Peripheral vision and pattern recognition: a review - strasburger - main

Peripheral_Vision.doc
Concerning the physiological substrate underlying the psychophysical measurements,
Wertheim (1894) and Fick (1898) related them to the density of retinal receptor cells. Excellent
data on retinal cone and rod receptor densities were provided by Østerberg (1935) (Figure 4;
note the detail with which these measurements were taken) and still underlie many current
textbook figures. Polyak (1932) went one step further and concluded from his anatomical
studies that there must be a mathematical function which describes the retino-cortical mapping.
Talbot and Marshall (1941) studied this in the central part of the visual field and derived a
projection factor that could be expressed by a single number. Yet acuity data and receptor
densities remained in the center of interest (e.g. Pirenne, 1962). Weymouth (1958) concluded
that receptor densities cannot underlie many of the decline functions from his extensive
overview of acuity and other spatial visual performance measures (Figure 5), as well as of the
neurophysiological literature. Instead he proposed retinal ganglion cells as the possible
neurophysiological substrate (cf. Curcio & Allen, 1990).
Figure 4. Cone and rod receptor density results by
Østerberg (1935). These data underlie many of the
current textbook figures.
Figure 5. MAR functions reviewed by
Weymouth (1958). “Comparison of vernier
threshold, minimal angle of resolution,
motion threshold, and mean variation of the
settings of horopter rods” (1958, Fig. 13)
For decades acuities had been plotted on the ordinate of a typical graph – i.e., the inverse of a
spatial threshold – but Weymouth advocated going back to showing the spatial thresholds
directly. He called the latter “minimum angle of resolution” (MAR), a term still used today.
Daniel and Whitteridge (1961) and Cowey and Rolls (1974) were next to study the relationship
between the retinal and the primary cortical mapping, a strand of research that had started with
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