Direct comparison of category and spatial selectivity in human occipitotemporal cortex

Human visual cortex is organised broadly according to two major principles: retinotopy (the spatial mapping of the retina in cortex) and category-selectivity (preferential responses to specific categories of stimuli). Historically, these principles were considered anatomically separate, with retinotopy restricted to the occipital cortex and category-selectivity emerging in lateral-occipital and ventral-temporal cortex. Contrary to this assumption, recent studies show that category-selective regions exhibit systematic retinotopic biases. It is unclear, however, whether responses within these regions are more strongly driven by retinotopic location or by category preference, and if there are systematic differences between category-selective regions in the relative strengths of these preferences. Here, we directly compare spatial and category preferences by measuring fMRI responses to scene and face stimuli presented in the left or right visual field and computing two bias indices: a spatial bias (response to the contralateral minus ipsilateral visual field) and a category bias (response to the preferred minus non-preferred category). We compare these biases within and between scene- and face-selective regions across the lateral and ventral surfaces of visual cortex. We find an interaction between surface and bias: lateral regions show a stronger spatial than category bias, whilst ventral regions show the opposite. These effects are robust across and within subjects, and reflect large-scale, smoothly varying gradients across both surfaces. Together, these findings support distinct functional roles for lateral and ventral category-selective regions in visual information processing in terms of the relative importance of spatial information.

Exogenous Endowment—Endogenous Reference Point

We develop a model in the presence of categories that creates a link between the agent’s exogenous endowment and an endogenous reference point. The reference point is the best feasible alternative in the endowment’s category. This reference generates a constraint set from which the final choice is made according to utility maximisation. The model predicts category bias, which generalises the status quo bias by attracting the agent to her endowment’s category but not necessarily to the endowment itself. We show that it accommodates recent experimental findings regarding the presence and absence of status quo bias in the realm of uncertainty. In a stylised financial setup, we show that it may lead to a risk premium even with risk-neutral agents.