The release of endogenous opioids in 5 patients with reading-induced seizures was investigated using C-diprenorphine PET scans at the MRC Cyclotron Unit Hammersmith Hospital, and the Institute of Neurology, London, UK. During reading a scientific paper, opioid-receptor binding in the left parieto-temporo-occipital cortex (Brodmann area 37) was increased in control patients and decreased in those with reading epilepsy. Opioid-like substances may be involved in the termination of reading-induced seizures. 
COMMENT. This novel PET approach to the measurement of neurotransmitter changes associated with focal seizure activity during reading-induced seizures provides further information regarding the anatomical localization of a specific learning disability.