CNS & plasticity: sleep, juggling and pain

In neuroscience, next to „functional imaging„ some innovative new imaging techniques based on structural attributes have begun to be established and their potential recognized. Using the high spatial resolution of three-dimensional structural MRI-datasets, transformed into a common stereotactic space, morphometric techniques such as voxel-based (VBM) and deformation based analysis (VBM) are designed to seek significant regional differences by applying voxel-wise statistics in the context of Gaussian random fields. VBM is fully automated, unbiased, and has been cross-validated with region-of-interest measurements and functional data in a number of studies. VBM demonstrated in the past two years, that it is observer- independently capable of revealing subtle changes in grey matter volume/density by averaging across subjects. This technique establishes a 'lesion' in the brain that can not be detected by conventional MRI and may allow extremely subtle anatomical traits to be imaged and localised pointing the way to future neuropathological examination. In „idiopathic“ syndromes VBM has proven to be a powerful method to detect regional differences in cerebral structures in a variety of diseases like narcolepsy and restless legs syndrome, cluster headache and migraine, parkinsonian tremor, Huntington duisease and schizophrenia to name a few. Particularly for cluster headache it is remarkable, that findings in functional imaging and VBM have been directly translated into a successful therapeutical approach, i.e. deep brain stimualtion of the hypothalamus. Additionally, recent data regarding learning point towards the fundamental capability of the adult human cortex to adapt and change structurally in response to changes in the enviroment. This competence on a physiological level is crucial in our understanding of specific findings in so called idiopathic diseases. However, it is still one of the most interesting questions, whether those structural changes are primary or secondary to the syndrome. Only if we understand what exactly happens on a macroscopic and microscopic level, will we be in a position to use and translate our knowledge regarding plasticity into new treatment options. This will be extremely interesting with respect to progressive diseases such as dementia and chronic pain.