PSEN1 and Alzheimer disease: Liang et al. (2017) in their 1H-MRS assessment of the hippocampal region in 12-month-old APP/PS1 transgenic AD model mice, observed a decrease in NAA/Cr and Glu/Cr an increase in mI/Cr. These results are consistent with previous reports. Furthermore, the hippocampus is one of the earliest affected regions in AD pathology (Hampel et al., 2011; Rao et al., 2022), the decline in NAA levels in the hippocampal region could potentially serve as a biomarker for early AD diagnosis.