Human object recognition and classification depend on the retinal location where the object is presented and decrease as eccentricity increases. The lateral occipital complex (LOC) is thought to be preferentially involved in the processing of objects, and its neural responses exhibit category biases to objects presented in the central visual field. However, the nature of LOC neural responses to central and peripheral objects remains largely unclear. In the present study, we used functional magnetic resonance imaging (fMRI) and a wide-view presentation system to investigate neural responses to four categories of objects (faces, houses, animals, and cars) in the primary visual cortex (V1) and the lateral visual cortex, including the LOC and the retinotopic areas LO-1 and LO-2. In these regions, the neural responses to objects decreased as the distance between the location of presentation and center fixation increased, which is consistent with the diminished perceptual ability that was found for peripherally presented images. The LOC and LO-2 exhibited significantly positive neural responses to all eccentricities (0–55°), but LO-1 exhibited significantly positive responses only to central eccentricities (0–22°). By measuring the ratio relative to V1 (RRV1), we further demonstrated that eccentricity, category and the interaction between them significantly affected neural processing in these regions. LOC, LO-1, and LO-2 exhibited larger RRV1s when stimuli were presented at an eccentricity of 0° compared to when they were presented at the greater eccentricities. In LOC and LO-2, the RRV1s for images of faces, animals and cars showed an increasing trend when the images were presented at eccentricities of 11 to 33°. However, the RRV1s for houses showed a decreasing trend in LO-1 and no difference in the LOC and LO-2. We hypothesize, that when houses and the images in the other categories were presented in the peripheral visual field, they were processed via different strategies in the lateral visual cortex.

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The present study examined the coding of retinal eccentricity spatial position in object selective cortex. Using a wide-view (about 120°) visual presentation system developed for vision research and functional magnetic resonance imaging (fMRI), the subject were presented with object, which were presented at a range of viewpoints in 6 level of eccentricity degree. We investigated the BLOD response to stimuli in two regions in the ventral visual cortex (V1) and Lateral Occipital Complex (LOC). The analysis further revealed the weaker BLOD response in the bigger eccentricity in both V1 and LOC areas. However, the activation to objects were quiet different in the cortex region. The V1 areas had flatter decreasing response as eccentricity increasing. However, V1 had bigger response in 11° eccentricity. And the LOC areas had neural activities decreasing sharply as eccentricity increasing. The result suggests reflected the neural response character influenced by eccentricity and stimuli cartage.

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