Latency of sequential eye movements: implications for reading

The best available estimates indicate that the average minimum latency of saccadic eye movements (175-200 msec) approaches the mean duration of fixations in reading (200-250 msec). This fact presents a problem for models of reading which assume that an eye movement is initiated only after substantial information is processed on a fixation. Three experiments are reported that support earlier estimates of saccadic latency; the experiments were conducted under conditions in which the length of measured latencies could not reflect a motoric refractory period, spatial uncertainty, or temporal uncertainty.     

The acquisition of parafoveal word information in reading

A somewhat counterintuitive finding has emerged from experiments that restrict the "window" of visual information available on a fixation during reading: fixation duration increases even though there is less information to process on a fixation. The two most likely explanations for this phenomenon are: (1) that the reader extracts abnormal information outside the window and this slows down processing; (2) that a restricted window does not allow a preview of a word before it is fixated, and hence identification of the word is slower when the word subsequently is fixated. In the present experiments, these two alternatives were tested. Conditions in which the size of the window alternated between fixations were compared with conditions in which the size of the window remained constant from fixation to fixation. This manipulation allowed us to separate effects due to restriction of the size of the window on the current fixation from preview benefits (which would be due to restriction of the size of the window on the prior fixation). Two experiments demonstrated clear beneficial effects on fixation duration due to receiving a preview of a word on the fixation prior to when it was fixated. In contrast, restriction of the size of the window had only marginal effects on the fixation on which that restriction occurred. In addition, a subsidiary analysis suggested that the benefit of previewing a word was influenced by its length; for short words, a preview primarily allowed the reader to skip the word more frequently, whereas for longer words, a preview primarily shortened the fixation time on the word when it was later fixated.     

Asymmetry of the effective visual field in reading

In three experiments, subjects’ eye movements were recorded as they read from a computer-controlled CRT. The amount of information available to the left and right of the fixation point was varied in order to determine the characteristics of the effective visual field in reading. Experiments 1 and 2 demonstrated that readers do not obtain useful information during a fixation more than 3 or 4 letters to the left of their fixation point. The results of Experiment 3 indicated that the effective visual field does not extend any further to the left than the beginning of the word currently fixated, independent of the number of letters available to the left of fixation. When combined with the results of other research on the perceptual span in reading, the results of these experiments indicate that the effective visual field extends from the beginning of the currently fixated word (but no further than 4 characters to the left of fixation) up to about 15 characters to the right of fixation.     

A study of evaluative problem solving Part I. observations on adults

Six young adults were observed playing each other at a league type series of the board game pegity. This gave an opportunity to observe the development of strategies in the play. Some systematic errors in the play were also investigated.     

Space Cannot Be Cut—Why Self-Identity Naturally Includes Neighbourhood

Psychology is not alone in its struggle with conceptualizing the dynamic relationship between space and individual or collective identity. This general epistemological issue haunts biology where it has a specific focus in evolutionary arguments. It arises because of the incompatibility between definitive logical systems of ‘contradiction or unity’, which can only apply to inert material systems, and natural evolutionary processes of cumulative energetic transformation. This incompatibility makes any attempt to apply definitive logic to evolutionary change unrealistic and paradoxical. It is important to recognise, because discrete perceptions of self and group, based on the supposition that any distinguishable identity can be completely cut free, as an ‘independent singleness’, from the space it inescapably includes and is included in, are a profound but unnecessary source of psychological, social and environmental conflict. These perceptions underlie Darwin’s definition of ‘natural selection’ as ‘the preservation of favoured races in the struggle for life’. They result in precedence being given to striving for homogeneous supremacy, through the competitive suppression of others, instead of seeking sustainable, co-creative evolutionary relationship in spatially and temporally heterogeneous communities. Here, I show how ‘natural inclusion’, a new, post-dialectic understanding of evolutionary process, becomes possible through recognising space as a limitless, indivisible, receptive (non-resistive) ‘intangible presence’ vital for movement and communication, not as empty distance between one tangible thing and another. The fluid boundary logic of natural inclusion as the co-creative, fluid dynamic transformation of all through all in receptive spatial context, allows all form to be understood as flow-form, distinctive but dynamically continuous, not singularly discrete. This simple move from regarding space and boundaries as sources of discontinuity and discrete definition to sources of continuity and dynamic distinction correspondingly enables self-identity to be understood as a dynamic inclusion of neighbourhood, through the inclusion of space throughout and beyond all natural figural forms as configurations of energy. Fully to appreciate and communicate the significance of this move, it is necessary to widen the linguistic, mathematical and imaginative remit of conventional scientific argument and explication so as to include more poetic, fluid and artistic forms of expression.     

Future Directions for Eye Movement Research

Eyemovementdatahaveproventobeex鄄tremelyusefulinthestudyofmanytopicsrelatedtocognitiveprocessing.Indeed,theymaybethebeston-linemeasureofmoment-to-momentcogni鄄tiveprocesses.Thisisnottosaythateyemove鄄mentswillproveusefulineveryaspectofcognitiveprocessing.Forexample,itisdifficulttoseehoweyemovementsmayrevealagreatdealaboutbasicmemoryprocesses(but,evenhere,theycouldbeusefulindeterminingexactlywhatpeoplerememberfromasceneorvisualdisplay).Inthisarticle,Iwillbrieflysummarizesomeimportantfindingsth…