Neurodevelopmental and behavioural characteristics in learning disabilities and attention deficit disorder.

Specific learning disability in childhood is frequently associated with attention deficit disorder. The distinction between children with and without such comorbidity is often difficult to make. Our aim was to delineate the neurocognitive and behavioural differences between children with specific learning disabilities, with and without attention deficit. Students diagnosed with learning disability, mean age 8.3, 1.4 SD (N-50), and students with learning disability and attention deficit disorder, mean age 8.7, 1.4 SD (N-50), were assessed. The Paediatric Early Elementary Examination and the Aggregate Neurobehavioural Student Health Education Review were administered and their scores as well as pattern of correlations within and between domains were analysed. Only few differences in neurocognitive functions between these groups were evident. Most neurocognitive domains were similarly intercorrelated in the two groups. However, recall was correlated with other neurocognitive domains only among the children with learning and attention deficits. A proportion of significant correlations between neurocognitive and behavioural domains was found among the children with learning disability and attention deficit disorder, but not among the children with learning disability only. It appears that while neurocognitive profiles are similar in these two groups, their interrelationship with behavioural patterns differ. These findings give support to the neurological origin of attention deficit disorder related behaviours among learning disabled children. Different interventions should therefore be considered for each of these entities.