Why depressed people cannot hold on to positive memories and emotions.
Depressed people have 30% worse memory on certain tasks, research finds.
Depressed mood stops people from holding information in their memory.
This may be why depressed people can find it hard to hold on to positive memories and emotions.
It can also help to explain how depression develops and persists over time.
In depressed people, memory is easily ‘hijacked’ by depressing thoughts, to the exclusion of all else.
Professor Bart Rypma, who led the study, said:
“People with depression or even healthy people with a depressed mood can be affected by depressive thoughts.
We have known that negative thoughts tend to last longer for those with depression.
However, this study is unique in showing that, these thoughts, triggered from stimuli in the environment, can persist to the point that they hinder a depressed person’s ability to keep their train of thought.”
In the study, 75 people read sentences that sometimes had depressive features.
The results showed that people who were depressed did 30% worse in a memory test when reminded of a depressing thought first.
Dr Nick Hubbard, the study’s first author, said:
“We all have a fixed amount of information we can hold in memory at one time.
The fact that depressive thoughts do not seem to go away once they enter memory certainly explains why depressed individuals have difficulty concentrating or remembering things in their daily lives.
This preoccupation of memory by depressive thoughts might also explain why more positive thoughts are often absent in depression; there simply is not enough space for them.”
Professor Rypma said:
“Interventions such as mindfulness-based cognitive therapy are quite successful in empowering depressed people to recognize and better regulate the content of their thoughts.
Our goal is to continue to study how such therapeutic approaches can alter the depressed brain and how these alterations might result in better memory and outcomes for persons with depression.”
The study was published in the Journal of Affective Disorders (Hubbard et al., 2016).