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As there is such a close relation between the spoken and the written word, it is instructive at this point, as in the previous chapter, to take note of some reading studies. This is all the more true in view of the fact that these studies were un-dertaken much earlier than comparable intelligibility experiments. Visual read-ing investigations began more than a century ago with the work of the highly talented James McKeen Cattell (1860–1944).⁶ Cattell left America after his graduation in 1880 to attend lectures in Leipzig given by Wilhelm Wundt (1832–1920), the famous founder of experimental psychology, and in Göttingen by Rudolph Lotze (1817–1881). Cattell became quite enthusiastic about Wundt’s approach, and undertook a series of reaction-time experiments that brought him back to Leipzig again. Here he published his first paper (Cattell, 1885) reporting many important results on the minimal exposure time required to read letters, words, and sentences. Rather than reviewing this work in my own words, I cite here from Huey’s (1908/1968) excellent early summary of results obtained by Cattell and others. After explaining that the eyes scan the printed text in steps with pauses in which 20–30 letters may be captured, sug-gesting that “reading must go on by some other means than the recognition of letter after letter as was once supposed,” Huey wrote:

Professor Cattell early concluded, as a result of his experiments at Leipsic upon the amount which could be read in single short exposures, that we read in word-wholes and even, sometimes, in phrase and sentence wholes, and not by letters. This was evi-dently before the nature of the eye’s movement was known to him, although the dis-continuous character of the movement had already been determined by Professor Javal and his pupils. Cattell found that when single words were momentarily exposed, they were recognized as quickly as single letters, and indeed that it took longer to name letters than to name whole words, the exposures being made under conditions in which the times could be accurately measured.

5For a discussion, see Mehler, Segui, and Frauenfelder (1981).

6In 1888, Cattell became the world’s first professor of psychology, and in 1894 he was cofounder of Psy-chological Review and publisher of Science. More biographical data can be found in Poffenberger (1947).

It was found that when sentences or phrases were exposed, they were either grasped as wholes or else scarcely any of the words or letters were read. This observation was strikingly confirmed in the writer’s experiments in which sentences were momentarily exposed. Rarely were single letters read, even as forming the beginning or ends of words that were but partially recognized. The readings were of whole words, and al-most always of words connected in some sense fashion. (pp. 72–73)

Huey also pointed to the fact that words with their letters written in a vertical line are much more difficult to read than when the letters are ordered horizon-tally from left to right as usual. He concluded:

Why should not a familiar word-form be recognized and named on sight just as a house or wall is recognized and named? We do not, in the latter cases, take account of the con-stituent stories and bricks; nor of all the sticks and limbs and leaves in recognizing a par-ticular thicket or oak tree. The arrangement, the total form, is the main thing, whether in the recognition of letters, numbers, words, or objects of whatsoever sort. (p. 75)

These comments sound as if they were recently written. They are important in more than one respect. It is revealing to discover that more than a century ago scientists were able to apply tachistoscopic techniques still popular today.

The text cited here contains not only excellent avant la lettre formulations of a basic gestalt principle, but also an experimental verification, more than can be said of most early work in that field. In his description of the perception of a “vi-sual whole,” Huey used the terms arrangement and parts, still considered to be the best terms (e.g., Uttal, 1988).

It is highly remarkable that half a century before the phoneme was launched as the basic unit in speech perception, the grapheme as its visual counterpart was, on experimental grounds, already firmly rejected as the basic unit in read-ing. This is the more surprising as the independence of graphemes is obvious whereas the independence of phonemes is not.

It took nearly half a century before word reading received new attention, this time, again, as a result of quite surprising observations. In 1935, Stroop pub-lished the results of what has since come to be considered a classic experiment.

He presented his subjects with a list of color names printed in color and found that they could name the colors of the words much more quickly if the color of the print agreed with the color name represented by the word than if it did not.

This so-called Stroop effect indicates that the subjects, although requested not to read the words, could not avoid this, resulting in response retardation and er-rors. The effect demonstrates nicely the “automatic” tendency to see and read words as unities. Experiments have also confirmed that words are read more quickly when they are more familiar.

The priority of words over letters was additionally verified in a quite different approach by G. M. Reicher (communicated by Miller, 1991). He presented his subjects with visual stimuli such as “HEAR” and “AEHR” and asked them to re-port whether the final letter was D or R. Accuracy was significantly better for meaningful words than for nonsense words. Apparently, the subjects could not avoid reading the entire word in responding to the question. Wheeler (1970) extended this experiment by comparing reaction times required for recognizing individual letters and words. He concluded:

Performance on words was consistently better than on single letters in all cases.… It seems appropriate to stop trying to explain away the phenomenon and, instead, to consider the implications for models of the human recognition system.

The major conclusion to be drawn from the strength and persistence of the word superiority effect … is that word recognition cannot be analyzed into a set of inde-pendent letter recognition processes. There is an interaction among the letters such that the context of the other letters of a meaningful word improves recognition despite the control of letter redundancy. (p. 78)

These experiments demonstrate that there is an irresistible inclination to see familiar words as perceptual wholes rather than as strings of letters. We have noted in the previous chapter that learning the individual letters is an essential part of learning to read. We have to know the letters in order to extend our vo-cabulary. The reader will need the letter mode to discover that MCMXCVI in Roman numerals represents the same year as 1996 in Arabic numerals. How-ever, as soon as we are familiar with the “pictures” of words, particularly the fre-quent ones, we grasp them as unities. This is the most efficient way of reading.

Kolers (1972) pointed out that if a reader had to see every letter one by one in order to read a word, reading rate would be limited to roughly 35 words per min-ute, whereas good readers can go as fast as 300 words per minute.

The year 1996 when written in Roman numerals also demonstrates that the assumption of independence in reading letters of the written language is not as rigid as it might seem to be. We can evaluate the first C only in combination with the following M, the X only in combination with the following C. Mutual de-pendencies occur particularly in languages with substantial deviations from the ideal phoneme–grapheme congruence, as is the case for English. For example, in the word phone we need the h to know that the sound of the initial consonant is /f/, not /p/, and we need the e to know that the vowel is /o/, not /]/, and to rec-ognize the additional peculiarity that the final e is not pronounced. These ambi-guities are so numerous in English that foreigners (and apparently many native speakers, too!) learning to read English need the phonetic transcriptions of the dictionary to tell how the words are pronounced.

The role of eye movements in reading has recently been extensively studied.

As the quotation from Huey showed, the fact that the eye jumps (makes “sac-cades”) during reading from one fixed point to the next, rather than moving continuously, was already known in the beginning of the 20th century. These saccades correspond in normal reading with a span of about seven letters, with a standard deviation of three letters (for a review, see O’Regan, 1990). This means that, on the average, our eyes move from word to word. The average du-ration of the successive fixations is 200–250 msec. It is clear that reading would be greatly delayed if our vision were restricted to the text segment covered only by the fovea, the area of sharpest vision.

Rayner and Bertera (1979) investigated the reading rate of sentences as a function of the number of letters (including spaces) simultaneously presented to the reader. They used a computer-controlled cathode-ray tube that pre-sented an adjustable number of letters around the fixation point of the eyes, to be called the window; the more remote letters were masked. The window jumped synchronously with the monitored eye movements. The curve in Fig.

5.10 shows that reading rate increased rapidly with the width of the window, up to an asymptote of about 30 letters. This indicates that remote letters, as many as 14 to the right of fixation, although only vaguely seen, still contribute to word recognition in reading.⁷

An interesting question is whether the access code employed in reading is purely visual or whether a first conversion into speech is involved. In other words: Is reading an achievement on its own or is it actually silent speaking?

Children learn to read by pronouncing words in order to grasp the correspon-dence between phonemes and graphemes. Is this only an aid to the teacher for evaluation and correction, or is it an essential stage of the process, which con-tinues subliminally in silent reading?

This question has concerned many investigators. By introspection, it may appear that we have the experience of pronouncing silently words we read. But this does not mean that the phonological route is necessary. Just as we see and interpret our surroundings directly, whether the furniture in a room or the traf-fic in the street, without any speech involvement, it is possible that we are able to see and grasp the meaning of written words and sentences without actually saying them. Moreover, the reading rate of a skilled reader can be so high, and his or her scanning of the text may be so haphazard, that the process may differ fundamentally from listening to a speaker. Experiments designed to address the

7For the identification of parafoveally presented letters, see O’Regan, Lévy-Schoen, and Jacobs (1983).

question certainly have not led to unequivocal conclusions (cf. Besner, 1987;

Downing & Leong, 1982). One gets the impression that the answer strongly de-pends on the experimental task involved. The divergence of conclusions based on different experimental approaches to the same question suggests that there is no one perceptual strategy. Probably, the visual route exists in addition to the phonological route, and the reading process can use both depending on the re-quired efficiency. The opposite case, considering whether we have to spell words in order to understand them, is more easily answered because being able to read is not essential for speech comprehension. Nevertheless, literate speak-ers and listenspeak-ers like to know how words are spelled, and, as we have seen, spell-ing may play an essential and almost automatic role in word-recognition experiments using listeners who are also trained in reading.

We have already mentioned the contrast between the “continuity” of words in speech and the clear divisions between words in written language. The “co-hesion” of the phonemes constituting a spoken word is much greater—one might say much more basic—than of the letters in a written word. However, we should not forget that written text contains ambiguities that are not present in the spoken version. For instance, in the printed sentence “wearetrainingateam”

the string segments “wear,” “rain,” and “gate” can be recognized first and keep us from decoding the sentence, “we are training a team,” whereas such uncer-tainties are entirely absent if we hear the sentence pronounced.

FIG. 5.10. Reading rate of text as a function of window size (based on data from Rayner &

Bertera, 1979).