Abstract #4383

Using Short TE 1H MRS Methodology for the Reliable Detection of GABA in the Human Amygdala

Ralf Mekle¹, Simone Kuehn², Tomasz Dawid Lindel¹, Florian Schubert¹, Juergen Gallinat³, Bernd Ittermann¹

¹Medical Metrology, Physikalisch-Technische Bundesanstalt, Berlin, Germany; ²Department of Experimental Psychology and Ghent Institute for Functional and Metabolic Imaging, Ghent University, Ghent, Belgium; ³Clinic for Psychiatry and Psychotherapy, Charit University Medicine, Berlin, Germany

The tiny amygdala is believed to a play central role in conditioning, i.e. in the expression of fear and anxiety, which is controlled by inhibitory GABA (γ-aminobutric acid)-ergic circuits. Measurement of GABA levels within the amygdala would allow to explore the neurochemical basis for conditioning and associated pathologies. However, performing MRS in this region is challenging due to its small size and testing B₀ and B₁ conditions. In this study, short TE ¹H MR methodology using the SPECIAL technique was applied to overcome these limitations. GABA was reliably detected (CRLBs<20%) in N=8 volunteers, and slightly elevated concentrations were found.