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Updated: May 10, 2026
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Recording Brain Electromagnetic Activity During the Administration of the Gaseous Anesthetic Agents Xenon and Nitrous Oxide in Healthy Volunteers
Published on: January 13, 2018
The levels of processing effect under nitrogen narcosis
1Department of Psychology, University of Winchester, Winchester, United Kingdom. wendy.kneller@winchester.ac.uk
Summary
Nitrogen narcosis impairs memory encoding during deep dives, but deeper processing of information can mitigate these effects. This research clarifies how narcosis impacts divers' memory.
Area of Science:
- Human Physiology
- Cognitive Psychology
- Marine Biology
Background:
- Inert gas narcosis, commonly nitrogen narcosis, affects diver memory.
- Previous studies indicate narcosis impacts free recall more than recognition memory.
- A potential cause is narcosis interfering with memory encoding.
Purpose of the Study:
- To test the hypothesis that narcosis affects memory encoding.
- To investigate the influence of processing depth on free recall under narcosis.
- To differentiate between encoding and retrieval deficits caused by narcosis.
Main Methods:
- Experiment 1: 67 divers experienced free recall tasks at two depths (0-2 msw and 37-39 msw) with shallow and deep processing levels.
- Experiment 2: Controlled for environmental differences between depth conditions.
- Statistical analysis included age as a covariate.
Main Results:
- Divers under narcosis (deeper water) exhibited significantly worse recall than those in shallow water.
- Deeper levels of processing consistently improved recall in both shallow and deep water conditions.
- Experiment 2 confirmed the findings were not due to environmental factors.
Conclusions:
- Memory performance under narcosis is influenced by the depth of information processing.
- Findings support the theory that narcosis primarily impairs the encoding stage of memory.
- Narcosis appears to affect memory encoding rather than retrieval processes.
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