Nostalgia can turn toxic if it makes people think world has gotten worse: Charan Ranganath

Age has become a key issue in the US presidential election, with not just the media but even the top two contenders (Biden is 81 and Trump 77) taking potshots at each other. In a recent oped for The New York Times, memory researcher Charan Ranganath points out that an individual’s age does not say anything definitive about the person’s cognitive status. He should know. The Indian-origin neuroscientist, who is currently director of the Dynamic Memory Lab at UC Davis, has spent decades studying how memory works. It’s also the subject of his latest book, ‘Why We Remember’. In an interview to Sunday Times, he shares his insights

In your article, you point out that everyone forgets. But then why do we remember some things and not others...
Memory is ultimately the process by which our brains and behaviour are changed by past experiences. I study episodic memory, which is the ability to recall past events. The episodic memories that we hold onto tend to be the ones that, from an evolutionary perspective, are most relevant to hold onto for the future. This would correspond to emotionally significant events as well as experiences that are new or surprising. Conversely, the events that are forgotten tend to be ones that are very repetitive and bland. Memories compete with each other, so a memory of something that you have done very often — such as inattentively placing your keys somewhere — is the one you are likely to forget. The problem is that you must remember where you put your keys today, but that memory must compete with memories of all the other places you have put down your keys.

Dementia and Alzheimer’s Disease (AD) is a concern in India given the rise in the number of patients. What insights has your research on Alzheimer’s thrown up so far?
Part of the reason for the increasing numbers of AD patients is because, on average, in many countries people are living longer. In my own lab, we are very early in the stages of our Alzheimer’s Disease research collaborations. Right now, there are a number of efforts to identify people who are at risk for conversion so that treatments can be administered early enough to prevent the spread of the disease throughout the brain. The biggest discovery in AD research is that the brain changes that happen in the disease can happen long before people have noticeable memory deficits.

Renowned public intellectuals have attributed the ongoing wars in Ukraine and Palestine to the ‘burden of memory’, a consequence of remembering too much as a nation. Is nostalgia — especially collective nostalgia — dangerous?
Nostalgia can be dangerous, but it doesn’t have to be. My parents, for instance, tend to get nostalgic about their childhood years in India and their early time in the US. They are also nostalgic about my childhood and my brother’s. I think this is characteristic of the way memory works — people tend to recall their formative years often, and with age, we tend to view the past in a more positive light, even reminiscing about the difficulties and challenges in a positive way. Reflecting on positive memories of the past can be helpful for our mental health by improving our mood, giving us optimism, and reminding ourselves of our positive characteristics. But nostalgia can turn toxic if it leads people to think that the world has gotten worse. People are often unaware of their memory biases, and they overlook the challenges and difficulties they have experienced in the past, which gives the illusion that things have gotten worse. Authoritarian leaders weaponize nostalgia by providing selective narratives of history to give the impression that the world used to be better, and now it is getting worse. The blame is then shifted to outgroups and used to justify terrible actions. What people miss is that collective nostalgia is almost always based on incomplete or incorrect historical narratives. If any politician tries to tell you that things used to be good and now they are bad, you should be immediately suspicious. Giving credence to these kinds of leaders is ultimately no different than falling for a con artist and giving them the keys to your house.

In the digital age, when one can google things, why should we remember?
Ha. Albert Einstein is quoted as saying, “Never memorise something that you can look up” (though it is not clear that the collective memory of that quote is accurate!). Research shows that people who use the web a lot forget the facts they look up but remember the source where they came from. I am all for outsourcing tedious tasks to external devices, so we can focus on what matters to us — like remembering the time you spend with the people you care about.

How do we get our brains to work faster than ChatGPT (asking for a friend)?
I’m not sure we can work faster than ChatGPT, but we are more flexible, efficient, and creative. Generative AI requires vast amounts of data and the carbon footprint is huge. Human brains use very little energy and are capable of learning from single instances. For instance, if you eat at your favourite restaurant and have a terrible meal that was made by the new chef, you won’t go back. It doesn’t require a large amount of trial and error to figure that out, but it does for ChatGPT. And we can create art, literature, and music that is more unique and imaginative than ChatGPT because we each have unique experiences in the real world. AI will pose real threats to people who excel at conventional work. But if you seek out diverse groups of people and expose yourself to a diverse range of unconventional intellectual and artistic influences, you can stay relevant in the age of generative AI.