NCL type 1; Batten's disease; a form of lysosomal storage disease with onset between the ages of 5 and 15 years; abnormal auotofluorescent lipopigments are present in fingerprint cytosomes within nervous system tissues and other organs; inheritance usually autosomal recessive; early symptoms include behavioral changes, visual dysfunction, and learning difficulty; symptoms progress to dementia and blindness, with the addition of seizures, myoclonus, and motor dysfunction (pyramidal and extrapyramidal); reduced or absent electroretinogram; MRI may show cortical atrophy; diagnosis is made by light and electron microscopic examination of tissue specimens and by enzyme and mutation testing; no specific treatment is available; anticonvulsant therapy and supportive care.