निम्नलिखित में से कौन सा न्यूरोट्रांसमीटर अवसाद (डिप्रेशन) के पैथोफिज़ियोलॉजी से जुड़ा हुआ है?

Which digestive hormone inhibits both gastric secretion and motility, stimulates insulin release, and is secreted mainly when fat is present in the duodenum?

The repeated sequence of gradual onset of apnoea followed by gradual restoration of respiration is called ________.