Associate Professor Michael Valenzuela
When researchers talk about social engagement, they’re really talking about getting out of the house, and trying to measure that, getting out of the house to meet either your friends, family or new people. There are different ways technically to measure that. Sometimes it’s literally, “How often are you meeting or getting together with a friend or a family member?” You can get a little bit more complicated and actually try and map out people’s social networks, but the general idea is meeting people that you either know or new people, and outside of the house.
There’s now quite a lot, dozens, of population-based studies or public health studies, which really means you’ve got a large group of people who’ve been followed for a number of years, and that kind of research shows, time and again, that those who are more socially active have a lower risk of dementia. Or the inverse, if you’re socially isolated, then you have a higher risk for dementia. So, from that population-based research, I think there’s quite a lot of evidence for that. It becomes a little bit more difficult when we try and translate that to the clinical trials or interventions context, but I think the main message there is that social activity, social engagement, is a risk or a protective factor for dementia. I think that evidence is pretty strong. Moving from there, it gets quite complicated.
Why social engagement should be related to dementia risk is a really tricky question to answer. We’ve got lots of theories. If you just think about it in first principles, socialising with other people demands a lot of your brain. You need to work memory; a nice social interaction means, if you’ve met the person before, you remember something about them that you can incorporate in your conversation. You’ve got to plan ahead. You have to follow the niceties of social conventions, sometimes called EQ or emotional intelligence. It requires quite a lot of mental work. So the connection could be through cognitive exercise or cognitive demands. The other side of the equation is social activity, for most people, there’s an inherent reward feedback system there. It’s a pleasurable act, to go out and socialise, so that leads to more sustainable behaviour. So, once you start socialising, you get in the habit, you enjoy it and you do it more and more in your life. So there could be an emotional or emotive side to that link. Whether there is an inherent value to social activity and dementia risk, independent of either cognitive activity or the reward feedback, we don’t really know.
I guess on the negative side of social activity, if you’re withdrawn, you’re stuck in your house most of the time, not meeting your friends or family or not meeting new people, this is related to increased risk of dementia. And there are various sides to that observation. On the one hand, we do know that, in the years leading up to a dementia diagnosis, people start to withdraw somewhat from their social contacts, so it could actually be an early warning sign that maybe dementia is in the future for an individual. Or that person may be suffering from mental health problems, like depression, which means that you withdraw from your normal day-to-day activities and this leads to social withdrawal as well. So they could be two explanations for that observation, but I think there’s enough evidence from the public health literature, which tries to statistically adjust for those possible scenarios, and there is still a link between greater social activity being linked to reduced dementia risk. So I think there is some truth on both ends of the spectrum, that low social engagement is a risk factor for dementia, and high social engagement is a protective factor.
Unfortunately, I don’t think we can quantify what is the perfect amount of social activity. Putting a lot of different streams of research together in my book, which is called “Maintain Your Brain,” I really recommend a common sense approach to it, which is that, particularly after retirement, because a lot of things change in retirement - one of the more stark things is that people go from a social network at work to often having a much more restricted social network, so I think it’s really important after retirement that people try and replace that social engagement. And what that means, I think, in terms of recommendations, is that people should try and start some new pastime or hobby, or join some kind of interest group out there, which means they’ve got to leave the home, they’re meeting new people. Ideally it’s ticking off what I call the three keys: that it entails or has cognitive activity, social activity and some physical activity. If you can try and start a new pastime that has those three key ingredients, I think you’re doing a good thing to lower your risk for dementia.
不幸的是，我不认为我们可以量化什么是完美的社会活动量。在我这本名为“保持你的大脑”的书里，我把大量不同的研究结果放在一起，从而推荐一种特别是在退休后使用的一种常识性的方法。因为在退休后许多事情发生改变 – 其中更严峻的事情是人们在工作中的社交网络经常有一个更受限制的社交网络，所以我认为在退休后，人们试着换一种社交参与方式是非常重要的。我认为应该建议人们开始尝试一些新的消遣或爱好，或加入在那里的某种兴趣小组，这意味着他们必须离开家，去认识新朋友。理想情况下，它敲出了我所说的三个键：它需要或具有认知活动，社交活动和一些体育活动。如果你可以尝试和开始一个有这三个关键因素的新的消遣活动，我认为你在做一件降低你患认知症的风险的好事情。