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Modelling object recognition in visual cortex using multiple firing K-means and non-negative sparse coding
Published in Limiao Deng, Cognitive and Neural Modelling for Visual Information Representation and Memorization, 2022
Humans can easily recognize objects despite the tremendous variation in size, position, lighting condition, viewpoint, and other sources of disturbance and noise1. This remarkable ability is mainly supported by the ventral visual stream2 (as shown in Fig. 4.1). The ventral stream starts from the lateral geniculate nucleus (LGN), then goes through the primary visual cortex (V1), and travels through V2 and V4 to the inferior temporal (IT) area3. Neurons in different areas have different properties. For instance, neurons in V1 areas are sensitive to bars, and neurons in V2 areas are sensitive to corners4. While neurons in V4 areas are responsive to boundary information5, IT neurons respond to complicated patterns2 and can directly support invariant object recognition6,7.
Visual Perception
Published in Robert W. Proctor, Van Zandt Trisha, Human Factors in Simple and Complex Systems, 2018
Robert W. Proctor, Van Zandt Trisha
The primary visual cortex is just the first of more than 30 cortical areas involved in the processing of visual information (Frishman, 2001). This information is processed in two streams, called the dorsal (top) and ventral (bottom) streams, which are sometimes called the “where” and “what” streams, respectively. The dorsal stream receives much of its input from the magnocellular pathway and seems to be involved primarily in perception of spatial location and motion and in the control of actions. In contrast, the ventral stream receives both parvocellular and magnocellular input and is important for perception of forms, objects, and colors. Because “what” and “where” are analyzed by distinct systems, we should expect to find situations in which people make “what” and “where” decisions better, depending on which pathway is used.
Impact of Retinal Stimulation on Neuromodulation
Published in Yu Chen, Babak Kateb, Neurophotonics and Brain Mapping, 2017
Output circuitry from the visual cortex to the eye muscles is described as part of either a ventral or a dorsal stream. Signals in those streams are governed by internal awareness, attention, and motivation. As mental priorities shift, signals travel through either the ventral or dorsal stream to the selected target and background. The ventral stream contains information regarding the selected target, and the dorsal stream contains information about the background to provide context for the details of the ventral stream. In effect, the distinction between peripheral and central eyesight—or concepts and details—depends on whether awareness and attention are on internal thoughts or external targets.
Effects of Visual Cues on Distance Perception in Virtual Environments Based on Object Identification and Visually Guided Action
Published in International Journal of Human–Computer Interaction, 2021
Sunyoung Ahn, Sangyeon Kim, Sangwon Lee
Based on the two visual systems, visual cues can be distinguished into two categories (object identification and visually guided action). The ventral stream plays an important role in processing object-specific descriptions such as shape, size, color, lightness, and location (Goodale & Milner, 1992; Lee & Kim, 2008). These factors are not required to visually guide an action (Bridgeman et al., 2000). On the other hand, the dorsal stream is associated with action-relevant information such as orientation, motion, occlusion, shadow, and geometrical surface pattern (Goodale & Milner, 1992; Lee & Kim, 2008). In sum, the ventral stream can be defined as a visual process pathway that deals with object-centered descriptive visual cues required for object identification, whereas the dorsal stream is a visual process pathway that handles viewer-centered descriptive visual cues required for action. Thus, based on the characteristics of each visual system, we categorized visual cues into two for perception and action. In this study, the visual cues for perception and action are manipulated of the combination of several visual cues based on the previous literature: texture, highlights, and color of an object for the VCP; geometrical pattern, shadow distribution, and motion parallax for the VCA manipulation of two visual cues will be described more in detail in the method section.