Final answer:
The ventral respiratory group (VRG) is believed to control breathing rhythm by stimulating the contraction of accessory muscles involved in respiration to induce forced inspiration and expiration.
Step-by-step explanation:
The ventral respiratory group (VRG) is believed to control breathing rhythm. It is a region of the medulla oblongata, which is part of the brainstem. The VRG stimulates the contraction of accessory muscles involved in respiration to induce forced inspiration and expiration. This helps in regulating and maintaining a consistent breathing rhythm.