What's Happening in the Brain
It is common for people with Alzheimer's disease to withdraw somewhat, and often this begins by withdrawing from situations that are unfamiliar. Families notice that the person they care for is more reluctant to go out, even on familiar and previously enjoyable ventures, such as a trip to the store, or to church. The person with dementia might complain of being 'too tired' to go, or when there, might complain that 'everything is too noisy'. Sometimes they will say 'I can hardly hear myself think.'
Even in the early stages , many dementias can cause changes in people which undermine their confidence to go out. They might be frightened of getting lost, especially if it has happened to them, and they remember it. They might have been embarrassed by something that happened, or disconcerted by their inability to remember which items to pick up, or to make change. In other words, they begin to withdraw for reasons that are understandable, and a conscious reaction to their illness. But dementia can also undermine their ability to initiate activities, and to understand the motivations of other people and react to them in a way that is socially appropriate. Each of these brain functions (initiative, sense of self, understanding the motivations of others) requires that the neural circuitry which goes through the brain's prefrontal cortex is intact.
In addition to these important functions (collectively sometimes referred to as 'social conduct'), interaction with other people requires intact language abilities , as well as enough memory to get by. Each of these functions (social conduct, language and memory) is affected in Alzheimer's disease, and to varying extents, in other dementias too. Even given the importance of the pre-frontal cortex, there is not a single 'part of the brain' which is affected to give rise to these problems. Effective social conduct requires the integration of many brain functions. On the other hand, the failure of social conduct is not just a non-specific brain problem, because many families report characteristic changes in social interaction over the course of the illness, as follows:
|Description of activity
|Initial effects, very mild dementia
||People begin to lose interest in common social activities. They will initiate them less often, but remain content to go, and are interested in the events while they are there. They will commonly talk about the activity afterwards.
|Early effects, mild dementia
||People rarely initiate social activities, but are still content to go. They mostly enjoy the activities when they are there, with some carry over so that they feel better afterwards. They often do not speak of the activities later, although might admit to some embarrassment at a particular event, but are just as apt to remember something pleasant.
|Common in established, mild dementia
||People no longer initiate social activities, but are usually content to go. They enjoy the activities as long as they last, but often this enjoyment does not carry over to the rest of the day. They rarely talk about the activities afterward. They might, however, remember or even dwell on hurtful aspects of the experience (such as forgetting a friend's name).
|Seen later in mild dementia
||People begin to resist going to social events, even if they seem to have a good time while there. Often they remember little about the event, even within the same day.
|Suggests moderate dementia
||People routinely resist social events, and, when there, often ask to leave, even after only a few minutes. They can often act in a stubborn enough way that family members worry about taking them out. People with dementia at this stage seem to have no memory of an event afterwards, although a low mood due to some incident can stay with them.
|Common in moderate dementia
||People actively resist going out, and can even be belligerent. Often, families will limit outings to very familiar environments. Sometimes, however, patients will still manage to interact appropriately, in superficial ways, such as smiling at children, or nodding to passersby. As above, they often seem to have no memory of an event afterwards, although a low mood due to some incident can stay with them.
|Seen with severe dementia
||People can be taken out because they are very passive, and rarely interact with strangers at all, either positively or negatively.
What we can conclude from this is that there are some specific patterns in the failure of the brain circuits which control social function. This gives hope that specific treatments might target those circuits effectively. Many families report improvement in many aspects of social conduct after treatment with cholinesterase inhibitors . Sometimes, too, treatment with certain types of anti-depressant medications can improve social conduct in people with dementia. This suggests that the brain circuits that require the brain chemicals augmented by those medications (such as serotonin, brain levels of which are increased by many anti-depressants) are affected in dementia, and give rise to the characteristic changes in behaviour described above.
As far as we can tell, there are real brain benefits for people with Alzheimer's disease to continue to interact socially. In fact, people who have higher levels of social interaction seem to be at a lower risk of developing the disease.
Further reading for what is happening in the brain:
Fratiglioni L, Paillard-Borg S, Winblad B. An active and socially integrated lifestyle in late life might protect against dementia. Lancet Neurol. 2004;3:343-53.