The mechanisms of perceptual learning include attention weighting, imprinting, differentiation, and unitization. With attention weighting, perception becomes adapted to tasks by increasing the attention paid to important dimensions and features.

With imprinting, special receptors are developed that are specialized for specific stimuli.

With differentiation, stimuli that were once indistinguishable become psychologically separated.

With unitization, tasks that originally required detection of several components are accomplished by detecting a single construct (How Perpetual Learning Works, n.d.).

There have been several studies done that have shown that the effects of stimulus exposure time on reaction time. It has been shown that simple reaction time became shorter with increased exposure time. In other words, the longer that someone is exposed to a stimulus the shorter that their reaction time to the stimulus will be. It has also been shown that just being exposed to a stimulus one time increases the reaction to it when exposed to it again. Once exposed to something if you are put into that same situation again you expect to have the same thing happen and thus you are expecting a reaction (Learning, 2008).

Learning is a continuous reaction to stimuli that is around us. Simple stimulus learning is only one type of learning. We are constantly being exposed...

If we are continuously exposed to the same thing over and over again we eventually go through the process of habituation. Once we become used to certain stimuli and we no longer have reactions to them, we are then opened up to react to new stimuli. If we had to react to every stimulus that we were exposed to on a daily basis we would not be able to get anything else done. It would be a very noisy and over stimulating world that we would live in. We would not be able to cope with having to react to every stimulus that we came into contact with.
Human beings begin the learning process at a very early age and continue to learn for the rest of our lives. Understanding the learning process and what it is that we go through in order to learn new things also helps us to understand why some people have trouble learning while others seem to go about it naturally. Learning is a fascinating process that we go through all the time whether we realize it or not.

References

How Perpetual Learning Works. (n.d.). Retrieved March 29, 2009, from Institute of Perceptual

Learning Web site: http://www.perceptuallearning.com/plearn.php

Learning. (2008). Retrieved March 29, 2009, from MSN Encarta Web site: http://encarta.msn.com/encnet/refpages/RefArticle.aspx?refid=761556088