<P> Retroperistalsis is the reverse of the involuntary smooth muscle contractions of peristalsis . It usually occurs as a precursor to vomiting . Local irritation of the stomach , such as bacteria or food poisoning , activates the emetic center of the brain which in turn signals an imminent vomiting reflex . Food then moves in the opposite direction , often from the duodenum into the stomach . </P>
<P> Retroperistalsis is the reverse of the involuntary smooth muscle contractions of peristalsis . It usually occurs as a precursor to vomiting . Local irritation of the stomach , such as bacteria or food poisoning , activates the emetic center of the brain which in turn signals an imminent vomiting reflex . Food then moves in the opposite direction , often from the duodenum into the stomach . </P>
antiperistalsis is controlled by which part of brain
antiperistalsis is controlled by which part of brain
the emetic center of the brain
the emetic center of the brain