What is the difference between top-down and bottom-up attention?

Attention can be categorized into two distinct functions: bottom-up attention, referring to attentional guidance purely by externally driven factors to stimuli that are salient because of their inherent properties relative to the background; and top-down attention, referring to internal guidance of attention based on …

What is top-down visual attention?

Top-down visual attention improves perception of selected stimuli and that improvement is reflected in the neural activity at many stages throughout the visual system. Recent studies of top-down attention have elaborated on the signatures of its effects within visual cortex and have begun identifying its causal basis.

What is an example of bottom-up attention?

Bottom-up processing takes place as it happens. For example, if you see an image of an individual letter on your screen, your eyes transmit the information to your brain, and your brain puts all of this information together.

Is visual perception top-down or bottom-up?

Gibson (1972) argued that perception is a bottom-up process, which means that sensory information is analyzed in one direction: from simple analysis of raw sensory data to ever increasing complexity of analysis through the visual system.

What can bottom up attention be used for?

The pretrained model generates output features corresponding to salient image regions. These bottom-up attention features can typically be used as a drop-in replacement for CNN features in attention-based image captioning and visual question answering (VQA) models.

How are top down visual attention mechanisms used?

Abstract: Top-down visual attention mechanisms have been used extensively in image captioning and visual question answering (VQA) to enable deeper image understanding through fine-grained analysis and even multiple steps of reasoning.

How is top-down attention used in image captioning?

Bottom-Up and Top-Down Attention for Image Captioning and Visual Question Answering Abstract: Top-down visual attention mechanisms have been used extensively in image captioning and visual question answering (VQA) to enable deeper image understanding through fine-grained analysis and even multiple steps of reasoning.

How are top up and bottom down processes related?

Attention affects the mean neuronal firing rate as well as its variability and correlation across neurons. Although distinct processes mediate the guidance of attention based on bottom-up and top-down factors, a common neural apparatus, the frontoparietal network, is essential in both types of attentional processes.