Features of reading-induced seizures:
(1) reading results in jaw myoclonus, with a clicking sensation and/or movement in the jaw
(2) the subsequent course depends on whether or not reading continues
(2a) if the patient continues to read then the patient can develop a generalized convulsion;
(2b) if reading is stopped then no convulsion occurs
Onset is usually during puberty (range 11 to 22 years).
Males are affected more often than females in a ratio of 2 to 1.
Types:
(1) primary: The only type of seizure experienced by the patient is reading-induced.
(2) secondary: The patient experiences other types of seizures.
Variations:
(1) For some patients there is a family history of the disorder.
(2) For some patients the jaw myoclonus can be induced by other triggers in addition to reading: light, television, talking, writing, arithmetic and decision-making.
(3) Some patients may have upper limb involvement in addition to the jaw myoclonus.
(4) Some patients have a greater problem when reading aloud.
An EEG recorded during the reading-induced jaw clicking will show 3 to 6 Hz synchronous, bilateral discharges that are maximal over the parietal and occipital regions.