Low and asymmetrical hippocampal glutamate levels in healthy older adults

Glutamate (Glu) is a critical molecule in cellular metabolism and the most abundant excitatory neurotransmitter in the brain. Glutamate dysfunction is common in neurodegenerative disorders—patients with Alzheimer’s disease (AD) have lower hippocampal glutamate—and likely contributes to age‐related declines in cognitive functioning. The extant literature on age‐related changes in brain Glu is small and all studies have employed proton spectroscopy. Thus, in this investigation we use a novel 7T magnetic resonanace imaging technique, Glutamate Chemical Exchange Saturation Transfer (GluCEST), to compare bilateral hippocampal brain Glu in between healthy old and young adults.