Altered language processing in autosomal dominant partial epilepsy with auditory features.
BACKGROUND
Autosomal dominant partial epilepsy with auditory features (ADPEAF) is an idiopathic focal epilepsy syndrome with auditory symptoms or receptive aphasia as major ictal manifestations, frequently associated with mutations in the leucine-rich, glioma inactivated 1 (LGI1) gene. Although affected subjects do not have structural abnormalities detected on routine MRI, a lateral temporal malformation was identified through high resolution MRI in one family. We attempted to replicate this finding and to assess auditory and language processing in ADPEAF using fMRI and magnetoencephalography (MEG).


METHODS
We studied 17 subjects (10 affected mutation carriers, 3 unaffected carriers, 4 noncarriers) in 7 ADPEAF families, each of which had a different LGI1 mutation. Subjects underwent high-resolution structural MRI, fMRI with an auditory description decision task (ADDT) and a tone discrimination task, and MEG. A control group comprising 26 volunteers was also included.


RESULTS
We found no evidence of structural abnormalities in any of the 17 subjects. On fMRI with ADDT, subjects with epilepsy had significantly less activation than controls. On MEG with auditory stimuli, peak 2 auditory evoked field latency was significantly delayed in affected individuals compared to controls.


CONCLUSIONS
These findings do not support the previous report of a lateral temporal malformation in autosomal dominant partial epilepsy with auditory features (ADPEAF). However, our fMRI and magnetoencephalography data suggest that individuals with ADPEAF have functional impairment in language processing.
Ottman
R
R
G.H. Sergievsky Center, Columbia University, 630 W. 168th Street, P&S Box 16, New York, NY 10032, USA. ro6@columbia.edu
Rosenberger
L
L
Bagic
A
A
Kamberakis
K
K
Ritzl
E K
EK
Wohlschlager
A M
AM
Shamim
S
S
Sato
S
S
Liew
C
C
Gaillard
W D
WD
Wiggs
E
E
Berl
M M
MM
Reeves-Tyer
P
P
Baker
E H
EH
Butman
J A
JA
Theodore
W H
WH
D000161:Acoustic Stimulation; D000328:Adult; D001303:Auditory Cortex / Q000473:pathology / Q000503:physiopathology*; D001307:Auditory Perception / Q000235:genetics*; D001931:Brain Mapping; D025063:Chromosome Disorders / Q000150:complications / Q000235:genetics; D004828:Epilepsies, Partial / Q000150:complications* / Q000235:genetics; D005260:Female; D007839:Functional Laterality / Q000235:genetics; D005799:Genes, Dominant / Q000235:genetics; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D007806:Language Disorders / Q000235:genetics / Q000473:pathology / Q000503:physiopathology*; D007807:Language Tests; D008279:Magnetic Resonance Imaging; D015225:Magnetoencephalography; D008297:Male; D009154:Mutation / Q000235:genetics; D011506:Proteins / Q000235:genetics; D011930:Reaction Time / Q000235:genetics; D013067:Speech Perception / Q000235:genetics*
D047908:Intracellular Signaling Peptides and Proteins; C116499:LGI1 protein, human; D011506:Proteins