Sarah J. White

Mindblind Eyes: An Absence of Spontaneous Theory of Mind in Asperger Syndrome

Diverting Asperger Deficit Placement of Asperger syndrome within the family of autism spectrum disorders (ASD) has always been a bit uneasy; although people with Asperger syndrome do exhibit the core impairments in social interaction and communication that are characteristic of ASD, they nevertheless perform well on tests that are thought to assess the ability to mentalize or to possess Theory of Mind skills. One of the classic tests of mentalizing ability is the false-belief task, in which subjects must be able to represent their own beliefs (true) and anothers beliefs, which are false because they have not been given complete information, such as not having seen the transfer of a piece of candy from one drawer to another. People with Asperger syndrome succeed at the verbal form of the false-belief task, yet Senju et al. (p. 883, published online 16 July) show that this is owing entirely to their having learned how to cope with an existing and still demonstrable deficit in an implicit version of the false-belief task. That is, the core impairment is present, but conscious and explicit learning allows them to compensate. Asperger syndrome individuals do not pass a nonverbal false-belief test. Adults with Asperger syndrome can understand mental states such as desires and beliefs (mentalizing) when explicitly prompted to do so, despite having impairments in social communication. We directly tested the hypothesis that such individuals nevertheless fail to mentalize spontaneously. To this end, we used an eye-tracking task that has revealed the spontaneous ability to mentalize in typically developing infants. We showed that, like infants, neurotypical adults’ (n = 17 participants) eye movements anticipated an actor’s behavior on the basis of her false belief. This was not the case for individuals with Asperger syndrome (n = 19). Thus, these individuals do not attribute mental states spontaneously, but they may be able to do so in explicit tasks through compensatory learning.

Raeding Wrods With Jubmled Lettres There Is a Cost

Two years ago, a widely circulated statement on the Internet claimed that resarceh at Cmabrigde Uinervtisy fuond that sentecnes in whcih lettres weer transpsoed (or jubmled up), as in the setnence you are now raeding, were easy to read and that letter position in words was not important to the ability to read successfully. In actuality, the statement was a hoax in that no such research had been conducted at the University of Cambridge (see http://www.mrc-cbu.cam.ac.uk/personal/matt.davis/ Cmabrigde/). We report here results from a study showing that although some variations of sentences with transposed letters are relatively easy to read, other variations are not, and that there is generally always a cost associated with reading words with transposed letters. We asked 30 college students at the University of Durham, United Kingdom, to read 80 sentences in which letters were transposed. In each sentence, transpositions were consistently located at the beginnings, middles, or ends of words (see Table 1). About 40% of the words in the sentences (all content words longer than four letters) had letter transpositions. In addition, the students read sentences without any transpositions. Eye movements were recorded via a Fourward Technology Dual Purkinje eyetracker; the spatial resolution of this eyetracker is less than 10 min of arc. Comprehension questions were asked after 30% of the sentences. Readers were able to answer the questions with high accuracy, but 50% of them indicated that there were a few words that they did not understand. Whereas the base reading rate for normal sentences was 255 words per minute (wpm), all of the variations involving letter transpositions resulted in some cost to reading. When internal letters were transposed, the reading rate was 227 wpm (an 11% decrement in reading speed). However, when the transpositions involved the ending letters of words, reading rate was 189 wpm (a 26% decrement), and when the transpositions were at the beginnings of the words, reading rate was 163 wpm (a 36% decrement). Readers made more and longer eye fixations (see Table 1) with the more difficult transpositions. The Internet statement was correct in that some letter transpositions do yield words that are relatively easy to read. However, our results clearly demonstrate that transpositions always carry a cost. Furthermore, our research also shows that transpositions vary in their costliness depending on their location in the word: Transpositions of internal letters are much less costly than transpositions of ending letters, which in turn are less costly than transpositions of beginning letters. These results demonstrate the importance of beginning letters for word recognition (see Rayner & Pollatsek, 1989, for a summary). In other work (Christianson, Johnson, & Rayner, 2005), we have also demonstrated that letter transpositions that cross morpheme boundaries (even with internal letters) are associated with an additional cost. Thus, susnhine is more difficult to read than sunhsine. Finally, a previous study showed that when letters are substituted rather than transposed, readers take much longer to read sentences (Rayner & Kaiser, 1975). In the case of substitutions involving visually similar letters, substitutions for internal letters (e.g., problem printed as pncblem) doubled reading time, as did substitutions for ending letters (e.g., problnc); substitutions for beginning letters (e.g., qroblem) were associated with reading times 2.5 times longer than normal. In the case of substitutions involving visually dissimilar letters, substitutions for internal letters (e.g., prkylem) or final letters (e.g., problky) tripled reading time; substitutions for beginning letters (e.g., fyoblem) quadrupled reading time. In all cases (except when visually similar letters were substituted for internal letters), substitutions also reduced comprehension.

Reading Disappearing Text Cognitive Control of Eye Movements

Participants read sentences containing high- or low-frequency target words under normal reading conditions or disappearing-text conditions (in which the word that was fixated disappeared after 60 ms). Even though the fixated word had disappeared after 60 ms, there was still a robust frequency effect wherein readers fixated longer on low-frequency words than on high-frequency words. Thus, the results are consistent with cognitive-control models of eye movement control and inconsistent with visual/oculomotor-control models. Although the uptake of visual information is clearly important for reading, it is the cognitive processes associated with understanding the fixated words that drive the eyes through the text.

On the processing of meaning from parafoveal vision during eye fixations in reading

Full details of this book are available on the Elsevier Publishing website, see http://www.elsevier.com/wps/find/bookdescription.cws_home/667174/description#description

Binocular coordination of eye movements during reading.

Binocular coordination of the eyes during reading was examined. Fixation disparity greater than one character occurred on 47% of fixations, with the disparity being predominantly uncrossed (39%), though a small proportion of fixations were crossed. The average magnitude of disparity, measured at the end of fixation, was 1.1 characters for all fixations. For the 47% of non-aligned fixations the average magnitude of disparity was 1.9 characters. Vergence movements that reduced fixation disparity occurred during fixations, and their magnitude was positively correlated with fixation duration. Finally, eye dominance did not modulate fixation disparity magnitude or the proportion of disparate fixations.

Eye movements and the modulation of parafoveal processing by foveal processing difficulty: A reexamination

Henderson and Ferreira (1990) found that foveal load (manipulated via word frequency) modulates parafoveal processing, thereby affecting the amount of preview benefit obtained from the word to the right of fixation. The present experiment used the eye-contingent boundary paradigm and, consistent with Henderson and Ferreira, showed that foveal load modulated preview benefit for participants who were not aware of the display changes during reading. Also, for these participants, foveal load modulated preview benefit regardless of fixation durations on the foveal word. For participants who were aware of the display change, preview benefits occurred regardless of foveal processing difficulty. These results have important implications for understanding the way in which foveal load influences parafoveal processing during reading.

The binocular coordination of eye movements during reading in children and adults

Recent evidence indicates that each eye does not always fixate the same letter during reading and there has been some suggestion that processing difficulty may influence binocular coordination. We recorded binocular eye movements from children and adults reading sentences containing a word frequency manipulation. We found disparities of significant magnitude between the two eyes for all participants, with greater disparity magnitudes in children than adults. All participants made fewer crossed than uncrossed fixations. However, children made a higher proportion of crossed fixations than adults. We found no influence of word frequency on childrens fixations and on binocular coordination in adults.

Binocular coordination of the eyes during reading: Word frequency and case alternation affect fixation duration but not fixation disparity

This experiment investigated whether properties of the text being read affect binocular coordination of the eyes during reading. Readers’ binocular eye movements were recorded while they read sentences that contained high- and low-frequency words. In addition, half of the sentences were presented in normal case, and half were presented in alternating case (i.e., AlTeRnAtInG cAsE). Past research has suggested that the visual system tolerates less binocular fixation disparity with alternating than with normal case (Heller & Radach, 1999). While both word frequency and alternating case produced large effects on fixation durations on the target word, neither manipulation affected the magnitude of fixation disparity. It is concluded that linguistic and visual properties of the text being read do not influence binocular coordination of the eyes during reading. Additional analyses also showed no difference in fixation disparity between reading and a nonlinguistic task. Implications of these results for split-fovea models of reading are discussed.

Word length and landing position effects during reading in children and adults

The present study examined the effects of word length on childrens eye movement behaviour when other variables were carefully controlled. Importantly, the results showed that word length influenced childrens reading times and fixation positions on words. Furthermore, children exhibited stronger word length effects than adults in gaze durations and refixations. Adults and children generally did not differ in initial landing positions, but did differ in refixation behaviour. Overall, the results indicated that while adults and children show similar effects of word length for early measures of eye movement behaviour, differences emerge in later measures.

Orthographic familiarity influences initial eye fixation positions in reading

An important issue in the understanding of eye movements in reading is what kind of nonfoveal information can influence where we move our eyes. In Experiment 1, first fixation landing positions were nearer the beginning of misspelled words. Experiment 2 showed that the informativeness of word beginnings does not influence where words are first fixated. In both experiments, refixations were more likely to be to the left of the initial fixation position if the words were misspelled. Also, there was no influence of spelling on prior fixation durations or refixation probabilities, that is, there was no evidence for parafoveal‐on‐foveal effects. The results show that the orthographic familiarity, but not informativeness, of word initial letter sequences influences where words are first fixated.