The older you are, the higher your risk of dementia, as the brain naturally declines with the aging process.
Unless you continue to play a variety of high quality PC games that exercise your brain in multiple ways (different genres of games exercise your brain in different ways, eg. teamwork IQ in multiplayer online battle arenas, eye-brain-hand coordination IQ for first person shooters, multi-layered analytical IQ for real time strategy games, character template skillset permutations & combinations IQ involved in high level pvp of MMORPGs such as Ultima Online, etc ; in fact the depth of brain involvement required in the latest Street Fighter type games when played against high level opponents exercise the brain in exactly the same way as Chess or Go, but at more complex levels than in even grandmaster-level Chess or Go tournaments).
There have been many different research studies (done on a variety of game genres) that have proven that exercising your brain by playing PC games not only prevent cognitive decline, but can actually increase your IQ. The following links are research studies focused on the Portal game series, which show that playing the game increases IQ even more effectively compared to specialized IQ brain training software.
http://myweb.fsu.edu/vshute/pdf/portal1.pdf
https://www.engadget.com/2014/10/02/portal-2-improves-cognitive-ability
https://medicalxpress.com/news/2014-10-portal-cognitive-skills-lumosity.html
https://gizmodo.com/research-shows-portal-2-is-better-for-you-than-brain-tr-1641151283
https://www.popsci.com/article/gadg...gnitive-skills-more-lumosity-does-study-finds
https://www.eurogamer.net/articles/...-than-software-designed-for-that-says-science
https://www.researchgate.net/public...Lumosity_on_Cognitive_and_Noncognitive_Skills
If you're unfamiliar with how the Portal game works, see the video below (just click play, it'll start at 23:30) for a simple demo of an easy stage.
To see how far games have come in terms of graphics, see the 2018 release PC game Anthem (this isn't a trailer, but actual gameplay demo) :
Of course, to run latest games at highest graphics settings, you'll need a gaming PC, eg. you can specify the customization configuration yourself on Singapore online PC assembly services such as
http://www.googoo.com.sg/shop.asp?type=1&page=1