If you were shown an upside-down letter F, how would you recognize it as and "F"? In other words, how do humans recognize that a particular object belongs to a class of objects. The basic process of recognizing and categorizing objects is called pattern recognition. Three theories tend to dominant the literature for attempting to explain pattern recognition.

The first theory is called template-matching. Templates are highly detail models for patterns we might potentially recognize. We recognize a pattern by comparing it with our set of templates (stored in memory) and then choosing the exact template perfectly matches what we observe. If we don't have a template for an object, then we cannot recognize that object.

The second theory is called features-matching. Features are component parts of patterns (such as horizontal, vertical, and slanted lines). We recognize a pattern by comparing the features of that pattern with features stored in memory.

The third theory is called prototype-matching. A prototype is a representational form of the pattern. It is not a rigid, specific, concrete model (like a template). Instead, it is more like a "best guess" example of multiple varieties of the pattern. Recognizing a pattern involves comparing a pattern to the prototype. The closer the pattern to the prototype, the more likely that recognition occurs.

In this experiment, you will see a comparison of normal letters versus distorted letters and non-reversed letters (called regular) versus reversed letters. Both comparisons are combined into one experiment. These comparisons will allow you to find out if reversed letter patterns are recognized just as quickly as the normal patterns. Prototype theory says that reversed letters should be fairly readily recognized (but not as readily as normal letters). Template theory would suggest that if you have templates for the reversed letters, they should be recognized as quickly as the normal letters, however, if you don't have templates, you should be extremely slow at recognizing the reversed letters. The comparisons will also allow you to find out if normal letters (which you should have templates or prototypes for) are processed as quickly as distorted letters (which you should not have templates or prototypes for, but which have features that are common).

First you will see the following page (with no picture) while the pictures are loading.

After the pictures are loaded, the screen will look like this:

You are now ready to begin. When you slide the mouse over the small square between the words "REGULAR" and "REVERSED", the blank picture will change and present the word READY.

Then almost immediately, the letter F will appear. It can look like a normal F, a normal F that is reversed or a distorted F (the distorted F can also be reversed

The F will ALWAYS be rotated in some fashion.

Your task is to, as fast as you can, slide the mouse onto the word REGULAR (don't click) if the F (even though its rotated) is in a regular, unreversed orientation. Slide the mouse onto the word REVERSED (don't click) if the F (even though its rotated) is in a reversed orientation. As soon as you do this the screen will go blank. You then move the mouse back to the small square to do the next next trial.

The number in the small rectangle next to the word "TRIAL #" indicates how many trials you have done. You will be doing 40 trials.

At the end of 40 trials, a window will open and you will be shown your results.

When you have read and understood these instructions, Please click on the word START below, to begin.