A question I have been asked in several job interviews, you might have been asked too, is
"Where do you see yourself in five years?" I never understood the purpose of that question, finding it quite annoying. If I knew how to predict the future I would probably earn a living betting at horse races. After learning about Dr Tali Sharot's work, I finally understand what the interviewer was trying to find out:
"Is the glass half full or half empty? Are you an optimist or a pessimist? "
Under the same circumstances an optimist and a pessimist extract
different conclusions and decide to take different actions. This means that the subjective interpretation of reality affects the objective
outcomes in the future. Optimists are less vulnerable to stress, anxiety and more keen to take actions than pessimists. Would you prefer to have an optimist or a pessimist in your team?
Neuroscientists have recently started to ask questions about what makes an optimist view the glass as half full: Are the brains of optimists different than the brains of pessimists? Is there a genetic predisposition for being optimistic or pessimistic? Can we learn to be more optimistic?
Today, the curious neuron is talking to Dr. Tali Sharot and her team members, Neil Garrett and Caroline Charpentier to ask them about optimism. Tali Sharot has been looking for the brain activity that underlies the optimism bias, using the combination of both behavioral tasks and fMRI to unravel how an optimistic brain functions.
Tali Sharot explains that when estimating the future, the brain pictures an illusion of bright and magnificent events waiting ahead. This is called
the optimism bias. The majority of people (a surprising 80%) overestimate the chances of positive things that might happen to them in the future and underestimate the negative ones. This optimistic expectations are primarily focused on themselves rather than on others.
When people are diagnosed with a serious disease, or are victims of violence, they tend to say: "Never thought that something like this would happen to me, because something like this only happens to somebody else..."
Tali's work is extensive, and cannot be covered properly in a blog post. If you want to find out more check the webpage
The Affective Brain Lab in UCL. Here goes a brief summary of her findings for the curious neuron's readers:
Tali, do you think optimism links to happiness?
“Optimism is not about happiness, it is related because anticipation of a good thing makes us feel good at a moment. Optimism is about expectations is very easy to measure and allows mathematical modelling. Happiness is very difficult to measure and hence to analyse.
Sometimes the anticipation of a reward is even better than the reward itself”.
Human action is influenced by the expectancies of reward.
How does the brain increase these expectancies?
According to Tali and her colleagues, through dopamine.
Dopamine (DA) is a neurotransmitter that has a modulatory role in the subjective expectation of pleasure. It has been linked to drug craving and consumption. Tali and her colleagues in University College London wanted to find out if DA would also have an impact on subjective estimations of future pleasurable events. They asked subjects to choose from a list of vacation destinations where they would be happier to take their next vacation. They administrated L-Dopa (a drug that enhances DA function in the brain) in a group of subjects and found that there was an enhancement on the preference of their choice.
"Although DA did not increase the feeling of happiness it did enhance a prediction of pleasure for an imagined event".
Understanding the biological traits that underlie optimism
In a study carried out at New York University, Tali and her colleagues tested how the brain processed positive and negative information, finding that there was a difference in the correlation of the activity of the rostral anterior cingulate cortex (a cortex usually active in error detection) and the amygdala (involved in emotional processing). For positive information, the correlation was high, yet for negative information the correlation between the activity of these structures decreased.
This led researchers to suggest that depression could be caused by a decrease in the regulatory effect between rACC over the amygdala.
Tali, was it a surprise to find certain brain structures linked to optimism bias?
“What is relevant is not which areas of the brain are involved in optimism bias, but rather that the activity of these structures is biased.
For example, it is quite known that the inferior frontal gyrus is related to error learning, but what's interesting is how it's activity is biased when processing negative information”.
How can the brain remain optimistic when exposed to reality?
In research also conducted in University College London (UCL), Tali and her colleagues studied if the brain would remain optimistic after being confronted with real information. In other words, how does the brain deal with negative information?
Subjects were asked to estimate the likelihood of suffering negative events in the future. The list of these negative events included having cancer, Alzheimer's, or being robbed. The majority of subjects underestimated the probability these events might occur to them, with no effect of familiarity, arousal or past experiences. Subjects were shown the real probabilities of these events. Subjects were then asked to repeat their estimations of each event. Researchers found that subjects were more accurate when the update was optimistic rather than pessimistic. The learning curve for positive information was steeper. Could the brain be processing negative and positive information differently?
When looking at the brain activity of the participants in the fMRI scanner, researchers found that the activity of the bilateral medial prefrontal cortex(mPF), superior frontal gyrus (SFG) and right cerebellum predicted the update of desirable information while the activity in the right inferior frontal gyrus (IFG) predicted the update in response to undesirable information.
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| Image of a sagittal section of the brain taken from a fMRI scan. |
Does the optimistic brain activity differ from the rest?
Although the majority of subjects had made optimistic predictions when estimating future negative events, certain subjects had been extra optimistic. The brain of the extra optimistic participants showed no activation of the IFG when confronted to undesirable information.
All subjects showed a similar pattern of brain activation for positive information, yet the right inferior frontal gyrus (IFG) of optimists' brain hardly activated when exposed to negative information. Leaving optimists hardly aware of negative information.
How can people maintain their optimism bias even if there is no reward to it? For example, the chances of winning the lottery are very low. Yet there are people that buy a lottery ticket every day thinking that they might win the jackpot. Why is it that this behaviour is not extinguished?
“People don't win the lottery but they see others that do, it's social learning. “I didn't win but I might win next time”. They overestimate the chances of winning the lottery. And yet when they see others suffering from cancer they think that the chances of that happening to them are lower than what they really are.
Optimism bias deals with possibilities, with estimates not with outcomes. It's unconstrained, once you have an outcome then it is different. Information that is unconstrained affects more when it's desirable than when it is undesirable. You learn faster when the information fits your optimism bias”.
The people that don't develop
postraumatic disorder, would this people have more optimism bias?
Yes, they probably would. Optimism
bias is a strategy to cope, it's like a psychological immune system.
Could you learn to be more
optimistic?
Studies by Martin Seligman have
demonstrated that even individuals who are vulnerable to depression
can learn to be optimistic.
Optimists tend to be surrounded by
people and have more social support, could it be because optimism is
contagious?
It seems that optimism can be
contagious. This is something that Fowler and Christakis are demonstrating through their work on social networks. They also proved that the chances of being obese are higher if your friends are obese, being happy also is affected by the people that are happy around you.
Tali is one of the few researchers I've met who has been brave enough to write a book for the general public. Tali's book got excellent reviews was selected as top ten reading from The Guardian. To find out more about the book:
the optimism bias book.
You've written the book a about
optimism bias, could you tell us a bit about it?
“It was really nice to write, less
constraining than writing a scientific paper, it gave me the chance to
talk about other people's work and relate it to optimism bias.
Although the book is targeted to the general public, scientists can
also read it because it is accurate enough”.
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Tali Sharot's book explaining the Optimism Bias
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Why does the optimism bias have an adaptive function? Isn't it better to have a realistic estimation of your
chances?
“
If you are mildly optimistic then
it is adaptive, it pushes your chances further because it motivates
you to act. Optimists are healthier and less vulnerable to stress and
anxiety. Optimism stops being adaptive in extreme cases, when you
underestimate your risks”.
How sophisticated is the optimism bias?
Animals have an optimism bias as well (Matheson et al., 2008; Mendel et al., 2009). It must be very basic, if we had a way of testing it, we would find it in many living organisms.
Optimism bias has been shown in rats, dogs, rhesus monkeys and starlings. In an experiment involving starlings, Matheson et al, 2008 found that birds were more likely to interpret an ambiguous sound as related to a positive outcome when kept in enriched environments. Sterlings that lived in non-enriched captivity conditions showed no optimism bias.
How important is having a sense of control over the future?
“I think that having a sense of
control generates optimism.
People who suffer depression have
pessimistic thoughts, have no sense of control over what happens to them,
no future planning, are less active and their health is affected”.
Since you are working on optimism bias, have you noticed any change in the way you view life?
“My theory is that becoming aware
of optimism bias doesn't make the bias disappear but it can led to do
the actions that you need to protect yourself. For example, I have
noticed that for a while I have been doing proper stuff, like wearing
a helmet when riding a bike, going to all medical scan appointments,
buying insurance for my computer...”
It is always interesting to find out what are the insides of an experiment like, so I dragged Neil and Caroline, members of Tali's team, to the cafeteria and asked them about their experience working in optimism bias.
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| Caroline Charpentier and Neil Garrett, members of Sharot's research group. |
What involves an experiment using behavior and fMRI?
Usually there are several stages before participants are taken to the fMRI. There is a lot of previous pilot work, you want to make sure that you have a behavioral effect before doing the fMRI, which could not necessarily produce a clear neural activation to show in the fMRI.
Designing a task to be carried out in the fMRI scanner can be tricky, participants are under a big magnet and can't move from shoulders up, this is why tasks usually involve pressing buttons in a computer, with visual stimuli appearing in a screen. Auditory tasks can be a problem because the fMRI scan produces a lot of noise.
After the fMRI months of analysis follow.
Where do you usually get volunteers for your studies?
"We usually recruit students as being on a university campus these are easy to come by. A criticism of fMRI studies is general is that they aim to find "an average person" which is difficult. Yet, so far the robust findings have been replicated".
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Preparing a subject for an fMRI scan
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Subject in the fMRI scanner
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What do you think the optimism bias could be useful for?
As Tali says, it motivates you to keep striving in life but on the down side people take unnecessary risks like smoking and underestimating your chances of getting cancer.
Optimism bias is present in all ages? Is optimism bias related to hormone levels?
"We are not sure yet. However studies on people's happiness suggest that people are happiest when young and old and less happy during mid life".
Do you think there could be any hormone relation to optimism bias that could explain age differences?
Neil says "I don't know about hormone levels really but there is research relating genetics, optimism and happiness, like the work by De Neve".
Since you've are working on optimism bias have you noticed you have changed your habits at all?
Caroline explains "I tried not to think about the effect, I had the feeling I was more pessimistic than normal by overestimating risks, so maybe I am not as optimistic as I should".
Neil adds "It's like an optical illusion, you can not stop yourself, even if you know about it, it's how your brain is wired".
Do you need an optimism bias to start a PhD?
Neil and Caroline laugh"Maybe".
Neil points out that "Most projects underestimate the budget and the time it will cost to finish them".
Could you think of any example of everyday life where you can find optimism bias?
Neil comes up with a couple of interesting examples:
"The financial crisis in 2008 is an example, as although everybody knew that stock market can go up or down, nobody thought that this would happen to them, and there was an optimism bias thinking that the stock market would always go up.
"Setting yourself targets for work, you think you are going to accomplish all your tasks but you never do, and the next day you set high expectations over your productivity again. Although this probably is helping you to achieve more than you would if the your targets were not as ambitious".
Caroline brings up an example of divorce rates
"Couples that are getting married underestimate their chances of divorcing".
I would like to thank Tali, Caroline and Neil for their time and kindness, without them this post wouldn't had been published.
References
De Neve JM
"Functional polymorphism (5-HTTLPR) in the
serotonin transporter gene is associated with
subjective well-being: evidence from a US
nationally representative sample"
J of Hum Gen (2011) 56, 456–459
Fowler JH, Christakis NA "Dynamic spread of happiness in a large social network: longitudinal analysis over 20 years in the Framingham Heart Study" BMJ 2008 Dec 4, 337:a2338.
Matheson SM, Asher L, Bateson M "Larger enriched cages are associated with optimistic response biases in captive european starlings (Sturnus vulgaris)"Appl Anim Behav Sci (2008)109:374-83.
Mendl M, Burman OHP, Parker RMA, Paul ES. "Cognitve bias as an indicator of animal emotion and welfare: emerging evidence and underlying mechanisms" Appl Anim Behav Sci (2009) 118:161-181.
Sharot T, Riccardi AM, Raio CM, Phelps EA. "Neural mechanisms mediating optimism bias" Nature 2007 Nov 1;450(7166):102-5.
Sharot T, Shiner T, Brown AC, Fan J, Dolan RJ."Dopamine enhances expectation of pleasure in humans" Curr Biol. 2009 Dec 29;19(24):2077-80.
Sharot T, Korn CW, Dolan RJ "How unrealistic optimism is maintained in the face of reality"
Nat Neurosci 2011 Oct 9; 14(11): 1475-9.
Sharot T. "The optimism bias"
Curr Biol. 2011 Dec 6;21(23):941-5
Books
Sharot T. "The optimism bias: why we're wired to look on the bright side" Ed. Constable & Robinson Ltd. 2012
