Image classification and cognition using contour curvature statistics

Although the higher order mechanisms behind object representation and classification in the visual system are still not well understood, there are hints that simple shape primitives such as “curviness” might activate neural activation and guide this process. Drawing on elementary invariance principles, we propose that a statistical geometric object, the probability distribution of the normalized contour curvatures (NCC) in the intensity field of a planar image, has the potential to represent and classify categories of objects. We show that NCC is sufficient for discriminating between cognitive categories such as animacy, size and type, and demonstrate the robustness of this metric to variation in illumination and viewpoint, consistent with neurobiological constraints and psychological experiments. A generative model for producing artificial images with the observed NCC distributions highlights the key features that our metric captures and just as importantly, those that it does not. More broadly, our study points to the need for statistical geometric approaches to cognition that build in both the statistics and the natural invariances of the sensory world.

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Lying and Neuroscience

The Oxford Handbook of Lying ◽

10.1093/oxfordhb/9780198736578.013.35 ◽

2018 ◽

pp. 455-468

Author(s):

Giorgio Ganis

Keyword(s):

Cognitive Neuroscience ◽

Deception Detection ◽

General Purpose ◽

Neural Activation ◽

Potential Applications ◽

Key Features ◽

Theoretical Question

This chapter provides an overview of the literature on the cognitive neuroscience of deception and deception-detection. First, the two main classes of deception paradigms are briefly introduced and some of their key features are discussed. Next, key results of electrophysiological and neuroimaging studies are summarized and the main findings reviewed, in terms of both theoretical implications and potential applications. The key theoretical question about whether the patterns of neural activation found in these neuroimaging studies reflect deception-specific processes or, conversely, general-purpose processes, is discussed in detail within the context of reverse inferences in cognitive neuroscience.

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Interpretation of the Filament Depression at Millimetric and Centimetric Wavelengths

International Astronomical Union Colloquium ◽

10.1017/s0252921100065349 ◽

1979 ◽

Vol 44 ◽

pp. 131-134

Author(s):

A. Raoult ◽

P. Lantos ◽

E. Fürst

Keyword(s):

Radio Telescope ◽

Active Regions ◽

Simple Shape ◽

Quiet Sun ◽

Unstable Process

The depressions at centimetric and millimetric wavelengths associated with the filaments are studied using already published maps as well as unpublished observations from the Effelsberg 100 m radio telescope of the M.P.I., Bonn. The study has been restricted to large Ha quiescent prominences of relatively simple shape, situated far from the limb and from active regions. The data has been reduced employing one method whose main characteristics are choice of a local quiet sun definition and avoidance of the unstable process of deconvolution.

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An experimental comparison of viewpoint-specific and viewpoint-independent models of object representation

The Quarterly Journal of Experimental Psychology Section A ◽

10.1080/027249800410553 ◽

2000 ◽

Vol 53 (3) ◽

pp. 792-824 ◽

Cited By ~ 1

Author(s):

Michael B. Johnston ◽

Anthony Hayes

Keyword(s):

Object Representation ◽

Experimental Comparison

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Do Writing Directions Influence How People Map Space onto Time?

Swiss Journal of Psychology ◽

10.1024/1421-0185/a000215 ◽

2018 ◽

Vol 77 (4) ◽

pp. 173-184

Author(s):

Wenxing Yang ◽

Ying Sun

Keyword(s):

Mental Representations ◽

Space Time ◽

Horizontal Axis ◽

Causal Role ◽

Writing Systems ◽

Temporal Cognition ◽

Japanese Speakers ◽

Psychological Experiments ◽

Vertical Up

Abstract. The causal role of a unidirectional orthography in shaping speakers’ mental representations of time seems to be well established by many psychological experiments. However, the question of whether bidirectional writing systems in some languages can also produce such an impact on temporal cognition remains unresolved. To address this issue, the present study focused on Japanese and Taiwanese, both of which have a similar mix of texts written horizontally from left to right (HLR) and vertically from top to bottom (VTB). Two experiments were performed which recruited Japanese and Taiwanese speakers as participants. Experiment 1 used an explicit temporal arrangement design, and Experiment 2 measured implicit space-time associations in participants along the horizontal (left/right) and the vertical (up/down) axis. Converging evidence gathered from the two experiments demonstrate that neither Japanese speakers nor Taiwanese speakers aligned their vertical representations of time with the VTB writing orientation. Along the horizontal axis, only Japanese speakers encoded elapsing time into a left-to-right linear layout, which was commensurate with the HLR writing direction. Therefore, two distinct writing orientations of a language could not bring about two coexisting mental time lines. Possible theoretical implications underlying the findings are discussed.

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