In preparation for an appraisal of the possible effect of strong magnetic field on cerebral function electroencephalograms of squirrel monkeys subjected to strong homogeneous and gradient fields (up to 91,250 oersted) were measured. Higher than normal amplitudes and frequencies were found in the recordings from exposed animals. The unusual EEG records are discussed and an attempt is made to explain the observation. The study is part of a plan to investigate interaction of magnetic fields with the nervous system in general. (Author).

In the future, strong magnetic fields will play a greater role in the environment of man. In preparation for this the frontal plane ECG of subhuman primates in strong magnetic fields (100,000 oersted) was recorded. A pulsating electrical signal (flowgram) was found superimposed on the ECG, giving information on mechanical as well as electrical performance of the heart. No influence of the magnetic field on cardiac regulation was observed during short exposure periods. (Author).

Action potentials were recorded at four positions from frog sciatic nerves exposed to a constant magnetic field of 11.6 kilo-oersted. External electrodes arranged in pairs on segments of nerve oriented both parallel and perpendicular to the field permitted conduction velocity measurements to be expressed as a function of field orientation. An increase in conduction velocity was observed to be orientation dependent as was a latent period in its appearance. An aftereffect was noted that persisted to the end of the experiments. Possible mechanisms of action of the field are discussed in terms of current theories of impulse propagation. (Author).