EEC AND EKG OBSERVATIONS 239 



technique. For the ascent in the decompression chamber specially developed snap-on elec- 

 trodes were used. 



Compatibility with telemetery system for EKG used in Sealab n was studied, and will be 

 incorporated in the recording system. 



PROGRESS AND MATERIAL 



Neurophysiological investigations were carried out in close cooperation with Dr. Laverne 

 Johnson of the EEG Department of the Balboa Naval Hospital, where preliminary EEG tracings 

 were made from all the members of Teams 1,2, and 3. 



Dr. Scholander at Scripps Institution of Oceanography made his tanks available to one 

 team for preliminary technical testing and for calibration of the instrumentation. Additional 

 recordings were made from free-swimming scuba divers in the ocean. 



A total of 18 records was made from free-swimming scuba divers in the salt-water tanks 

 and the ocean. 



Subjects for these recordings were members from the Sealab teams, and volunteers from 

 the Scripps Institution of Oceanography - all competent divers who also gave valuable informa- 

 tion about their experiences during the tests. 



The records were made in the decompression chamber, and two records were made inside 

 Sealab n with all electrical systems and equipment turned on. This was done before the actual 

 operation started, to make sure that no artifact would be encountered from the environment. 

 Members of Dr. Sem-Jacobsen's team were subjects for these later recordings. 



Finally ten records were made in the laboratory to test out the quick recording technique 

 used for the recording of EEG in the decompression chamber during the ascent of Team 1. 



On the day of the descent into Sealab II four members of Team 1 and five members of 

 Team 2 had EEG and EKG electrodes attached to their heads and chests. Using the Vesla mini- 

 aturized unit, a preliminary EEG and EKG record was made on the staging vessel before sub- 

 mergence. To obtain the maximum number of recordings from Sealab, the Vesla unit was 

 shuttled back and forth between Sealab and the staging vessel as frequently as possible during 

 the first initial four days of the dive period for both Teams 1 and 2. 



Nine preliminary recordings were made from the members of Teams 1 and 2 on the stag- 

 ing vessel, and 18 recordings were obtained from inside Sealab 11 during the initial dive period. 



RECOMMENDATIONS FOR FUTURE STUDIES 



1. In addition to pre and post dive recording, EEG should be recorded on permanent equip- 

 ment inside Sealab. 



2. Biomedical monitoring should include EEG recordings from free-swimming divers. 

 This may easily be operational on the basis of experience from Sealab n, and with some fur- 

 ther homework in Norway during this winter. The Norwegian Navy has given free use of their 

 facilities for this work. 



