Attention is not required to maintain feature bindings in visual working memory

Attention plays an important role in the formation of accurate feature bindings. However, the role of attention in maintaining feature bindings is not as well established. Some research supports the theory that attention is needed to maintain feature bindings in visual working memory (VWM), while other research suggests that bindings remain intact after the withdrawal of attention. Experiment 1 of current study tested this hypothesis by replicating the findings that feature bindings are more difficult to remember than individual features in a whole report change detection task. Experiment 2 directly measured attention through eye tracking and manipulated whether a change occurred to an object within the focus of attention, a previously attended object, or an unattended object. The results of Experiment 2 suggest that attention is not required to maintain feature bindings. Together, the results of the current study suggest that while feature bindings may be more difficult to remember than individual features in some instances, attention is not required to maintain feature bindings in VWM

What you attend to is what you remember : investigating the unit of representation in visual working memory

The unit of representation in visual working memory (VWM) is a matter of some debate. The object benefit occurs when more features are remembered when they are combined into fewer objects. This has been used to support the perspective that objects are the unit of representation in VWM. However, the object benefit occurs only for two features from different dimensions (e.g., a blue circle: color and shape) but not two features from the same dimension (e.g., a red-and-blue bi-colored square: two colors). This suggests that both objects and features may be important in determining VWM capacity. The purpose of this study was to compare the object hypothesis against a new, alternative unit of representation: the Boolean map. A Boolean map is a spatial representation that can also carry information about features, although feature tags must be applied to an entire map. The Boolean map distinguishes between features that must be accessed serially and features that can be accessed in parallel: features that can be accessed in parallel can be represented on the same map, while features that are accessed serially must be represented on different maps. Three experiments were conducted to explore both hypotheses. In Experiment 1, the hypothesis that some types of stimuli are not attended as objects was examined by testing object-based attention for different kinds of objects. In Experiment 2, the Boolean map hypothesis was tested by examining which features can be accessed in parallel and which features must be accessed serially. Finally, in Experiment 3, the object benefit in VWM was tested for the same stimuli used in Experiments 1 and 2. The results showed that even objects that did not show an object benefit in VWM in Experiment 3 were still attended as objects in Experiment 1. However, only features that could be attended in parallel when combined into an object (Experiment 2) showed an object benefit in VWM (Experiment 3). These results suggesting that the unit of representation is restricted by the features that can be accessed in parallel, in support of the Boolean map hypothesis

Co-operation between metastatic tumor cells and macrophages in the degradation of basement membrane (type IV) collagen

AbstractThe co-culture of mouse peritoneal macrophages and Lewis lung carcinoma cells induces the relase of a metal-dependent type IV collagen-degrading proteinase which is not produced in detactable amounts by either cell type cultivated alone. Conditioned media of the co-cultures degrade both pepsin-extracted type IV collagen from human placenta and mouse type IV procollagen. Thus macrophages can interact with tumor cells to degrade basement membrane type IV collagen: this might be of importance to allow cancer invasion and metastasis

Automated goal operationalisation based on interpolation and SAT solving

Goal oriented methods have been successfully employed for eliciting and elaborating software requirements. When goals are assigned to an agent, they have to be operationalised: the agent’s operations have to be refined, by equipping them with appropriate enabling and triggering conditions, so that the goals are fulfilled. Goal operationalisation generally demands a significant effort of the engineer. Although there exist approaches that tackle this problem, they are either in-formal or at most semi automated, requiring the engineer to assist in the process. In this paper, we present an approach for goal operationalisation that automatically computes required preconditions and required triggering conditions for operations, so that the resulting operations establish the goals. The process is iterative, is able to deal with safety goals and particular kinds of liveness goals, and is based on the use of interpolation and SAT solving

Finding and Resolving Security Misusability with Misusability Cases

Although widely used for both security and usability concerns, scenarios used in security design may not necessarily inform the design of usability, and vice- versa. One way of using scenarios to bridge security and usability involves explicitly describing how design deci- sions can lead to users inadvertently exploiting vulnera- bilities to carry out their production tasks. This paper describes how misusability cases, scenarios that describe how design decisions may lead to usability problems sub- sequently leading to system misuse, address this problem. We describe the related work upon which misusability cases are based before presenting the approach, and illus- trating its application using a case study example. Finally, we describe some findings from this approach that further inform the design of usable and secure systems

Annotation management: a Group decision support system for nurses tasks

International audienceWe develop a 5-year empirical investigation that is giving us broad and deep insights to characterise activity management in the palliative ward of an oncology hospital, and offer effective support for group decision-making and collaborative activity of caregivers. Following this observation period, we propose a software prototype based upon annotations in which dealing with patients’ state and evolution is a complex organisational task. We based our conception of an annotation tool on the observations of the rich writing practices of medical professionals. We rely on the innovative strategy of intermediate management to introduce a new technology able to bridge heterogeneous, valuable data flows that addresses both management support and activity support in a single tool

Neural interactions in working memory explain decreased recall precision and similarity-based feature repulsion

Over the last several years, the study of working memory (WM) for simple visual features (e.g., colors, orientations) has been dominated by perspectives that assume items in WM are stored independently of one another. Evidence has revealed, however, systematic biases in WM recall which suggest that items in WM interact during active maintenance. In the present study, we report two experiments that replicate a repulsion bias between metrically similar colors during active storage in WM. We also observed that metrically similar colors were stored with lower resolution than a unique color held actively in mind at the same time. To account for these effects, we report quantitative simulations of two novel neurodynamical models of WM. In both models, the unique behavioral signatures reported here emerge directly from laterally-inhibitory neural interactions that serve to maintain multiple, distinct neural representations throughout the WM delay period. Simulation results show that the full pattern of empirical findings was only obtained with a model that included an elaborated spatial pathway with sequential encoding of memory display items. We discuss implications of our findings for theories of visual working memory more generally

A wide-spectrum approach to modelling and analysis of organisation for machine-assisted decision-making

This paper describes a modeling approach that helps to represent necessary aspects of complex socio-technical systems, such as organization, in an integrated form and provides a simulation technique for analyzing these organisations. An actor-based language is introduced and compared to a conventional simulation approach (Stock-and-Flow) by simulating aspects of a software services company

A formal verification framework and associated tools for enterprise modeling : application to UEML

The aim of this paper is to propose and apply a verification and validation approach to Enterprise Modeling that enables the user to improve the relevance and correctness, the suitability and coherence of a model by using properties specification and formal proof of properties

Human-centered specification exemplars for critical infrastructure environments.

Specification models of critical infrastructure focus on parts of a larger environment. However, to consider the security of critical infrastructure systems, we need approaches for modelling the sum of these parts; these include people and activities, as well as technology. This paper presents human-centered specification exemplars that capture the nuances associated with interactions between people, technology, and critical infrastructure environments. We describe requirements each exemplar needs to satisfy, and present preliminary results in developing and evaluating them