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The limitations of working memory have implications for all of us. The challenges that come from having a low working memory capacity are not only relevant for particular individuals, but also for almost all of us at some points of our lives. Because working memory capacity has a natural cycle — in childhood it grows with age; in old age it begins to shrink. So the problems that come with a low working memory capacity, and strategies for dealing with it, are ones that all of us need to be aware of.

Short-term vs long-term memory

Working memory is a relatively recent term, a refinement of an older concept - that of short-term memory. Short-term memory was called thus to distinguish it from "long-term memory" - your memory store.

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.

I recently reported on a finding that memories are stronger when the pattern of brain activity is more closely matched on each repetition, a finding that might appear to challenge the long-standing belief that it’s better to learn in different contexts. Because these two theories are very important for effective learning and remembering, I want to talk more about this question of encoding variability, and how both theories can be true.

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.

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.

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.

Retrieval practice, as its name suggests, is a simple strategy that involves retrieving the target information one or more times prior to testing. It is not the same as repetition or rehearsal! The idea is not to simply repeat the correct information, but to try and retrieve it. Feedback as to the correct answer may or may not follow.

What is neurogenesis?

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).

To celebrate Māori Language Week here in Aotearoa (New Zealand), here's some mnemonics to help you learn 25 common words in te reo. These use the keyword mnemonic. Keywords are written in italics.

aroha (love), an arrow in the heart

awa (river), a water flowing

hīkoi (walk), hike

hui (gathering, meeting), a lot of hooey is spoken at meetings!

iti (small), itty bitty