Virtual Typography

5.3

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Job:01212 Title: Basics typography (AVA)

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Typography and the process of reading: 5.3 Saccadic eye movements

5.2 Serial and parallel letter recognition 5.4 The prospective interpretation of text contents

Saccadic eye movements

Both the Bouma hypothesis and the parallel letter

recognition theory are supported by the discovery of

saccadic eye movement. It has been known since the

late nineteenth century that the scanning of text does not

follow a smooth pattern. But where the eyes come to a

halt and how long they rest on certain points remained

unclear for many decades. Precise evidence for the quick

and unconscious eye movement involved in reading –

the ‘saccades’ – could only be established thanks to

the increasing accuracy of eye-tracking technologies,

which now allow us to measure and monitor the motion

of the reader’s eyes with great precision. Now we know

for certain that human eyes jump from word to word,

sometimes from syllable to syllable, rather than from

letter to letter. The fi xation period is the time span during

which the eyes do not move. Fixation spans constitute

an interruption of the scanning process and provide

important evidence on how text is perceived. Whilst

words are fi xated for 200–250 milliseconds, the jumps

of the reader’s eyes between words (the saccades) take

only about 20–35 milliseconds. Whether the Bouma

model deserves more credibility than the parallel letter

recognition theory or vice versa, or if a combination of

both models would be most appropriate, remains a

highly contentious issue. Either way, people read word

by word.

Job:01212 Title: Basics typography (AVA)

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