Articles

Types of reading disability

A longitudinal study that used imaging to compare brain activation patterns has identified two types of reading disability:

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:

To use a strategy effectively, you need to understand why it works, how it works, when it works and when it doesn’t.

For example, all students take notes — not everyone knows how to do it well. Research into the effectiveness of note-taking has found — surprise, surprise — that sometimes note-taking helps you remember information, and sometimes it doesn’t₁.

Why do we need sleep?

A lot of theories have been thrown up over the years as to what we need sleep for (to keep us wandering out of our caves and being eaten by sabertooth tigers, is one of the more entertaining possibilities), but noone has yet been able to point to a specific function of the sleep state that would explain why we have it and why we need so much of it.

There are two well-established strategies for remembering people’s names. The simplest basically involves paying attention. Most of the time our memory for someone’s name fails because we never created an effective memory code for it.

An easy strategy for improving your memory for names

We can dramatically improve our memory for names simply by:

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.

Context is absolutely critical to successful communication. Think of the common experience of being a stranger at a family gathering or a meeting of close friends. Even familiar words and phrases may take on a different or additional meaning, among people who have a shared history. Many jokes and comments will be completely unintelligible, though you all speak the same language.

Genes

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).

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.

Brain tissue is divided into two types: gray matter and white matter. These names derive very simply from their appearance to the naked eye. Gray matter is made up of the cell bodies of nerve cells. White matter is made up of the long filaments that extend from the cell bodies - the "telephone wires" of the neuronal network, transmitting the electrical signals that carry the messages between neurons.

The volume of gray matter tissue - a measure you will see cited in various reports - is a measure of the density of brain cells in a particular region.