The Seattle Longitudinal Study of Adult Intelligence has followed a group of more than 5000 people for well over four decades. The program began in 1956 and participants have been tested across a whole gamut of mental and physical abilities at seven year intervals since that date.
The study has found:
Let’s talk about the cognitive benefits of learning and using another language.
In a recent news report, I talked about the finding that intensive learning of a very novel language significantly grew several brain regions, of which two were positively associated with language proficiency. These regions were the right hippocampus and the left superior temporal gyrus. Growth of the first of these probably reflects the learning of a great many new words, and the second may reflect heavy use of the phonological loop (a part of working memory).
Neurogenesis — the creation of new brain cells — occurs of course at a great rate in the very young. For a long time, it was not thought to occur in adult brains — once you were grown, it was thought, all you could do was watch your brain cells die!
Adult neurogenesis (the creation of new brain cells in adult brains) was first discovered in 1965, but only recently has it been accepted as a general phenomenon that occurs in many species, including humans (1998).
Several genes have been implicated in Alzheimer's, but the big one is the e4 allele of the ApoE gene (on chromosome 19). This variant is found in about a quarter of the population.
Having it doesn't mean you are foreordained to develop Alzheimer's, but it certainly increases the risk substantially. The risk goes up considerably more if both of your genes are the e4 variant (remember you inherit two: one from each parent).
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.
Most mnemonic strategies are based on imagery. There is no doubt that imagery can be an effective tool, but there is nothing particularly special about imagery. The advantage of imagery is that it provides an easy way of connecting information that is not otherwise readily connected. However, providing verbal links can be equally effective.
Most people believe that an adult learner can't hope to replicate the fluency of someone who learned another language in childhood. And certainly there is research to support this. However, people tend to confuse these findings - that the age of acquisition affects your representation of grammar - with the idea that children can learn words vastly quicker than adults. This is not true. Adults have a number of advantages over children:
There are many memory strategies that can be effective in improving your recall of text. However, recent research shows that it is simplistic to think that you can improve your remembering by applying any of these strategies to any text. Different strategies are effective with different types of text.
In October I reported on a study that found older adults did better than younger adults on a decision-making task that reflected real-world situations more closely than most tasks used in such studies. It was concluded that, while (as previous research has shown) younger adults may do better on simple decision-making tasks, older adults have the edge when it comes to more complex scenarios. Unsurprisingly, this is where experience tells.