A top-down slow breathing circuit that alleviates negative affect in mice

Area of Science:

• Neuroscience
• Respiratory Physiology
• Behavioral Neuroscience

Background:

• Breathing is largely automatic but influenced by emotions and behavior.
• Cortical control over brainstem respiratory networks is not well understood.
• Top-down regulation of respiration and its link to emotional states require further investigation.

Purpose of the Study:

• To identify and characterize a top-down neural circuit controlling breathing.
• To investigate the role of this circuit in coordinating breathing with behavior and emotional states.
• To elucidate the circuit basis for the interplay between respiration and negative affect.

Main Methods:

• Utilized a mouse model to trace neural pathways.
• Employed optogenetics to manipulate specific neuronal populations (dACC, PnC^GABA, VLM).
• Correlated neural activity with breathing patterns and anxiety-like behaviors.

Main Results:

• Identified a pathway from dorsal anterior cingulate cortex (dACC) neurons to pontine reticular nucleus GABAergic inhibitory neurons (PnC^GABA), projecting to the ventrolateral medulla (VLM).
• dACC→PnC activity correlated with slow breathing and orofacial behaviors, and was modulated by anxiety.
• Optogenetic activation of the dACC→PnC^GABA→VLM circuit slowed breathing and reduced anxiety; inhibition increased breathing rate and anxiety.

Conclusions:

• The dACC→PnC^GABA→VLM circuit is crucial for coordinating slow breathing and reducing anxiety.
• This circuit provides a neural basis for top-down control of breathing, influencing emotional states.
• Findings highlight the connection between respiratory control and emotional regulation.