Neuronal ceroid lipofuscinoses are a heterogenous group of genetic progressive neurodegenerative disorders. Curative therapeutic strategies are not known. These are largely diseases of childhood; adult-onset forms are rare and poorly characterized. The classical adult variant is CLN4 (Kufs' disease), in which autosomal-recessive and autosomal dominant forms are known. Furthermore the "classic infantile" CLN1, caused by a deficiency of the enzyme palmitoylprotein-thioesterase, may be of adult onset Neuronal ceroid lipofuscinoses in adulthood are multifaceted diseases. Their clinical picture is mainly characterized by progressive dementia, seizures, and extrapyramidal motor symptoms. In contrast to the infantile forms, visual loss is an uncommon feature that appears only in adult CLN1 but not CLN4, which may be helpful in clinical differential diagnosis.