The perceptual span and oculomotor activity during the reading of Chinese sentences

The paramyxovirus fusion (F) protein mediates membrane fusion. The biologically active F protein consists of a membrane distal subunit, F2, and a membrane-anchored subunit, F1. We have identified a highly stable structure composed of peptides derived from the F1 heptad repeat A, which abuts the hydrophobic fusion peptide (peptide N-1), and the F1 heptad repeat B, located 270 residues downstream and adjacent to the transmembrane domain (peptides C-1 and C-2). In isolation, peptide N-1 is 47% alpha-helical and peptide C-1 and C-2 are unfolded. When mixed together, peptides N1 + C1 form a thermostable (Tm >90 degreesC), 82% alpha-helical, discrete trimer of heterodimers (mass 31,300 Mr) that is resistant to denaturation by 2% SDS at 40 degreesC. We suggest that this alpha-helical trimeric complex represents the core most stable form of the F protein that either is fusion competent or forms after fusion has occurred. Peptide C-1 is a potent inhibitor of both the lipid mixing and the aqueous content mixing fusion activity of the SV5 F protein. In contrast, peptides N-1 and N-2 inhibit cytoplasmic content mixing but not lipid mixing, leading to a stable hemifusion state. Thus, these peptides define functionally different steps in the fusion process. The parallels among both the fusion processes and the protein structures of paramyxovirus F proteins, HIV gp41, and influenza virus hemagglutinin are discussed, as the analogies are indicative of a conserved paradigm for fusion promotion among fusion proteins from widely disparate viruses.     

Temporal overlap in the linguistic processing of successive words in reading: Reply to Pollatsek, Reichle, and Rayner (2006a).

A. Pollatsek, E. D. Reichle, and K. Rayner (see record 2006-22004-014) argue that the critical findings in A. W. Inhoff, B. M. Eiter, and R. Radach (see record 2005-13471-012) are in general agreement with core assumptions of sequential attention shift models if additional assumptions and facts are considered. The current authors critically discuss the hypothesized time line of processing and indicate that the success of Pollatsek et al.'s simulation is predicated on a gross underestimation of the pretarget word's viewing duration in Inhoff et al. and that the actual data are difficult to reconcile with the strictly serial attention shift assumption. The authors also discuss attention shifting and saccade programming assumptions in the E-Z Reader model and conclude that these are not in harmony with research in related domains of study. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Eye-hand span and coding of text during copytyping.

Examined concurrent oculomotor and manual activities during copytyping to determine whether (1) typists keep the eyes 1-sec ahead of the executed keypress, (2) control of eye–hand (E–H) coordination follows the lexical representation of to-be-typed text, and (3) typists seek visual information beyond the boundaries of the fixated word. To-be-typed text contained high- and low-frequency target words that were either short or long. Two viewing conditions were used revealing either the directly fixated word only or the fixated word plus the next word in the text. The results showed no support for the 1-sec E–H lag hypothesis. The E–H span was also not affected by the visibility of text but was a function of word frequency, suggesting that E–H coordination follows the lexical representation of text. Effects of window size indicated that typists seek visual information beyond the boundaries of the fixated word. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Seeing morphemes: Loss of visibility during the retinal stabilization of compound and pseudocompound words.

When stabilized, retinal image fades from vision. Earlier studies suggested that knowledge constrains the loss of vision, as disappearing images fragment into familiar subpatterns. Effects of image stabilization on word perception were used in the current study to examine effects of morphemic knowledge on stimulus fragmentations. Bimorphemic compound words (in which beginning and ending trigrams formed morphemic subword units) and monomorphemic pseudocompound words (with a similar trigram structure) were stabilized. Stimulus fragmentations generally resulted in the visibility of lexically nondistinct strings of letters. However, internal morpheme boundaries also affected the loss of vision when compound words were stabilized. Two follow-up experiments indicated that morpheme-related loss of vision was neither the result of differential forgetting rates nor of guessing bias. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encoding of text, manual movement planning, and eye-hand coordination during copytyping.

Typing span and coordination of word viewing times with word typing times in copytyping were examined. In Exp 1, typists copied passages of text while their eye movements were measured. Viewing location was determined during each eye fixation and was used to control the amount of usable visual information. Viewing constraints decreased interword saccade size when fewer than 7 character spaces of text were visible to the right of fixation and increased interkeypress times when fewer than 3 character spaces of text were visible. The eye–hand span amounted to 2.8 character spaces. Exp 2 revealed increases in word typing times and word viewing times as biomechanic typing difficulty increased and word frequency decreased. These findings are consistent with a model of eye–hand coordination that postulates that eye–hand coordination involves central and peripheral processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Time Course of Linguistic Information Extraction From Consecutive Words During Eye Fixations in Reading.

Sequential attention shift models of reading predict that an attended (typically fixated) word must be recognized before useful linguistic information can be obtained from the following (parafoveal) word. These models also predict that linguistic information is obtained from a parafoveal word immediately prior to a saccade toward it. To test these assumptions, sentences were constructed with a critical pretarget-target word sequence, and the temporal availability of the (parafoveal) target preview was manipulated while the pretarget word was fixated. Target viewing effects, examined as a function of prior target visibility, revealed that extraction of linguistic target information began 70-140 ms after the onset of pretarget viewing. Critically, acquisition of useful linguistic information from a target was not confined to the ending period of pretarget viewing. These results favor theoretical conceptions in which there is some temporal overlap in the linguistic processing of a fixated and parafoveally visible word during reading. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Attention demands during reading and the occurrence of brief (express) fixations

It is generally accepted that skin regeneration in warm-blooded animals always results in scar formation. Still we have found that the skin regenerated in place of full-thick square skin wounds often resemble the normal one rather than the connective tissue scar by structure. Morphological variability of the skin regenerates proved to depend on the wound location and the animal species. The possibility of formation of the skin derivatives (hair follicles, fat and sweet glands, skin folds) has been shown. A classification of the skin regenerates has been proposed. Numerous examples demonstrate the skin ability to give rise to organ-specific regenerates with the morphological features specific for the wound site.     

Lexical access during eye fixations in reading: Effects of word-initial letter sequence.

Tested the constraint hypothesis, which states that lexical access in reading is initiated on the basis of word-initial letter information obtainable in the parafoveal region, in 2 experiments. Ss were 36 college students with normal vision. Eye movements were monitored while Ss read sentences containing target words whose initial trigram (Exp I) or bigram (Exp II) imposed either a high or a low degree of constraint in the lexicon. In contradiction to the hypothesis, high-constraint words (e.g., dwarf) received longer fixations than did low-constraint words (e.g., clown), despite the fact that high-constraint words have an initial letter sequence shared by few other words in the lexicon. A comparison of fixation times in viewing conditions with and without parafoveal letter information showed that the amount of decrease in target fixation time due to prior parafoveal availability was the same for high- and low-constraint targets. It is concluded that increased familiarity of word-initial letter sequence is beneficial to lexical access and that familiarity affects the efficiency of foveal but not parafoveal processing. A list of the sentences used in the 2 experiments is appended. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word integration and regression programming during reading: A test of the E-Z reader 10 model.

Participants read sentences with two types of target nouns, one that did and one that did not require a determiner to form a legal verb–noun phrase sequence. Sentences were presented with and without the critical determiner to create a local noun integration difficulty when a required determiner was missing. The absence of a required determiner did not influence 1st-pass reading of the verb, the noun, and the posttarget word. It did, however, have a profound effect on 2nd-pass reading. All three words were a likely target of a regression when a required determiner was missing, and the noun and the posttarget word were likely sources of a regression. These results are consistent with novel E-Z reader model assumptions, according to which identification of the noun should be followed by its integration, and integration difficulties can lead to the initiation of a regression to the noun. However, integration difficulties influenced eye movements earlier and later than predicted by the new model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exterior letters are not privileged in the early stage of visual word recognition during reading: Comment on Jordan, Thomas, Patching and Scott-Brown (2003).

Potential sources for the discrepancy between the letter position effects in T. R. Jordan, S. M. Thomas, G. R. Patching, and K. C. Scott-Brown's (2003; see record 2003-07955-013) and D. Briihl and A. W. Inhoff s (1995; see record 1995-20036-001) studies are examined. The authors conclude that the lack of control over where useful information is acquired during reading in Jordan et al.'s study, rather than differences in the orthographic consistency and the availability of word shape information, account for the discrepant effect pattern in the 2 studies. The processing of a word during reading begins before it is fixated, when beginning letters occupy a particularly favorable parafoveal location that is independent of word length. Knowledge of parafoveal word length cannot be used to selectively process exterior letters during the initial phase of visual word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)