Summary:Nonconvulsive seizures were divided into the two major classes used in the International Classification of Seizures (partial and generalized). Of the patients with nonconvulsive seizures reported, four had complex partial seizures and two had generalized absences. An analysis of the simultaneous recordings of EEG activity and the behavior of patients with nonconvulsive seizures on closed circuit television (CCTV) led to improved recognition and management of the seizures by providing information essential for making proper diagnoses and classification. Some anatomical and physiological factors are offered to explain the limited ability of scalp EEG to register epileptogenic spike activity occurring at the cortex.