Why it’s harder for aging brain to make new memories

Mouse study looks at why it’s harder for aging brain to make new memories.

New research suggests that just as cluttered and fragmented files in the hard drive slow an aging computer, a comparable process seems to take place in the human brain, making it harder to learn new information.

In the hippocampus, a brain structure critical to memory, the NMDA receptor acts like a switch for regulating learning and memory, working through subunits called NR2A and NR2B.

NR2B is expressed in higher percentages in children, enabling neurons to talk a fraction of a second longer; make stronger bonds, called synapses; and optimize learning and memory. This formation of strong bonds is called long-term potentiation.

Neuroscientists say the ratio shifts after puberty, so there is more NR2A and slightly reduced communication time between neurons.