"Psychophysics of Reading in Normal and Low Vision" by Gordon E. Legge

Memory improvement books (promo)

Book notes:

"This book is about the role of vision in reading. It describes the influence of physical properties of text on reading performance and the implications for information processing in the visual pathways. It deals with the reading performance of people with normal, healthy vision and also people with impaired vision"

"The goal of the book is to organize and synthesize the major findings of the work in the series of 20 articles and to place them in the context of other contemporary research on vision and reading."

"Complete Citations for the 20 Articles in the Psychophysics of Reading Series:
- Legge, G. E., Pelli, D. G., Rubin, G.S., & Schleske, M. M. (1985). Psychophysics of reading. I. Normal vision. Vision Research, 25, 239–252.
- Legge, G. E., Rubin, G.S., Pelli, D.G., & Schleske, M. M. (1985). Psychophysics of reading. II. Low vision. Vision Research, 25, 253–266.
- Pelli, D. G., Legge, G. E., & Schleske, M. M. (1985). Psychophysics of reading. Ill. Afiberscope low-vision reading aid. Investigative Ophthalmology and Visual Science, 26, 751–763.
- Legge, G. E., & Rubin, G. S. (1986). Psychophysics of reading. IV. Wavelength effects in normal and low vision. Journal of the Optical Society of America, A3, 40–51.
- Legge, G. E., Rubin, G. S., & Luebker, A. (1987). Psychophysics of reading.V. The role of contrast in normal vision. Vision Research, 27, 1165–1171.
- Rubin, G. S., & Legge, G. E. (1989). Psychophysics of reading. VI. The role of contrast in low vision. Vision Research, 29, 79–91.
- Legge, G. E., Ross, J. A., Maxwell, K. T., & Luebker, A. (1989). Psychophysics of reading. VII. Comprehension in normal and low vision. Clinical Vision Sciences, 4, 51–60.
- Legge, G. E., Ross, J. A., Luebker, A., & LaMay, J. M. (1989). Psychophysics of reading. VIII. The Minnesota low-vision reading test. Optometry and Vision Science, 66,843–853.
- Parish, D. H., & Legge, G. E. Psychophysics of reading. IX. The stability of eye position in normal and low vision. Unpublished Manu script 8/89.
- Akutsu, H., Legge, G. E., Ross, J. A., & Schuebel, K. (1991). Psychophysics of reading. X. Effects of age-related changes in vision. Journal of Gerontology: Psychological Sciences, 46, 325–331.
- Legge, G. E., Parish, D. H., Luebker, A., & Wurm, L. H. (1990). Psychophysics of reading. XI. Comparing luminance and color contrast. Journal of the Optical Society of America, A7, 2002–2010.
- Legge, G. E., Ross, J.A., Isenberg, L. M., & LaMay, J. M. (1992). Psychophysics of reading. XII. Clinical predictors of low-vision reading speed. Investigative Ophthalmology & VisualScience, 33,677–687.
- Ahn, S.J., & Legge, G.E. (1995). Psychophysics of reading.XIll. Predictors of magnifier-aided reading speed in low vision. Vision Re search, 35, 1931–1938.
- Beckmann, P. J., & Legge, G. E. (1996). Psychophysics of reading. XIV. The page-navigation problem in using magnifiers. Vision Re search, 36, 3723–3733.
- Mansfield, J. S., Legge, G. E., & Bane, M. C. (1996). Psychophysics of reading. XV. Font effects in normal and low vision. Investigative Ophthalmology & Visual Science, 37, 1492–1501.
- Legge, G. E., Ahn, S. J., Klitz, T. S., & Luebker, A. (1997). Psychophysics of reading. XVI. The visual span in normal and low vi Sion. Vision Research, 37, 1999–2010.
- Harland, S., Legge, G. E., & Luebker, A. (1998). Psychophysics of reading. XVII. Low-vision performance with four types of electroni cally magnified text. Optometry & Vision Science, 75, 183–190.
- Chung, S. T. L., Mansfield, J. S., & Legge, G. E. (1998). Psychophysics of reading. XVIII. The effect of print size on reading speed in normal peripheral vision. Vision Research, 38, 2949–2962.
- Bruggeman, H., & Legge, G. E. (2002). Psychophysics of reading. XIX. Hypertext search and retrieval with low vision. Proceedings of the IEEE, 90, 94–103.
- Legge, G. E., Mansfield, J. S., & Chung, S. T. L. (2001). Psychophysics of reading. XX. Linking letter recognition to reading speed in central and peripheral vision. Vision Research, 41,725–34."

"Reading speed in words per minute (wpm) has been used to study both educational and perceptual aspects of reading (Abell, 1894; Carver, 1990; Huey, 1908/1968; Tinker, 1963;)."

"One concern with the drifting-text method is that it differs from everyday reading in the pattern of eye movements. Eye movements in static text consist of a series of fixations, typically lasting 200 to 250 ms, separated by saccadic eye movements averaging about 7 characters in length."

"Rapid Serial Visual Presentation (RSVP). Method In the RSVP method, individual words are presented sequentially at the same location’ on a display screen. The RSVP rate is controlled by adjusting the exposure time for each word. RSVP reduces or eliminates the role of eye movements in reading. RSVP was originally used in cognitive studies of word recognition in reading (Forster, 1970), and was introduced into psychophysical studies of normal and low-vision by Rubin and Turano (1992, 1994). This technique lifts a ceiling on normal reading speed imposed by the latency for eye movements; RSVP reading speeds are typically much higher than speeds for static text. For example, Rubin and Turano (1992) reported an average reading speed of 1,171 wpm RSVP text compared with 303 wpm for static text."

Why Reading Is Important - 10 Shocking Benefits of Reading (promo)

"A skimming strategy accounts for the very high reading speeds (3 to 10 times normal rates) associated with “speed reading.” For relevant data and reviews, see Just and Carpenter (1987, chap. 14), and Carver (1990, chap. 19). These authors have shown that speed reading typically amounts to sparse sampling of text, based on strategic placement of eye fixations."

"Reading speed is approximately equal to the mean saccade length divided by the average fixation time.” For example, a person who reads 300 wpm is reading 1,800 characters per minute or 30 characters per second. If they are making 4 to 5 eye fixations per second, they are advancing on average 6 to 7 new characters per eye movement. During one hour of reading they recognize about 108,000 characters."

"The visual span is the number of letters, arranged side-by-side as in text, that can be reliably recognized without moving the eyes."

"the size of the visual span is an important determinant of reading speed."

"Recall that visual-span profiles summarize letter-recognition accuracy in the portion of the visual field used for reading. Section 3.7 reviewed the evidence for a strong correlation between the size of the visual span and reading speed—both varied in a highly correlated way in response to changes in character size, contrast and retinal eccentricity."

"In a recently completed study in our lab, Ortiz (2002) also evaluated the impact of the linguistic properties of trigrams on letter recognition. He analyzed letter recognition for trigram stimuli on the horizontal midline, extending left and right of fixation. In agreement with E. M. Fine (2001), he found a word-superiority effect in both central and peripheral vision; the central letter of trigrams was recognized better in words than non-words. He also studied the influence of the frequency of occurrence in English of pairs of letters, termed bigrams. He found a bigram-superiority effect in which letters in frequent bigrams in English, such as “th”,  were recognized better than letters in infrequent bigrams, such as “qc”. Ortiz's findings imply that at least a portion of the word-superiority effect is due to enhanced recognition of common pairs of letters. In"

"This hierarchical conception of pattern recognition in reading—feature identification first, then letter identity, then word recognition—may break down when the reliability of visual information deteriorates due to non-optimal viewing conditions, poor text legibility (as in the case of peculiar fonts or handwriting), or visual impairment. Under these conditions, readers may need to puzzle their way through the text, taking advantage of lexical inference and context to interpret the words. Given adequate time, people are quite adept at reading words and text with missing letters or typos. “Can _ou rpad thi_ s_ntenee?” The idea that poor quality of visual information about letters can be circumvented by feedback from knowledge of words is embodied in some models of word and letter recognition including the influential Interactive Activation Model of McClelland and Rumelhart (1981). The point here is not to deny that top-down processes may often play a role, but to emphasize the importance of the bottom-up flow of visual information, especially under optimal visual conditions."

"Dual-Route Theory. The process of reading aloud involves transformations from written words to spoken words. A prevailing model is dual-route theory (cf. Coltheart, Curtis, Atkins, & Halter, 1993). This model makes the distinction between cognitive representations of words perse, and the semantic meanings usually associated with those word forms. This is similar to the distinction between a spelling dictionary which lists words but no meanings, and a regular dictionary such as Webster's, that also includes meaning. Dual-route theory hypothesizes two pathways from printed words to their verbal (phonological) representations. (According to the version of the dual-route model proposed by Coltheart, Curtis, Atkins, and Halter (1993), there are dual pathways from visual input of print to phonology and speech that do not necessarily require semantic processing, and there is a separate pathway from visual input to semantic analysis that does not involve phonological representations)"

"Evidence for the dual-route theory comes from experiments in cognitive psychology (for a review, see Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001). There is also evidence from studies of dyslexia centering on two extreme forms of this disorder. In one form, the reader has trouble reading irregular words such as "yacht", and tends to make regularization errors. Presumably the difficulty is due to a deficit in the lexical route, necessitating the use of the GPC rules in the nonlexical route. These individuals are normal in their ability to read pronounceable nonwords. This pure form is termed surface dyslexia. In the second extreme form, the reader has trouble speaking pronounceable nonwords, but is able to read aloud both regular and irregular words."

"This discussion raises the possibility that the lexical route dominates reading in central vision while the nonlexical route plays a relatively greater role in reading with peripheral vision. If this is the case, there would be an interaction between dyslexia subtype and reading performance in central and peripheral vision."

"People with normal vision can achieve their maximum reading speed over a 10-fold range of character sizes from about 0.2° to 2°. The smallest print size yielding maximum reading speed is termed the critical print size (CPS) and is usually close to 0.2°. This is the size of typical newsprint at a common reading distance of 40 cm. Reading speed slows down rapidly as character size decreases below the CPS. Reading speed also slows down gradually for characters larger than about 2°."

"Three structural features of the visual field play important roles in determining the size of the visual span—decreasing letter acuity in peripheral vision, crowding between adjacent letters, and decreasing accuracy of position signals in peripheral vision."

"The close connection between size of the visual span and reading speed has motivated the hypothesis that the size of the visual span is an important determinant of reading speed. We have developed a computational model that implements this hypothesis. The model shows how empirically measured visual-span profiles have a direct impact on reading speed.
It is likely that reduced visual spans play a major role in low-vision reading difficulty. This is especially true for people with central-field loss who must rely on peripheral vision for reading. Studies of reading in normal peripheral vision reveal that reading is slow, probably because of a reduced visual span."

"Is “legibility” a physical property of text, or a product of visual processing? Legibility is a good example of a psychophysical variable, such as color or bright ness, which is dependent on physical stimulus properties, but is fundamentally determined by characteristics of visual processing. Although the physical rendering of text influences the quality of text images on the retina, the ultimate assessment of legibility depends upon the properties of a participant's perceptual representation. Of course, physical distortions of text can result in perceptual representations that do not support good reading; under these conditions, legibility is low."

"Reading is characterized by saccades, averaging 8 characters in length, separated by fixations, averaging 225 msec in duration (Rayner, 1998). Both the length of saccades and the duration of fixations are under the online active control of the reader."

"The MNREAD acuity chart is a clinical and research instrument for assessing how a person's reading performance is affected by print size."

"Reading speed is measured in words per minute (wpm)."

Readlax: #1 Speed Reading App. (promo)