PROJECT SUMMARY Edited magnetic resonance spectroscopy allows the non-invasive detection of low-concentration metabolites within the brain, such as the inhibitory neurotransmitter GABA and the redox compound glutathione (GSH). The signals of such metabolites are often overlapped in the MR spectrum, but a tailored spectral editing experiment can selectively retrieve signals of interest. Such “edited” approaches generally focus on measuring a single metabolite (i.e. either GABA or GSH) in a single brain region; the main goal of this proposal is to develop Hadamard-edited experiments that detect GABA and GSH simultaneously, in a single acquisition. We will develop the Hadamard-encoded HERMES approach, and multi-voxel Hadamard editing, using the SHERPA and HERMES-SHERPA approaches. The resulting data acquisition, post- processing and analysis tools will be made available for dissemination to the clinical neuroscience and neuroimaging communities.