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SUMMARY:Uncomfortable images and spatial periodicity in nature\, in art\, 
 and in text - Arnold Wilkins\, University of Essex
DTSTART:20070703T120000Z
DTEND:20070703T130000Z
UID:TALK7574@talks.cam.ac.uk
CONTACT:Cordula Becker
DESCRIPTION:We find that ratings of discomfort from a wide variety of\nima
 ges can be predicted from the energy at different spatial scales  \nin the
  image\, as measured by the Fourier amplitude spectrum of the  \nluminance
 . Whereas comfortable images show the regression of  \nFourier amplitude a
 gainst spatial frequency common in natural  \nscenes\, uncomfortable image
 s show a regression with  \ndisproportionately greater amplitude at spatia
 l frequencies within  \ntwo octaves of 3 cycles per degree. In six studies
 \, the amplitude  \nat this spatial frequency\, relative to that 3 octaves
  below\,  \nexplains variance in judgments of discomfort from art\, from i
 mages  \nconstructed from filtered noise and from art in which the phase o
 r  \namplitude spectra have been altered.\n\nIn a further eight studies of
  word reading we find that the first\npeak in the horizontal autocorrelati
 on of the image of a word predicts\nthe  \nspeed with which the word can b
 e read\, both aloud and silently.  \nSubtlety distorting the horizontal di
 mension of words so as to  \nreduce the spatial periodicity increases read
 ing speed in poor  \nreaders.\n\nStriped patterns are known to be uncomfor
 table and capable of\nprovoking headaches and seizures in susceptible pers
 ons. The  \npresent findings show for the first time that spatial periodic
 ity  \nmay be associated with aversion and with visual inefficiency in  \n
 images more complex than simple geometric patterns - images such as art\na
 nd text.\n\nWe propose a simple measurement that can predict a negative pu
 blic  \nreaction to art. We propose simple changes to the design of text t
 hat\ncan  \nreduce the spatial periodicity
LOCATION:Seminar Room (ground floor)\, Craik-Marshall Building
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