title: Micro and regular saccades across the lifespan during a visual search of "Where's Waldo" puzzles.
abstract: Despite the fact that different aspects of visual-motor control mature at different rates and aging is associated with declines in both sensory and motor function, little is known about the relationship between microsaccades and either development or aging. Using a sample of 343 individuals ranging in age from 4 to 66 and a task that has been shown to elicit a high frequency of microsaccades (solving Where's Waldo puzzles), we explored microsaccade frequency and kinematics (main sequence curves) as a function of age. Taking advantage of the large size of our dataset (183,893 saccades), we also address (a) the saccade amplitude limit at which video eye trackers are able to accurately measure microsaccades and (b) the degree and consistency of saccade kinematics at varying amplitudes and directions. Using a modification of the Engbert-Mergenthaler saccade detector, we found that even the smallest amplitude movements (0.25-0.5°) demonstrate basic saccade kinematics. With regard to development and aging, both microsaccade and regular saccade frequency exhibited a very small increase across the life span. Visual search ability, as per many other aspects of visual performance, exhibited a U-shaped function over the lifespan. Finally, both large horizontal and moderate vertical directional biases were detected for all saccade sizes.
authors.affiliation: School of Optometry, Indiana University, 800 E Atwater Ave, Bloomington, IN 47405, United States; Program in Neuroscience, Department of Psychological and Brain Sciences, Cognitive Science Program, Indiana University, United States. Electronic address: nport@indiana.edu.
authors.forename: Nicholas L
authors.initials: NL
authors.lastname: Port
authors.affiliation: School of Optometry, Indiana University, 800 E Atwater Ave, Bloomington, IN 47405, United States; Illinois College of Optometry, 3241 South Michigan Avenue, Chicago, IL 60616, United States.
authors.forename: Jane
authors.initials: J
authors.lastname: Trimberger
authors.affiliation: School of Optometry, Indiana University, 800 E Atwater Ave, Bloomington, IN 47405, United States.
authors.forename: Steve
authors.initials: S
authors.lastname: Hitzeman
authors.affiliation: School of Optometry, Indiana University, 800 E Atwater Ave, Bloomington, IN 47405, United States.
authors.forename: Bryan
authors.initials: B
authors.lastname: Redick
authors.affiliation: Illinois College of Optometry, 3241 South Michigan Avenue, Chicago, IL 60616, United States.
authors.forename: Stephen
authors.initials: S
authors.lastname: Beckerman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001288:Attention / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005403:Fixation, Ocular; D006801:Humans; D008297:Male; D008875:Middle Aged; D010775:Photic Stimulation; D012438:Saccades / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Microsaccades; Saccade kinematics; Visual search