Effects of hyperbaric nitrogen-induced narcosis on response-selection processes

Area of Science:

• Neuroscience
• Diving Physiology
• Cognitive Psychology

Background:

• Inert gas narcosis is a risk during underwater activities.
• Narcosis impairs sensorimotor information processing, evidenced by increased reaction time (RT).
• The specific cognitive stage affected by narcosis remains debated.

Purpose of the Study:

• To investigate if inert gas narcosis affects the response-selection stage of sensorimotor information processing.
• To determine the locus of narcosis-induced impairments in information processing.

Main Methods:

• A between-hand choice reaction time (RT) task was used.
• Ten subjects were exposed to normobaric air and hyperbaric (6 ATA) 8.33% O2 Nitrox conditions.
• Stimulus-response association rules were manipulated to target response-selection processes.

Main Results:

• The effect of manipulating stimulus-response association rules was altered by inert gas narcosis.
• Narcosis modified the performance on the RT task, indicating an impact on response selection.

Conclusions:

• Response selection processes are implicated in the effects of inert gas narcosis on sensorimotor information processing.
• This finding helps clarify the cognitive mechanisms underlying narcosis-induced impairment.