Contrast sensitivity in human visual areas and its relationship to object recognition.

@article{Avidan2002ContrastSI,
  title={Contrast sensitivity in human visual areas and its relationship to object recognition.},
  author={Galia Avidan and Michal Harel and Talma Hendler and Dafna Ben-Bashat and Ehud Zohary and Rafael Malach},
  journal={Journal of neurophysiology},
  year={2002},
  volume={87 6},
  pages={
          3102-16
        }
}
An important characteristic of visual perception is the fact that object recognition is largely immune to changes in viewing conditions. This invariance is obtained within a sequence of ventral stream visual areas beginning in area V1 and ending in high order occipito-temporal object areas (the lateral occipital complex, LOC). Here we studied whether this transformation could be observed in the contrast response of these areas. Subjects were presented with line drawings of common objects and… 
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References

SHOWING 1-10 OF 64 REFERENCES

A sequence of object‐processing stages revealed by fMRI in the human occipital lobe

Functional magnetic resonance imaging was used in combined functional selectivity and retinotopic mapping tests to reveal object‐related visual areas in the human occpital lobe and suggest the existence of object‐fragment representation in LO.

Object-completion effects in the human lateral occipital complex.

The fMRI results point to the lateral occipital complex as a central site in which object completion effects are manifested, and the cortical regions showing the highest 'completion' effects co-localized with regions in the LOC which showed the highest activation to the 'whole' images compared to the'scrambled' images.

A hierarchical axis of object processing stages in the human visual cortex.

The results suggest the existence of a hierarchical axis along ventral occipito-temporal object-areas, in which the neuronal properties shift from sensitivity to local object features to a more global and holistic representation.

Retinotopy and color sensitivity in human visual cortical area V8

The location of the human color-selective region did not match the location of area V4 (neither its dorsal nor ventral subdivisions), as extrapolated from macaque maps, and instead this region coincides with a new retinotopic area that is called 'V8', which includes a distinct representation of the fovea and both upper and lower visual fields.

Size and position invariance of neuronal responses in monkey inferotemporal cortex.

The size-specific responses observed in 43% of the cells are consistent with recent psychophysical data that suggest that images of objects are stored in a size- specific manner in the long-term memory, and both size-dependent and -independent processing of images may occur in anterior IT.

Cue-Invariant Activation in Object-Related Areas of the Human Occipital Lobe

Vase or face? A neural correlate of shape-selective grouping processes in the human brain

A modified Rubin vase-face illusion was employed to explore to what extent the activation in face-related regions is attributable to the presence of local face features, or is due to a more holistic grouping process that involves the entire face figure.

Contrast gain control in the cat visual cortex

The results show that, for the majority of cortical neurones, response–contrast curves are laterally shifted along a log-contrast axis so that the effective domains of neurones are adjusted to match prevailing contrast levels.

Representation of Perceived Object Shape by the Human Lateral Occipital Complex

Adaptation in the LOC is found when perceived shape was identical but contours differed, but not when contours were identical but perceived shape differed, indicating that the LOC represents not simple image features, but rather higher level shape information.

The Representation of Illusory and Real Contours in Human Cortical Visual Areas Revealed by Functional Magnetic Resonance Imaging

Physiological signals obtained from human visual cortex while subjects viewed different types of contours suggest a role in surface perception for this lateral occipital region that includes V3A, V4v, V7, and V8 and finds evidence for overlapping sites of processing.
...