Attention deficits in tuberous sclerosis complex (TSC): rethinking the pathways to the endstate

Tuberous sclerosis complex (TSC) is a genetic disorder associated with a range of neurocognitive manifestations, including neuropsychological attention deficits most notably in dual tasking/divided attention. These dual-task deficits have so far been interpreted as evidence of a vulnerable 'cognitive module' in TSC. Here, we suggest that this interpretation represents an 'adult neuropsychological' perspective, and argue that a developmental approach would be more appropriate to examine attention deficits in TSC.

We examined the pathway to 'endstate' dual-task deficits in twenty 6-16 year olds with TSC utilising the Test of Everyday Attention for Children (TEA-Ch). We predicted that the pattern of attentional deficits in TSC would support a 'conditional' model where the establishment of a later-maturing skill was dependent on the functional maturation of an earlier expected skill.

Attentional profiles showed statistical support for a conditional model. Only one child showed a deterministic pattern while one showed a hybrid pattern, attributed to the admixture of a surgically acquired lesion and a neurodevelopmental disorder.

This preliminary study suggests that the developmental cascade in TSC may be arrested at various stages of neuropsychological development, thus leading to different developmental trajectories towards similar 'endstate' profiles.