Neuropsychological long-term outcome of rolandic EEG traits

Long-term outcome of rolandic epilepsy (RE) is associated with a diversity of neuropsychological deficits in childhood, although RE is historically considered as a benign epileptic disorder. Dyslexia and other developmental disorders are associated with rolandic EEG traits.

To investigate if there is an association between the manifestation of a specific EEG trait of RE and dyslexia. If the EEG traits are causing dyslexia, the cognitive deficits are supposed to be normalised after the EEG trait have resolved.

Thirty adolescents and young adults, who had previously received a diagnosis of dyslexia by standard criteria, were included. Fifteen probands (mean age = 15.9) with dyslexia and rolandic EEG traits were compared with 15 age- and sex-matched controls (mean age = 16.0) with normal EEG.

There were no statistical differences between the groups according to intelligence (Verbal IQ, Performance IQ and Arithmetical IQ) or spelling ability. However, there was a significant difference between the groups in reading ability of non-related words with the group without RE performing better than the group with RE (p < 0.01). Attentional shifts in dichotic listening with forced or directed attention are generally found in 50-60% in normative samples. However, the present date suggest an impaired attentional shift in dichotic listening test for both groups. Only one third was able to modulate their ear-preference. There were no group differences.

In general, both dyslectic groups did not show significant neuropsychological deficits as compared to standard controls. However, there were more reading errors and a tendency to attention impairments in the group with rolandic EEG trait as compared to the dyslectic group with normal EEG. Possible pathogenic factors are discussed.