We used positron emission tomography to measure hippocampal and medial temporal 
lobe metabolism in brains of patients intoxicated by domoic acid from Prince 
Edward Island mussels. This analog of kainic acid specifically excites certain 
neurons in the hippocampus, and the study revealed a severe reduction of glucose 
metabolism in this part of the brain which paralleled the absence of long-, 
medium-, or short-term memory in these patients.