Research Article

Posterior Cingulate Lactate as a Metabolic Biomarker in Amnestic Mild Cognitive Impairment

Figure 3

PPC lac correlations and brain pathology in aMCI. (a) PPC lac negatively correlates with ICV adjusted L (left) and R (right) hippocampal volumes. (b) Regions of posterior cingulate resting state fMRI functional connectivity that negatively correlate with PPC lac concentrations across aMCI. The PPC seed point (upper left inset) was selected with reference to the site of maximum FDG-PET impairment in a group of preclinical probable AD patients [26] and was contained within MRS voxel locations in all subjects (red transparent box). -statistics were calculated utilizing a Gaussian random field theory, thresholded using clusters determined by and a (corrected) cluster significance threshold of . Blue voxels showing significant negative correlations between the strength of functional connectivity and PPC lac concentrations, displayed on the MNI152 template brain and in radiological convention, were generally located within the temporal lobe including medial temporal loci (e.g., left hippocampus in upper left green crosshairs) and various subcortical structures (see Table 2). Coordinates (, , and ) are in millimeters in MNI space. MTG: middle temporal gyrus. pHG: parahippocampal gyrus. STS: superior temporal sulcus. HG: hippocampal gyrus. STG: superior temporal gyrus. POG: posterior orbital gyrus. Put: putamen.