Cognitive Functioning of Children with Phenylketonuria (Learning Disabilities).

Abstract

A descriptive study of the cognitive performance characteristics of thirty-three early-treated, diet-terminated children with phenylketonuria (PKU) was conducted. The subjects, aged six through seventeen years, were administered a psychoeducational battery designed to assess their patterns of cognitive strengths and weaknesses. In addition, behavior ratings of these children were completed by parents and teachers, and school records were obtained. Results indicate that many of these children exhibit residual effects of PKU that are manifest in learning problems and in behaviors associated with learning disabilities. While academic success in this sample relates to IQ scores, the risk for learning dysfunction among these children is apparent across ability levels. The most pervasive areas of achievement deficit include mathematics and written language. Significant deficits in auditory short-term memory and in visual-motor integration are demonstrated by over half of the children. In addition to specific areas of cognitive dysfunction many children is this sample, particularly those children with low-average IQ scores, exhibit behaviors which are frequently observed among children with diagnosed learning disabilities--inattentive or passive behaviors, impulsive and /or hyperactive behaviors, and conduct problems. For this sample of PKU children a specific group profile of learning characteristics does not emerge. Rather, the cognitive performance pattern varies within the sample, and any CNS reaction that is manifested as learning dysfunction is idiosyncratic to the child. Children with PKU, even those with average intellectual abilities, may be at risk for learning and behavior problems which may negatively affect academic success.