Even as younger adults, people’s ability to remember past events differs, and these differences grow as we age. Together with researchers in Dresden and Berlin, ARC psychologists Goran Papenberg and Lars Bäckman set out to better understand why.
They chose to look at variations in genes related to dopamine and glutamate, two neurotransmitters important for learning and memory. Neurotransmitters are signaling substances. In the brain, they transfer impulses between neurons (brain cells).
– We thought dopamine and glutamate were particularly interesting because animal studies show their combined effect on memory is stronger than their individual effect, says Goran Papenberg.
The team found the first evidence in humans that variations in genes related to the two neurotransmitters interact to impact our episodic memory—that is, our memory for past events. The effects, however, are only apparent when we are older: the researchers observed differences in memory among 59- to 71-year-olds but not among 20- to 31-year-olds. Importantly, older adults who carried two advantageous gene variants performed similarly to younger adults. The study’s results explain part of the increasing variation in memory as we age.
Read the abstract.
A scientific article describing the study was published in May: Papenberg G, Li SC, Nagel IE, Nietfeld W, Schjeide BM, Schröder J, et al. Dopamine and glutamate receptor genes interactively influence episodic memory in old age. Neurobiol Aging. 2014 May;35(5):1213.e3-8. doi: 10.1016/j.neurobiolaging.