"Pay attention" is a phrase we expect to hear in the classroom. But what exactly is attention?
In fact, there are multiple types of attention driven by a variety of different - and quite intuitive - processes. We all know that going supermarket shopping when we are hungry will result in us spending more. This is because our attention is driven by our internal (or "endogenous") state of hunger. A more academic example would be becoming engrossed in a book. Your motivation for attending to the story may be to find out how the lead character completes their quest.
An alternative to this internal motivation is an external (or "exogenous") stimulus, the classic examples of which are hearing your name called or having your attention drawn by a loud bang.
Interestingly, there are age-dependent differences in attention. For example, scientists have shown that exogenous attention develops before endogenous attention. This means young children do not pay attention to internal stimuli in the same way as older pupils, so find tasks requiring it extremely difficult. They can still pay attention, but will do so more successfully if external stimuli are used.
Of course, as well as different drivers of attention, there are different types of attention, including selective, sustained and divided.
Selective attention is when the limited attention available is paid to one stimulus in the presence of distractions - for example, concentration on a telephone conversation rather than background chatter. This process generally improves with age, although changes are limited after the age of nine.
Similarly, sustained attention - where attention remains focused on a particular stimulus for some time - has been found to reach adult levels by about the age of 10, with particular improvement between five and nine. That is not to say there is no development after this age; certainly, evidence from neuroscience suggests there is.
Neuroscientists have shown that the brain's frontal lobe, thought to be critical for attention, undergoes substantial changes during adolescence, so we might expect concentration skills to develop more fully during this period. This is most likely to be the case for divided attention, which is perhaps the most demanding kind and involves splitting attention between two tasks simultaneously.
Research has found that various factors, some beyond the control of the teacher, can improve attention. A recent study shows that altered lighting and colour temperature can improve measures of attention. Additionally, research into drugs such as Ritalin suggests they can improve attention in individuals with attention-deficit hyperactivity disorder and, more controversially, in healthy individuals.
However, there are simple things a teacher can do to help pupils pay attention to the right things - for example, explaining tasks in a step-by-step fashion to avoid them missing information.
A now-famous example of inattention blindness is the video that asks viewers to count how many times a basketball is passed between players dressed in white (http:bit.lycBDqbU). Viewers often fail to notice the arrival of a person dressed in a gorilla costume. This phenomenon is linked to activation in the frontal lobe and specifically the prefrontal cortex, and is why younger people tend to show greater inattention. If you give students too many stimuli at once, they could be paying attention but still be blind to a significant amount of what you tell them.
Teachers can also keep distractions to a minimum. For example, be careful about letting one group of pupils listen to music while another researches a composer on the internet. The exogenous stimulus - the music - will grab the attention of pupils working on the other task.
Attention is a complex set of processes and effectively a gate on what reaches us. If we do not attend to something we cannot learn from it, and yet there is a balance between attending to one thing and still "seeing others". This balancing act will alter with development and that makes ensuring children pay attention quite a challenge.
Dr Ellie Dommett is a lecturer at the Open University and co-author of the "Learning and The Brain Pocketbook"
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