How mental models block innovation: The case of Alzheimer’s disease

No progress has been made to cure Alzheimer’s disease since it was first discovered in 1906. Why? Not for lack of investment, but because doctors remain stuck in wrong mental models.

“The inertia of the human mind and its resistance to innovation are most clearly demonstrated not, as one might expect, by the ignorant mass- which is easily swayed once its imagination is caught- but by professionals with a vested interest in tradition and in the monopoly of learning.” –Arthur Koestler, The Sleepwalkers

It is the great disease of the century, apart from Covid-19. 55 million people live with senile dementia in the world, a figure that is increasing by ten million per year due to the aging of the population. The most common is Alzheimer’s disease, named after the German psychiatrist who first identified it in 1906. While autopsying Auguste Deter (pictured), a recently deceased patient who had suffered severe memory loss, Alzheimer observed dense plaques in her brain. They were later identified as being made of a protein called beta-amyloid. Yet, since 1906, virtually no progress has been made in treating the disease, which still means a death sentence when diagnosed. Why is that?

Doctors stuck in the wrong mental models

One reason is that these plaques were seen from the outset as the cause of the disease, and the challenge became to eliminate them. Since then, the scientific community has been locked into this explanation. This is surprising because some people with the disease have no discernible plaques while some have plaques without having any symptoms. In spite of this, the pattern has taken hold.

A second lock-in followed logically: once the cause was identified, doctors focused on finding a solution. Billions have been invested, but the few drugs proposed are ineffective. All the effort has been focused on finding a solution based on a diagnosis that is no longer discussed.

A third lock-in now follows: with the lack of results, the billions invested, and the number of patients increasing without cure, public pressure increases. The FDA, the organization that manages drugs in the United States, ends up authorizing drugs not because they have proven effects, but because they claim to reduce the plaque. This is where the snake bites the tail, and the initial mental model, in which the scientific community has been locked up, produces its catastrophic effects.

A dominant mental model

The blockage also has a sociological dimension. Scientific research, as the sociologist Bruno Latour famously showed, is a profession, with its institutions and its political and career issues. When researchers find a result, they have to publish it. Without that, it simply does not exist. It has to be published in a good journal, otherwise everybody ignores it. A good journal selects the papers it receives by having them validated by reviewers. Who are they? Well, experts in the same field. That is to say, they are supporters of the dominant mental model. They have everything to lose if this model is challenged: It made them experts, and therefore powerful, with laboratory management, budgets and prestige. Writing a paper questioning the dominant model is a bit like trying to sell Thanksgiving to a turkey. And so the system is blocked: without a paper, the proponents of alternative explanations can have neither budget nor career. They must either submit or resign. This is how a dominant mental model can persist despite its weakness. This is also why it is not enough to be right for a new idea to be accepted by everyone.

This situation is not unlike the tragic story of Ignatius Semmelweis. In 1840 in Vienna, this obstetrician tried to understand why so many women were dying in childbirth in his clinic. He eventually found that if the doctors who performed the deliveries washed their hands, the mortality rate dropped considerably. He didn’t know why, because the germ theory wouldn’t be formulated until 40 years later, but he knew how. And yet he never managed to convince doctors to do something as simple as washing their hands. Why? Because their mental model of the disease was that the cause was internal; it was due to an imbalance of the humours. Washing their hands didn’t make sense to them. Again, a wrong mental model blocked human progress. Semmelweis was alone and had nowhere else to turn. He eventually died in a mental asylum. Doctors were not indifferent to the fate of the victims; they were just as anxious as he to find the explanation, but they were locked into an incorrect mental model.

We find here the same mechanisms as in the economy, where an incumbent, holding on to a dominant model on which he has built his success, blocks any progress. It is why the fight against monopolies has been very important since the end of the 19th century, but this fight must also exist in the field of research. We must ensure that we maintain a plurality of hypotheses on the major issues of the world. Stifling alternative options usually pays off a hundredfold when the dominant model is wrong. If they could not be created in parallel, the consequences are catastrophic, with a considerable loss of time, in this case for the treatment of Alzheimer’s, which has not made the slightest progress for decades.

The need to create a pluralistic system

As Arthur Koestler and Bruno Latour reminded us in their respective books, scientists are humans, with their beliefs and interests, and the scientific machine is an institution with its own logic. This does not mean that it cannot produce extraordinary results, as the progress of medicine has shown for many years, but it can sometimes be locked into mental models that block its progress.

In my experience, it is difficult to change the mental models of a group if this weakens the power of those who hold them. They have no interest in this evolution. The alternative approach is therefore to create a plurality, if not in the institution, which is difficult, at least in the environment. Then, a researcher can go and pursue a disruptive theory elsewhere.

That’s what happened with Pfizer’s messenger RNA-based vaccine against Covid. The researcher behind it, Katalin Kariko, was one of the few who believed in the potential of this technique for a long time. The mental model of the scientific community was “mRNA has no future”. And it blocked everything, to the point that the few who didn’t agree with it were ostracized by their colleagues. Kariko ended up being fired from her laboratory. Fortunately, she found refuge in another lab thanks to a friend, and went working with a startup (BioNTech). The vaccine was only possible because there was an alternative route out for her, which allowed her to get around the blockage.

The challenge is therefore to create exit routes for alternative theories, which is the only way to avoid the monopoly of mental models that hinders innovation. Entrepreneurship is one such exit route, as the success of BioNTech has shown. But a pluralistic public research system is also crucial. We need to create pluralistic research institutions whose purpose is to fight consensus and to generate and sustain alternative theories about the issues under consideration. Human progress depends on it.

🔍Source for this article : Where Is the Cure for Alzheimer’s? Arthur Koestler’s The Sleepwalekrs is available here. Laboratory life, from Bruno Latour and Steve Woolgar, is available here.

To read more on mental models, read ▶️How Mental Models Prevent Organizational Change: The Tragedy of the Greenland Settlers ▶️How crises disrupt our mental models and what that means

🇫🇷French version here.