title: A single mechanism can explain the speed tuning properties of MT and V1 complex neurons

authors: Perrone, John A.

subjects: speed tuning

abstract: A recent study by Priebe et al., (2006) has shown that a small proportion (27%) of primate directionally selective, complex V1 neurons are tuned for the speed of image motion. In this study, I show that the weighted intersection mechanism (WIM) model, which was previously proposed to explain speed tuning in middle temporal neurons, can also explain the tuning found in complex V1 neurons. With the addition of a contrast gain mechanism, this model is able to replicate the effects of contrast on V1 speed tuning, a phenomenon that was recently discovered by Priebe et al., (2006). The WIM model simulations also indicate that V1 neuron spatiotemporal frequency response maps may be asymmetrical in shape and hence poorly characterized by the symmetrical two-dimensional Gaussian fitting function used by Priebe et al., (2006) to classify their cells. Therefore, the actual proportion of speed tuning among directional complex V1 cells may be higher than the 27% estimate suggested by these authors.

text: A single mechanism can explain the speed tuning properties of MT and V1 complex neurons A recent study by Priebe et al., (2006) has shown that a small proportion (27%) of primate directionally selective, complex V1 neurons are tuned for the speed of image motion. In this study, I show that the weighted intersection mechanism (WIM) model, which was previously proposed to explain speed tuning in middle temporal neurons, can also explain the tuning found in complex V1 neurons. With the addition of a contrast gain mechanism, this model is able to replicate the effects of contrast on V1 speed tuning, a phenomenon that was recently discovered by Priebe et al., (2006). The WIM model simulations also indicate that V1 neuron spatiotemporal frequency response maps may be asymmetrical in shape and hence poorly characterized by the symmetrical two-dimensional Gaussian fitting function used by Priebe et al., (2006) to classify their cells. Therefore, the actual proportion of speed tuning among directional complex V1 cells may be higher than the 27% estimate suggested by these authors.

year: 2006

title: Local economic impact modelling: TIEBOUT, tourism and training

authors: Chalmers, Lex

abstract: This paper describes the use of a sophisticated computer model in university teaching. TIEBOUT is a PC‐based program which assesses the economic impacts of expenditure in National Parks. The program has been used extensively by Parks Canada, but it has had even greater use as a teaching tool at the University of Waterloo. The paper documents the development, features and use of the TIEBOUT model, and then outlines the way students were asked to conceptualise, execute and comment on various scenarios using the model. The real world basis of the model, and the elegance of its formulation, allowed some fundamental concepts in the operation of multipliers to be fully explored. The final section of the paper reports on student and instructor evaluations of the TIEBOUT teaching program.

text: Local economic impact modelling: TIEBOUT, tourism and training This paper describes the use of a sophisticated computer model in university teaching. TIEBOUT is a PC‐based program which assesses the economic impacts of expenditure in National Parks. The program has been used extensively by Parks Canada, but it has had even greater use as a teaching tool at the University of Waterloo. The paper documents the development, features and use of the TIEBOUT model, and then outlines the way students were asked to conceptualise, execute and comment on various scenarios using the model. The real world basis of the model, and the elegance of its formulation, allowed some fundamental concepts in the operation of multipliers to be fully explored. The final section of the paper reports on student and instructor evaluations of the TIEBOUT teaching program.

year: 1992

title: Te Pūtahitanga: A Tiriti-led science-policy approach for Aotearoa New Zealand

authors: Kukutai, Tahu

abstract: This paper examines the interface between science and policymaking and calls for a policy approach that is enabled by, and responsive to, Te Tiriti o Waitangi and Mātauranga Māori. For a science sector to have its greatest reach and impact for all citizens, it must demonstrate relevance, accessibility and inclusion. In Aotearoa, there has been concern about the exclusion of Māori and Pacific expertise from science advice and key decision-making roles. Te Tiriti offers a powerful framework for connecting systems and communities of knowledge in ways that are mutually beneficial and future focused.

text: Te Pūtahitanga: A Tiriti-led science-policy approach for Aotearoa New Zealand This paper examines the interface between science and policymaking and calls for a policy approach that is enabled by, and responsive to, Te Tiriti o Waitangi and Mātauranga Māori. For a science sector to have its greatest reach and impact for all citizens, it must demonstrate relevance, accessibility and inclusion. In Aotearoa, there has been concern about the exclusion of Māori and Pacific expertise from science advice and key decision-making roles. Te Tiriti offers a powerful framework for connecting systems and communities of knowledge in ways that are mutually beneficial and future focused.

year: 2021-04-28