Social and Cultural Foundations of American Education/Knowing/Brain Research

What do we know about brain research?

Brain research is an important field dedicated to helping us learn how our brains function. This knowledge will help us better understand how we learn and some important differences between the brains of children and adults. As educators it is crucial that we have an understanding of the biology that is affecting how our students learn.

Technology Used During Brain Research

CAT Scans

Computerized axial tomography (CAT) scans are one imaging technique that is used to create an image of the brain. It consists of multiple X-ray exposures which are combined by a computer to create image slices of the brain. This is particularly useful when looking at interior parts of the brain. CAT scans however pose the same radiation risks as other forms of X-ray and therefore are used less regularly in brain research than for personal diagnoses of abnormal anatomy (Barlow & Durand, 2005).

PET Scans

To measure brain function a positron emission tomography (PET) scan can be used. A tracer substance attached to radioactive isotopes is injected into the blood where it interacts. When parts of the brain become active blood is sent to deliver oxygen which creates spots which are picked up by detectors and used to create a video image of the brain during a particular task (Barlow & Durand, 2005). PET scans are costly and invasive, making their usage limited.

MRI and fMRI

Magnetic resonance imaging (MRI) and functional magnetic resonance imagining (fMRI) are commonly used brain imaging techniques which use echo waves to discriminate between grey, white and cerebral spinal fluid (Giedd, Blumenthal, Jeffries, Castellanos, Liu, Zijdenbos, Paus, Evans & Rapoport, 1999). MRI is noninvasive, poses little health risk and can be used on infants and in utero providing a consistent mode of imaging across the development spectrum (Lenroot & Giedd, 2007). MRI is used to create an image of the brain structure and fMRI, which is really a series of MRIs, measures the functioning of the brain through computer adaptation of many images (Barlow & Durand, 2005).

Structure of the Brain

The brain is composed of over 140 billion nerve cells, called neurons, by the time we reach adulthood. Unique live experiences and biological processing means that individual brains contain the potential to become drastically different. However, the brain is generally organized into several lobes that control categorical parts of life. The brain stem handles most of the essential automatic functions including sleeping, breathing, pumping of the heart and digestion. Parts of the brain stem, the hippocampus, thalamus, hypothalamus and limbic system are largely involved with controlling behavior and emotions; especially stress responses (Barlow & Durand, 2005).

The cerebral cortex is distinctly human and houses two hemispheres which are responsible for all our cognitive functions. Each hemisphere consists of four separate lobes: temporal, parietal, occipital and frontal. The temporal lobe recognizes various sights and sounds and is responsible for long-term memory storage. The parietal lobe recognizes touch sensations. The occipital integrates and understands visual inputs. The frontal lobe is responsible for our thinking and reasoning abilities as well as memory and is the most interesting for educators because it continues to grow well into adulthood. The hemispheres are connected through a structure called the corpus collasum which allows collaboration between different brain regions housed in opposite brain hemispheres (Barlow & Durand, 2005).

Brain Development

Early Childhood

Although the brain is well organized into lobes there is a great deal of plasticity available. Depending on the person and their environment different parts of the brain may be more or less developed (Slavkin, 2004). Proper development of all brain sections begins in early childhood with an enriched environment composed of proper nutrition and interaction with attentive caregivers. Development of the brain occurs through sensitive periods where exposure is necessary for proper growth. If young children are not adequately exposed to visual, auditory and tactile stimulus they risk underdevelopment. Some of these critical periods include visual development between the 2nd and 8th month of life, motor development between the 5th and 12th month of life, and the limbic system development from birth to the 3rd month of life. The frontal lobe and language skills also have a critical period which is much longer and spans most of early and middle childhood. (Murray, 2007).

Does ADHD affect brain development? Neuropsychological deficits have been identified in Attention Deficit Hyperactivity Disorder (ADHD) populations. The physiological areas of the brain where the largest deficits are noticeable are in the frontal and frontostriatal networks that support inhibition in normally functioning children and adults (Wilens et al., 2002). The wide spread implications that deficits in the frontal lobe cause in ADHD children include disinhibition, lack of attention, and distraction in working memory. Additional deficits in verbal memory, processing speed and motor speed have recently been identified in ADHD children (Hervey, Epstein & Curry, 2004). Remembering the plasticity of the brain during childhood it is reasonable that a child with ADHD may improve if lower functioning parts of the brain are encouraged to grow through an enriching understanding classroom and home environment.

Middle Childhood

As development continues into middle childhood there is an increasing amount of specialization in the brain and integration between brain regions. This process is accomplished through the pruning of unnecessary neurons. Specialization is essential for the development of language, reading, numerical computations and higher level reasoning. For example, the development of reading is characterized by orthographic processing in the occipital lobe, phonological and semantic processing in the temporal lobe, syntactic processing in the frontal lobe and integration in the parietal lobe (Booth, 2007). While each part of the brain is responsible for individual functions involved in reading the whole brain must function together to create the result of a child who can read. It is important for educators to realize that young minds are in the process of growing, pruning and strengthening connections.

Adolescence

The adolescent brain continues to build upon the specialization which occurred during childhood. It is focused on increasing myelination of neurons, a process that allows information to travel faster and integrate better in the brain. Analyses of brain images from adolescents indicate that the process begins at the back of the brain in the occipital lobe and moves toward the front, ending in the frontal lobe (Balkemore & Choudhury, 2006). The increasing of myelination is the reason adolescents more closely resemble adults in their cognitive abilities. The frontal lobe, which is the last to receive this myelination processes is responsible for higher level reasoning and impulse control and the immaturity of this region in adolescence contributes to the reputation of reckless behavior during the teen years (Durston, Pol, Casey, Giedd, Buitelaar & Engeland, 2001).

There is also a lateral change in the brain during adolescence. The right and left hemispheres become more connected and are better able to communicate across the corpus callosum. This development means the hemispheres can work more quickly together to process language, math, and spatial problems. This interconnection is also related to increases in long term memory as memories are better coded across different regions and more easily retrieved into a cohesive entity (Durston et al. 2001). One study has found that this maturation of the brain may continue well into a person’s 20s or 30s and that full brain maturity may not be reached until well after puberty (Balkemore & Choudhury, 2006).

The Influence of Stress on Brain Development

In today’s schools children are constantly dealing with outside stressors, influences that affect their ability to pay attention and learn. Stress has been shown to have a profoundly negative effect on the developing brain which results in a lower level of learning. Stress can affect neurophysiology before the child is even born. Monk found that stress hormones crossed the placenta in unborn children and caused a rise in fetal heart rate and cortisol, a stress neurohormone, levels (Monk, Fifer, Myers, Sloan, Trien & Hurtado, 2000). Increased levels of cortisol in infancy, childhood or adolescence have been correlated to a later inability to deal with stress and stunted cognitive development. This is because chronic stress leading to chronic secretion of cortisol may cause neuron death in the hippocampus, which leads to cognitive deficients (Barlow & Durand, 2005). The hippocampus is located in the brain stem, which indicates that children who are using their hippocampus area to regulate stress may not be spending valuable time developing other regions of their brains, those necessary for higher level reasoning and social skills development. These children quickly find themselves falling behind in school which perpetuates the stress cycle.

Conclusion

As educators the more we know about our students the better able we are to adjust our classrooms and create an environment that helps all students to excell. Children through out development are experiencing changes and learning how to use their brains to store and retrieve information. It is important to present information in such a way as to maximize a student's effort. Stress can also affect the amount of information a student can process. By creating classrooms that are safe and secure we can help to improve the brain power of our students. When teachers understand the child's brain better we can be more effective educators.

Multiple Choice Questions

Click to reveal the answer.

You are designing a research study on first graders. Which imaging technique is least likely to be approved by the IRB?

A. PET scan

B. CAT scan

C. DOG scan

D. MRI

B. CAT scan

Following a brain injury, one of your students has trouble hearing. Which part of the brain was damaged?

A. Occipital Lobe

B. Corpus Callosum

C. Hypothalamus

D. Temporal Lobe

A child is removed from an abusive home at 4 months. In what area is there the greatest chance of insufficient cognitive development?

A. Visual development

B. Motor skills

C. Social skills

D. Musical abilities

A. Visual development

What is the best way to improve the performance of children with ADHD?

A. Use high doses of medications.

B. Allow the child to participate in an enriching classroom.

C. Encourage them to watch lots of TV at home.

D. Do nothing.

B. Allow the child to participate in an enriching classroom.

How can mothers improve cognitive functioning in their children?

A. Avoid high stress situations during pregnancy.

B. Allow children to stay up late at night.

C. Leave children alone and unsupervised most of day.

D. Watch educational television everyday.

A. Avoid high stress situations during pregnancy.

Essay Question

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How can a teacher effectively influence brain development in students?

There are many factors that affect brain development throughout childhood and adolescence. Parents, teachers, the community and students are all responsible for challenging and supporting students as their brains continue to grow and learn. Teachers can create a positive influence on brain development by creating an age appropriate curriculum, a thoughtful classroom schedule and reducing stress in the classroom.

It is important that teachers choose lessons that are neither too easy nor too hard for students. Students who continually solve simple problems receive no growth and quickly become bored. Children who are constantly struggling with material that is developmentally beyond their reach will become frustrated and despondent. Teachers, through the use of an age appropriate curriculum, can guide children to learn language and reasoning skills that greatly influence brain growth.

A classroom schedule should be created that allows children enough time to become engaged in lessons and learn important information without overtaxing attention spans. Information that is presented after a child is distracted will not be retained and is wasted.

Similarly, information that is learned while a student is under a great deal of stress may not be effective. While a student is stressed her body responds primitively and predominantly uses the hypothalamus and other lower brainstem areas of the brain. With a focus on these areas other areas of the frontal brain are neglected. It is important that the classroom be a calm and inviting place where all children feel comfortable. This is especially important during lessons, when learning is taking place and during testing when children are required to use their frontal lobes for higher order reasoning.

There are many influences on brain development and it is important for teachers to realize they can manipulate their classrooms to help children use and grow their brains beyond their potential.

A teacher can effectively influence brain development by continuing to be consistent with their teaching methods. The earlier the stimulation occurs, will build the path for development of the brain. Negative or lack of stimulation could possibly make the development of the brain difficult or impossible. The article states that the exposure of the brain occurs during normal growth periods which are throughout a student’s education career.

A teacher should use teaching methods that will prove to be affective for each student individually. If one student understands but another doesn’t, the child who doesn’t understand is not processing the information in their brain. To effectively influence the brain, a teacher must create a environment where there is little stress. Stress can play a big factor on how students process information, little stress will allow a student to develop higher levels knowledge and better social skills.

A good environment at home is needed also. The teachers and the parents should work together so that the student is developing to their full potential. Positive Reinforcement should be use at school and at home to encourage the students to continue with their education. Encouragement will reduce the level of stress so that the student feels good about themselves which will lead to better development of the brain.

Teachers must work with their students to the best of the knowledge to insure that they are receiving the best education and brain development that they can offer. Teachers are there to build the foundation of a child’s brain so that it can grow and develop to its full potential. —Cassie Gray