Neuropsychiatric Symptoms of Epilepsy

13 Attention, Executive Function, and Attention Deficit Hyperactivity Disorder
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could include age of onset, duration or severity of seizures, seizure type or locus, or
epileptiform discharge on EEG. Antiepileptic drugs may have a negative impact on
attention and executive functioning, or, alternatively, might be beneficial. The
occurrence of ADHD is not secondary to psychosocial stressors, but severity of
ADHD symptoms has been related to adverse circumstances of life. Epilepsy may
be an additional stress that contributes to severity of ADHD or executive
dysfunction.
Age of onset of seizures has been associated with cognitive problems but not
emotional difficulties. Though it might be expected that early onset of seizures
might negatively impact development of attention networks, age of onset has not
been consistently associated with problems of attention or executive function in
people with epilepsy. Tsai et al. [ 79 ] and Tanabe et al. [ 42 ] found an association
between early age of onset and problems with attention. Black et al. [ 80 ] and
Campiglia et al. [ 58 ] noted an association of early age of onset with executive function
impairment. However, other studies have found no association with age of
onset [ 37 , 81 ]. This may be partially due to sample characteristics. Hermann et al.
[ 37 ] assessed children with new-onset seizures starting after 8 years of age, and
Cerminara et al [ 81 ] restricted their sample to children with BECTS, which typically
starts after 3–4 years of age.
Duration of epilepsy, frequency of seizures, and severity of epilepsy may contribute
to difficulties with attention and executive function. The prevalence of
ADHD was highest in children with severe epilepsies and lowest in a sample that
followed children after remission of seizures [ 44 , 45 ]. In children with childhood
onset absence epilepsy, Caplan et al. [ 40 ] found an association of ADHD with duration
and frequency of absence seizures. Vega et al. [ 82 ] found that children with
uncontrolled absence seizures were more impatient than those with controlled seizures,
and Masur et al. [ 83 ] noted more attention difficulties in those children that
continued to have absence seizures in spite of AED treatment. In the initial evaluation
of childhood absence epilepsy, future attention problems were associated with
duration of seizures but not seizure frequency on initial EEG.
The association of seizure type and focus of epileptiform discharge with attention
and executive function has been assessed. Hernandez et al. [ 84 ] showed that
children with frontal lobe epilepsy had more attention problems than those with
temporal or generalized seizures, and Gottlieb et al. [ 85 ] found more impairment of
executive function in children with frontal lobe seizures than in those with temporal
lobe foci. In contrast, Dunn et al. [ 34 ], Hermann et al. [ 37 ], Jones et al. [ 39 ], and
Almace et al. [ 86 ] found no association between seizure type or localization and
attention/executive functioning, and Jackson et al. [ 87 ] found more executive function
difficulties in children with idiopathic generalized than in those with idiopathic
focal epilepsy. Hoie et al. [ 88 ] noted no problems with executive function in children
with benign focal seizures, although it would seem likely that frontal lobe
dysfunction would lead to inattention or executive function impairment.
Epileptiform discharges may be important in attention and executive function. In
a study combining video-EEG with neuropsychological function, frequent nonconvulsive
seizures were associated with attention and cognitive impairment [ 89 ].