What Counts As A Learning Disability

IQ Cut-Off

Some schools limit the criterion solely to a discrepancy of 1 or more standard deviations (approximately 15+ points on a bell curve with 100 as the mean or 3+ points on a bell curve with 70 as the mean) between achievement scores and "intellectual potential" as measured by standardized tests.

For example, suppose you have a student with a verbal IQ of 100, who is thus considered to be of average intellectual potential. (This sets aside whatever you may think of IQ tests!) If that student is unable to earn a standard score of more than 70 on a standardized reading comprehension test or vocabulary or writing test (two standard deviations below the mean), that student is likely (it depends on the school) to be considered to have a learning disability.

Grade-Level Cut-Off

In other localities, there must be a difference of two grade levels or more between potential and actual performance—also as measured by standardized tests.

The same student with an IQ of 100 would be expected to be able to do grade-level work. If that student was instead reading, writing, spelling, or doing math at a level two years or more below grade level, the school would deduce the presence of a learning disability.

Inconsistent Performance

Still other schools recognize intra-test scatter as indicative of a learning disability. For example, on a standardized test of intelligence, one would expect a student with overall delayed development or mental retardation to have scores below average in all areas.

In this view, students with a learning disability may have some average scores and some below-average scores. There may be a significant discrepancy between the verbal and performance scores on an IQ test, such that the full-scale IQ is not an accurate indicator of "intellectual potential" at all. Such a student may even have a subtest score or two in the above average or superior range, some in the average range, and others below average.

Are Disabilities Increasing?

Many indicators suggest that not just the raw numbers, but the percentages of children with disabilities are increasing. The number of reported disabilities has skyrocketed. Other disorders have also gone up, such as stress disorders (depression, anxiety, trauma, and so on), autistic spectrum disorders (autism, Asperger's, and so on), and language delays.⁵⁴ This may suggest that we are getting better at identifying and reporting disabilities, or that there are simply far more of them (or quite possibly both). In 1999, students with disabilities made up 11 percent of all students between the ages of six and thirteen. There were twelve primary disability classifications, and three-fourths of the students were classified as having either learning disabilities or speech or language impairments as their primary disabilities. Another 9 percent of students were classified with mental retardation, 6 percent with emotional disturbances, and 5 percent with other health impairments.⁵⁵

Lifestyle elements are clearly connected to many disabilities. For example, environmental toxins, head injuries, and abuse all influence learning capabilities. Many investigators believe that widespread lifestyle changes like those discussed in Chapter Four may be contributing to the increase in numbers. Potential threats to brain development surround almost every child in the modern world. It is a more toxic, more stressful, more mobile, and in many ways, more scary world than ever.

Do Atypical Brains Cause Learning Differences?

How much are brains really different in children who have lower intelligence scores from those of children with average scores? What about the brains of those with disabilities? Are they different from the brains of children with no disabilities? What kinds of differences have been found in the population that has a low IQ? Remember, you can't have functional behavioral differences without some kind of corresponding change in the brain. As understanding of the causes of those differences improves, researchers will know better where to more effectively target treatments.

As background, it is essential to remember that there are learning differences among all children. Talent is the compatibility between biology and environment, and learning differences only become learning disabilities through specific environments. A given variation from the norm may be debilitating, it may be more of a nuisance and inconvenience, or it may even be an advantage.

For example, in many professions that don't require reading, dyslexia is not a disability. It makes reading very difficult, but in some cases, it can even be a gift. Being a poor reader may force one to compensate by improving other skills, but that's rare and not the real gift. Neuroscientist and child disabilities specialist Gordon Sherman believes that those with dyslexia are overrepresented in the arts, science, architecture, and entertainment. Spatial, depth, and parts-to-whole relationships seem easier to grasp for those with dyslexia.

Environmental differences are everywhere. Upbringings differ. Exposure to resources, toxins, different parenting skills, and different peers creates wide variations in brains. So we have both a genetic and an environmental influence to behaviors. These variations lead to different brains, creating different learners.

Learning, emotional, and behavioral issues are connected. Many learners who have learning disabilities get frustrated and act out when their disorders are not treated. Many who have behavioral disorders are unable to focus on the learning because of poor attention spans or inability to form positive relationships.