Spinal Unit Activity During Synchronization of a Convulsive Type (Strychnine Tetanus)

¹ From the Department of Anatomy, University of California, Los Angeles, and Medical Research Programs, Veterans Administration Hospital, Long Beach, California

Single unit activity during convulsive synchronized discharge and the relationship between unit activity and slow ‘waves’ were studied in the spinal cord of the decerebrate cat after intravenous injection of strychnine. Steel needle microelectrodes were used. Units did discharge in burst (from 1 to 5 impulses) only in coincidence with the slow oscillatory potential (tetanic ‘waves’). The firing is confined to the rising phase of this potential. Changes in d.c. state related to a convulsive activity were also studied. A relationship was found between frequency of the tetanic rhythm and d.c. state of spinal structures. The mechanisms of synchronization and rhythmicity of the convulsive activity in a population of neurons are discussed in connection with the problem of interaction between units.