Behavioral control of breathing in the cat

Area of Science:

• Neuroscience
• Respiratory Physiology

Background:

• Respiration is controlled by automatic and voluntary systems.
• The voluntary system's neural pathways and integration points remain unclear.

Purpose of the Study:

• To investigate the integration of behavioral respiratory control within the automatic system.
• To test the hypothesis that behavioral control bypasses the automatic system.

Main Methods:

• Cats were trained to control breathing patterns (apnea).
• Activity of medullary respiratory neurons was recorded using microelectrodes.
• Cellular responses during voluntary breath-holding were analyzed.

Main Results:

• Most inspiratory and expiratory neurons became inactive during voluntary apnea.
• Some expiratory neurons showed increased activity during the behavioral task.
• Neural activity patterns challenge the proposed bypass model.

Conclusions:

• Behavioral respiratory control appears to integrate within the automatic brainstem system.
• Neural integration occurs at the level of medullary respiratory neurons, not solely motor neurons.
• Findings suggest a more complex interaction between automatic and voluntary respiratory control.