Benign familial myoclonus-like movements, partly of early onset

A family with benign, myoclonus-like involuntary movements of early onset has previously been described by us (Refsum and Sjaastad, 1972, 1973; Sjaastad, 1981). In the present communication electrographical investigations carried out in the proband and his sister will be reported. Additional information will also be reported regarding onset of the abnormal movements.