Abstract

Humans use saccadic eye movements when they search for visual targets. We investigated the relationship between the visual processing used by saccades and perception during search by comparing saccadic and perceptual decisions under conditions in which each had access to equal visual information. We measured the accuracy of perceptual judgments and of the first search saccade over a wide range of target saliences [signal-to-noise ratios (SNRs)] in both a contrast-detection and a contrast-discrimination task. We found that saccadic and perceptual performances (1) were similar across SNRs, (2) showed similar task-dependent differences, and (3) were well described by a model based on signal detection theory that explicitly includes observer uncertainty [M. P. Eckstein et al., J. Opt. Soc. Am. A 14, 2406 (1997)]. Our results demonstrate that the accuracy of the first saccade provides much information about the observer’s perceptual state at the time of the saccadic decision and provide evidence that saccades and perception use similar visual processing mechanisms for contrast detection and discrimination.

© 2003 Optical Society of America

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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
  49. M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity by target uncertainty,” Nature (London) 389, 66–69 (1997).
    [CrossRef]
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    [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
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    [CrossRef]
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  61. This definition compares human- and ideal-observer performances at the same SNR. As suggested by a reviewer, it is also possible to define efficiency as a comparison between the human- and ideal-observer SNRs required to achieve the same performance level. In this alternative definition, efficiency is equal to (SNRideal/SNRhuman)2.The two definitions are equivalent if human d′is directly proportional to SNR (uncertainty is equal to zero), as is the case for our discrimination task. They are not the same for nonzero uncertainty (nonzero intercept), as is the case for our detection task.

2003 (1)

2002 (1)

R. M. McPeek, E. L. Keller, “Superior colliculus activity related to concurrent processing of saccade goals in a visual search task,” J. Neurophysiol. 87, 1805–1815 (2002).
[PubMed]

2001 (3)

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Quantifying the performance limits of human saccadic targeting during visual search,” Perception 30, 1389–1401 (2001).
[CrossRef]

J. M. Findlay, V. A. Brown, I. D. Gilchrist, “Saccade target selection in visual search: the influence of information from the previous fixation,” Vision Res. 41, 87–95 (2001).
[CrossRef] [PubMed]

P. W. Glimcher, “Making choices: the neurophysiology of visual-saccadic decision making,” Trends Neurosci. 24, 654–659 (2001).
[CrossRef] [PubMed]

2000 (4)

B. R. Beutter, M. P. Eckstein, L. S. Stone, “Parallel differences in contrast-discrimination and detection performance for saccades and perception in visual search,” Invest. Ophthalmol. Visual Sci. (Suppl.) 41, S424 (2000).

R. M. McPeek, A. A. Skavenski, K. Nakayama, “Concurrent processing of saccades in visual search,” Vision Res. 40, 2499–2516 (2000).
[CrossRef] [PubMed]

J. Palmer, P. Verghese, M. Pavel, “The psychophysics of visual search,” Vision Res. 40, 1227–1268 (2000).
[CrossRef] [PubMed]

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Task information increases from the first to the second saccade in visual search of a target among distractors,” Invest. Ophthalmol. Visual Sci. 41, 759 (2000).

1999 (8)

L. S. Stone, B. R. Beutter, M. P. Eckstein, “Salience effects on perceptual and saccadic target localization during search,” Soc. Neurosci. Abstr. 25, 548 (1999).

Z. L. Lu, B. A. Dosher, “Characterizing human perceptual inefficiencies with equivalent internal noise,” J. Opt. Soc. Am. A 16, 764–778 (1999).
[CrossRef]

T. Hooge, C. J. Erkelens, “Peripheral vision and oculomotor control during visual search,” Vision Res. 39, 1567–1575 (1999).
[CrossRef] [PubMed]

C. L. Colby, M. E. Goldberg, “Space and attention in parietal cortex,” Annu. Rev. Neurosci. 23, 319–349 (1999).
[CrossRef]

R. J. Krauzlis, A. Z. Zivotofsky, F. A. Miles, “Target selection for pursuit and saccadic eye movements in humans,” J. Cogn. Neurosci. 11, 641–649 (1999).
[CrossRef] [PubMed]

R. M. McPeek, V. Maljkovic, K. Nakayama, “Saccades require focal attention and are facilitated by a short-term memory system,” Vision Res. 39, 1555–1566 (1999).
[CrossRef] [PubMed]

D. Gilchrist, C. A. Heywood, J. M. Findlay, “Saccade selection in visual search: evidence for spatial frequency specific between-item interactions,” Vision Res. 39, 1373–1383 (1999).
[CrossRef] [PubMed]

J. D. Schall, K. G. Thompson, “Neural selection and control of visually guided eye movements,” Annu. Rev. Neurosci. 22, 241–259 (1999).
[CrossRef] [PubMed]

1998 (6)

J. P. Gottlieb, M. Kusunoki, M. E. Goldberg, “The representation of visual salience in monkey parietal cortex,” Nature (London) 391, 481–484 (1998).
[CrossRef]

M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity in superior colliculus by changes in target probability,” J. Neurosci. 18, 7519–7534 (1998).
[PubMed]

M. P. Eckstein, “The lower efficiency for conjunctions is due to noise and not serial visual attention,” Psychol. Sci. 9, 111–118 (1998).
[CrossRef]

C. Motter, E. J. Belky, “The guidance of eye movements during active visual search,” Vision Res. 38, 1805–1815 (1998).
[CrossRef] [PubMed]

T. Hooge, C. J. Erkelens, “Adjustment of fixation duration in visual search,” Vision Res. 38, 1295–1302 (1998).
[CrossRef] [PubMed]

B. R. Beutter, L. S. Stone, “Human motion perception and smooth eye movements show similar directional biases for elongated apertures,” Vision Res. 38, 1273–1286 (1998).
[CrossRef] [PubMed]

1997 (4)

M. P. Eckstein, A. J. Ahumada, A. B. Watson, “Visual signal detection in structured backgrounds. II. Effect of contrast gain control, background variations and white noise,” J. Opt. Soc. Am. A 14, 2406–2419 (1997).
[CrossRef]

W. S. Geisler, D. G. Albrecht, “Visual cortex neurons in monkeys and cats: detection, discrimination and identification,” Visual Neurosci. 14, 897–919 (1997).
[CrossRef]

J. M. Findlay, “Saccade target selection during visual search,” Vision Res. 37, 617–631 (1997).
[CrossRef] [PubMed]

M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity by target uncertainty,” Nature (London) 389, 66–69 (1997).
[CrossRef]

1996 (3)

1995 (3)

W. S. Geisler, L. Chou, “Separation of low-level and high-level factors in complex tasks: visual search,” Psychol. Rev. 102, 356–378 (1995).
[CrossRef] [PubMed]

W. S. Geisler, D. G. Albrecht, “Bayesian analysis of identification performance in monkey visual cortex: nonlinear mechanisms and stimulus certainty,” Vision Res. 35, 2723–2730 (1995).
[CrossRef] [PubMed]

J. D. Schall, “Neural basis of saccade target selection,” Rev. Neurosci. 6, 63–85 (1995).
[CrossRef] [PubMed]

1994 (2)

R. F. Hess, A. Hayes, “The coding of spatial position by the human visual system: effects of spatial scale and retinal eccentricity,” Vision Res. 34, 625–643 (1994).
[CrossRef] [PubMed]

J. Palmer, “Set-size effects in visual search: the effect of attention is independent of the stimulus for simple tasks,” Vision Res. 34, 1703–1721 (1994).
[CrossRef] [PubMed]

1993 (1)

L. Chelazzi, E. K. Miller, J. Duncan, R. Desimone, “A neural basis for visual search in inferior temporal cortex,” Nature (London) 363, 345–347 (1993).
[CrossRef]

1989 (1)

P. He, E. Kowler, “The role of location probability in the programming of saccades: implications for center-of-gravity tendencies,” Vision Res. 29, 1165–1181 (1989).
[CrossRef]

1988 (1)

1987 (1)

1985 (1)

1983 (1)

D. J. Tolhurst, J. A. Movshon, F. A. Dean, “The statistical reliability of signals in single neurons in cat and monkey visual cortex,” Vision Res. 23, 775–785 (1983).
[CrossRef] [PubMed]

1982 (1)

P. Viviani, R. G. Swensson, “Saccadic eye movements to peripherally discriminated visual targets,” J. Exp. Psychol. Hum. Percept. Perform. 16, 459–478 (1982).

1981 (1)

A. E. Burgess, R. F. Wagner, R. J. Jennings, H. B. Barlow, “Efficiency of human visual signal discrimination,” Science 214, 93–94 (1981).
[CrossRef] [PubMed]

1980 (2)

G. E. Legge, J. M. Foley, “Contrast masking in human vision,” J. Opt. Soc. Am. 70, 1458–1471 (1980).
[CrossRef] [PubMed]

H. B. Barlow, “The absolute efficiency of perceptual decisions,” Proc. R. Soc. London 290, 71–91 (1980).

1979 (1)

W. Becker, R. Jürgens, “An analysis of the saccadic system by means of double step stimuli,” Vision Res. 19, 967–983 (1979).
[CrossRef] [PubMed]

1967 (2)

L. W. Nolte, D. Jaarsma, “More on the detection of one of M orthogonal signals,” J. Acoust. Soc. Am. 41, 497–505 (1967).
[CrossRef]

L. G. Williams, “Target conspicuity and visual search,” Hum. Factors 8, 80–92 (1967).

1966 (1)

L. G. Williams, “The effects of target specification on objects fixated during visual search,” Acta Psychol. 27, 355–360 (1966).
[CrossRef]

1954 (1)

W. W. Peterson, T. G. Birdsall, W. C. Fox, “The theory of signal detectability,” IRE Trans. Inf. Theory PGIT-4, 171–212 (1954).
[CrossRef]

Ahumada, A. J.

Albrecht, D. G.

W. S. Geisler, D. G. Albrecht, “Visual cortex neurons in monkeys and cats: detection, discrimination and identification,” Visual Neurosci. 14, 897–919 (1997).
[CrossRef]

W. S. Geisler, D. G. Albrecht, “Bayesian analysis of identification performance in monkey visual cortex: nonlinear mechanisms and stimulus certainty,” Vision Res. 35, 2723–2730 (1995).
[CrossRef] [PubMed]

Barlow, H. B.

A. E. Burgess, R. F. Wagner, R. J. Jennings, H. B. Barlow, “Efficiency of human visual signal discrimination,” Science 214, 93–94 (1981).
[CrossRef] [PubMed]

H. B. Barlow, “The absolute efficiency of perceptual decisions,” Proc. R. Soc. London 290, 71–91 (1980).

Basso, M. A.

M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity in superior colliculus by changes in target probability,” J. Neurosci. 18, 7519–7534 (1998).
[PubMed]

M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity by target uncertainty,” Nature (London) 389, 66–69 (1997).
[CrossRef]

Becker, W.

W. Becker, R. Jürgens, “An analysis of the saccadic system by means of double step stimuli,” Vision Res. 19, 967–983 (1979).
[CrossRef] [PubMed]

Belky, E. J.

C. Motter, E. J. Belky, “The guidance of eye movements during active visual search,” Vision Res. 38, 1805–1815 (1998).
[CrossRef] [PubMed]

Beutter, B. R.

R. F. Murray, B. R. Beutter, M. P. Eckstein, L. S. Stone, “Saccadic and perceptual performance in visual search tasks. II. Letter discrimination” J. Opt. Soc. Am. A 20, 1356–1370 (2003).
[CrossRef]

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Quantifying the performance limits of human saccadic targeting during visual search,” Perception 30, 1389–1401 (2001).
[CrossRef]

B. R. Beutter, M. P. Eckstein, L. S. Stone, “Parallel differences in contrast-discrimination and detection performance for saccades and perception in visual search,” Invest. Ophthalmol. Visual Sci. (Suppl.) 41, S424 (2000).

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Task information increases from the first to the second saccade in visual search of a target among distractors,” Invest. Ophthalmol. Visual Sci. 41, 759 (2000).

L. S. Stone, B. R. Beutter, M. P. Eckstein, “Salience effects on perceptual and saccadic target localization during search,” Soc. Neurosci. Abstr. 25, 548 (1999).

B. R. Beutter, L. S. Stone, “Human motion perception and smooth eye movements show similar directional biases for elongated apertures,” Vision Res. 38, 1273–1286 (1998).
[CrossRef] [PubMed]

B. R. Beutter, L. S. Stone, M. P. Eckstein, “Correlated saccadic and perceptual decisions in a visual-search detection task reveal spatial-filter overlap,” presented at the Vision Sciences Society Meeting, May 4–8, 2001, Sarasota, Fla., J. Vision1, No. 1 (Abstract 263) (2001), http://www.journalofvision.org/1/3/263/ .

Birdsall, T. G.

W. W. Peterson, T. G. Birdsall, W. C. Fox, “The theory of signal detectability,” IRE Trans. Inf. Theory PGIT-4, 171–212 (1954).
[CrossRef]

Brown, V. A.

J. M. Findlay, V. A. Brown, I. D. Gilchrist, “Saccade target selection in visual search: the influence of information from the previous fixation,” Vision Res. 41, 87–95 (2001).
[CrossRef] [PubMed]

Burgess, A. E.

Chelazzi, L.

L. Chelazzi, E. K. Miller, J. Duncan, R. Desimone, “A neural basis for visual search in inferior temporal cortex,” Nature (London) 363, 345–347 (1993).
[CrossRef]

Chou, L.

W. S. Geisler, L. Chou, “Separation of low-level and high-level factors in complex tasks: visual search,” Psychol. Rev. 102, 356–378 (1995).
[CrossRef] [PubMed]

Colborne, B.

Colby, C. L.

C. L. Colby, M. E. Goldberg, “Space and attention in parietal cortex,” Annu. Rev. Neurosci. 23, 319–349 (1999).
[CrossRef]

Dean, F. A.

D. J. Tolhurst, J. A. Movshon, F. A. Dean, “The statistical reliability of signals in single neurons in cat and monkey visual cortex,” Vision Res. 23, 775–785 (1983).
[CrossRef] [PubMed]

Desimone, R.

L. Chelazzi, E. K. Miller, J. Duncan, R. Desimone, “A neural basis for visual search in inferior temporal cortex,” Nature (London) 363, 345–347 (1993).
[CrossRef]

Dosher, B. A.

Duncan, J.

L. Chelazzi, E. K. Miller, J. Duncan, R. Desimone, “A neural basis for visual search in inferior temporal cortex,” Nature (London) 363, 345–347 (1993).
[CrossRef]

Eckstein, M. P.

R. F. Murray, B. R. Beutter, M. P. Eckstein, L. S. Stone, “Saccadic and perceptual performance in visual search tasks. II. Letter discrimination” J. Opt. Soc. Am. A 20, 1356–1370 (2003).
[CrossRef]

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Quantifying the performance limits of human saccadic targeting during visual search,” Perception 30, 1389–1401 (2001).
[CrossRef]

B. R. Beutter, M. P. Eckstein, L. S. Stone, “Parallel differences in contrast-discrimination and detection performance for saccades and perception in visual search,” Invest. Ophthalmol. Visual Sci. (Suppl.) 41, S424 (2000).

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Task information increases from the first to the second saccade in visual search of a target among distractors,” Invest. Ophthalmol. Visual Sci. 41, 759 (2000).

L. S. Stone, B. R. Beutter, M. P. Eckstein, “Salience effects on perceptual and saccadic target localization during search,” Soc. Neurosci. Abstr. 25, 548 (1999).

M. P. Eckstein, “The lower efficiency for conjunctions is due to noise and not serial visual attention,” Psychol. Sci. 9, 111–118 (1998).
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B. R. Beutter, L. S. Stone, M. P. Eckstein, “Correlated saccadic and perceptual decisions in a visual-search detection task reveal spatial-filter overlap,” presented at the Vision Sciences Society Meeting, May 4–8, 2001, Sarasota, Fla., J. Vision1, No. 1 (Abstract 263) (2001), http://www.journalofvision.org/1/3/263/ .

Erkelens, C. J.

T. Hooge, C. J. Erkelens, “Peripheral vision and oculomotor control during visual search,” Vision Res. 39, 1567–1575 (1999).
[CrossRef] [PubMed]

T. Hooge, C. J. Erkelens, “Adjustment of fixation duration in visual search,” Vision Res. 38, 1295–1302 (1998).
[CrossRef] [PubMed]

Findlay, J. M.

J. M. Findlay, V. A. Brown, I. D. Gilchrist, “Saccade target selection in visual search: the influence of information from the previous fixation,” Vision Res. 41, 87–95 (2001).
[CrossRef] [PubMed]

D. Gilchrist, C. A. Heywood, J. M. Findlay, “Saccade selection in visual search: evidence for spatial frequency specific between-item interactions,” Vision Res. 39, 1373–1383 (1999).
[CrossRef] [PubMed]

J. M. Findlay, “Saccade target selection during visual search,” Vision Res. 37, 617–631 (1997).
[CrossRef] [PubMed]

Foley, J. M.

Fox, W. C.

W. W. Peterson, T. G. Birdsall, W. C. Fox, “The theory of signal detectability,” IRE Trans. Inf. Theory PGIT-4, 171–212 (1954).
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Geisler, W. S.

W. S. Geisler, D. G. Albrecht, “Visual cortex neurons in monkeys and cats: detection, discrimination and identification,” Visual Neurosci. 14, 897–919 (1997).
[CrossRef]

W. S. Geisler, D. G. Albrecht, “Bayesian analysis of identification performance in monkey visual cortex: nonlinear mechanisms and stimulus certainty,” Vision Res. 35, 2723–2730 (1995).
[CrossRef] [PubMed]

W. S. Geisler, L. Chou, “Separation of low-level and high-level factors in complex tasks: visual search,” Psychol. Rev. 102, 356–378 (1995).
[CrossRef] [PubMed]

Gilchrist, D.

D. Gilchrist, C. A. Heywood, J. M. Findlay, “Saccade selection in visual search: evidence for spatial frequency specific between-item interactions,” Vision Res. 39, 1373–1383 (1999).
[CrossRef] [PubMed]

Gilchrist, I. D.

J. M. Findlay, V. A. Brown, I. D. Gilchrist, “Saccade target selection in visual search: the influence of information from the previous fixation,” Vision Res. 41, 87–95 (2001).
[CrossRef] [PubMed]

Glimcher, P. W.

P. W. Glimcher, “Making choices: the neurophysiology of visual-saccadic decision making,” Trends Neurosci. 24, 654–659 (2001).
[CrossRef] [PubMed]

Goldberg, M. E.

C. L. Colby, M. E. Goldberg, “Space and attention in parietal cortex,” Annu. Rev. Neurosci. 23, 319–349 (1999).
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J. P. Gottlieb, M. Kusunoki, M. E. Goldberg, “The representation of visual salience in monkey parietal cortex,” Nature (London) 391, 481–484 (1998).
[CrossRef]

Gottlieb, J. P.

J. P. Gottlieb, M. Kusunoki, M. E. Goldberg, “The representation of visual salience in monkey parietal cortex,” Nature (London) 391, 481–484 (1998).
[CrossRef]

Green, D. M.

D. M. Green, J. A. Swets, Signal Detection Theory and Psychophysics (Wiley, New York, 1966).

Hayes, A.

R. F. Hess, A. Hayes, “The coding of spatial position by the human visual system: effects of spatial scale and retinal eccentricity,” Vision Res. 34, 625–643 (1994).
[CrossRef] [PubMed]

He, P.

P. He, E. Kowler, “The role of location probability in the programming of saccades: implications for center-of-gravity tendencies,” Vision Res. 29, 1165–1181 (1989).
[CrossRef]

Hess, R. F.

R. F. Hess, A. Hayes, “The coding of spatial position by the human visual system: effects of spatial scale and retinal eccentricity,” Vision Res. 34, 625–643 (1994).
[CrossRef] [PubMed]

Heywood, C. A.

D. Gilchrist, C. A. Heywood, J. M. Findlay, “Saccade selection in visual search: evidence for spatial frequency specific between-item interactions,” Vision Res. 39, 1373–1383 (1999).
[CrossRef] [PubMed]

Hooge, I. T.

I. T. Hooge, “Control of eye movement in visual search,” Ph.D. thesis (Utrecht University, Utrecht, The Netherlands, 1996).

Hooge, T.

T. Hooge, C. J. Erkelens, “Peripheral vision and oculomotor control during visual search,” Vision Res. 39, 1567–1575 (1999).
[CrossRef] [PubMed]

T. Hooge, C. J. Erkelens, “Adjustment of fixation duration in visual search,” Vision Res. 38, 1295–1302 (1998).
[CrossRef] [PubMed]

Jaarsma, D.

L. W. Nolte, D. Jaarsma, “More on the detection of one of M orthogonal signals,” J. Acoust. Soc. Am. 41, 497–505 (1967).
[CrossRef]

Jennings, R. J.

A. E. Burgess, R. F. Wagner, R. J. Jennings, H. B. Barlow, “Efficiency of human visual signal discrimination,” Science 214, 93–94 (1981).
[CrossRef] [PubMed]

Jürgens, R.

W. Becker, R. Jürgens, “An analysis of the saccadic system by means of double step stimuli,” Vision Res. 19, 967–983 (1979).
[CrossRef] [PubMed]

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R. M. McPeek, E. L. Keller, “Superior colliculus activity related to concurrent processing of saccade goals in a visual search task,” J. Neurophysiol. 87, 1805–1815 (2002).
[PubMed]

Kersten, D.

Kowler, E.

P. He, E. Kowler, “The role of location probability in the programming of saccades: implications for center-of-gravity tendencies,” Vision Res. 29, 1165–1181 (1989).
[CrossRef]

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R. J. Krauzlis, A. Z. Zivotofsky, F. A. Miles, “Target selection for pursuit and saccadic eye movements in humans,” J. Cogn. Neurosci. 11, 641–649 (1999).
[CrossRef] [PubMed]

Kusunoki, M.

J. P. Gottlieb, M. Kusunoki, M. E. Goldberg, “The representation of visual salience in monkey parietal cortex,” Nature (London) 391, 481–484 (1998).
[CrossRef]

Legge, G. E.

Lu, Z. L.

Maljkovic, V.

R. M. McPeek, V. Maljkovic, K. Nakayama, “Saccades require focal attention and are facilitated by a short-term memory system,” Vision Res. 39, 1555–1566 (1999).
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McPeek, R. M.

R. M. McPeek, E. L. Keller, “Superior colliculus activity related to concurrent processing of saccade goals in a visual search task,” J. Neurophysiol. 87, 1805–1815 (2002).
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R. M. McPeek, A. A. Skavenski, K. Nakayama, “Concurrent processing of saccades in visual search,” Vision Res. 40, 2499–2516 (2000).
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R. M. McPeek, V. Maljkovic, K. Nakayama, “Saccades require focal attention and are facilitated by a short-term memory system,” Vision Res. 39, 1555–1566 (1999).
[CrossRef] [PubMed]

Miles, F. A.

R. J. Krauzlis, A. Z. Zivotofsky, F. A. Miles, “Target selection for pursuit and saccadic eye movements in humans,” J. Cogn. Neurosci. 11, 641–649 (1999).
[CrossRef] [PubMed]

Miller, E. K.

L. Chelazzi, E. K. Miller, J. Duncan, R. Desimone, “A neural basis for visual search in inferior temporal cortex,” Nature (London) 363, 345–347 (1993).
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C. Motter, E. J. Belky, “The guidance of eye movements during active visual search,” Vision Res. 38, 1805–1815 (1998).
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D. J. Tolhurst, J. A. Movshon, F. A. Dean, “The statistical reliability of signals in single neurons in cat and monkey visual cortex,” Vision Res. 23, 775–785 (1983).
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Murray, R. F.

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R. M. McPeek, A. A. Skavenski, K. Nakayama, “Concurrent processing of saccades in visual search,” Vision Res. 40, 2499–2516 (2000).
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R. M. McPeek, V. Maljkovic, K. Nakayama, “Saccades require focal attention and are facilitated by a short-term memory system,” Vision Res. 39, 1555–1566 (1999).
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L. W. Nolte, D. Jaarsma, “More on the detection of one of M orthogonal signals,” J. Acoust. Soc. Am. 41, 497–505 (1967).
[CrossRef]

Palmer, J.

J. Palmer, P. Verghese, M. Pavel, “The psychophysics of visual search,” Vision Res. 40, 1227–1268 (2000).
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J. Palmer, “Set-size effects in visual search: the effect of attention is independent of the stimulus for simple tasks,” Vision Res. 34, 1703–1721 (1994).
[CrossRef] [PubMed]

Pavel, M.

J. Palmer, P. Verghese, M. Pavel, “The psychophysics of visual search,” Vision Res. 40, 1227–1268 (2000).
[CrossRef] [PubMed]

Pelli, D. G.

Peterson, W. W.

W. W. Peterson, T. G. Birdsall, W. C. Fox, “The theory of signal detectability,” IRE Trans. Inf. Theory PGIT-4, 171–212 (1954).
[CrossRef]

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J. D. Schall, K. G. Thompson, “Neural selection and control of visually guided eye movements,” Annu. Rev. Neurosci. 22, 241–259 (1999).
[CrossRef] [PubMed]

J. D. Schall, “Neural basis of saccade target selection,” Rev. Neurosci. 6, 63–85 (1995).
[CrossRef] [PubMed]

Skavenski, A. A.

R. M. McPeek, A. A. Skavenski, K. Nakayama, “Concurrent processing of saccades in visual search,” Vision Res. 40, 2499–2516 (2000).
[CrossRef] [PubMed]

Stone, L. S.

R. F. Murray, B. R. Beutter, M. P. Eckstein, L. S. Stone, “Saccadic and perceptual performance in visual search tasks. II. Letter discrimination” J. Opt. Soc. Am. A 20, 1356–1370 (2003).
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M. P. Eckstein, B. R. Beutter, L. S. Stone, “Quantifying the performance limits of human saccadic targeting during visual search,” Perception 30, 1389–1401 (2001).
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B. R. Beutter, M. P. Eckstein, L. S. Stone, “Parallel differences in contrast-discrimination and detection performance for saccades and perception in visual search,” Invest. Ophthalmol. Visual Sci. (Suppl.) 41, S424 (2000).

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Task information increases from the first to the second saccade in visual search of a target among distractors,” Invest. Ophthalmol. Visual Sci. 41, 759 (2000).

L. S. Stone, B. R. Beutter, M. P. Eckstein, “Salience effects on perceptual and saccadic target localization during search,” Soc. Neurosci. Abstr. 25, 548 (1999).

B. R. Beutter, L. S. Stone, “Human motion perception and smooth eye movements show similar directional biases for elongated apertures,” Vision Res. 38, 1273–1286 (1998).
[CrossRef] [PubMed]

B. R. Beutter, L. S. Stone, M. P. Eckstein, “Correlated saccadic and perceptual decisions in a visual-search detection task reveal spatial-filter overlap,” presented at the Vision Sciences Society Meeting, May 4–8, 2001, Sarasota, Fla., J. Vision1, No. 1 (Abstract 263) (2001), http://www.journalofvision.org/1/3/263/ .

Swensson, R. G.

P. Viviani, R. G. Swensson, “Saccadic eye movements to peripherally discriminated visual targets,” J. Exp. Psychol. Hum. Percept. Perform. 16, 459–478 (1982).

Swets, J. A.

D. M. Green, J. A. Swets, Signal Detection Theory and Psychophysics (Wiley, New York, 1966).

Thomas, J. P.

Thompson, K. G.

J. D. Schall, K. G. Thompson, “Neural selection and control of visually guided eye movements,” Annu. Rev. Neurosci. 22, 241–259 (1999).
[CrossRef] [PubMed]

Tolhurst, D. J.

D. J. Tolhurst, J. A. Movshon, F. A. Dean, “The statistical reliability of signals in single neurons in cat and monkey visual cortex,” Vision Res. 23, 775–785 (1983).
[CrossRef] [PubMed]

Verghese, P.

J. Palmer, P. Verghese, M. Pavel, “The psychophysics of visual search,” Vision Res. 40, 1227–1268 (2000).
[CrossRef] [PubMed]

Viviani, P.

P. Viviani, R. G. Swensson, “Saccadic eye movements to peripherally discriminated visual targets,” J. Exp. Psychol. Hum. Percept. Perform. 16, 459–478 (1982).

Wagner, R. F.

A. E. Burgess, R. F. Wagner, R. J. Jennings, H. B. Barlow, “Efficiency of human visual signal discrimination,” Science 214, 93–94 (1981).
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Whiting, J. S.

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M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity in superior colliculus by changes in target probability,” J. Neurosci. 18, 7519–7534 (1998).
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M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity by target uncertainty,” Nature (London) 389, 66–69 (1997).
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G. L. Zelinsky, “Using eye saccades to assess the selectivity of search movements,” Vision Res. 36, 2177–2187 (1996).
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R. J. Krauzlis, A. Z. Zivotofsky, F. A. Miles, “Target selection for pursuit and saccadic eye movements in humans,” J. Cogn. Neurosci. 11, 641–649 (1999).
[CrossRef] [PubMed]

Acta Psychol. (1)

L. G. Williams, “The effects of target specification on objects fixated during visual search,” Acta Psychol. 27, 355–360 (1966).
[CrossRef]

Annu. Rev. Neurosci. (2)

J. D. Schall, K. G. Thompson, “Neural selection and control of visually guided eye movements,” Annu. Rev. Neurosci. 22, 241–259 (1999).
[CrossRef] [PubMed]

C. L. Colby, M. E. Goldberg, “Space and attention in parietal cortex,” Annu. Rev. Neurosci. 23, 319–349 (1999).
[CrossRef]

Hum. Factors (1)

L. G. Williams, “Target conspicuity and visual search,” Hum. Factors 8, 80–92 (1967).

Invest. Ophthalmol. Visual Sci. (1)

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Task information increases from the first to the second saccade in visual search of a target among distractors,” Invest. Ophthalmol. Visual Sci. 41, 759 (2000).

Invest. Ophthalmol. Visual Sci. (Suppl.) (1)

B. R. Beutter, M. P. Eckstein, L. S. Stone, “Parallel differences in contrast-discrimination and detection performance for saccades and perception in visual search,” Invest. Ophthalmol. Visual Sci. (Suppl.) 41, S424 (2000).

IRE Trans. Inf. Theory (1)

W. W. Peterson, T. G. Birdsall, W. C. Fox, “The theory of signal detectability,” IRE Trans. Inf. Theory PGIT-4, 171–212 (1954).
[CrossRef]

J. Acoust. Soc. Am. (1)

L. W. Nolte, D. Jaarsma, “More on the detection of one of M orthogonal signals,” J. Acoust. Soc. Am. 41, 497–505 (1967).
[CrossRef]

J. Cogn. Neurosci. (1)

R. J. Krauzlis, A. Z. Zivotofsky, F. A. Miles, “Target selection for pursuit and saccadic eye movements in humans,” J. Cogn. Neurosci. 11, 641–649 (1999).
[CrossRef] [PubMed]

J. Exp. Psychol. Hum. Percept. Perform. (1)

P. Viviani, R. G. Swensson, “Saccadic eye movements to peripherally discriminated visual targets,” J. Exp. Psychol. Hum. Percept. Perform. 16, 459–478 (1982).

J. Neurophysiol. (1)

R. M. McPeek, E. L. Keller, “Superior colliculus activity related to concurrent processing of saccade goals in a visual search task,” J. Neurophysiol. 87, 1805–1815 (2002).
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J. Neurosci. (1)

M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity in superior colliculus by changes in target probability,” J. Neurosci. 18, 7519–7534 (1998).
[PubMed]

J. Opt. Soc. Am. (1)

J. Opt. Soc. Am. A (8)

Nature (London) (3)

M. A. Basso, R. H. Wurtz, “Modulation of neuronal activity by target uncertainty,” Nature (London) 389, 66–69 (1997).
[CrossRef]

J. P. Gottlieb, M. Kusunoki, M. E. Goldberg, “The representation of visual salience in monkey parietal cortex,” Nature (London) 391, 481–484 (1998).
[CrossRef]

L. Chelazzi, E. K. Miller, J. Duncan, R. Desimone, “A neural basis for visual search in inferior temporal cortex,” Nature (London) 363, 345–347 (1993).
[CrossRef]

Perception (1)

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Quantifying the performance limits of human saccadic targeting during visual search,” Perception 30, 1389–1401 (2001).
[CrossRef]

Proc. R. Soc. London (1)

H. B. Barlow, “The absolute efficiency of perceptual decisions,” Proc. R. Soc. London 290, 71–91 (1980).

Psychol. Rev. (1)

W. S. Geisler, L. Chou, “Separation of low-level and high-level factors in complex tasks: visual search,” Psychol. Rev. 102, 356–378 (1995).
[CrossRef] [PubMed]

Psychol. Sci. (1)

M. P. Eckstein, “The lower efficiency for conjunctions is due to noise and not serial visual attention,” Psychol. Sci. 9, 111–118 (1998).
[CrossRef]

Rev. Neurosci. (1)

J. D. Schall, “Neural basis of saccade target selection,” Rev. Neurosci. 6, 63–85 (1995).
[CrossRef] [PubMed]

Science (1)

A. E. Burgess, R. F. Wagner, R. J. Jennings, H. B. Barlow, “Efficiency of human visual signal discrimination,” Science 214, 93–94 (1981).
[CrossRef] [PubMed]

Soc. Neurosci. Abstr. (1)

L. S. Stone, B. R. Beutter, M. P. Eckstein, “Salience effects on perceptual and saccadic target localization during search,” Soc. Neurosci. Abstr. 25, 548 (1999).

Trends Neurosci. (1)

P. W. Glimcher, “Making choices: the neurophysiology of visual-saccadic decision making,” Trends Neurosci. 24, 654–659 (2001).
[CrossRef] [PubMed]

Vision Res. (17)

P. He, E. Kowler, “The role of location probability in the programming of saccades: implications for center-of-gravity tendencies,” Vision Res. 29, 1165–1181 (1989).
[CrossRef]

R. F. Hess, A. Hayes, “The coding of spatial position by the human visual system: effects of spatial scale and retinal eccentricity,” Vision Res. 34, 625–643 (1994).
[CrossRef] [PubMed]

R. M. McPeek, V. Maljkovic, K. Nakayama, “Saccades require focal attention and are facilitated by a short-term memory system,” Vision Res. 39, 1555–1566 (1999).
[CrossRef] [PubMed]

D. Gilchrist, C. A. Heywood, J. M. Findlay, “Saccade selection in visual search: evidence for spatial frequency specific between-item interactions,” Vision Res. 39, 1373–1383 (1999).
[CrossRef] [PubMed]

B. R. Beutter, L. S. Stone, “Human motion perception and smooth eye movements show similar directional biases for elongated apertures,” Vision Res. 38, 1273–1286 (1998).
[CrossRef] [PubMed]

R. M. McPeek, A. A. Skavenski, K. Nakayama, “Concurrent processing of saccades in visual search,” Vision Res. 40, 2499–2516 (2000).
[CrossRef] [PubMed]

W. Becker, R. Jürgens, “An analysis of the saccadic system by means of double step stimuli,” Vision Res. 19, 967–983 (1979).
[CrossRef] [PubMed]

D. J. Tolhurst, J. A. Movshon, F. A. Dean, “The statistical reliability of signals in single neurons in cat and monkey visual cortex,” Vision Res. 23, 775–785 (1983).
[CrossRef] [PubMed]

W. S. Geisler, D. G. Albrecht, “Bayesian analysis of identification performance in monkey visual cortex: nonlinear mechanisms and stimulus certainty,” Vision Res. 35, 2723–2730 (1995).
[CrossRef] [PubMed]

J. M. Findlay, “Saccade target selection during visual search,” Vision Res. 37, 617–631 (1997).
[CrossRef] [PubMed]

C. Motter, E. J. Belky, “The guidance of eye movements during active visual search,” Vision Res. 38, 1805–1815 (1998).
[CrossRef] [PubMed]

T. Hooge, C. J. Erkelens, “Adjustment of fixation duration in visual search,” Vision Res. 38, 1295–1302 (1998).
[CrossRef] [PubMed]

T. Hooge, C. J. Erkelens, “Peripheral vision and oculomotor control during visual search,” Vision Res. 39, 1567–1575 (1999).
[CrossRef] [PubMed]

J. M. Findlay, V. A. Brown, I. D. Gilchrist, “Saccade target selection in visual search: the influence of information from the previous fixation,” Vision Res. 41, 87–95 (2001).
[CrossRef] [PubMed]

G. L. Zelinsky, “Using eye saccades to assess the selectivity of search movements,” Vision Res. 36, 2177–2187 (1996).
[CrossRef] [PubMed]

J. Palmer, “Set-size effects in visual search: the effect of attention is independent of the stimulus for simple tasks,” Vision Res. 34, 1703–1721 (1994).
[CrossRef] [PubMed]

J. Palmer, P. Verghese, M. Pavel, “The psychophysics of visual search,” Vision Res. 40, 1227–1268 (2000).
[CrossRef] [PubMed]

Visual Neurosci. (1)

W. S. Geisler, D. G. Albrecht, “Visual cortex neurons in monkeys and cats: detection, discrimination and identification,” Visual Neurosci. 14, 897–919 (1997).
[CrossRef]

Other (11)

One should note that when applying the uncertainty equation19to a contrast-discrimination task, one should interpret Uas the effect of uncertainty on performance rather than the number of statistically independent signal-irrelevant responses monitored by the observer. In addition to the discriminability (d1)of the signal with respect to the distractors, an alternative model for the contrast-discrimination task would take into account the discriminability (d2)of the signal with respect to the Uadditional signal-irrelevant mechanisms. This more complete formulation is given by PC=100∫-∞+∞dx[g(x)G(x+d1′)N-1G(x+d2′)UN+Ug(x+d2′)G(x)G(x+d1′)N-1G(x+d2′)UN1],where g(x)is the Gaussian density function, G(x)is the cumulative probability, Uis the number of additional signal-irrelevant mechanisms per location monitored, and Nis the number of possible target locations. This model has two fitting parameters and would require a separate experiment to estimate d2′.Note that if d2′is large, as in the contrast-discrimination task (>2.5 approximately), the irrelevant mechanisms almost never produce the largest response, and increasing Uin the equation above has very little effect on PC.

M. P. Eckstein, B. R. Beutter, L. S. Stone, “Accumulation of information across saccades during visual search depends on how far the first saccade lands from the target,” Perception (Suppl.)29 (2000), http://www.perceptionweb.com/perception/ecvp00/0029.html .

I. T. Hooge, “Control of eye movement in visual search,” Ph.D. thesis (Utrecht University, Utrecht, The Netherlands, 1996).

D. G. Pelli, “Effects of visual noise,” Ph.D. thesis (Cambridge University, Cambridge, UK, 1981).

This decision strategy is suboptimal, as discussed in Pelli,16but approximates the ideal decision at high SNRs,32although for the parameters that we use the difference in performance is small.

An alternative model has been proposed by Lu and Dosher29in which a nonlinear transducer replaces the intrinsic uncertainty.

The SNRs are slightly different for the discrimination and detection stimuli because we measured each SNR from the stimuli actually used in the experiment rather than relying on the ensemble parameters used to generate the stimuli.

D. M. Green, J. A. Swets, Signal Detection Theory and Psychophysics (Wiley, New York, 1966).

B. R. Beutter, L. S. Stone, M. P. Eckstein, “Correlated saccadic and perceptual decisions in a visual-search detection task reveal spatial-filter overlap,” presented at the Vision Sciences Society Meeting, May 4–8, 2001, Sarasota, Fla., J. Vision1, No. 1 (Abstract 263) (2001), http://www.journalofvision.org/1/3/263/ .

B. R. Beutter, M. P. Eckstein, L. S. Stone, “Similar internal noise levels limit saccadic and perceptual performance in a visual-search task,” Program No. 418. 13 (2002). Abstract Viewer/Itinerary Planner. Society for Neuroscience, Washington, D.C., 2002. Online. http://sfn.scholarone.com/itin2002/index.html .

This definition compares human- and ideal-observer performances at the same SNR. As suggested by a reviewer, it is also possible to define efficiency as a comparison between the human- and ideal-observer SNRs required to achieve the same performance level. In this alternative definition, efficiency is equal to (SNRideal/SNRhuman)2.The two definitions are equivalent if human d′is directly proportional to SNR (uncertainty is equal to zero), as is the case for our discrimination task. They are not the same for nonzero uncertainty (nonzero intercept), as is the case for our detection task.

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Figures (9)

Fig. 1
Fig. 1

(a) Example of a stimulus image for the contrast-detection experiment. The nontarget boxes contain only noise, while the target box has a low-contrast disk added to the noise. (b) Example of a stimulus image for the contrast-discrimination experiments. The nontarget boxes each contain distractors of equal contrast, while the target box has a higher-contrast disk. (c) Eye movement data from an “easy” trial (SNR=6.3) in the contrast-detection experiment for observer JL. This trial contained a single saccade to the target box, so the first saccadic decision was correct. (d) Eye movement data from a “difficult” trial (SNR=2.0) in the contrast-detection experiment for observer JL. This trial contained eight saccades. The first saccade was to a distractor box, so the first saccadic decision was incorrect. The second, sixth, and last saccades were to the target box.

Fig. 2
Fig. 2

Effects of the two fitted parameters, alpha (α) and uncertainty (U), on the model predictions. The top graph shows the effect of U on detectability for α=0.5. The bottom graph shows the effect of α on detectability for U=4.

Fig. 3
Fig. 3

Median saccadic latencies (EM condition) as a function of SNR for the detection (open symbols) and discrimination (solid symbols) tasks for each of the three observers. In this figure, the latencies for correct and incorrect saccadic decisions have been combined.

Fig. 4
Fig. 4

Histograms of the saccadic latencies (EM condition) for correct (solid circles) and incorrect (open squares) saccadic decisions for each of the three observers (bin size is 25 ms). In this figure, the latencies for the different SNRs have been combined.

Fig. 5
Fig. 5

Proportion of correct decisions for the discrimination (solid circles) and detection (open squares) tasks for observer JL (error bars represent standard errors): (a) accuracy of the perceptual decision in the fixation (FIX) condition, (b) accuracy of the first saccadic decision in the EM condition, (c) accuracy of the final perceptual decision in the EM condition.

Fig. 6
Fig. 6

Accuracy of the FIX and EM perceptual decisions and the first saccadic decision for both the detection and discrimination tasks. The accuracy in d units is plotted as a function of SNR. The solid circles show the accuracy of the first saccadic decision, the open squares show the perceptual accuracy in the FIX condition, and the open triangles show the perceptual accuracy in the long-duration EM condition. The lines through the points are optimal fits of the signal detection uncertainty model. Error bars show the standard error of the mean.

Fig. 7
Fig. 7

Absolute efficiencies for (FIX) perception and saccades plotted as a function of SNR for the three observers. The model predictions are shown as the curves [perception (solid), saccades (dashed)]. For the detection task, efficiency increased as SNR increased, while for the discrimination task, efficiency was nearly constant as a function of SNR.

Fig. 8
Fig. 8

Maximum-likelihood values [from the fits to Eq. (A7)] of the slope parameter (α) for FIX perception and saccades. Error bars represent 95% confidence intervals. For both saccades (solid symbols) and perception (open symbols), the slopes for detection were higher than those for discrimination.

Fig. 9
Fig. 9

Maximum-likelihood values [from the fits to Eq. (A7)] of the uncertainty number (U) for the detection task for FIX perception (open bars) and the first saccade (solid bars). Error bars represent 95% confidence intervals. For the discrimination task, the best-fitting uncertainty was zero for all observers for the saccadic data and both sets of perceptual data (data not shown).

Equations (16)

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PC(d, N)=100(2π)-1/2-+dx exp-(x-d)22×[erf(x)]N-1.
d=(uS-uD)σ=α×SNR.
Ri=x,yt(x, y)ci(x, y).
dI=μT-μDσR=AT-ADσE=SNR,
PC(d, N)=-+dxP(RT=x)P(allRD<x),
PC(d, N)=100(2π)-N/2-+dx exp(x-d)22×-xdy expy22N-1.
dH=(AT-AD)x,yf(x, y)t(x, y)σE2+σi2=SNR×x,yf(x, y)t(x, y)[1+(σi2/σE2)]1/2.
α=x,yf(x, y)t(x, y)[1+(σi2/σE2)]1/2.
x,yfi(x, y)fj(x, y)=0forij.
x,yfi(x, y)t(x, y)=0forallexceptonemechanism.
PC(d, N)=100(2π)-N(U+1)/2-+dx exp(x-d)22×-xdy expy22N(U+1)-1+100U(2π)-N(U+1)/2-+dx expx22×-xdy expy22N(U+1)-2×-xdz exp(z-d)22,
d=SNR×x,yf(x, y)t(x, y)[1+(σi2/σE2)]1/2=α×SNR.
Absoluteefficiency=(dhuman/dideal)2.
Absoluteefficiency=x,yf(x, y)t(x, y)[1+(σi2/σE2)]1/22.
Relativeefficiency=(ddecision1/ddecision2)2.
PC=100-+dx[g(x)G(x+d1)N-1G(x+d2)UN+Ug(x+d2)G(x)G(x+d1)N-1G(x+d2)UN1],

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