Significant differences on the LNNB-CR were found to exist between preoperational and concrete operational groups. The preoperational group scored in the brain-damaged range even though all subjects were screened to eliminate those with any indicator of brain injury. Results indicate that the LNNB-CR is overly sensitive to brain damage. The biasing variable appears to be neuropsychological development as reflected by cognitive level of functioning. A relationship was found to exist between Luria's stages of neurological development and Piaget's levels of cognitive development.

Differences in neuropsychological functioning in eleven areas (motor skills, rhythm, tactile, visual, receptive speech, expressive language, writing, reading, arithmetic, memory, and intelligence) were measured in order to determine the influence of cognitive levels of development (preoperational, transitional, and concrete operational). The Luria-Nebraska Neuropsychological Battery-Children's Revision (LNNB-CR) (Golden, 1980a) was used to measure neuropsychological development and functioning. The LNNB-CR, developed by Golden, is based on Luria's theory (1973 and 1980) of neurological development. The Concept Assessment Kit-Conservation (CAK-C) (Goldschmid and Bentler, 1968), based on Piaget's developmental model, was used to determine cognitive developmental level. A total of 30 subjects were assigned to three groups according to developmental level. Analysis of variance was used to determine differences in neuropsychological results between groups.