Loneliness is considered a negative feeling associated with dissatisfaction with the quantity and quality of social connections. Being lonely does not necessarily imply being alone. Thus, one can be surrounded by people and still feel lonely. Loneliness affects physical and mental health and also increases the risk of cognitive decline.
Loneliness was measured using questionnaire items including if one feels to be part of a group or whether one has people whom they can talk to.
Episodic memory was measured using word-recall tasks.
Loneliness linked to memory decline in some people
Using European longitudinal data of participants over time, the researchers found that feelings of loneliness were associated with memory decline among the Swedish participants but not the German ones.
“Cultural differences in how people perceive and deal with social isolation could partially account for the differences encountered,” says lead author of the study, Cristina Solé-Padullés, from the University of Barcelona.
Link driven by dementia
Further, the association between loneliness and memory decline among the Swedish cohort was lost once some participants were excluded after having developed dementia during study assessments. The fact that this association was no longer significant once these patients were ruled out reinforces the association between loneliness and cognitive decline, already found in previous studies.
Loneliness not linked to brain structure
Previous studies have pointed out that some brain regions linked to emotional processing and empathy could be the key to the neurobiology of loneliness. This Lifebrain study therefore also wanted to explore whether loneliness could be linked to particular brain structures. They coupled MRI data to participants’ feeling of loneliness. However, no significant associations were found between loneliness and any brain regions.
So, the answer to the question Does loneliness affect your memory? is therefore not clear-cut. Solé-Padullés concludes:
“Associations between loneliness and memory decline are not consistent among countries and ages, partly because there are cultural differences making some people more tolerant to social isolation. Loneliness can cause memory decline in some older adults, but memory decline can also cause increased feelings of loneliness”.
