Neurocognitive and psychosocial functions in children with frontal and temporal lobe epilepsy

A key construct at the foundation of cognitive and clinical developmental neuropsychology is the notion that cognitive functions are localized to specific cortical regions in the brain. Consistent with this, relatively stable cognitive and behavioral profiles have been described for adults diagnosed with the two most common focal-onset seizure disorders. Temporal lobe epilepsy (TLE) is primarily associated with impairments in memory functioning (Bell & Giovagnoli, 2007) and frontal lobe epilepsy (FLE) with impairments in executive and motor functioning (Patrikelis et al., 2009). However, the immature brain may be particularly vulnerable to the adverse effects of recurrent seizure activity, showing more widespread effects on cognitive processes and brain organization compared to adults (Korman et al., 2013). Despite these observations, few studies have directly compared performance between children with different epilepsy syndromes utilizing broad assessments spanning multiple domains (Williams, Griebel & Dykman, 1998). Consequently, the aim of this study was to evaluate the degree and selectivity of patterns of cognitive and psychosocial dysfunction in children with TLE and FLE.

Participants included 51 children between the ages of 6 and 16 years with intractable epilepsy who were consecutively seen for a neuropsychological evaluation through the Dell Children’s Medical Center Comprehensive Epilepsy Program. During this assessment, participants were administered a battery including measures of memory, executive, motor and intellectual functioning. In addition, parents completed questionnaires regarding their child's behavioral and psychosocial functioning. Contrary to the selective patterns of deficits typically described in adults, both the TLE and FLE groups demonstrated significant impairments relative to normative values on each of the domains assessed. Moreover, no significant differences were found between the two patient groups on any of the measures, with the exception of a task of visual memory.

These findings suggest that individuals with childhood-onset epilepsy exhibit fairly broad patterns of cognitive compromise that do not differ significantly with frontal lobe versus temporal lobe seizure localization. Furthermore, the range of deficits observed would not normally be expected with analogous seizure disorders acquired in adulthood. These results provide important insights into the organization of cognitive and behavioral functions following early neurological insults associated with epilepsy.