That's good, thanks, but it doesn't really address the original question regarding games for example. Also what if dementia already has some effects early in life, just more subtle. So for example early stages could be more difficulty concentrating, variations in attention, or greater difficulty in internalizing ideas, memorization, or recall. Then those who would later show typical symptoms of dementia later in life would be more likely to end education early just because they had more difficulty with it than their peers.
Hi Mzs, thats a really good question and you're right I don't directly address it.
Basically it's impossible to examine for that at the moment because 'games' etc would rely on a person's recall of, say, how much they did the cross-word, that sort of thing whereas education is verifiable and, in this case, statistically meaningful.
Regarding onset of dementia.
There are early-onset dementias that can start from the late 40's to 60s. These are usually of a genetic variant (For example, 2 copies of ApoE4 gene, Amyloid Precursor Protein or a presenilin mutation, or Down's syndrome). Diabetes is a big risk factor as well.
There are also a number of dementias that are of early onset that are not Alzheimer's such as Frontotemporal dementia and Semantic Dementia which are awful diseases and it's terrible to watch patients so young with such severe pathology.
>Also what if dementia already has some effects early in life, just more subtle.
Just to focus on the most common dementia, Alzheimer's -
We know that it doesn't have more subtle effects early on. When you start to develop it, you start to develop it. The following things are the features of Alzheimer's, in order of progression:
- Memory
o Impaired anterograde episodic memory
o delayed recall of stories
o ‘Sparing’ of Working memory
- Attentional and executive deficits
o poor concentration
- Language and Knowledge
o Impaired semantics
- Visuospatial and perceptual disabilities
But It definitely is not apparent so early for example in people at 20 or 30 years of age.
We know this because brain biopsies from post mortems of young people don't show the neuronal loss, amyloid plaques and 'tombsones' of Tau protein tangles on histology which is pathognomonic of the disease.
In fact, Education seems to be so important at preventing the march of the disease not because higher levels of brain activity somehow decrease deposition of the characteristic histology findings, but because increased education increases so-called 'cognitive reserve', meaning that even when the damage starts to occur, the person is still able to function at such a high level because the decline in global cognitive capabilities has not yet been so great that the characteristic signs and symptoms have begun to manifest.
Could you argue cause vs effect with regard to education and cognitive reserve? Sure, and I haven't examined the data closely enough with regard to education to know how or if they controlled for it. However I have read extensively from the original literature with regard to the origins and pathogenesis of the disease and trust that something that is trumpeted at being a major factor in delaying the development of AD, by way of the quality of the reporting literature (Lancet, NEJM, Nature and Nature Medicine) to not have been missed after extensive peer review over the course of several decades (?the argument from authority? I feel it is well enough established to be fact)
Thanks, I did not know about the results from biopsies of young and that was a good point about the quality of data just asking about how much people remember doing something like puzzles and games. I really enjoy this site thanks to the thoughtful comments, have a good one.
From [1] Education > 15 years (cf. <12) has the lowest relative risk (0.48) of developing Alzheimer's of all investigated interventions
Patterson, C. et al. CMAJ 2008;178:548-556 (for those that can, DOI: 10.1503/cmaj.070796 )