The Learning Brain: Core Concepts: Theory & Research: Universal Design for Learning: CAST

PET scans and other advanced imaging techniques enable neuroscientists to study the learning brain in action. These tools can generate images of the brain during a learning activity such that highly active regions can be distinguished from those that are less active. PET measures glucose metabolism. The more active a region is, the more glucose it metabolizes. Increased glucose metabolism and, thus, activity results in the generation of a brightly colored �hot spot� on the scan. The greater the activity, the more intense the hot spot, and the more brightly colored its appearance on the scan. Patterns of hot spots viewed while an individual is performing different learning tasks generate information about how the brain works as we learn.

Recent neurological findings confirm earlier descriptions of three spatially and functionally distinguishable but interconnected networks in the learning brain. Broadly speaking, one network recognizes patterns, one generates patterns, and the third determines priorities.

Recognition Networks

Photograph of old style printing press letters.

Most of the posterior (back) half of the brain is devoted to recognizing patterns. These recognition networks make it possible to identify patterns such as voices, faces, letters, and words, and more subtle patterns like author style and nuance. In academic learning, the recognition networks are essential for identifying basic patterns such as letters and words, or more complex patterns like paragraph structure or the relationship between a mathematical formula and its graphical representation.

Damage to the recognition networks can affect the brain's capacity to know what things are. Depending on the degree and kind of damage, an individual may lose the ability to recognize objects by their color or shape, by the way they move, or by the way they sound. Normal variation in people's ability to recognize pitch, timing, location, color, orientation, or shape is largely due to differences in the amount of cortex or extent of neural networking allocated to visual, auditory, and olfactory recognition. See Chapter 2 of Teaching Every Student in the Digital Age (http://www.cast.org/teachingeverystudent/ideas/tes/chapter2_3.cfm).

Strategic Networks

The networks responsible for knowing how to do things and generating patterns like holding and moving a pencil, riding a bicycle, speaking, reading a book, planning a trip or writing a narrative are located in the frontal lobes (anterior cortex). These are called strategic networks for their importance in pattern generation. The strategic networks are critical for all learning tasks. They work in tandem with recognition networks to learn to read, compute, write, solve problems, plan and execute compositions and complete projects.

Damage to different parts of the frontal lobes can lead to difficulty in planning and organization, poor fine or gross motor coordination, impulsive behavior or paralysis. Physiological differences in frontal networks account for much of the normal individual variation in fine motor skill, physical coordination, and capacities for planning, organization, and strategic thinking. See Chapter 2 of Teaching Every Student in the Digital Age (http://www.cast.org/teachingeverystudent/ideas/tes/chapter2_5.cfm).

Affective Networks

At the core of the brain (the limbic system) lie the networks responsible for emotion. Neither recognizing nor generating patterns, these networks determine whether the patterns we perceive are important and help us decide which actions and strategies to pursue. Via the affective networks we pursue goals, develop preferences, build confidence, persist in the face of difficulty, establish priorities, and care about learning. Recent neurological work shows that the capacity to determine which patterns count is critical to human intelligence and to all learning.

Damage to the limbic system can impair our ability to establish priorities, select what we value or want, focus attention, or prioritize actions. Thus we now know that physiological as well as experiential factors contribute to individual variation in confidence, persistence, concentration, and other affective factors. See Chapter 2 of Teaching Every Student in the Digital Age (http://www.cast.org/teachingeverystudent/ideas/tes/chapter2_7.cfm).

Individual Differences

Learning requires complex interactions of the recognition, strategic, and affective networks. While everyone's brain functions take place in roughly the same areas and work together in roughly the same way, PET studies have shown that each individual has his or her own activity "signature." Each of us has a different functional allocation of cortex. For example, some people have larger regions devoted to recognizing patterns, generating strategies, or focusing on particular priorities. These differences seem to be reflected in different types of learning style, strengths and weaknesses, and varying "kinds" of intelligence (see the work of Howard Gardner http://www.cast.org/udl/index.cfm?i=152#s1).

Thinking about individual differences in light of the three brain networks can help us understand the ways in which curriculum must be flexible to reach all learners. Multiple representations of content can adjust to the recognition networks of different learners, multiple options for expression and control can adjust to the strategic and motor networks of different learners and multiple options for engagement can adjust to the affective networks of different learners. See Chapter 4 of Teaching Every Student in the Digital Age (http://www.cast.org/teachingeverystudent/ideas/tes/chapter4.cfm).