I’m a Neuroscientist. Here’s How Teachers Change Kids’ Brains.
By Martha Burns
Teachers change brains. While we often don’t think of ourselves as brain changers, when we teach we have an enormous impact on our students’ cognitive development. Recent advances in educational neuroscience are helping educators understand the critical role we play in building brain capacities important to students’ learning and self-control.
To understand how teachers change the brain, we need to begin with a reasonably new understanding of the biology of learning. The human brain is an experience-dependent organ. Throughout our lives, the cerebrum—the largest portion of our brain—fine-tunes itself to adapt to the world around us. The scientific term used to describe this is “neuroplasticity, ” which involves three processes.
- Proliferation is associated with brain building, and is highly dependent on childhood experiences like play, socialization and hearing stories read aloud. It involves creating new synaptic connections and fiber tract connections.
Prior to birth, proliferation is largely dependent on our genes, but once a baby is born, experiences in the external world exert their influence. The early years become the “set-up” period in which the brain maps and organizes based on the child’s world. For example, the predominant language (or languages) and familiar faces, voices and objects will become the data the brain uses to build new cortical maps and their interconnections.
- Pruning is another process involved in setting up the brain. Our efficient brains depend on eliminating connections that are not behaviorally relevant or useful. This competitive elimination process is also based on experience and results in pruning areas not used. This pruning includes reduction in unused synapses (new connections that represent new knowledge) and axonal fiber tracts (the highways that allow newly learned information to integrate with past knowledge and experience).
An example is the elimination of auditory perceptual connections that might be helpful for learning a foreign language, making it more difficult to learn a second language as we age.
- Consolidation is the third process occurring during early brain maturation, which helps us respond to things automatically, without thinking. The human brain is a statistical analyzer. After thousands of repetitions of slightly disparate stimuli, it begins to map for commonalities. That allows the brain to develop anticipatory response patterns, or a set of common reactions, which minimize effort and increase speed and efficiency.
It is through these set-up processes that the brain efficiently adapts to each different environment. Scientists used to refer to the early set-up years as a “critical period,” but they now recognize that brain building continues throughout life, albeit at a slower pace and less dramatically as we age.
So this early set-up stage—occurring from birth to age five—is now often referred to as an “optimal” or “sensitive” period because the brain can continue to proliferate, prune and consolidate after the period ends, with the right kind stimulation. Hence, the role of teaching.
After the optimal period ends, teachers can maximize this neuroplastic process through content, intensity and methodology.
Content: The “what” of teaching
We start with educational content. Of course, content must be appropriate to students’ age and prior knowledge, but students also need supportive cognitive capacities.
For example, attentional skills, working memory and processing skills are essential for learning. When a student has issues with one or more of these skills, it affects academic performance irrespective of the teacher’s skill.
This is an area where scientific research guides us to select not only the most effective content, but, when necessary, neuroscience-based interventions to build cognitive capacities.
Finally, as learning proficiency improves, the teacher must continuously adapt and personalize the instruction to match the student’s level of knowledge and ability.
Intensity: The “when” of teaching
Repetition is essential for learning. It assures mastery and efficiency with the content. This is why educational neuroscientists often state that “practice makes permanent,” in contrast to the more popular “practice makes perfect.”
For this reason, instruction and practice must occur with enough frequency and intensity to drive brain reorganization. We might simplify this as the “when” of teaching, although it also includes “how often” and “how long” a given topic is taught. For the most part, content can be incrementally delivered over weeks and years because we are adding to information already stored and organized for efficient processing. For example, vocabulary building continues over a lifetime as long as new vocabulary items represent familiar concepts in our native language.
At the same time, teachers are also driving the brain to reorganize. Good examples are the intensity needed to learn a new language or to address structural differences in the brain associated with poverty. A student who is an English language learner, for example, must be able to perceive the speech units of English and internalize that set of sounds, in addition to learning vocabulary and grammar.
For children of poverty, limited experiences can affect cortical maturation in the language and other areas of the brain important for learning. Because approximately 80 percent of teaching involves the teacher speaking and students listening, that language rich environment can help to build those language areas that are not as mature among children of poverty, as long as the language level the teacher uses matches that of the student with limited language experiences.
Early reading teachers also understand that students need to be able parse words into their component sounds before they can match letters to sounds for decoding. Research suggests that for some students, the inability to perceive those speech sounds may interfere with learning to decode so supplementary interventions that emphasize those skills can be very helpful to “ready” the student to learn.
Methodology: The “how” of teaching
The acronym ReNEW (Reinforcement, Novelty, Enhanced attention and Well-being) summarizes how teaching drives the brain to change after the optimal period. Brain research on the effects of teaching has looked at the impact of naturally occurring chemicals in the brain that are driven by environmental factors leading to neuroplastic change.
Reinforcement and novelty. An important neuromodulator of brain plasticity is dopamine. Dopaminergic systems act as the “save” button in the brain. Dopamine released during carefully timed and structured reinforcement, as well as during novel experiences, increases the likelihood that newly-learned information will be retained permanently.
Attention. A learner will not benefit from our instruction unless they actively attend to us—meaning it pays to shake up your teaching sometimes. Attention is enhanced when neuromodulators like acetylcholine and norephinephrine are stimulated through educational interaction that is engaging with some novelty. We might call this the “wow” factor. Teachers can enhance attention by simply maintaining eye contact, moving around the classroom, interacting with students and assuring that before any instruction the students are engaged.
Well-being. Serotonin is associated with a feeling of well-being and is a powerful modulator of neuroplasticity. As teachers, we are very familiar with the importance of enhancing students’ sense of trust and confidence in the educational process, which can help increase serotonin levels in a positive way.
Teachers do not just impart information, although that is certainly part of what we do. Teachers are also drivers of neuroplastic change through the targeted, systematic consideration of the content we include, the intensity of our instruction and assurance of adequate repetition. Effective teaching—and, when necessary for struggling students, neuroscience-based interventions—enable us to reach every student.
Martha S. Burns, Ph.D., is an adjunct associate professor at Northwestern University, and serves as the director of neuroscience education at Scientific Learning.