Sussex Neuroscience

Professor Mara Cercignani

MaraNovel in-vivo multimodal imaging approaches to characterize CNS pathology

BSMS

Quantitative MRI techniques provide indices that reveal neural tissue properties non-invasively, thus offering an invaluable tool to investigate the pathological substrate of neurological diseases. My group focuses on the development, optimisation and application of multimodal approaches based on MRI and neurophysiology to assess the structure and function of the CNS. The techniques that we use include diffusion-weighted (DW) MRI, which probes tissue microstructure by measuring the motion of water molecules within tissue; magnetization transfer (MT) MRI, which enables the estimation of myelin, the insulating material wrapped around the neurons; metabolic MRI techniques, that measure perfusion and oxygen extraction fraction; and sodium MRI, which probes directly the concentration of sodium in the brain. We combine these MRI indices with non-invasive brain stimulation (TMS and tES). Thanks to the collaboration with the Quantum Systems and Devices group (https://www.sussexquantum.com), we are pioneering the use of atomic sensors for the direct measurement of neuronal currents.

Examples of projects currently available:
1. Combining neurophysiology and MRI to study hidden symptoms in MS (in collaboration with Dr Bozzali):
While a number of pharmacological treatments have proved effective in reducing or slowing down the accumulation of physical disability in relapsing-remitting MS, “hidden” symptoms such as fatigue, depression and cognitive impairment can impact of the quality of life of patients and their carers. Using a combine approach, we explore novel hypothesis about the mechanisms of these symptoms, with the aim of identifying new non-pharmacological approaches to treatment.

2. Measuring the cerebral metabolic rate of oxygen (CMRO2) non-invasively (in collaboration with Dr Colasanti)
While functional MRI and the BOLD signal have become a very popular method for localising neural activity, it is a very indirect means of measuring it. In particular, as it relies on neurovascular coupling, changes to both, vasculature and brain activity can affect it. More quantitative approaches to measure oxygen extraction are avaible, which combined with MRI measures of perfusion, can yield a quantification of CMRO2.

3. Measuring the effects of inflammation on the brain (in collaboration with Dr Colasanti and Cardiff University)
A role for inflammation in the major neurological and psychiatric conditions is increasingly recognised. Although no MRI technique is able to directly capture inflammation, we have a range of methods that can detect the effects of inflammation on the brain, such as increased BBB permeability, microglial morphometric changes, and metabolic effects. We develop and test novel MRI methods using experimental models of inflammation.

4. Pioneering the use of oxygen-enhanced (OE) MRI (in collaboration with Dr Colasanti and UCL)
When inhaling elevated level of oxygen, molecular oxygen remains mostly dissolved in blood plasma, caused a change in the MRI signal due to the magnetic properties of O2. This technique has been used to identify hypoxic tissue within tumours. Building on this success, we propose to extend the utility of OE MRI to measuring brain parenchymal oxygenation under normal conditions.
Working in my laboratory, the student will gain expertise with state-of-the-art imaging methods that can be applied to the study of many diseases as well as more broadly to neuroscience. The successful applicant will have some background in neuroscience or neurology. Some knowledge of image processing and medical imaging is an advantage, as is some technical background in programming.