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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:

Speed-reading techniques

Like many memory improvement courses, speed-reading programs tend to make inflated claims. Also like memory programs, most speed-reading programs proffer the same advice. In essence, speed-reading techniques involve the following components:

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.

As we all know, we are living in a time of great changes in education and (in its broadest sense) information technology. In order to swim in these new seas, we and our children need to master new forms of literacy. In this and the next three posts, I want to explore some of the concepts, applications, and experiments that bear on this.

Forget the persistent myth that everything is remembered; that our brains are video cameras whirring away recording everything, and that such 'hidden' knowledge can be brought to light by a hypnotist or alien artefact. Such things are the stuff of fantasy. Of course, there is a nugget of truth there: we can, and do, remember things we've paid no conscious attention to. Sometimes the right question can elicit memories we didn't know we had, in more detail than we imagined we could have. But for the most part, what's not noticed is not remembered. Attention is crucial to memory.

How many words do you need to learn?

An analysis of English vocabulary* has found that the first 1000 words account for 84.3% of the words used in conversation, 82.3% of the words encountered in fiction, 75.6% of the words in newspapers, and 73.5% of the words in academic texts. The second 1000 accounts for about another 5% (specifically, 6% of conversation, 5.1% of fiction, 4.7% of newspapers, 4.6% of academic texts).

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.

LBD: What is it?

Lewy Body Dementia is so called because the brains of affected people develop abnormal spherical masses of protein, called Lewy bodies, inside nerve cells. Lewy bodies are associated with Parkinson’s disease as well as dementia. Thus Lewy body dementia can refer to both Parkinson’s disease dementia and “dementia with Lewy bodies”. Lewy bodies are also often found in the brains of those with Alzheimer’s disease.

Unlike Alzheimer’s, however, dementia with Lewy bodies characteristically (but not invariably) begins with visual hallucinations.

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).

Prevalence

Vascular dementia, as its name suggests, is caused by poor blood flow, produced by a single, localized stroke, or series of strokes.

It is the second most common dementia, accounting for perhaps 17% of dementias. It also co-occurs with Alzheimer's in 25-45% of cases. Although there are other types of dementia that also co-occur with Alzheimer's, mixed dementia generally refers to the co-occurrence of Alzheimer's and vascular dementia.