High field fMRI:
The Institute of Neuroscience at Newcastle University has a multichannel high-field structural and functional brain imaging unit (funded by the Wellcome Trust and SRIFII). The facility is equipped with a 4.7T Bruker scanner, to study the neural basis of the BOLD signal, investigate sensory and cognitive processing in the primate brain, and investigate the role of network interactions in mediating perceptual processes. In addition, we have strong links to the recently established human research and clinical fMRI Centre.
We investigate how the fMRI signal reflects the underlying information processing function mediated by neuronal activity. While sensory information in cerebral cortex is represented as a temporal pattern of action potentials distributed across large neuronal populations, the fMRI signal, due to its vascular nature, will only be able to provide a coarse spatial and temporal filtering of this neuronal information. Using a combination of neuronal and hemodynamic mathematical modelling and of neurophysiological recordings we characterize the relationship between various aspects of the fMRI signal (such as its strength, its time course, the spatial resolution used) and neuronal coding.
Our current work focusses on visual and auditory scene analysis, on attentional mechanisms, and on network interactions and their susceptibility to disturbance, whereby we compare single cell, local field potential and fMRI BOLD activity, and how they reflect inhibitory and facilitatory mechanisms.
In collaboration with Auditory Group Clinical Laboratory (e.g. Prof. T.D. Griffith and Dr. A. Rees) we investigate auditory stimulus representation in the cortex by using high field fMRI.