Learning Disorders and Brain Organization

More than ever parents and schools are looking for ways to help children deal with learning problems, and the number of children diagnosed as having a learning disability (LD) has tripled in recent years. Definitions and criteria for learning disabilities and/or learning problems have been inconsistent. However, as advances in technology, such as brain scans, become more sophisticated, science is providing clues as to how learning actually occurs - .how information enters the brain, is processed, stored and then used in language or movement. Identification and teaching methods are also benefiting from new knowledge in the science of learning. Neuropsychologists, child psychiatrists, and other professionals are able to identify children at risk and to design targeted instruction. The importance of early intervention to forestall later learning and emotional problems is critical.

In this issue of the NYU Child Study Center Letter, we describe the symptoms associated with learning problems, how a neuropsychological learning evaluation examines the way in which brain functions affect the learning process, specifically in the domains of language, memory, executive functioning, visual skills and sensorimotor functioning. Also discussed are the ways in which this diagnostic information is used to construct a profile of a child's learning style and academic functioning, as well as classroom recommendations.
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Introduction

Sometimes bright kids have trouble learning.

Matt, in 3rd grade, can't seem to spell simple words and often reverses letters and numbers. He had trouble in kindergarten learning to rhyme words and write his name.

Arnold, in 4th grade, can understand complex math problems, but can't seem to add 5 + 7 accurately. He can't tell time and confuses left and right.

Nicole, in 6th grade, can express her ideas well verbally, but can't organize and write them. She has trouble producing an outline for essays.

Jennifer, in 8th grade, reads quickly and accurately, but has difficulty getting the point of stories or comprehending her history and science texts. She can't remember the sequence of the events in the stories nor can she recall specific facts.

In addition, parents, teachers, psychologists and other school personnel have other concerns; they may report that a child

•     is inconsistent in learning
•     can't sustain his attention
•     struggles with homework
•     has uneven academic achievement
•     has not mastered the specific skills expected by a certain age or grade
•     has difficulty organizing or prioritizing assignments

Learning involves the integration of a complex set of tasks. In order to acquire and use new information, the brain has to receive, process, analyze and store this new information. Because of recent advances in technology, we now know more about how the brain works. When a bright kid, or any kid, has trouble learning, a neuropsychological evaluation, using both quantitative and qualitative observations, can investigate the child's abilities to process information of many different types and to make sense of that information. A neuropsychological evaluation can help parents, teachers, as well as the child, know more about how she learns and how she can improve learning.

Taking a closer look: what happens during a neuropsychological learning evaluation?

A battery of tests, which yields a profile of the child's strengths and weakness across several domains, or areas, of functioning is administered. Many of these tests are standardized, which means that the child will be compared to large groups of children in the United States of the same age. The battery may include measures of intellectual functioning, language abilities, memory functioning, and academic achievement. In addition, specific neuropsychological tests which examine attention/concentration, visual spatial/visual-motor/visual perceptual skills, sensorimotor functioning, and executive functioning may be included. These tests assess the child's competence in the basic cognitive abilities that lay the foundation for learning. Social/ emotional/behavioral issues are also taken into consideration.

To provide information on a child's learning profile, two models of analyzing test results are often used: l) a discrepancy model which looks at uneven performance among and between tests and subtests, and 2) a deficit domain model which looks at specific deficits in the domains described above. A general knowledge of the functions of the cerebral cortex of the brain can be helpful in analyzing a child's learning strengths and weaknesses. Some basics to keep in mind:

The brain is made up of two hemispheres, the left and the right hemisphere. Both hemispheres process information from all sensory modalities. Each hemisphere regulates the motor skills on opposite sides of the body.

Damage or altered development in one hemisphere may cause either diminished functioning or augmented functioning in other hemisphere.

Left hemisphere

• is dominant for speech in most people
• is associated with formal logic, science-mindedness, attention to details, the words of emotion
• controls reading, writing, understanding and speaking, verbal thinking and verbal memory
• processes information in a linear, sequential, serial, time-oriented fashion damage can cause aphasias (trouble with understanding or using language), verbal memory loss, concrete thinking, learning disorders, poor complex motor movement

Right hemisphere

• mediates complex non-verbal material associated with intuition, nonverbal perceptiveness, inspirational hunches, uncritical imagination, nonverbal emotional processing
• processing and storage of visual, tactile, spatial, music information
• Gestalt thinking, holistic, simultaneous processing, synthesis
• damage can cause verbosity, poor judgment, organization, processing of complex information, inferential thinking, spatial organization, math, construction, insight

Although there is not a one-to-one connection, each area, or domain, of functioning is assigned to an area of the brain, so that if we know that a certain domain is disrupted, it means that an area of the brain is not working well or is not wired as expected. For example, memory is controlled by several areas; language is most often on the left side of the brain (temporal lobe on the figure); executive functions are in the front as are motor skills (frontal lobe and primary motor cortex on the figure), and visual skills are located in the back of the brain (occipital lobe and portions of the parietal lobe on the figure).

The following principal domains of functioning may be assessed and a profile of strengths and weaknesses can be developed. The evaluation procedure may include measures of the different skills that represent the brain's functioning. These include:

Intellectual Functioning

A measure of intelligence is administered to serve as a basis for determining a child's potential and to provide a context for evaluating a child's competence. The measures that are typically used try to find out how a child approaches many different types of challenges. Measures of intelligence, what we have come to call "IQ," do not simply measure a child's ability to answer many different factual questions, but they also assess the child's ability to solve a wide variety of problems, including problems involving verbal information, visual-spatial skills, and making sense of novel material.

The most commonly used instruments are the l) Wechsler Scales, which include the Wechsler Preschool and Primary Scale of Intelligence (WPSSI- III), Wechsler Intelligence Scale for Children (WISC-IV), Wechsler Adult Intelligence Scale (WAIS-III), and 2) The Stanford Binet V. Although an overall "IQ score" is calculated from the child's performance on these tests, this overall score represents an average of many different, smaller subtests and thus may be less meaningful for understanding the child than a closer evaluation of the child's performance across the different, smaller measures.

Language Domain

An evaluation looks at language from its smallest unit (the sound) to its most complex units (sentences, paragraphs) and examines how a child takes in or understands language and how the child expresses herself.