Autopsy of a patient with mild dementia associated with an emotional disorder characterized by paroxysmal rage and excitement during the clinical course revealed massive argyrophilic grains in the subicular, entorhinal and amygdaloid regions, and to a lesser extent in other limbic areas as well. A few argyrophilic coiled bodies were also found in the subcortical white matter in the same area as the cortical argyrophilic grains. These pathological findings are consistent with a type of cytoskeletal abnormality referred to as 'argyrophilic grain dementia', which some authors describe as a new type of progressive dementia. Immunohistochemically, the grains reacted with anti-human-tau, and in part with anti-ubiquitin antibodies. Immunoelectron microscopic examination revealed the grains to consist of tubulo-vesicular structures within processes, but it was impossible to identify their origin. The neuropathologic substrate of this peculiar case of dementia was thought to be the grains in the limbic area. The detailed clinical picture and distribution of the grains are described to contribute to further discussion.