The NVLD Misdiagnosis

Or, Why the Label May Be Getting It Wrong

Many children today with neuropsychological profiles very similar to Susan’s are diagnosed with a Nonverbal Learning Disability (NVLD). The diagnosis was propounded and championed in the research literature by proponents who believed that a certain constellation of cognitive deficits was caused by a problem in the right side of the brain—the side generally believed to be responsible for nonverbal processing, as opposed to the left side, where language usually resides. The evidence for attributing these deficits to right-brain dysfunction was slim, resting on brain images from a very small number of people, a number of whom had experienced a traumatic injury to the right side of the head.

In the years since, brain imaging has identified one characteristic of NVLD children, and it is not a right-brain anomaly. It is a significantly smaller splenium—a part of the corpus callosum, which connects the right and left hemispheres. Susan’s brain images do not appear to show that.

People now understand NVLD to be primarily a visual-spatial processing problem, often accompanied by dyscalculia (difficulty with arithmetic) and dysgraphia (difficulty writing by hand—poor penmanship, difficulty coloring neatly). Susan has profound difficulties in all those areas. But, and this is the important point, her brain images all show that it is the left side of her brain that is far more impaired than the right, with few healthy neuronal connections.

Indeed, the reason we call people like Susan GPS folks—Global Positioning Syndrome—stems in part from skepticism about the NVLD diagnosis, a label for which many plead to be included in each new version of the DSM (Diagnostic and Statistical Manual of Mental Disorders). That plea is understandable, because funding for special education and other accommodations generally rests on a diagnosis included in that manual. You can read more about GPS in the FAQ section of this site.

Despite that, we believe that the prevailing understanding of people with GPS, and thus many of the regularly prescribed interventions, may do more harm than good. For example, people now classified as NVLD often start out as proficient readers, but after beginning school their reading abilities plummet. Susan started school as an advanced reader, was told she was doing it all wrong, and had she deferred to her teachers—who insisted on reading phonetically, letter by letter—her reading comprehension would have fallen precipitously, as happens to many NVLD children. The literature characterizes that drop as a feature of NVLD, when it may well be a consequence of draining meaning from a text by requiring the child to concentrate on details instead of the whole picture.

Details, we are told, are the problem with NVLD children: they cannot see the whole. Susan always grasps the whole faster than others—but not when forced to concentrate on the pieces first.

Finally, the NVLD literature largely fails to grapple with Gerstmann’s syndrome, which occurs when the left angular gyrus of the brain is injured and produces dysgraphia, dyscalculia, left-right disorientation, and finger agnosia—which often manifests as clumsiness with one’s hands, such as dropping objects or having a weak grip.

After a two-day battery of neuropsychological tests at Massachusetts General Hospital in 2005—the first such testing Susan had ever undergone; she was 50—the diagnosis was Gerstmann’s syndrome, despite the fact that Developmental Gerstmann’s Syndrome (as opposed to Gerstmann’s through trauma) had long been out of fashion as a diagnosis. NVLD was well established by then, but Susan was a law professor, and the notion of her not understanding text—of being unable to see the forest for the trees—made a diagnosis of NVLD blatantly absurd. Had she been a child, however, we believe the label of NVLD would have been applied, and she would not have gone on to Yale Law School or become a distinguished scholar.