9 research outputs found
Shape similarity, better than semantic membership, accounts for the structure of visual object representations in a population of monkey inferotemporal neurons
The anterior inferotemporal cortex (IT) is the highest stage along the hierarchy of visual areas that, in primates, processes visual objects. Although several lines of evidence suggest that IT primarily represents visual shape information, some recent studies have argued that neuronal ensembles in IT code the semantic membership of visual objects (i.e., represent conceptual classes such as animate and inanimate objects). In this study, we investigated to what extent semantic, rather than purely visual information, is represented in IT by performing a multivariate analysis of IT responses to a set of visual objects. By relying on a variety of machine-learning approaches (including a cutting-edge clustering algorithm that has been recently developed in the domain of statistical physics), we found that, in most instances, IT representation of visual objects is accounted for by their similarity at the level of shape or, more surprisingly, low-level visual properties. Only in a few cases we observed IT representations of semantic classes that were not explainable by the visual similarity of their members. Overall, these findings reassert the primary function of IT as a conveyor of explicit visual shape information, and reveal that low-level visual properties are represented in IT to a greater extent than previously appreciated. In addition, our work demonstrates how combining a variety of state-of-the-art multivariate approaches, and carefully estimating the contribution of shape similarity to the representation of object categories, can substantially advance our understanding of neuronal coding of visual objects in cortex
First Nations children
The editorial “Every child deserves a home”1 does not mention that First Nations children are six to eight times more likely to be in child welfare care. The factors driving the over-represen-tation of First Nations children in care (poverty, poor housing, substance mis-use by caregivers) are responsive to services, but equitable funding is needed to address the problem.2 There is growing evidence that successful adoption placements must fully respect a child’s cultural and linguistic iden-tity. Despite this, the federal govern-ment provides no funding to First Nations on reserve for adoption pro-grams, even though pilot adoption pro-grams created by First Nations have won numerous international awards of excellence. Residential schools have closed, but sadly, many of the federal government’s policies undermining First Nations children continue to flourish