Self-regulation of cerebral blood flow by means of transcranial doppler sonography biofeedback

Abstract

Background: Transcranial Doppler sonography (TCD) allows the continuous non-invasive assessment of intracranial blood flow velocities with high temporal resolution. It may therefore prove suitable for biofeedback of cerebral perfusion. Purpose: The study explored whether healthy individuals can successfully be trained in self-regulation of cerebral blood flow using TCD biofeedback. Methods: Twenty-two subjects received visual feedback of flow velocities in the middle cerebral arteries of both hemispheres. They were randomly assigned to two groups, one of which attempted to increase, the other to decrease the signal within eight training sessions. Heart rate and respiratory frequency were also monitored. Results: Both groups achieved significant changes in flow velocities in the expected directions. Modulations in heart rate and respiratory frequency during biofeedback did not account for these effects. Conclusions: TCD biofeedback enables efficient self-regulation of cerebral blood flow. It is promising in applications such as the treatment of migraine and post-stroke rehabilitation. © The Society of Behavioral Medicine 2010.