Depression affects memory by 'impairing ability to differentiate similarities'

Depression has long been known to affect memory, but it has been unclear how. Now, researchers say that one reason for this is that depression impairs the process of "pattern separation" - the ability to differentiate things that are similar.

Researchers from Brigham Young University define pattern separation as a mechanism for encoding memories, where distinct memory representations are created for similar objects and events.

But the team's findings, published in the journal Behavioural Brain Research, suggest that depression interferes with this process, and that the more depressed a person feels, the more difficult it is for them to distinguish between similar experiences they have had.

For the study, the researchers conducted a computer-aided memory test on a group of participants who showed symptoms of depression, but who were not receiving medication.