Skip to main content
Log in

Two spatio-temporal filters in human vision

2. Selective modification in amblyopia, albinism, and hemianopia

  • Published:
Biological Cybernetics Aims and scope Submit manuscript

Abstract

1. We have used the psychophysical methods described in the first paper of this series (Holliday and Ruddock, 1983) to determine selected spatial and temporal response characteristics of the ST1 and ST2 filters for subjects suffering visual defects. Data are given for 19 amblyopes, an albino and a hemianope, and comparison data are also given for a number of subjects with normal vision. 2. The ST1 spatial responses for both the “normal” and “amblyopic” eyes of 12 convergent strabismic amblyopes are displaced to low spatial frequencies compared to the normal curve, which implies that there is a loss of fine spatial tuning. In all but one subject, the curve for the “amblyopic” eye peaks at a spatial frequency lower than that for the “normal” eye, thus the former deviates further from the normal pattern than the latter. 3. The ST1 spatial responses of 6 refractive amblyopes are also displaced to the low frequency side of the normal curve, although on average the shift is smaller than in the case of the strabismic amblyopes. For each subject, the response curve of the “amblyopic” eye peaks at a lower spatial frequency than does that for the “normal” eye. 4. ST1 spatial responses were measured for targets located up to 30° off-axis along the horizontal meridian and sample data are given for one strabismic and one refractive amblyope and for two normal subjects. It is concluded from these data that the changes in the spatial responses associated with amblyopia do not simply reflect eccentric fixation of the target. 5. The ST2 spatial response was measured for the “normal” and “amblyopic” eyes of 9 amblyopes, (7 stabismic and 2 refractive). There is no significant difference between the average amblyopic response and that of, normal subjects, and only in one case does the response for an “amblyopic” eye peak at a frequency lower than the peak frequency for normal vision. 6. The ST2 temporal response for 9 amblyopes shows no systematic deviations from the normal response. 7. For the albino, both the ST1 and ST2 spatial responses peak at around 0.3 cycles deg-1, and both curves are displaced considerably to the low spatial frequency side of the normal ST2 spatial response. The albino's ST2 temporal response is essentially normal. 8. Measurements for the hemianope's “blind” hemifield under conditions appropriate to the isolation of the ST1 and ST2 spatial responses reveal no tuning curves. The ST2 temporal response for the “blind” hemifield, however, is of large amplitude, with a peak at 2 Hz, well below the normal frequency response peak. 9. It is argued that the loss of fine spatial tuning which occurs in the ST1, but not the ST2, spatial responses of the amblyopes is consistent with the sequential organisation of these two filter classes proposed by Holliday and Ruddock (1983). Further, for the only two subjects whose ST2 spatial response curves are displaced to abnormally low frequencies (the albino and a strabismic amblyope) the ST1 spatial response is shifted to low spatial frequencies compared to the normal ST2 curve. This is also consistent with Holliday and Ruddock's (1983) model.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Barbur, J.L., Ruddock, K.H.: Spatial characteristics ofmovement detection mechanisms in human vision. 1. Achromatic mechanisms. Biol. Cybern. 37, 77–92 (1980)

    Google Scholar 

  • Barbur, J.L., Ruddock, K.H., Waterfield, V.A.: Human visual responses in the absence of the geniculo-calcarine projection. Brain 103, 905–928 (1980)

    Google Scholar 

  • Barbur, J.L., Holliday, I.E., Ruddock, K.H., Waterfield, V.A.: Spatial characteristics of movement detection mechanisms in human vision. III. Subjects with abnormal visual pathways. Biol. Cybern. 37, 99–105 (1980)

    Google Scholar 

  • Cleland, B.E., Crewther, D.P., Crewther, S.G., Mitchell, D.E.: Normality of spatial resolution of retinal ganglion cells in cats with strabismic amblyopia. J. Physiol. (London) 326, 235–249 (1982)

    Google Scholar 

  • Hess, R.F., Howell, E.R.: The threshold contrast sensitivity function in strabismic amblyopia. Evidence for a two type classification. Vision Res. 17, 1049–1055 (1977)

    Google Scholar 

  • Hess, R.F., Bradley, A.: Contrast perception above threshold is only minimally impaired in human amblyopia. Nature 287, 463–464 (1980)

    Google Scholar 

  • Hess, R.F., Campbell, F.W., Zimmern, R.: Differences in the neural basis of amblyopias: the effect of mean luminance. Vision Res. 20, 295–306 (1980)

    Google Scholar 

  • Holliday, I.E., Ruddock, K.H.: Two spatio-temporal filters in human vision. 1. Temporal and spatial frequency response characteristics. Biol. Cybern. 47, 173–190 (1983)

    Google Scholar 

  • Ikeda, H.: Visual acuity-its development and amblyopia. Edridge-Green Lecture 1979. J. R. Soc. Med. 73, 546–555 (1980)

    Google Scholar 

  • Ikeda, H., Tremain, K.E.: Development of spatial resolving power of laternal geniculate neurones in kittens. Exp. Brain. Res. 31, 193–206 (1978)

    Google Scholar 

  • Ikeda, H., Tremain, K.E.: Amblyopia occurs, in retinal ganglion cells of cats reared with convergent squint without alternating fixation. Exp. Brain Res. 35, 559–582 (1979)

    Google Scholar 

  • Ikeda, H., Tremain, K.E., Einion, O.: Loss of spatial resolution of lateral geniculate, neurones in kittens reared with convergent squint produced at different stages of development. Exp. Brain Res. 31, 207–220 (1978)

    Google Scholar 

  • Lyle, T.K., Wybar, K.C.: Lyle and Jackson's practical orthoptics in the treatment of squint (and other anomalies of binocular vision) (5th edn.) I. K. Lewis, London, 1967

    Google Scholar 

  • Miles, P.W.: Flicker fusion frequency in amblyopia, ex anopsia. Am. J. Opthalnol. 32, 225–231 (1949)

    Google Scholar 

  • Phillips, G.: Perception of flicker in lesions of visual pathways. Brain 56, 464–478 (1933)

    Google Scholar 

  • Ruddock, K.H.: Psychophysical studies on subjects with visual defects. The Edrdge-Green Lecture 1981. J. R. Soc. Med. 75, 315–322 (1982)

    Google Scholar 

  • Wilson, M.E.: Spatial and temporal summation in impaired regions of the visual field. J. Physiol. (London) 189, 189–208 (1967)

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Grounds, A.R., Holliday, I.E. & Ruddock, K.H. Two spatio-temporal filters in human vision. Biol. Cybern. 47, 191–201 (1983). https://doi.org/10.1007/BF00337008

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF00337008

Keywords

Navigation