Dear Users

Today (4-5 pm in YNiC) there will be a talk by Dr Aneurin Kennerley from the University of Sheffield.

http://www.sheffield.ac.uk/psychology/staff/research/aneurin-kennerley

The title of Dr Kennerley's talk is "Concurrent 7T fMRI and 2-D Optical Imaging Spectroscopy: Towards building a forward model between neuronal activity and the BOLD signal". Please see below for the talk abstract.

Everyone is welcome to attend and refreshments will be provided after the talk.

Best wishes Rebecca

Abstract: Functional magnetic resonance imaging (fMRI) has become the cornerstone of cognitive neuroscience in recent years. The widely used Blood Oxygenation Level Dependent (BOLD) signal is often used to interpret changes in neuronal activation. However, at present, a biophysical understanding of the neurovascular drivers of the BOLD signal is not clear and thus hinders any quantitative estimation of the underlying neuronal activity.

Neuroimaging research at the University of Sheffield drives towards building a forward biophysical model of this complex relationship. As part of this multidisciplinary group my research is aimed at developing a general model of the BOLD signal which can model both intra- and extra- vascular MR signals, across a wide range of imaging parameters, from estimates of the haemodynamic changes.

Validation and refinement of the haemodynamic response models underlying fMRI signals, an essential precondition for the correct interpretation of human BOLD data requires invasive multimodal animal imaging. I have developed an innovative in-vivo methodology for concurrent fMRI and 2D optical imaging spectroscopy (2D-OIS) techniques for simultaneous measurement of BOLD signal and underlying haemoglobin changes to neuronal activation in the healthy rodent model.

Applications of this technology include: 1) Understanding of the negative BOLD signal (Boorman et al 2010). Most researchers assume a negative BOLD to be a result of either neuronal inhibition or vascular steal. It is only with the simultaneous, independent measurement of haemoglobin changes (with 2D-OIS) that one could disassociate any possible physiological relationships; 2) Refinement of mathematical and biophysical models of both the BOLD signal and optical imaging spectroscopy techniques (Kennerley et.al. 2009); 3) Calibration of non-BOLD fMRI techniques such as VASO and ASL; 4) Interpretation of abnormal BOLD responses; specifically in disease and trauma conditions in which either neuronal or haemodynamic breakdown could be responsible.

[1] Boorman, L.W. et.al. (2010) /Journal of Neuroscience/. /30(12): 4285-94;/ [2] Kennerley, A.J. et.al (2009) /NeuroImage 47:1608-1619/;