From ink to insight: The science of written language

saccades

rapid eye movements that quickly shift gaze from 1 focal point to another

fixations

brief, pauses where gaze locks onto specific location so the visual system can process high-resolution details

regressions

backward eyemovements

• makes up 10-15% of all eye movements during reading

process of reading

combination of saccades, fixations and regressions

typical fixation frequency during reading

3 Hz - 3 fixations per second

effect of word characteristics on fixation

Common (high-frequency) words receive shorter fixations than rare words.

When is visual information acquired during reading?

during fixation

typical saccade during reading

about 20–50 ms

How long do fixations last during reading?

typically 150 ms to >1 second, depending on word difficulty and context.

What affects the number of regressions in reading?

context difficulty and ambiguity—harder or less predictable text more regressions

What is the perceptual span during a fixation in reading?

process 3-4 characters to left and up to 15 on right using peripheral vision

factors influencing perceptual span and eye movements

Language direction, reading skill, and text difficulty

dual route model

3 routes

1. lexical semantic - word>meaning

2. lexical non-semantic - word recognition without meaning access

3. GPC - grapheme-to-phoneme - sounding-out

GPC rule system

applying known rules of language sounds (phoneme) to letters and letter combinations (grapheme)

acquired surface alexia

reading disorder - sound out regular words but struggle with irregular words due to damage to the lexical reading route.

Acquired Phonological Alexia

reading disorder where patients can read familiar words but struggle with nonwords due to impairment of GPC route.

when do you recognise single letters faster

presented in familiar words