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Defects of the Brain


This is the second of my four blogs on the wonders of the brain. In my first blog, I outlined the main functions and features of both our conscious and unconscious minds. In this blog and another to follow, I consider some of the biases and errors of the brain before in my fourth blog suggesting ways to minimise some of these defects. This article discusses The Narrative Fallacy & Hindsight Bias, the Focusing Illusion, the Availability & Affect Heuristics and the Limitations of Expertise.

Narrative Fallacy and Hindsight Bias

Maybe the greatest defect of our working brain is the way our memory distorts what we actually experience described as the narrative fallacy. The Narrative fallacy concerns our inability to tell stories that accurately describe our past. We have a present moment experiencing self which answers the question: “How am I now?” We also have a remembering self which answers: “How was it on the whole?” Our experiencing self is pretty happy, even very happy, most of the time. The brain’s memory banks that the remembering self draws from, cannot handle the huge amount of moment by moment data. It only retains a few critical moments especially the beginning, the peaks and the end. The peaks can be good or bad but because of the negativity bias of the brain generally the bad peaks are given more weight than the good peaks. The remembering self skips a huge number of moments, most of them fairly good to good but not strong enough to be stored in out brain’s memory bank. The remembering self is the only perspective we can adopt when reflecting on our experiences. Most of the time we are on the good side of OK. However we often end up replying and also really believing: “I’m OK”. You become who you say you are. So our typical Ok reply leads us to believe and actually be less than who we truly are. We allow our distorted memories to rob us of a true evaluation and appreciation of our lives. In fact we live in illusion most of the time because the stories we tell about our lives are rarely true. The remembering self is the one that keeps score, governs what we learn from living and it is the one that makes decisions. I am my remembering self and the experiencing self, who does my living, is a stranger to me. I am my past not my present.

Our subconscious is also susceptible to hindsight where we delude ourselves that we ‘knew’ all along that certain events were going to happen or turn out good or bad. Hindsight bias adds a spice of delusion to our story making process. It is said that only the victors write history. We fill our personal stories with the threads relevant to the eventual outcome ignoring other data. Hindsight dovetails nicely with the limited capacity of our memory banks to store enough accurate data. These two faults combine to yield narratives that constantly distorts reality. We live our lives in illusion telling ourselves faulty narratives like the stories we tell about our failed marriages.

A divorced marriage is like a symphony with a screeching sound at the end. The fact that is ends badly activates our hindsight bias where the stories we tell others about the marriage largely refers to the problems caused by the partner and ignores many happy memories. We get comfort from such stories as they act to reassure us that the marriage was doomed to fail all along. We could not face the reality that in the case of some failed marriages the good moments were substantial and as significant as the bad moments.

Focusing Illusion

The focusing illusion describes our tendency to over evaluate whatever we direct our attention to. Unfortunately, nothing in life is as important as you think it is when you are thinking about it. To illustrate this let’s consider the following question: Are people who live in the Algarve happier than people in Ireland? Most people will answer yes. However studies have shown that climate and life circumstances have little effect on well-being. Natives of the Algarve who have not travelled much do not weigh their climate very much in their global evaluation of well-being. However, people who have moved there from colder climates will for a few years after the move report greater life satisfaction but this effect will have worn away after on average 4 years.

How much pleasure do you get from your car? When you try to rate how much you enjoy your car, most of the time you answer a much narrower question: How much pleasure do you get from your car when you think about it? The substitution caused you to ignore that you rarely think about your car. The result is a focusing illusion – if you like your car you are likely to exaggerate the pleasure you derive from it.

Let’s compare buying a new car with joining a sports club or a cultural group. Both will be novel and exciting at the start. You will eventually pay little attention to the car as you drive, but you will always attend to the social interactions in the groups you join or for attention demanding activities like sports or music. The focusing illusion creates a bias in favour of goods and experiences that are initially exciting and to underappreciate experiences that retain your attention in the long term. Involvement in your community is really more fulfilling than investment in goods!!

We are all familiar with the wise saying that ‘Money won’t buy you happiness’. However apart from sex nothing quite inflames our appetites than money. We can’t help focusing on money and so we evaluate it too highly. Studies have shown that higher income is associated with higher evaluation and satisfaction with one’s life (what you think your life is like) but not with experienced wellbeing (what your life is actually like moment by moment). Experienced wellbeing no longer increases with a household income over the national average household income, which was €45,000 in Ireland in 2019. And you need to earn to earn a lot less in most developing countries to attain the same experienced wellbeing. Higher income is associated with a reduced ability to enjoy the small pleasures of life. Beyond the satisfaction level of income, you can buy more pleasurable experiences and more comfortable goods but you will lose some of your ability to enjoy the less expensive goods and to spend your time on non-material things and community activities. “The best things in life are free”.

The ‘disaster cycle’ begins with the exaggerated whipping up of fear of the disaster leading to most people overweighting the possibility of the disaster before the fear dissipating with neglect of the possibility of the disaster setting in for a long period before attention is given to the possibility of the disaster and the cycle begins again. The possibility of a natural disaster is generally ignored by the populace. But when attention is given to the possibility of a disaster people tend to overweight the probability. Also, people are almost completely insensitive to variations of risk among small probabilities. A cancer risk of .001% is not easily distinguished from a risk of .00001%. This would be 6,500 cancers as against 65 in Ireland. When you pay attention to a threat, the ensuing anxiety is not proportional to the probability of the threat.

The disaster cycle has played out to script with the Covid crisis. Pandemics have occurred with regularity throughout history. In the 20th century many people in Ireland were victims of the post WW1 Spanish flu and the 1958 global flu pandemic. However for the last 50 years we have blissfully ignored the possibility of another one in Ireland. But since the Covid 19 virus has reached our shores we have persistently exaggerated its actual threat and shown very little ability to estimate its actual extent. Last year, the media persistently misreported that Italy had the worse Covid figures in Europe. Yes it had the highest actual number of cases and deaths from time to time in 2020 but it also has one of the largest populations on Europe. Little Belgium had consistently higher cases per head of population than Italy all through 2020 and proportionately suffered far more than Italy. In 2021, it was regularly reported that the worst Covid cases and deaths in the world was in India without any effort been made to put India’s high number of cases in the context of a huge population of 1.3 billion. Many parts of the media do not know how to report proportionately but they love whipping up exaggerated fears because that attracts people to their platforms.

Availability Heuristic

A heuristic is the procedure our minds often employ when faced with difficult questions. This procedure is the stock and trade of politicians. Instead of admitting we don’t know the correct answer to a question, our minds often has no trouble finding adequate though imperfect answers to difficult questions. Our subconscious has no problem cobbling together an imperfect answer with whatever is available in the mind’s memory banks. Because of the effects of the focusing illusion, much of what is in our memory banks is largely determined by the extent of media coverage which is a conduit for what people are interested in and focusing upon. People’s interest is more easily aroused by dramatic events and celebrities rather than the dull minutia of government policy. Some issues gain far too much prominence whilst others are largely neglected.

The availability heuristic is often used also in the way we make judgements. People make judgements about the probability of the events on the basis of how easy they can think of examples. The frequencies with which events come to mind are usually not accurate reflections of the probabilities of such events. Events involving high profile people are easily retrieved from memory. Frequency of celebrity divorces and political scandals are exaggerated. A dramatic accident or pandemic exaggerates frequency. Personal experience will be given more frequency ratings than things we have not experienced. Both spouses remember their own individual efforts much more clearly than they do those of their spouse. Spouses overestimated their contribution to causing quarrels although to a smaller extent than their contributions to more desirable outcomes. Many team members feel they have done more than their fair share and also feel that others are not adequately grateful for their individual contribution.

Because they are so immediate and available in our memory, some people begin to believe lies to be true when they are repeated often enough and that are coherent. Familiarity and coherence breeds a certain ease in our minds and is not easily distinguished from truth. Another trick sometimes used by certain politicians!! Indeed, you do not have to repeat an entire false sentence to make it appear true: the All Irelands of Leitrim... We pay more attention to the content rather than the reliability of messages ending up with a world view simpler and more coherent than the data justifies.

Affect heuristic

Affect heuristic is when the answer to the easy - How do I feel about it? - serves as an answer to the much harder - What do I think about it? People let their likes and dislikes determine their beliefs about the world. Instead of the hard work of getting some familiarity with the policies and viewpoints of the political parties in an election, the majority of people vote for the party that they like but not necessarily for the party that aligns with their world view. Even professionals whose career is meant to be dedicated to research into their chosen field are very influenced by this heuristic. If an economist is asked whether she thinks a company is financially sound and she also likes one of their products, this likeability will cloud her evaluation of the company.

The Limitations of Expertise

Paul Meehl, University of Minnesota, reviewed 200 studies over a 50 years period investigating the question of whether clinical predictions based on the subjective impressions of professionals were more accurate than statistical predictions made by combining scores or ratings according to a rule. Forecasting included football match winners, future prices of Bordeaux wine, longevity of cancer patients, the suitability of foster parents etc. Each of these areas entail a significant degree of uncertainty and unpredictability – low validity environments. 60% of the studies showed significantly better accuracy for algorithms. 40% scored a draw in accuracy. No win for the professional has ever been convincingly documented.

Experts try to be clever and think outside the box considering complex combinations of features. We have already seen above that the halo effect makes interviewers over confident of their first subjective impressions of the interviewees and assign not enough weight to objective job skills criteria. Simple combinations of features nearly always beat the complex thinking of so called experts. Human decision makers are inferior to the formula even when they are given the formula score. They feel they can overrule the formula because they have additional info.

Also humans are inconsistent in making summary judgements of complex info. Experienced radiologists who evaluate X-rays as ‘normal’ or ‘abnormal’ contradict themselves 20% of the time when they see the same picture a second time. One factor here, described more fully in the Anchoring effect in the next blog, is that unnoticed stimuli have a substantial influence on our thoughts and actions. A cool breeze on a hot day can make you slightly more comfortable and optimistic. Formulas don’t have these problems. They always return the same results.

Because subjective opinions cannot be trusted, professional judgements can only be trusted:

· In an environment that is sufficiently regular to be predictable

· When there is an opportunity to learn these regularities through prolonged practice

Whether professionals have a chance to develop intuitive experience depends essentially on the quality and speed of feedback during training as well as sufficient opportunity to practice. “Expertise” takes a long time to develop. Chess masters need 10,000 hours of dedicated practice – that’s 20 years of practising 2 hours a day 5 days a week or 6 years of 5 hours a day. Firefighters, nurses, professional sports stars have also stored in their memory banks valuable information for their trades. These experts know the limits of their knowledge of their trade. However, outside the operation of these skilled operations, many professionals display too much confidence in their unfounded intuitions.


All the limitations of our brains mentioned in this blog -The Narrative Fallacy, Hindsight Bias, Focusing Illusion, the Availability & Affect Heuristic and the limitations of expertise - illustrate how difficult it is for us human beings, even so called experts, to take a hard look at reality and see things as they really are. All is not lost. Our fourth blog will consider in fuller detail some ideas about how to live a less blind and deluded life. But for now remember that reports and stories are shortened accounts of what actually happens with too much importance given to highs, lows and endings. Vigilance is required about everything you read and hear. Give careful consideration about the reliability of your sources. As a general rule the more detailed, boring, nuanced and harder to read the report is the more reliable it is. The long detailed reports of the Irish Times are generally more reliable than the shorter reports of the Irish Sun. Most worrying for the future of informed public opinion, debate and even for democracy itself is the dependence of more and more people on obtaining their news from social media sources that are very unreliable.


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