A new study from University of Eastern Finland in Kuopio has found that cynical distrust– thinking that people’s actions are motivated by selfish means, could cause dementia later in life. “We are not born cynical, but our personality is something that develops during our lifetime,” explains Anna-Maija Tolppanen, the study’s lead author. This study is the latest in a long list of scientific evidence that shows how beneficial to have an optimistic outlook on life.
The Intelligent Optimist: Is personality an intrinsic characteristic, or can cynics change their personality to be healthier and prevent dementia?
Anna-Maija Tolppanen: It is tempting to hypothesize that attitudes/personality traits such as cynicism are modifiable and changing one’s personality may result in better health. However, this is the first study showing the connection between cynicism and brain health so we do need to confirm the connection in other studies. If this is confirmed, we need to find out how our personality affects the brain (i.e. whether it is cynicism itself that is hurtful) and whether changes in attitude, in addition to healthy lifestyle with physical and social activity and balanced diet, can result in better health.  
TIO: If cynics tend to be heavier and smoke more, is it possible that cynicism is a by-product of an unhealthy lifestyle, and not a core characteristic people are born with?
AT: Yes, this is precisely what we thought. These cardiovascular risk factors have explained the connection to cardiovascular diseases in some previous studies. However, they (or other cardiovascular risk factors, general health status, depression symptoms or socioeconomic background) did not explain the connection with dementia in our study. I also think that we are not born cynical, but our personality is something that develops during our lifetime.
TOI: How does cynical distrust physically impact the brain?
AT: There are many ways on how personality may affect brain health. People with different personality traits may be more/less likely to engage in activities that are beneficial for cognition (healthy diet, cognitive or social activities, exercise). Another suggestion is that personality may act via morphological changes or structural differences in brains. Also, inflammation has been suggested as one link between cynicism and worse health outcomes. 
Previous studies have linked cynical distrust to e.g. lower socioeconomic position and worse health status in general, which are also related to dementia risk. We investigated whether socioeconomic position, age, sex, health status, or different lifestyle factors (such as smoking, alcohol use) would explain the findings. They did not, but there are other lifestyle factors such as engagement in social activities (which is beneficial for cognition) that were not controlled for, which may explain the association. My guess is that the connection is not explained by one factor only, but it is more complex. 
TIO: How does pre–dementia affect our brain and personality?
AT: This is an excellent question. Some of the first signs of dementia may be changes in personality (e.g. irritability, anxiety, becoming more passive) and one possibility for our findings is that higher levels of cynicism are actually an indication of ongoing disease process.  
TIO: What further research would you like to do regarding cynicism and dementia?
AT: I am not currently working with the topic, but it would be very nice if other researchers could confirm our findings in other, hopefully larger studies. If the connection is confirmed, it would be important to assess why cynicism is related to dementia and if the changes in attitude can indeed result in better brain health.
TIO: What study are you working on or planning to work on next?
AT: I am currently assessing how persons with Alzheimer’s disease utilize healthcare services and conducting research on the effectiveness of different medical interventions. But I would be very interested to work with personality risk factors of dementia in future as well.