Social activity and the brain

Introduction

In the past, research has looked at the impact of social stimulation on the brain development of laboratory animals like rats and mice. More recently, researchers have started to look at human social interaction and how it might influence a person’s health in general and, particularly, his or her risk of developing dementia. There are, as yet, few human studies. This chapter looks at the evidence so far and suggests how you can maintain and develop new social activities which may be good for your brain.

Why does social activity help the brain?

As with physical and mental activity, there may well be a ‘use it or lose it’ phenomenon at work. Being involved with other people requires us to communicate effectively and take part in complex social exchanges, requiring the use of various parts of our brains. It also gives us a place or standing in the family and the community and a sense of purpose in life, which can contribute to feelings of well-being. Having greater self-esteem and a sense of purpose in life may in turn lead to better self-care through keeping active and eating a balanced diet(75).

Having good social networks may also give us the emotional support needed to help us cope better with stressful situations, and any depression, grief and loneliness that may affect us as we go through life. Work may help to provide us with a stimulating environment – it therefore becomes important to plan for retirement, not just financially, but also to plan what you are going to do with your time to keep busy and involved.

What’s the evidence about social activity and dementia?

Research has suggested a possible link between levels of social activity and the way people’s brains perform. Those with an active social network and those who take part in social activities seem to have a lower risk of dementia or, at least, a reduction in cognitive decline.

It is not clear whether being more socially active lowers the risk of dementia or whether people who go on to develop dementia are less socially active because they are already in the early stages of dementia, even before any symptoms show. More research is needed before any cause and effect could be shown.

The previous chapter on mental activity looked at the issue of cognitive reserve. It is possible that socially stimulating activities as well as mental stimulation also help individuals build a level of cognitive reserve. Researchers in Chicago explored whether a person’s level of involvement in social networks of family and friends, could be related to changes in cognitive function (76). 6,102 people took part in up to three interviews over roughly five years. The researchers found that people with more social networks had higher levels of cognitive function to begin with; they also found that those people had lower rates of cognitive decline over the years of the study.

One American study suggested that people who have no social ties (to spouses/partners, children, other relatives, friends, church or other community groups) are at around twice the risk of later cognitive decline compared with people with five or more social ties(77).

A lot of the evidence of the benefit of social activity comes from Swedish studies which have produced several insights into the role of social and psychosocial factors in dementia, including education, life events, personality, occupation and economic status, leisure activities, social networks and depression.

One of the Swedish studies found that having an extensive social network seems to protect against dementia. Having a poor or limited social network increased the risk of dementia by 60%(78). Later studies from the same large-scale project found that activities involving mental, physical and social stimulation individually offered some protection against dementia (79), but activities that combined two or three of these offered the most benefit(80).

The Swedish research also suggests that it is not necessarily the quantity of social interaction that counts but the quality. Those who had unsatisfactory contact with their children seemed to be at more risk than those who had no children. They were also at more risk than those who had good relationships with their children, even if they saw them less often. The data also suggests that being single seems to raise one’s risk – there seemed to be no difference in risk between widowed or divorced people living alone and widowed or divorced people who live with others. Another finding from this project is that it is not enough to have just one strong social bond, for example to a spouse/partner or to children; risk of dementia is lowest among those who a number of strong relationships.

The same Swedish project also investigated the role of inactivity (physical or mental), depressive symptoms and social isolation. Inactivity and depression were each associated with an increased risk of dementia; when combined with a poor or limited social network, there was about a 5.5% increased risk of developing dementia(81).

It appears, therefore, that it is not just one risk factor or behaviour that can make a difference to a person’s risk, but a combination of factors.

A large scale British study(82) of more than 10,000 civil servants aged between 35 and 55 found that taking part in various leisure activities was associated with a higher level of cognitive ability. The 13 activities studied were split into those involving low mental effort (like visiting friends, gardening and home maintenance) and those involving high mental effort (such as indoor games like cards and chess, reading or listening to music, and involvement in clubs and organisations). They were also divided into categories depending on whether they were solitary activities or those done with other people.

The research found that taking part in leisure activities was good for brain function but those activities that involved more mental effort were better than those needing less mental effort. The activities that involved other people were also linked to better cognitive function. This supports the findings of the Swedish study above which suggested that a combination of mental and social activities may be good for your brain.

Depression
While it is common for people with dementia to show signs of depression after they have been diagnosed, some research has suggested that depression may be a risk factor for dementia. One review found that having a history of depression doubled the risk of developing dementia(83). Another retrospective study (84) found that there was an association between depression and dementia even where the first signs of depression came 25 years before a diagnosis of dementia.

Other research at the Mayo Clinic in the United States suggests that even having a negative or pessimistic outlook on life can increase the risk of developing dementia by up to 30%(85).

While we cannot say that being socially active will prevent people becoming depressed or give them a more optimistic view of life, it may help them cope with the symptoms of depression or see the good things in life rather than the bad.

How to keep socially active

Keep involved in the world around you. Try to make sure you do something sociable and enjoyable every day.

Activities which combine mental, physical and social stimulation may be even better for reducing the risk of dementia; for example, day or evening classes, walking with a group or taking part in community groups.

• Keep in regular touch with friends and family – it doesn’t have to be face-to-face. Try phoning, writing or emailing
• Go out with friends, family or colleagues
• Get involved in your community
• Volunteer for something that interests you
• Join a club
• Join a walking group or a dance class – it will also increase your physical activity
• If you are coming up to retirement, think about how you will stay socially involved. Being retired gives you the chance to get involved in all sorts of groups and activities you may not have had time for when you were working.

Your local public library and local council should be able to give you details of groups and classes you might want to join.

The local volunteer centre will have details of local charities and voluntary organisations needing volunteers. Visit www.volunteerscotland.org.uk for more information on volunteering.

Next section: Other risk factors
References
Glossary
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Useful links:

Information about dementia
Volunteer Scotland
Volunteer to help Alzheimer Scotland