Cognitive deficits in children with gelastic seizures and hypothalamic hamartoma

To characterize the cognitive deficits in children with gelastic seizures and hypothalamic hamartoma and investigate the relationship of seizure severity to cognitive abilities.

Eight children with gelastic seizures and hypothalamic hamartoma completed a neuropsychological battery of standardized and age-normed tests, including the Woodcock-Johnson Psycho-Educational Battery-Revised: Tests of Cognitive Ability, Peabody Picture Vocabulary Test-III, and initial-letter word fluency measure.

All children displayed cognitive deficits, ranging from mild to severe. Gelastic/complex partial seizure severity was correlated with broad cognitive ability standard scores (r = -0.79; r2 = 0.63; (F[1,6] = 10.28; p = 0.018]. Frequency of gelastic/complex partial seizures was also correlated with broad cognitive ability standard scores (r = -0.72; r2 = 0.52; F[1,6] = 6.44; p = 0.044). Significant intracognitive standard score differences were found, with relative weaknesses in long-term retrieval (mean = 64.1; SD = 13.3) and processing speed (mean = 67.7; SD = 21.6) and a relative strength in visual processing (mean = 97.6; SD = 12.8). Performance in visual processing differed from performance in long-term retrieval (p = 0.009) and processing speed (p = 0.029).

These findings are consistent with cognitive functions and affective/emotional states associated with conduction pathways of the hypothalamus involving cortical association areas and amygdala and hippocampal formation. These abnormalities can account for the prominent deficit found in integrating information in the processing of memories.