The University of British Columbia
The human brain needs tightly controlled blood flow. Too much or too little blood can cause serious problems, including a condition known as Cheyne-Stokes respiration that makes breathing regulation unstable. The condition is most pronounced among individuals with traumatic brain injuries and sometimes occurs with aging, especially in those with heart disease and strokes. Curiously, it also occurs in almost all healthy people during sleep at high altitudes.
To better understand how the body controls breathing and the crucial flow of blood to the brain, University of British Columbia doctoral student Christopher Willie is studying why healthy people develop Cheyne-Stokes respiration at high altitudes. The recipient of the doctoral level 2011 NSERC André Hamer Postgraduate Prize, Willie will conduct two studies to test preliminary theories suggesting breathing irregularities are due to changes in cerebrovascular sensitivity to carbon dioxide and/or reduced cerebral blood flow.
The first study will induce increased and decreased cerebral blood flow in human subjects at sea level and high altitude. In the second study, nine healthy people living in a controlled laboratory 4,000 metres above sea level will be examined for regulatory changes in blood flow to the brain and breathing over a four-month period. The results of the tests will help answer basic questions about human physiology that are essential to prevent and treat age–and disease–associated declines in brain function and diseases that affect breathing.