For some people, rising from bed or completing daily tasks can feel like extricating oneself from quicksand or the grip of a coiling anaconda. Those with chronic fatigue syndrome, sometimes known as myalgic encephalomyelitis (CFS/ME), suffer from symptoms like extreme and persistent exhaustion and cognitive issues, including 'brain fog'. CFS/ME is an 'unambiguously biological' condition for which there is no known cause or cure.