Articles

Most cognitive processes decline with age

It does appear that most component processes of cognition decline with advanced age if the difficulty level is sufficiently high. For example, the following processes have all shown age effects:

Humans are the animals that manipulate their cognitive environment.

The evidence that diet, physical exercise, and mental stimulation all help prevent age-related cognitive decline and reduce the risk of mild cognitive impairment and Alzheimer’s, is now very convincing.

Studies of mice and (rather intriguingly) beagles, have provided evidence that ‘enriched’ environments — ones that provide opportunities for regular exercise and mental stimulation — reduce or prevent age-related cognitive decline, and reduce the risk of Alzheimer’s.

Humans have a long tradition of holding genes responsible for individual differences in behavior (of course, we called it "blood", then, or "family"). In the 20th century, a counter-belief arose: that it was all down to environment, to upbringing. In more recent decades, we have become increasingly aware of how tightly and complexly genes and environment are entwined.

Coding mnemonic

Coding mnemonics are used for encoding numbers. Because words are much easier for most of us to remember, a system that transforms numbers into letters is one of the best ways for remembering numbers — as seen in the modern innovation of encoding phone numbers into letters (0800-ANSETT).

A coding system is very useful for remembering numbers, but it must be said that few people have sufficient need to memorize long numbers to make the initial cost of learning the code acceptable.

Prevalence of dementia

Dementia is estimated¹ to afflict over 35.5 million people worldwide -- this includes nearly 10 million people in Europe, nearly 4.4 million in North America, nearly 7 million in South and Southeast Asia, about 5.5 million in China and East Asia and about 3 million in Latin America.

We all like simple solutions. However much we may believe we are ‘above’ black-&-white dichotomies, that of course we understand that every situation is complex, nevertheless we have a brain that can only think of a very very few things at once. So it's unsurprising that we are drawn to solutions that can be summed up simply, that can fit comfortably within the limitations of working memory.

One of my perennial themes is the importance of practice, and in the context of developing expertise, I have talked of ‘deliberate practice’ (a concept articulated by the well-known expertise researcher K. Anders Ericsson). A new paper in the journal Psychology of Music reports on an interesting study that shows how the attributes of music practice change as music students develop in expertise. Music is probably the most studied domain in expertise research, but I think we can gain some general insight from this analysis. Here’s a summary of the findings.

I was listening on my walk today to an interview with Edward Tufte, the celebrated guru of data visualization. He said something I took particular note of, concerning the benefits of concentrating on what you’re seeing, without any other distractions, external or internal. He spoke of his experience of being out walking one day with a friend, in a natural environment, and what it was like to just sit down for some minutes, not talking, in a very quiet place, just looking at the scene.

In the mid-seventies, Raugh and Atkinson had remarkable results using the keyword method to teach Russian vocabulary to college students. While later studies have not tended to find such dramatic results, nevertheless, a large number of studies have demonstrated an advantage in using the keyword mnemonic to learn vocabulary.

Some researchers have become huge fans of the strategy. Others have suggested a number of limitations. Let’s look at these.