Executive function and general intellectual function in dyskinetic cerebral palsy: Comparison with spastic cerebral palsy and typically developing controls

Commentary by Christelle Nel, Trainee in neurodevelopment , University of Pretoria

The aim of this study from Spain was to describe intellectual and executive function in people with dyskinetic cerebral palsy (DCP), by comparing their performance with that of: 1) typically developing controls (TDC) matched for age and sex, and 2) participants with spastic cerebral palsy (SCP) matched for age, sex, term/preterm and gross motor function classification system (GMFCS).

The article reports on several previous studies assessing the association between spasticity/dyskinesia and cognition, however comparison between studies are difficult as different measures of assessing cognition in participants were used and other important variables such as motor severity and prematurity were not considered in all the studies. Results are therefore conflicting.

Results of this study showed that both CP groups had lower intelligence than TDC and performed poorer in almost all executive function tasks. Intelligence was higher in DCP than SCP (z = -2.51, p=0.01). Participants with DCP also performed significantly better in goal – setting tasks (z = 2.27, p=0.03) and information processing (z = -2.45, p= 0.01) than those with SCP.

The authors conclude that although their results might not be representative of the general CP population for both SCP and DCP, it does indicate that cognitive function may be underestimated in DCP and observations made in SCP can’t be generalized to dyskinetic forms. Proper assessment of cognitive function in various CP sub-types is important for prognosis and appropriate educational support.