         Sentence 1: What's the difference between working|  all night until 4am and waking up at 12pm and going]  to sleep at 10pm and waking up to work at Sam?    Sentence 2: Being an ‘owl’, | usually go to sleep at|  Tpm-tam, but very rarely, | wake up early (e.g. 5am}  and feel kind of a euphoria and rise of productivity,  which lasts until afternoon. Is there any medical]  reason for that euphoria?    