Pattern Recognition

Look at the letters printed below.

A a   A a  A a A

It is easy to see that all of the letters are “A”.  Our cognitive processing system recognizes the patterns as “A” despite the fact that the letters differ in case (upper versus lower), font, print style (bold versus normal) and size.   This example demonstrates the power of human pattern recognition.  We are far more accurate and faster than computers at recognizing patterns as similar regardless of variations in size, coloring and shape.

Cognitive psychologists have grappled with our ability to recognize patterns in their many variations and have arrived at several theories to explain how we can do this with good accuracy.

1. Template theories state that we carry around a series of patterns or templates in our long-term memory and we match incoming patterns against these templates.  If there is a lot of similarity between the input pattern and the template pattern, then there is a match and we recognize the input as being an example of the template.  Template theories would argue that we have a template for the letter “A” that is a pretty good match for all of the letters printed above.

2. Feature theories state that we recognize patterns by their parts.  For example, uppercase letters from the English alphabet share many features; E and F both have horizontal and vertical straight lines as features.  Similarly, you may describe a friend’s face by a series of features…eye color, shape of nose and mouth and so forth.

1. Distinctive features help us to distinguish one pattern from another.  For example, an uppercase E differs from an uppercase F by the bottom horizontal line.  Thus, this bottom line is a distinctive feature that helps us distinguish between the two letters.