The distribution of fixation durations in infants and naive adults

The distributions of durations of fixations from infants and free-viewing adults are shown to be basically exponential for different stimulus conditions. It is found that fixation duration can be divided into two periods. One, the alpha-period, is a refractory period during which a saccade does not occur and fluctuates across fixations. The other, the beta-period, is a random variable intrinsic to each fixation and constitutes a waiting-time for a saccade that occurs with constant probability per unit time. It is shown that mean duration decreases when stimulus size increases. These results suggest that fixations are terminated by saccades triggered by non-foveal stimulation.

[1]  J. D. Gould,et al.  Eye movements during visual search and memory search. , 1973, Journal of experimental psychology.

[2]  George W. McConkie,et al.  Estimating frequency and size of effects due to experimental manipulations in eye movement research , 1985 .

[3]  J. Pettigrew,et al.  Conjugate and disjunctive saccades in two avian species with contrasting oculomotor strategies , 1985, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[4]  Patrick Suppes,et al.  A procedural theory of eye movements in doing arithmetic , 1983 .

[5]  J D Gould,et al.  Studies of Visual Inspection. , 1973, Ergonomics.

[6]  G. Bronson,et al.  The Scanning Patterns of Human Infants: Implications for Visual Learning , 1982 .

[7]  L. Hainline,et al.  Infants' scanning of geometric forms varying in size. , 1982, Journal of experimental child psychology.

[8]  N R BARTLETT,et al.  Latency and duration of eye movements in the horizontal plane. , 1962, Journal of the Optical Society of America.

[9]  A S Cohen.  Is the Duration of an Eye Fixation a Sufficient Criterion Referring to Information Input? , 1977, Perceptual and motor skills.

[10]  Christopher M. Harris,et al.  Characteristics of saccades in human infants , 1984, Vision Research.

[11]  B. Fischer,et al.  Saccadic eye movements after extremely short reaction times in the monkey , 1983, Brain Research.

[12]  J. Gibson.  The perception of the visual world , 1951 .

[13]  L L Wheeless,et al.  Eye-movement responses to step and pulse-step stimuli. , 1966, Journal of the Optical Society of America.

[14]  Kishor S. Trivedi.  Probability and Statistics with Reliability, Queuing, and Computer Science Applications , 1984 .

[15]  William Feller,et al.  An Introduction to Probability Theory and Its Applications , 1951 .

[16]  D. Cox,et al.  Analysis of Survival Data. , 1985 .

[17]  S R Ellis,et al.  Statistical Dependency in Visual Scanning , 1986, Human factors.

[18]  Chris Harris,et al.  Instrument considerations in measuring fast eye movements , 1984 .

[19]  William Feller,et al.  An Introduction to Probability Theory and Its Applications , 1967 .

[20]  M. Sigman,et al.  INFANT SACCADIC EYE MOVEMENTS DURING HABITUATION TO A GEOMETRIC PATTERN , 1987 .

[21]  J M ENOCH,et al.  Effect of the size of a complex display upon visual search. , 1959, Journal of the Optical Society of America.

[22]  Louise Hainline,et al.  An automated eye movement recording system for use with human infants , 1981 .

[23]  Nancy Millette,et al.  How People Look at Pictures , 1935 .