What’s causing this patient’s spontaneous laughter?

A four-year-old girl is referred to a pediatric neurologist with new-onset generalized tonic-clonic seizures. Her father mentions that she has also had sudden episodes of spontaneous unexplained loud laughter for the past year, and they now occur almost daily. Neurological examination is unremarkable. An MRI reveals the findings seen here. Which of the following other clinical features is commonly associated with this patient’s condition?

A. Short-term memory impairment
B. Sleep disturbance
C. Precocious puberty
D. Weight gain

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