Riesenhuber & Poggio recently proposed a model of object recognition in cortex which, beyond integrating general beliefs about the visual system in a quantitative framework, made testable predictions about visual processing. In particular, they showed that invariant object representation could be obtained with a selective pooling mechanism over properly chosen afferents through a MAX operation:...

Application of 3D data derived from images captured using unmanned aerial vehicles (UAVs) in forest biomass estimation has shown great potential in reducing costs and improving the estimates. However, such data have never been tested in miombo woodlands. UAV-based biomass estimation relies on the availability of reliable digital terrain models (DTMs). The main objective of this study was to eva...

OBJECTIVES To compare muscle power between youth who acquired HIV perinatally and HIV unexposed uninfected (HUU) youth. METHODS We assessed muscle power (relative to body mass, Pmax/mass), muscle force normalized to body weight (Fmax/BW), force efficiency, jump height (Hmax) and velocity (Vmax) during a single two-legged jump with hands on waist on a force platform (Leonardo) in HIV+ youth (n...

MIIND (Multiple Interacting Instantiations of Neural Dynamics) is a highly modular multi-level C++ framework, that aims to shorten the development time for models in Cognitive Neuroscience (CNS). It offers reusable code modules (libraries of classes and functions) aimed at solving problems that occur repeatedly in modelling, but tries not to impose a specific modelling philosophy or methodology...

To isolate the neural mechanisms associated with recognizing objects from those processing basic visual properties, control stimuli are required that contain the same perceptual properties as the objects but are unrecognizable. We demonstrate that conventional methods for generating control stimuli (phase scrambling, box scrambling, texture scrambling) yield poor controls because they dramatica...

Biologically inspired, from the early HMAX model to Spatial Pyramid Matching, pooling has played an important role in visual recognition pipelines. Spatial pooling, by grouping of local codes, equips these methods with a certain degree of robustness to translation and deformation yet preserving important spatial information. Despite the predominance of this approach in current recognition syste...

A a ST RA C T Individual , isolated rhabdoms from dark-adapted crayfish (Orconectes, Procambarus) were studied with a laterally incident microbeam that could be placed in single stacks o f microvilli. Concentrat ion gradients of metarhodopsin along the lengths of microvilli were produced by local bleaches, accomplished by irradiat ion with small spots of orange light at pH 9 in the presence of ...

We determined the degree to which the response modulation of macaque inferior temporal (IT) neurons corresponds to perceptual versus physical shape similarities. IT neurons were tested with four groups of shapes. One group consisted of variations of simple, symmetrical (i.e. regular) shapes that differed in nonaccidental properties (NAPs, i.e. viewpoint-invariant), such as curved versus straigh...

Nonaccidental properties (NAPs) are image properties that are invariant over orientation in depth and are distinguished from metric properties (MPs) that can change continuously with variations over depth orientation. To a large extent NAPs allow facile recognition of objects at novel viewpoints. Two match-to-sample experiments with 2D or 3D appearing geons assessed sensitivity to NAP vs. MP di...

The computational processes underlying object categorization in cortex are still poorly understood. In a recent experiment, Freedman et al. recorded from inferotemporal (IT) and prefrontal cortices (PFC) of monkeys performing a “cat/dog” categorization task ([1] and Freedman, Riesenhuber, Poggio, Miller, Soc. Neurosci. Abs.). In this paper we analyze the tuning properties of view-tuned units in...