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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).

I’ve always been interested in the body’s clocks — and one of the most interesting things is that it is clocks, in the plural. It appears the main clock is located in a part of the brain structure called the hypothalamus (a very important structure in the brain, although not one of much importance to learning and memory). The part of the hypothalamus that regulates time is called the suprachiasmatic nuclei. These cells contain genes that switch on, off, and on again over a 24-hour period, and send electrical pulses and hormones through the body. This is the body’s master clock.

If you have a numbered list to memorize, the best mnemonic strategy is the pegword mnemonic. This mnemonic uses numbers which have been transformed into visual images. Here's the standard 1-10 set.

pegs

I add two more:

Keyword mnemonic

The one mnemonic strategy that has been investigated quite extensively by researchers is the keyword mnemonic. This has been used successfully in a variety of learning areas, but its chief use has been in the area of learning vocabulary.

Most people find numbers — phone numbers, personal identification numbers, dates, and so on — more difficult to remember than words. That is, of course, why businesses try to get phone numbers that correspond to some relevant word. The system whereby this is possible — the linking of certain letters to the different digits on a telephone calling pad —is a kind of coding mnemonic. Basically, coding mnemonics are systems that transform numbers into words.

I don’t often talk about motor or skill memory — that is, the memory we use when we type or drive a car or play the piano. It’s one of the more mysterious domains of memory. We all know, of course, that this is a particularly durable kind of memory. It’s like riding a bicycle, we say — meaning that it’s something we’re not likely to have forgotten, something that will come back to us very readily, even if it’s been a very long time since we last used the skill.

Research with children has demonstrated that the ability to learn new words is greatly affected by working memory span - specifically, by how much information they can hold in that part of working memory called "phonological short-term memory". The constraining effect of working memory capacity on the ability to learn new words appears to continue into adolescence.

Our society gives a lot of weight to intelligence. Academics may have been arguing for a hundred years over what, exactly, intelligence is, but ‘everyone knows’ what it means to be smart, and who is smart and who is not — right?

Of course, it’s not that simple, and the ins and outs of academic research have much to teach us about the nature of intelligence and its importance, even if they still haven’t got it all totally sorted yet. Today I want to talk about one particular aspect: how important intelligence is in academic success.

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

Impaired vision is common in old age and even more so in Alzheimer’s disease, and this results not only from damage in the association areas of the brain but also from problems in lower-level areas. A major factor in whether visual impairment impacts everyday function is contrast sensitivity.