Learning Disorders and Brain Organization (page 2)
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. AG/HSK
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.
- 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
- 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:
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.
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.
Given the importance of understanding the components of language, the following areas, which are building blocks of language, should be assessed:
Phonology How does the child hear, sequence and process sounds? Can he blend sounds into words and understand parts of words?' (For example, if we change the /p/ in pan to /f/ it makes the word fan.)
Morphology Can the child make a connection about the general use of the ending of the word? (For example: If we say 'build' and then put 'er' on it, we have 'builder.' adding er as in teacher, painter means the word refers to a person who does that particular job.) In addition, the following aspects of language should be assessed:
Receptive language refers to the way a child listens to, takes in and understands language and is assessed by giving the child increasingly lengthy and complicated oral directions and requiring a non-verbal, pointing response. The following should be noted:
Does the child understand temporal, directional and quantitative words? (For example, in a younger child, words such as below, next to, above, half, etc.)
Is the child able to follow directions? (For example, if the teacher says take out your book, open it up to page 32, and look at the diagrams on the right side of the page).
Expressive language refers to the way a child uses language to tell what she knows.
Does the child use a wide range of vocabulary?
Does the child respond quickly or talk around the topic? A child who has trouble finding words may have concomitant problems with reading, reading comprehension, or writing.
Is the child fluent in producing language? Does she speak clearly, using full sentences, or hesitantly? Does she formulate a variety of sentence types or rely on simple sentences? Are the ideas in sequence? Is the flow of ideas logical or random?
The pragmatic aspects of language are also important.
How are the child's social skills during conversation? Does she make eye contact, wait for the other person to finish speaking before she speaks, ask a question and wait for the response? Does the child understand rules of politeness and social norms?
Metalinguistic awareness refers to the ability to take someone else's perspective. For example, when a person unfamiliar with the child's school asks him about his class routines and class requirements, can he take into account that the questioner doesn't know the teacher or the school and explain details about class procedures and rules? The ability to take the point of view of another person is important because children are constantly required to make inferences, draw conclusions and understand how someone else might think about a situation. If they're unable to do that in conversation, it is unlikely that they can do it in a more formal academic setting.
This area of functioning, which is an important component of learnng, relates to how well a child learns new information and retains it over time. The questions that will be answered by an evaluation of these skills include:
Can the child
- learn and then recall both verbal and visual information?
- remember information that is presented only one time versus information that has repeated presentations?
- recall information that is well- organized versus material that is less-structured?
An evaluation tries to approximate some of the many different ways that new information is presented to children in the real world. Although there are many different aspects to memory, five important facets of learning and remembering need to be examined in a neuropsychological assessment.
Registration and short-term storage is a very short process in which a child is alert to information and keeps it in mind for a very short time. This process is related to attention and lasts about 30 seconds; after that point the information can be lost. Thus, if the child becomes distracted or is not paying attention to what she wants to remember, the new information cannot be recalled.
Working memory is a process in which a child may hold on to information for a longer period of time and has that information available to use. This process can last anywhere from 30 seconds to one hour. For example: When someone tells you their name or telephone number, that new information can be available to you for a short while after you have heard it, and it may be available to you for a longer time if it is particularly meaningful. In a classroom, working memory is important because sometimes a child must hold in mind some new information even when other things are happening. For example, a child may need to write down the homework while everyone else is packing up their bags. This child will need to recall what the teacher said so that she can write it down accurately. (Working memory, both verbal and non- verbal, plays a crucial role in executive functioning, discussed in the next section)
Consolidation is the process through which information is taken from working memory and is processed in order to form a more lasting memory. Consolidation can last from the point at which that information is registered and can go on for years. A person may take in information in the form of a picture or in the form of words; consolidation, or integration, means that the mind does something with the information, works on it and puts all the pieces of information together. Consolidation may take longer for some children than for others. For example, a child who sees a picture during the day and goes to sleep, may wake up later and remember more details about the picture than she could the day before. Her mind has been integrating and digesting the information and thinking about it even though she's not consciously aware that this is happening.
Long-term storage is the process that we typically think of when we talk about memory. Long term storage refers to how a child takes in information and stores it away in the file cabinet of his mind so that he can have access to it later. He can retrieve the information and use it in the service of new learning, he can attach new meaning to old information, or he can use that old information in a new way.
Retrieval and recognition is the process involved in getting the information out of the file drawer. It refers to information filed away (vocabulary words, stories, etc.) and to how a child gets that information out and then demonstrates knowledge of the information through drawing or speaking or writing. Retrieval and recognition are different processes: retrieval means that the child accesses learned material on her own and recognition means that an external prompt, like a verbal reminder or an image, jogs the child's memory and facilitates recollection. Typically, if a child does not easily retrieve the information well, she is likely to recognize it if given a clue.
Reprinted with the permission of the NYU Child Study Center. © NYU Child Study Center.