Date Published: 21 September 2017
Research confirms that good and bad moods are contagious. Depression isn't.
Are states of mind, or 'moods', socially contagious?
Expressed another way, might happy friends cheer us up and / or worried or dissatisfied friends reduce our own feelings about our life and situation? What about depression - is that contagious?
Recent research by academics at the Universities of Warwick and Manchester, in England, indicates that while both 'good' and 'bad' (positive and negative) moods can be 'picked up' from friends, depression can't. The latter is good news in view of the World Health Organisation's estimation that more than 300 million people of all ages suffer from depression globally, a 'leading cause of disability worldwide' and 'a major contributor to the overall global burden of disease', in some cases leading to suicide1.
The recent study2 used statistical methods to consider the extent to which friends' moods affect people, something which if found to occur to a significant extent, would suggest that states of mind can spread through friendship networks.
The team analysed data from the National Longitudinal Study of Adolescent to Adult Health3, which incorporates the moods and friendship networks of teenagers in American schools, and found that mood or 'state of mind' does spread over friendship networks, as do various different symptoms of depression such as helplessness and loss of interest. However they also found that the effect from lower or worse mood friends was not strong enough to result in others, such as their immediate friends, becoming depressed.
Public health statistics researcher Rob Eyre led the study and summarized 4:
" We investigated whether there is evidence for the individual components of mood (such as appetite, tiredness and sleep) spreading through US adolescent friendship networks while adjusting for confounding by modelling the transition probabilities of changing mood state over time.
_ Evidence suggests mood may spread from person to person via a process known as social contagion.
_ Previous studies have found social support and befriending to be beneficial to mood disorders in adolescents while recent experiments suggest that an individual's emotional state can be affected by exposure to the emotional expressions of social contacts.
_ Clearly, a greater understanding of how changes in the mood of adolescents are affected by the mood of their friends would be beneficial in informing interventions tackling adolescent depression."
Mathematical models helped to reveal that based on the data used in the study, having more friends who suffer worse moods is associated with a higher probability of an individual experiencing low moods and a decreased probability of improving. The opposite applied to teenagers in a more positive social circle.
The study also helped to highlight the distinction between depression and merely a 'low' mood. In addition it is useful to note the implication from this work that following general advice for improving ones mood and taking care of ones mental health, e.g. in terms of appropriate healthy exercise, sleeping well, and managing stress, can help teenagers' friends as well as themselves. On the subject of depression, as other people such as friends are not put at increased risk of illness, a positive course of action would be to show support to those affected.
Prof Frances Griffiths of Warwick Medical School, also co-author of the study, went on to explain that 4:
" The results found here can inform public health policy and the design of interventions against depression in adolescents. Sub-threshold levels of depressive symptoms in adolescents is an issue of great current concern as they have been found to be very common, to cause a reduced quality of life and to lead to greater risk of depression later on in life than having no symptoms at all.
_ Understanding that these components of mood can spread socially suggests that while the primary target of social interventions should be to increase friendships because of its benefits in reducing of the risk of depression, a secondary aim could be to reduce spreading of negative mood."