Differentiation and the Brain - David A. Sousa

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threatening bodily injury, are processed immediately. When the stimulus is received, a rush of adrenaline is sent throughout the brain. This reflexive response shuts down all unnecessary activity and directs the brain’s attention to the source of the stimulus.

      Emotional data also take high priority. When an individual responds emotionally to a situation, the limbic system takes command and suspends complex cognitive processes. We have all had experiences when anger, fear of the unknown, or joy quickly overcame our rational thoughts. Under certain conditions, emotions can enhance memory by causing the release of hormones that signal brain regions to strengthen memory. In other words, strong emotions can simultaneously shut down conscious processing during an event and enhance our memory of it. Emotion is a powerful and misunderstood force in learning and memory.

      The brain’s reaction to both survival stimuli and powerful emotions is reflexive; that is, it occurs instinctively and without prior planning. If neither threats to survival nor strong emotions are present, the brain can turn its attention to processing factual information and concepts. This reflective process allows learning to take place by making connections to previous experiences and building cognitive networks.

      Another way of stating the hierarchy illustrated in figure 2.1 is before students will turn their attention to cognitive learning (the curriculum), they must feel physically safe and emotionally secure.

      Students must feel physically safe and emotionally secure before they can focus on the curriculum

      The belief that students want to succeed relates to the growth mindset we discuss later in this chapter. The human brain does not deal well with failure. If a student is not learning, the teacher must determine how to modify his or her teaching style and instructional material to meet the student’s needs. If a teacher believes certain students are inherently lazy or unmotivated, then that negative mindset leads the teacher to respond to these students with annoyance. This response sets the stage for a negative learning environment and alters the students’ emotional state.

      Figure 2.2 (page 24) illustrates how positive and negative learning environments affect body chemistry, thereby altering the emotions and learning of those in the classroom. In positive learning climates, chemicals called endorphins are running through the bloodstream. These are the body’s natural painkillers and mood elevators. They produce a sense of euphoria, so an individual feels good about being in the situation. Endorphins also raise the pain threshold, so minor aches are no longer bothersome. Most important, they stimulate the frontal lobe to remember the situation and whatever it is processing at the moment—most likely the learning objective.

      However, in a negative learning environment, very different biochemical reactions are at work. Negative climates create stress, which elevates the concentration of the hormone cortisol in the bloodstream. This chemical is a powerful steroid that raises an individual’s anxiety level. It also prompts the frontal lobe to stop processing low-priority information, such as the learning objective, in order to focus on the cause of the stress and decide how to reduce or remove it. Thus, the frontal lobe remembers the situation, but the learning objective has already dropped out of the memory systems.

      Figure 2.2: The impact of the learning environment on body chemistry.

      Teachers who believe all students come to school desiring to learn will figure out different ways to reach and teach uninterested or frustrated students. This positive mindset has a profound impact on the ways teachers respond in the classroom, especially to struggling students. When students lose faith in their ability to learn, they often turn to counterproductive ways of coping, such as misbehaving or withdrawing. This situation is less likely to occur in a differentiated classroom, where students of varying abilities have a better chance of success and teachers’ negative assumptions are far less apt to prevail.

      Attending to students’ social-emotional needs is not a digression that draws time from teaching academic subjects, but rather an important part of classroom practice. Students are not just learning the curriculum; they are learning about themselves, how they interact with their peers, and how they choose their friends. They are also learning to deal with their emotions, such as how they react to failure and respond to the opposite sex.

      In the mid-2000s, a field of study emerged called social cognitive neuroscience. Brain-imaging technology allows researchers in this field to answer a long-standing question: Are the cerebral mechanisms and neural networks involved in social stimuli processing (for example, forming relationships, comparing others to oneself, or interpreting the behavior of others) different from those involved in the processing of nonsocial stimuli (for example, dealing with hunger and sleep)? Apparently, the answer is yes. Studies indicate specific brain regions activate when subjects face making social decisions and judgments as part of a performance task (Kilford, Garrett, & Blakemore, 2016; Mitchell et al., 2005; Olson, Plotzker, & Ezzyat, 2007).

      One surprising finding is the discovery of spindle-shaped neurons in the front part of the brain. These neurons are larger and have fewer branches than the neurons typically found in brain tissue. Called von Economo neurons (named for the man to first describe them), they are found only in human beings, great apes, and a few other distinctly gregarious animals. Researchers note the von Economo neurons are found in similar places in the brains of these animals and speculate they play a major role in generating social emotions and monitoring social interactions (Chen, 2009). Figure 2.3 shows the location of the two sites where von Economo neurons are found in humans, the anterior cingulate cortex and frontal insula (Chen, 2009).

      The neural networks that process social stimuli are different from those that process nonsocial stimuli.

      Source: Adapted from Chen, 2009.

      Figure 2.3: Two locations of von Economo neurons in the brain.

      Studies of people with a degenerative disease called frontotemporal dementia provide additional evidence of the von Economo neurons’ association with social interactions. These patients lose their social graces, show no empathy, and turn irresponsible, erratic, and insensitive. In one study, brain imaging reveals the dementia targets the neurons in the anterior cingulate cortex and the frontal insula (Brambati et al., 2007).

      Brain regions and neurons for processing social interactions suggest how important social relationships are to human development and behavior. In the brain of children and adolescents, the frontal lobe is not mature enough to exert complete control over social-emotional processing. As a result, social-emotional needs are a high priority with many students (Sousa, 2009a). Of course, a high percentage of the social interactions in schools occur between teachers and students. During a school day, many students spend more time with all their teachers than with any of their parents, siblings, or peers. This reality alone makes it crucial for the student and the teacher to perceive, assess, and respond to each other’s behavior accurately and adequately. Effective teachers recognize these needs and find ways to address them while still managing to present the curriculum objectives. However, face-to-face interaction between students and teachers is rapidly giving way to face-to-device interaction as the use of technology expands in the classroom. What are the consequences of this shift in social communications?

      Most students are growing up with technology. It is an integral part of their lifestyle. Technology, of course, can be an excellent tool for helping students

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