Introduction

David Navon’s paper about the speed with which people process global and local information is extremely popular (Navon, 1977). The paper has been cited nearly 1,800 times (checked in the beginning of 2016).

The basic idea of Navon’s study is that when objects are arranged in groups, there are global features and local features. For example, a group of trees has local features (the individual trees) and the feature of a forest (the trees together).

The basic finding of Navon’s work is that people are faster in identifying features at the global than at the local level. This effect is also known as global precedence.

An example of a Navon figure is shown below. The figure has a global feature, it looks like an H. Its local feature are the many small letters X the figure is made of. People are typically quicker detecting an H than an X.

The global precedence effect is not just observed in this specific setup. For example, generally words are recognized quicker than its individual letters. Can you think of other examples?

Further reading

• Navon, D. (1977). Forest before trees - Precedence of global features in visual-perception. Cognitive Psychology, 9, 353-383.
• Navon, D. (2003). What does a compound letter tell the psychologist’s mind? Acta Psychologica, 114, 273-309.