Non-invasive methods to investigate brain function in health and disease

Abstract

Non-invasive methods to investigate brain function have been used in research laboratories for many decades, however their popularity has increased in recent years given the ease of use and broad application. Such methods have proved valuable in improving our knowledge about numerous areas of basic brain function. Many non-invasive techniques have also been applied to patient groups to allow further identification of pathological mechanisms, but critically a new role has been found for some as biomarkers of disease. Neurodegenerative disease is fast becoming one of the biggest medical problems in the first world. An aging population has caused the relative incidence of many conditions to rise dramatically and studies suggest that this trend will continue. Although our knowledge surrounding these conditions has improved significantly, most remain notoriously difficult to diagnose and to treat. The recent introduction of neuroprotective drugs offers the potential to slow the progression of some diseases. However, to take full advantage of these disease-modifying treatments, administration must occur early in the disease course which fuels the demand for selective and specific diagnostic tests. There is currently a great need to enhance the clinical diagnostic repertoire with reliable, robust and specific biomarkers of neurodegenerative disease. However, careful, rigorous studies are required to validate the use of non-invasive techniques in this role. The same level of care should also be applied to techniques used in basic research; without a fundamental understanding of the mechanisms underpinning these techniques, their utility in the investigation of specific processes or pathways is questionable. This thesis aims to address specific cases to evaluate existing techniques and to screen potential new disease biomarkers.