Abstract

Campbell and Robson [ J. Physiol. (London) 197, 551 ( 1968)] proposed that a near-threshold square-wave grating can be distinguished from a sine-wave grating of the same spatial frequency and fundamental amplitude when the channel tuned to the third-harmonic component of the square wave reaches its own threshold. To test this hypothesis, we measured waveform discrimination thresholds with two-interval forced-choice methods before and after 4-min adaptation to a high-contrast sine-wave grating, the spatial frequency of which equaled that of the square wave’s third harmonic. The results indicate that 3f adaptation has only a negligible effect on discrimination thresholds. In a further experiment, we adapted observers to both 3f and 5f harmonic frequencies of the square-wave test grating presented sequentially over 4 min. Although substantial threshold elevations occurred at the 3f and 5f frequencies, the elevation in waveform discrimination threshold was small. These results suggest that the independent-channel hypothesis alone cannot account for the visibility of complex features (edges) following harmonic adaptation.

© 1988 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Spatial-frequency discrimination and detection: comparison of postadaptation thresholds

D. Regan and K. I. Beverley
J. Opt. Soc. Am. 73(12) 1684-1690 (1983)

Masking of spatial-frequency discrimination

D. Regan
J. Opt. Soc. Am. A 2(7) 1153-1159 (1985)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (2)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (1)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription