Cortical circuits can flexibly change with experience and learning, but the effects on specific cell types, including distinct inhibitory types, are not well understood. Here we investigated how ...excitatory and VIP inhibitory cells in layer 2/3 of mouse visual cortex were impacted by visual experience in the context of a behavioral task. Mice learned a visual change detection task with a set of eight natural scene images. Subsequently, during 2-photon imaging experiments, mice performed the task with these familiar images and three sets of novel images. Strikingly, the temporal dynamics of VIP activity differed markedly between novel and familiar images: VIP cells were stimulus-driven by novel images but were suppressed by familiar stimuli and showed ramping activity when expected stimuli were omitted from a temporally predictable sequence. This prominent change in VIP activity suggests that these cells may adopt different modes of processing under novel versus familiar conditions.
The maintenance of short-term memories is critical for survival in a dynamically changing world. Previous studies suggest that this memory can be stored in the form of persistent neural activity or ...using a synaptic mechanism, such as with short-term plasticity. Here, we compare the predictions of these two mechanisms to neural and behavioral measurements in a visual change detection task. Mice were trained to respond to changes in a repeated sequence of natural images while neural activity was recorded using two-photon calcium imaging. We also trained two types of artificial neural networks on the same change detection task as the mice. Following fixed pre-processing using a pretrained convolutional neural network, either a recurrent neural network (RNN) or a feedforward neural network with short-term synaptic depression (STPNet) was trained to the same level of performance as the mice. While both networks are able to learn the task, the STPNet model contains units whose activity are more similar to the in vivo data and produces errors which are more similar to the mice. When images are omitted, an unexpected perturbation which was absent during training, mice often do not respond to the omission but are more likely to respond to the subsequent image. Unlike the RNN model, STPNet produces a similar pattern of behavior. These results suggest that simple neural adaptation mechanisms may serve as an important bottom-up memory signal in this task, which can be used by downstream areas in the decision-making process.
Visual cortex is organized into discrete sub-regions or areas that are arranged into a hierarchy and serves different functions in the processing of visual information. In retinotopic maps of mouse ...cortex, there appear to be substantial mouse-to-mouse differences in visual area location, size and shape. Here we quantify the biological variation in the size, shape and locations of 11 visual areas in the mouse, after separating biological variation and measurement noise. We find that there is biological variation in the locations and sizes of visual areas.
Despite sustained scholarly interest in post‐conflict states, there has not been a thorough review and analysis of associated methodology and the challenges of conducting research in these contexts. ...Addressing this gap, this paper directs attention to the particular effects of these settings on access and data quality and their ramifications for the resulting scholarship. It assesses the intrinsic challenges of performing fieldwork in these environments, drawing on both relevant social science literature and the authors’ experiences of carrying out research in Afghanistan and Timor‐Leste. The study demonstrates that the post‐conflict environment moulds research design and, consequently, influences how questions are answered as well as the questions asked. Moreover, it highlights ways to mitigate these issues. This work is of relevance to scholars planning to engage in field research and to researchers reflecting upon their work, as well as to policymakers who are considering undertaking programmes or commissioning research in post‐conflict areas.
Much has been made of the 'imperial' influence of international actors (Chopra 2000) and their view of Timor-Leste as a petri dish for post-conflict development. However, this view obscures the ways ...in which conflict-era actors and their networks shape core decision regarding resource allocation. This article examines the political economies of resistance-era networks in the post-conflict period, focusing specifically on the large-scale pensions programme. The article argues that these former fighters tasked with registration verification serve as 'street level bureaucrats' and have re-shaped the programme to reflect their views of the conflict and interests. This is not a trivial matter - in 2015 the programme consumed 9 per cent of the national budget - and this work suggests that pensions should be viewed as a core aspect of post-conflict economic development in Timor-Leste and, more broadly, that the role of conflict actors in defining such programmes is essential to understanding redistributive policies after conflict.
Over the last decade, the bottom-of-the-pyramid (BoP) approach has gained prominence as a tool of "inclusive" capitalism in sub-Saharan Africa. This approach reframes development as a seamless ...outcome of core business activities, one that can ameliorate poverty by bringing much-needed products and services to the poor and generating employment opportunities for informal and subsistence workers as "micro-entrepreneurs." Yet while transnational capital has set its sights on Africa's "underserved" yet potentially buoyant markets, BoP initiatives do more than seize upon the entrepreneurial talent and aspirations of Africa's informal economies. This article argues, rather, that these initiatives create BoP economies through a set of market technologies, practices, and discourses that render the spaces and actors at the bottom of the pyramid knowable, calculable, and predictable to global business. The article describes how these technologies extend new forms of market governance over the informal poor, reconfiguring their habits, social practices, and economic strategies under the banner of poverty reduction. Au cours des dix dernières années, une approche dite "par le bas" a gagné de l'importance comme outil dans l'expansion d'un capitalisme "inclusif" en Afrique sub-saharienne. Cette approche recadre la notion de développement comme un aboutissement naturel d'activités commerciales essentielles, pouvant améliorer le niveau de pauvreté en apportant des produits et des services de nécessité aux gens dans le besoin et en employant des ouvriers du secteur informel et de subsistance comme "micro-entrepreneurs." Cependant, alors que la capitale transnationale s'intéresse aux marchés "sous-exploités" quoique prometteurs, les initiatives du Bas de la Pyramide (BOP) font plus que profiter des talents entrepreneuriaux et des aspirations des économies informelles africaines. Cet article soutient que bien au contraire, ces initiatives créent les économies BOP à travers un certain nombre de technologies de vente, de pratiques établies, et de discours qui permettent de connaître les espaces et les acteurs du BOP, de les quantifier et de les prédire pour les besoins du marché mondial. Cet article décrit comment ces technologies, pour réduire la pauvreté, mettent de nouvelles formes de gouvernance du marché à la portée des plus démunis, faisant ainsi évoluer leurs habitudes, leurs configurations sociales et leurs stratégies économiques.
ABSTRACT
Untapped markets are often deemed institutional voids, terra incognita ripe with economic possibility. The conversion of institutional voids into viable markets has become the ambition of ...many corporations today, which view marginal and under‐served areas such as urban slums as opportunities to achieve the dual aims of market growth and poverty reduction, particularly through ‘bottom of the pyramid’ (BoP) programmes. This article examines how firms manage institutional voids and the consequences of these approaches for workers through a case study of a BoP ‘route to market’ programme designed by a global food manufacturer in Kibera, Africa's largest slum, located in Nairobi. Instead of engaging with Kibera by upgrading informal markets or generating formal employment, the corporation focused on harnessing existing informal systems through composite arrangements of NGOs, social networks and informal enterprises, a strategy the authors term ‘remote (dis)engagement’. The article describes the logics and outcome of this strategy of formal engagement with informal markets, concluding that the BoP business model depends on ‘gig practices’ of flexibility, irregular work and insecurity to realize the much‐heralded ‘fortune at the bottom of the pyramid’.
This article highlights the contribution of randomized, quantitative sampling techniques to answering qualitative questions posed by the study. In short it asks: what qualitative insights do we ...derive from quantitative sampling processes? Rather than simply being a means to an end, I argue the sampling process itself generated data. More specifically, seeking out more than 220 geographically dispersed individuals, selected though a randomized cluster sample, resulted in the identification of relationship patterns, highlighted extant resistance-era hierarchies and patronage networks, as well as necessitated deeper, critical engagement with the sampling framework. While this discussion is focused on the study of former resistance members in Timor-Leste, these methodological insights are broadly relevant to researchers using mixed methods to study former combatants or other networked social movements.
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