Nonverbal learning disabilities: A critical review

Abstract

This article presents a critical review of the term and concept of nonverbal learning disability (NLD). After a brief historical introduction, the article focuses on the apparent rarity of NLD; the hypothesis of the frequent co-occurrence of emotional disorder, depression, and suicide in NLD; the white matter hypothesis as an explanation of the origin of NLD; and the question of NLD as part of a variety of other disorders. It is argued that NLD presents a broad hypothesis, but that there is little evidence to support its use in clinical practice.

Keywords:

• Nonverbal
• Learning
• Disabilities
• Review
• Critique

Notes

¹This amounts to 3.2% of the sample. The authors list it as 4%; a number of children were excluded from the analysis because of missing data or lack of agreement among the multidisciplinary team.

²This prediction is apparently contradicted by a later study (Tsatsanis, Fuerst, & Rourke, 1997) that found “no increase in psychopathology with advancing age” (p. 490). Another paper (Rourke, 1988a) confirms this for learning disabilities, in general, but insists that “psychopathology worsens in children with NLD” (p. 801). Finally, Ralston, Fuerst, and Rourke (2003) examined one hundred and one 7- to 15-year-old children with below average IQ and found “no changes in psychopathological severity or type with advancing age” (p. 269).

³A somewhat similar theory had been advanced by Bogen and Bogen (1969), namely that the two hemispheres are capable of independent and somewhat different forms of information processing; that having two independent processors is advantageous to problem solving, and that for these two processors being able to function there must be a corpus callosum available for hemispheric interaction.

⁴Rourke's 1993 paper also lists hydrocephalus, myelomeningocele, Williams syndrome, Cornelia de Lange syndrome, early shunted hydrocephalus, Spina bifida, Chiari II Malformation leukodystrophy, autism, and exposure to cranial irradiation, Fragile X syndrome, especially high-functioning 46 XX, del (17; p12p13.1), Triple-X syndrome, Sotos syndrome, Periventricular leucomalacia (PVL), ;abuki syndrome, prophylactic treatment for acute lymphocytic leukemia (@ other cancers), metachromatic leucodystrophy (early in disease progression), congenital hypothyroidism, fetal alcohol syndrome (high functioning), traumatic brain injury (diffuse white matter perturbations), toxicant-induced encephalopathy and teratology, children with HIV and significant white matter pathology, Haemophilus influenza meningitis, early-treated phenylketonuria, intraventricular hemorrhage (early), children with cardiac disease, children with low birth weight (<1500 g), congenital adrenal hyperplasia, insulin-dependent diabetes mellitus, Noonan syndrome, Fahrs syndrome.

⁵In addition, Rourke (1995, p. 486) lists six other syndromes as being “ambiguous” or “similar (but basically different).” One objection to this long list of “similar to NLD” disorders is stated by Dennis (personal communication, 2009): “The NLD umbrella includes practically every pediatric disorder, many of which have diametrically opposed features. Conditions like spina bifida and Asperger's Disorder, both supposedly NLD, have completely different cognitive phenotypes. Another objection to the “syndrome of NLD” is the definition: A syndrome in the traditional sense refers to a unique set of symptoms specific to a particular illness. To find part of the syndrome in other, well-defined disorders does not make logical sense.”