Debate Between Cross-Sectional and Longitudinal Studies on Cognitive Aging

The discourse has once again turned to a feverish discussion of cognitive decline. Which 2024 US Presidential candidate has it worse? What does that mean for the campaign and for the Presidency in general?

In this episode of The Studies Show, your rapidly-ageing hosts look at some of the research on cognitive ageing and cognitive decline. What happens when you give cognitive tests to people of different ages? Do those tests actually matter? They then ask whether there’s a chance that the received wisdom about cognitive ageing is wrong, and that maybe they can hold onto their precious faculties for just a little longer…

We’re proud to be sponsored by Works in Progress magazine. If you’ve ever been interested in the process of science, the history of technology, and how to use policy to speed up human progress, then WiP is the magazine for you. Their new February 2024 issue is out now.

Show notes

* Example of a recent article on Joe Biden’s cognitive decline; example of the same for Donald Trump

* The above is Figure 1 from this 2019 review on cognitive ageing. The three panels show: levels of fluid reasoning ability at different ages; levels of crystallised knowledge at different ages; the prevalence rate of dementia in different age ranges

* Yes, the Woodcock-Johnson Tests exist

* 2016 study showing similar patterns of cognitive ageing in Tsimane forager-farmers in the Bolivian Amazon

* 2012 review on cognitive ageing; see Figure 1 for the “Fortune 500 CEO” graph described in the podcast

* Study on how IQ-type tasks and more practical tasks change together in old age

* Study on cognitive ageing and susceptibility to scams

* Tom’s IEEE Spectrum article on how robots learn

* Older (2004) article on cognitive ageing; Figure 1 is a useful comparion between cross-sectional and longitudinal studies

* Book chapter with a useful discussion on when cognitive ageing begins

* 2022 Nature article on “brain charts for the human lifespan”

* Systematic review from 2010 on interventions for cognitive decline

* 2019 meta-analysis of “real-world” intervention studies

* Remarkably biased US politics interview about Biden and Trump and their respective mental capacities

Credits

The Studies Show is produced by Julian Mayers at Yada Yada Productions.

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit sciencefictionspod.substack.com/subscribe