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

Alzheimer’s disease, the most common form of dementia, was identified by Alois Alzheimer in 1906. Despite this length of time, there has been little progress in treatment. Why is this?

“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, Covid-19 notwithstanding. 55 million people worldwide are living with senile dementia, a number that is increasing by ten million a year as the population ages. The most common is Alzheimer’s disease, named after the German psychiatrist who first identified it in 1906. During an autopsy of 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 up of a protein called beta-amyloid. Yet since 1906, there has been virtually no progress in treating the disease, which is still a death sentence when diagnosed. Why is that?

One reason is that from the beginning, these plaques were seen as the cause of the disease, and the challenge was 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 visible plaques, while others have plaques without any symptoms. Nevertheless, the pattern has taken hold.

A second lock-in logically followed: once the cause was identified, doctors focused on finding a solution. Billions have been spent, but the few drugs that have been proposed are ineffective. All efforts have been focused on finding a solution based on a diagnosis that is no longer discussed.   The lack of results, the billions invested, and the growing number of patients without a cure are creating public pressure. The FDA, the organization that manages drugs in the United States, ends up approving drugs not because they have proven effects, but because they claim to reduce plaque. This is where the snake bites the tail, and the original mental model that the scientific community was trapped in has its catastrophic effects.

There is also a sociological dimension to the blockade. 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 everyone ignores it. A good journal selects the papers it receives by having them validated by reviewers. Who are the reviewers? Well, experts in the same field. That is, they are proponents of the dominant mental model. They have everything to lose if this model is challenged: it has made them experts and therefore powerful, with lab management, budgets, and prestige. Writing a paper that challenges the dominant model is a bit like trying to sell Thanksgiving to a turkey. Without a paper, proponents of alternative explanations have neither a budget nor a 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, this obstetrician in Vienna tried to understand why so many women in his clinic were dying in childbirth. He found that when the doctors who performed the deliveries washed their hands, the mortality rate dropped significantly. He didn’t know why, because the germ theory would be formulated 40 years later, but he knew how. And yet he could never convince doctors to do something as simple as washing their hands. Why not? Because their mental model of disease was that the cause was internal; it was due to an imbalance of humors. Washing their hands didn’t make sense to them. Again, a false mental model was blocking human progress. Semmelweis was alone and had nowhere to turn. He finally died in a lunatic asylum. The doctors were not indifferent to the fate of the victims; they were as anxious as he was to find the explanation, but they were locked into a false mental model.

We find here the same mechanisms as in the economy, where an incumbent, clinging to a dominant model on which he has built his success, blocks any progress. This 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 world’s great questions. Suppressing alternative options usually pays off a hundredfold when the dominant model is wrong. Failure to create them in parallel has disastrous consequences, with a significant loss of time, in this case for the treatment of Alzheimer’s disease, which has not made the slightest progress for decades.

Institutional logic

As Arthur Koestler and Bruno Latour reminded us in their respective books, scientists are human beings 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 it weakens the power of those who hold them. They have no interest in the evolution. So the alternative approach is to create plurality, if not in the institution, which is difficult, then at least in the environment. Then a researcher can go elsewhere and pursue a disruptive theory. 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 were ostracized by their colleagues. Kariko was eventually fired from her lab. Luckily, thanks to a friend, she found refuge in another lab and went to work for a startup (BioNTech). The vaccine was only possible because she had an alternative way out that allowed her to get around the blockade.

In the quest for innovation and progress, the stranglehold of dominant mental models must be recognized and addressed. Just as history has shown the tragic consequences of false assumptions, so too must we recognize the impact of such models in the fields of science and medicine. The way forward is to create alternative pathways for ideas to flourish, whether through entrepreneurial endeavors or the establishment of pluralistic research institutions. As we navigate the complexities of scientific progress, we must remain vigilant in fostering diverse perspectives, for it is through these avenues that human progress truly flourishes.

🇫🇷French version here.

To read more on how innovators can successfully challenge mental models, read ▶️How innovators battle entrenched mental models. Lessons from Thomas Edison’s success. 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

🔍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.