areas, such as genetics) may lead to biology dominating the scientific agenda of the 21st century in the same way that physics dominated the 20th. This work builds on research with animal models and with epileptics who have had split-brain surgery, but the most exciting advances have come from imaging techniques -- CAT, PET, MRI. We can now study functioning human brains, normal and otherwise. For example, this research has shown that serious mental disorders, such as schizophrenia and bipolar disorder, are biological in origin, and this has led to new classes of psychoactive drugs that are much more effective at controlling symptoms of these disorders. More to the point at hand, we now have some biological insights into the processes of reasoning, memory, and learning in the normal brain.

An important message of brain research for learning is ''selection, not instruction.'' To explain this, Gazzaniga [7] uses an analogy with immunology. It used to be thought that challenges to the immune system ''instructed'' it to create antibodies. But we now know that we have at birth all the antibodies we will ever have, and the external challenges select certain antibodies to become active, much as environmental pressures result in natural selection of some traits and suppression of others in evolution. Indeed, evolutionary theory tells us that at birth we have not only our entire immune system, but our entire neural system as well -- and that neither has changed significantly in the last 10,000 years.

Learning takes place by construction of neural networks. External challenges (sensory inputs) select certain neural connections to become active, and this is a random selection among many possible connections that could occur, not something that happens by deterministic design. The sensory input enters the brain through old networks -- there aren't any others. The input can trigger either memory, if it is not new, or learning, if it is new. The cognitive psychology term for this process is constructivism: The learner builds his or her own knowledge on what is already known, but only in response to a challenge or ''disequilibration.'' In particular, knowledge is not a commodity that can be transferred from knower to learner.

Selection also means that some potential neural pathways are not selected, that is, they become dormant through lack of use. Infants have the neural equipment to learn every human language, and they do learn the one(s) that occur in their environment. But they don't learn their ''native'' language by instruction or imitation. (Proof: Babies don't speak the ''baby talk'' they hear from their parents.) Their abilities to learn unheard languages atrophy, and, as we know, the later one tries, the harder it is to learn another language. The message for collegiate education: If we want to foster such skills as problem solving, creative thinking, and critical thinking, our task is much easier if educational challenges have been developing these skills from infancy. We have a stake in what happens at all levels before college.

Memory is an intricate collection of neural networks. Most experiences initially form relatively weak neural connections in ''working memory,'' which is necessarily of short duration. The biochemical connections become stronger with use, weaker with disuse. The stabilized networks of long-term memory are accessed mainly by numerous connections to the emotional centers of the brain, but working memory has hardly any connections to the emotional brain. That is, working memory is not related to emotions -- just facts -- but formation of long-term memory strongly involves emotion [5], [12]. The message: We need to stimulate emotional connections to our subject matter if we expect it to transfer to long-term memory.

Similarly, there are strong connections between the emotional and rational centers in the brain. Indeed, emotional pathways can sometimes direct rational decision making before the learner is consciously aware of the decision process. It's not hard to see the evolutionary connection here. Since all of these structures are 10,000 years old, they are intimately related to fight-or-flight reactions and other survival strategies [5].

Just as emotion is linked in the brain to learning, memory, and rationality, so are the motor centers of the brain, and by extension, the rest of the body. Body movement facilitates learning -- sitting still inhibits learning [9].

We have already linked brain research to constructivism. Now we connect with Kolb's learning cycle. The concrete experience (CE) phase is input to the sensory cortex of the brain: hearing, seeing, touching, body movement. The reflection/observation (RO) phase is internal, mainly right-brain, producing context and relationship, which we need for understanding. Because the right brain is slower than the left, this takes time. The abstract conceptualization (AC) phase is left-brain activity, developing interpretations of our experiences and reflections. These are action plans, explanations to be tested. They place memories and reflections in logical patterns, and they trigger use of language. Finally, the active experimentation (AE) phase calls for external action, for use of the motor brain. Thus deep learning, learning based on understanding, is whole brain activity. Effective teaching must involve stimulation of all aspects of the learning cycle [20].

In addition to the references already mentioned, [5] and [6] are useful for understanding brain research and its relevance to learning. Reference [18] is a non-technical (but well-documented) presentation for educators of the implications of this research for curriculum and pedagogy.


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| Reform or Renewal? | Students | Problems |
| Cognitive Psychology |
| Technology and Learning | Technology and Curriculum |
| Renewal in Calculus Courses | References |