5. Alerting
Alerting is an important function of attention for it provides us the ability
to prepare, maintain and be ready to process high priority signals.
There are many different types of high priority signals depending on the
situation we may be in. For example, when crossing a busy street
we are certainly on the "look out" for vehicles approaching us and can
easily adjust our pace depending on how close some vehicle may be.
It allows us to notice dangerous situations and more importantly, it allows
us to react accordingly. Plenty of studies involving letter and word
matching experiments have been conducted to investigate the alert state
(for example, see [7]). These studies have revealed that while in
the alert state, we are capable of responding faster to events however,
this ability comes with a price - it results in a higher error rate.
Studies also indicate that "the ability to maintain an alert state relies
heavily on the integrity of the right cerebral hemisphere" (as stated in
the paper). Further support for this comes from patients with
damage to this part of the brain which have trouble with alerting.
There is also evidence that the norepinephrine (NE) system
plays an important role in alerting (norepinephrine is a neurotransmitter
and has also shown to play an important role in psychological disorders
such as schizophrenia. Further information regarding NE may be found
in [11].
