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If you take a rat, bring it to a blue painted room in a research lab and place it in a cage, it will be calm.


However, if once placed in the cage, you administer an electric shock (a procedure that has been previously accepted by the research ethics board), the rat will be extremely stressed and frightened.


If, after giving it a few days to rest, you place it in a cage in a yellow painted room, the rat will behave normally.  It will be calm.  However, if after giving it a few days to rest, you put it in a cage and place it in the blue room, it will be extremely stressed and frightened, even if you do not expose it to a shock.


This reaction occurs because the first time that the blue room is associated with the occurrence of an electric shock, ‘fear conditioning’ is introduced to the rodent’s brain.


What scientists call ‘fear conditioning’ is a form of learning in which an association is created between an unpleasant and/or negative event (in this case the electric shock) and a usually safe stimulus (a blue room in the laboratory). When this association is created in the brain, it leads to a fear of the previously safe stimulus.  What is fascinating about fear conditioning is that it usually occurs in a single try.  Many trauma victims will be able to tell you that it only took one event for them to become constantly afraid of the situation that traumatized them.  Although fear conditioning explains the feelings experienced by people who have been exposed to a traumatic event, it also applies to other forms of fear.


Fear conditioning is somewhat similar to what we are experiencing with the COVID-19 pandemic.  Previously, we used to be able to hang out (less than two metres apart) with dozens of people every day without being afraid of these social interactions.  This context (social interactions less than two metres apart) was not associated with any danger and therefore, no sense of fear.  Then the COVID-19 pandemic broke out, and governments declared a health emergency, telling us that if we stood closer than two metres to others, we increased the likelihood of catching this potentially deadly virus.


For many of us, a single exposure to this information was enough to generate a significant fear of social interactions occurring at a distance of less than two metres.  Over the past few weeks, we have read many articles and publications from a variety of sources about people yelling at others urging them to move away because they were standing too close and this scared them. Thus, something that was previously not associated with any sense of fear (social interactions of less than two metres) has become an indicator of danger for many people, and thus has become very frightening to them.


This fear, which takes place in a single exposure, is necessary to ensure the survival of the species.  In fact, we would not benefit from going through 100 trials before learning that the tiger in front of us may be dangerous.  We may be dead before we get to the third trial!


On April 10th, Premier François Legault stated the possibility that schools may re-open around May.  This announcement created quite a stir and many parents and teachers expressed their anger asserting that it would be impossible for them to send their children back to school – a social environment where interactions are less than two metres apart, and therefore very dangerous.


Some people were surprised by this outcry, wondering why anyone would refuse to break out of confinement on the day we’re told that it would now be safe to leave our homes and begin interacting with others.


There are two reasons for that.


First of all, deconfinement can be very stressful. As summarized in my first blog about the stress of COVID-19, there are very large individual differences when it comes to stress resistance. Some people are very resistant to stress, while others are less so.  People who are less resistant to stress will ask for extra information on safety related to the rules of deconfinement before they leave the house. On the other hand, people with high stress resistance will become impatient with all the steps that need to be taken to completely deconfine themselves, stomping their feet on the way out the door, ready to return to work or to have fun.


The second reason that could explain why one may back away from deconfinement is related to fear conditioning.  Although research has shown that fear can be generally learned from a single exposure, it is far more difficult to learn not to be afraid!


Let’s go back to our rat in the blue room.  When you bring the rat back for the first time after receiving its first exposure to an electrical shock, it will be extremely stressed and scared as soon as you walk through the door holding it in your hands.  If you put it in the cage and do not shock the rat, it will still exhibit extreme stress and fear.  If you return to the blue room the next day without administering a shock, it will still exhibit extreme stress and fear.  If you return to the blue room without delivering a shock for 15 days, the rat will slowly learn to stop being afraid.  Thus, as the days pass without any shocks, it will begin to learn that the blue room is now associated with safety.  This is called fear extinction.  The rat must learn to extinguish its fear.  And to do this, it must be exposed to the source of its fear during many trails, without receiving a shock.


So, as soon as the government announces deconfinement, people with high stress resistance are likely to start biking and engage in other activities that they did during their pre-COVID-19 lives while people with low to moderate stress resistance may continue to be afraid to go out for longer.  For these individuals, it will be essential to learn to no longer be afraid of social interactions.  In order to be able to deconfine without too much stress, these individuals will need to slowly expose themselves to social interactions and re-learn that these exposures are not the equivalent of certain death. Through re-learning that social interactions are not dangerous, they will be able to experience deconfinement without too much stress.


It will have been understood here that, in terms of stress, a gradual deconfinement will be far preferable to a rapid deconfinement.


All of the scientific data on fear learning and stress resistance has led us to understand that it is essential, when announcing a deconfinement, to be understanding of the behaviour of those around us.  It will be absolutely useless to judge a person based on their fear of going out or how quickly they walk through the door.  As I have said many times, there are huge individual differences in how people react to stress and fear and that is the beauty of human nature.  Indeed, it will be by observing people with high resistance to stress leaving their homes without suffering from negative consequences that people with lower resistance to stress will slowly learn to stop being afraid.


Once again, by sticking together, we will succeed!


  1. If you would like to know a little more about the science of fear, please listen to the first 7 minutes of Episode 2 of ‘Four Researchers and a Virus’ during which Dr. Marie France Marin discusses the mechanisms underlying the learning of fear… and safety. It’s really very good!

Text from Sonia Lupien, director of the Centre for studies on human stress