Dr. Bindu Paul of Johns Hopkins University discusses remarkable discoveries which showed that three ‘toxic’ gases – nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S) – are produced in brain cells. Their production occurs in response to activity in neuronal networks and evidence suggests that each of these gases plays important roles in learning and memory, and the regulation of blood flow in the brain. Diet and lifestyle factors, and drugs can affect the production of the ‘gasotransmitters’ in ways that improve brain health. Abnormalities in the regulation of these gases is believed to occur in Alzheimer’s and Huntington’s diseases, and chronic fatigue syndrome.