How does the brain respond to COVID-19?_Part 1

Yet another article on the Coronavirus?

Italiano English

COVID-19 is certainly the predominant topic in this particular historical moment. Let me assure you right away that I won’t be discussing the Coronavirus in the same manner as daily newspapers and news broadcasts do. They provide an essential and indispensable service but often stress the news to the point of saturation.

Instead, I will focus on COVID-19 from the perspective of the brain, specifically the mechanisms that have been triggered at the cerebral level when we suddenly found ourselves facing a pandemic, a prolonged period of quarantine, and a lack of social contact, among other things.

Given the abundance of material and the various topics I would like to delve into, I have decided to divide the discussion into multiple articles.

This first article will concentrate on how the brain perceives and judges risk and the factors that influence decision-making in different circumstances, including the COVID-19 pandemic.

For a more in-depth exploration of the neuroanatomical correlates underlying these processes, you can read also: Risk assessment in the Brain.

---

How do we assess risk?

Assessing a risky situation is a complex operation often characterised by a certain degree of uncertainty. The outcome of the evaluation is usually not entirely predictable in advance, and choosing the appropriate behaviour requires considering multiple factors.

Centuries of evolution have led our brains to refine a series of mechanisms aimed at responding quickly and effectively to the various challenges posed by the environment, ensuring the survival of the species.

For a long time, according to the so-called normative approach, it was believed that the brain, like a perfect and impartial calculator, used objective strategies and probabilistic estimates to select the most useful behaviour in different contexts, minimising risk and maximising gain.

However, this approach proved inadequate in describing how individuals assess situations and choose their behaviour in real life, focusing more on how they should do it.

In the mid-1970s, Tversky and Kahneman attempted to address this by demonstrating that people have great difficulty in making objective probabilistic estimates. Instead, they tend to unconsciously use “cognitive shortcuts” to assess situations and make decisions.

These shortcuts, known as heuristics, rely on intuitive strategies to simplify the problem space and arrive at a solution quickly. While they facilitate our lives in many situations, heuristics are not always applicable to all contexts and can often lead to serious evaluation errors, resulting in systematic deviations from reality (biases).

For example, the fallacy of small numbers leads us to believe that if we toss a coin six times, the most likely outcome sequence is the one with the most alternations between heads and tails because it is more representative of randomness.

What is overlooked, however, is that very small samples cannot contain a sufficient number of cases to reproduce the expected pattern (as larger samples do). Therefore, the probability of getting four heads and two tails in a row is the same as having different outcomes alternating six times.

The revolution of heuristics has made significant progress in understanding how people perceive reality in their everyday lives and make decisions. However, it was only towards the end of the last century that scientists began to pay attention to the emotional aspects involved in these processes, which were previously considered marginal or implicit.

Within the framework of the so-called dual-process theories, the existence of two modes of evaluation and decision-making has been hypothesised:

• SYSTEM 1, based on intuition and emotions, operates automatically and rapidly, requiring minimal processing resources, and primarily works outside of consciousness. It is independent of intelligence, cognitively inaccessible, and evolutionarily older.

• SYSTEM 2, based on proper reasoning, intervenes in a slow and controlled manner, requiring significant processing resources, and operates consciously. It is influenced by intelligence, accessible to consciousness, and evolutionarily more recent.

Finally, other aspects to consider in risk perception and assessment include the influence of one’s beliefs and past experiences, as well as each individual’s propensity, more or less pronounced, to engage in risky behaviours.

All these elements contribute to significant interindividual differences in risk perception and the choice of behaviour in different circumstances.

---

Risk assessment of COVID-19

As we have discussed, an activity that is often taken for granted and considered simple, such as making a decision in a risky situation, involves multiple processes at the brain level and requires different evaluations, both on a cognitive and emotional-affective level.

In light of these considerations, it is possible to reanalyse the various stages each of us has gone through when facing COVID-19.

The initial underestimation of the risk can be explained in terms of the availability heuristic, which is the tendency to judge the probability of an event based on how easily we can recall relevant cases or examples related to that event.

Since it was an unknown disease that initially emerged in distant locations, both the cognitive and emotional risk evaluation systems found themselves “caught off guard” and believed that the situation was not dangerous, as they had no firsthand experience data suggesting otherwise. To the extent that some preventive governmental measures (such as the suspension of flights to and from China) were considered excessive and unnecessary.

Subsequently, the identification of cases in Italy and the rapid spread of the virus was unforeseen and unexpected developments that led to a fracture in people’s reactions and opinions.

Some individuals became scared and considered the situation grave, probably relying more on the emotional and intuitive SYSTEM 1. On the other hand, others, firmly anchored to their logical and rational SYSTEM 2, continued to look sceptically at the (still low) case numbers and downplayed the severity of the virus.

It was only when the numbers also demonstrated the extent of the situation and terms like epidemic and pandemic were used, capturing media attention on COVID-19, that the entire world (or almost all of it) unanimously admitted that the Coronavirus fully belongs to the list of circumstances that seriously threaten the survival and continuation of our species.

Of course, this is a general analysis of the situation, and there are many nuances and personal considerations that have played a significant role in each individual’s evaluation of the danger of COVID-19 and, therefore, in the resulting behaviours and measures to be taken.

However, this can serve as a starting point for reflection on the difficulty of making truly objective and balanced choices and the ease with which one can fall into error, especially in anticipation of post-quarantine reopening.

In an interesting article on anxiety related to COVID-19, which you can find here, Dr Mario Mazza, a colleague psychiatrist, explains the factors that can fuel anxiety and provide some advice on how to manage it effectively.

---

BIBLIOGRAPHY:

Perna G, Caldirola D, et al: La paura, il panico e l’ansia. In: Blundo C, Neuroscienze cliniche del comportamento: basi neurobiologiche e neuropsicologiche, psicopatologia funzionale e neuropsichiatria., ed 3, Milano, 2011, Elsevier.

Tversky A, Kahneman D: Judgement under uncertainty: Heuristics and biases, Science 185(4157): 1124–1131, 1974.

Tversky A, Kahneman D: Availability: A heuristic for judging frequency and probability, Science 5(2): 207-232, 1973

Vorhold V, Giessing C, et al: The Neural Basis of Risk Ratings: Evidence From a Functional Magnetic Resonance Imaging (fMRI) Study, Neuropsicologia 45: 3242–3250, 2007.