Describe the following theories of object recognition

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3.Describe the following theories of object recognition, and explain the advantages and disadvantages of each:Object Recognition- Researchers have proposed many different theories of object recognition.otemplate matching theory– According to one early theory, your visual system compares a stimulus with a set of templates, or specific patterns that you have stored in memory. Then it notes which template matches the stimulus.Advantages– Simple explanationDisadvantagesHowever, every day you manage to recognize letters that differ substantially from the classic version of a letter, especially in handwritten text. oyou can recognize each of those letters, even if you view the letters from a different perspectiveThe template approach fares even worse in recognizing the more complex objects that occupy your visual world. Perception requires a more flexible system than matching a pattern against a specific template ofeature-analysis modelsa visual stimulus is composed of a small number of characteristics or components.Each visual characteristic is called a distinctive featureoEx.how feature-analysis theorists might explain the way that we recognize letters of the alphabet. They argue that we store a list of distinctive features for each letter. the distinctive features for the letter R include a curved component, a vertical line, and a diagonal line. When you look at a new letter, your visual system notes the presence or absence of the various features.It then compares this list with the features stored in memory for each letter of the alphabet. People’s handwriting may differ, but each of their printed R’s will include these three features. oAdvantages – More sophisticated than template matching theorya relatively flexible approachConsistent with the psychological research by Eleanor Gibson as well as Larsen & Bundesen The feature-analysis theories are also compatible with evidence from neuroscience oThe research team of Hubel and Wieselfocused on the primary visual cortex of anesthetized animals oThey presented a simple visual stimulus—such as a vertical bar of light—directly in front of each animal’s eyes.
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oHubel and Wiesel then recorded how a particular neuron in the primary visual cortex responded to that visual stimulus. They continued to test how a variety ofneurons in this region of the cortex responded to visual stimuli. oHubel and Wiesel’s results showed that each neuron responded especially vigorously when the bar was presented to a specific retinal region and when the bar had a particular orientation.oFor example, suppose that a bar of light is presented to a particular location on the animal’s retina. One specific neuron might respond strongly when the bar has a vertical orientation. oAnother neuron, just a hairbreadth away within the visual cortex, might respondmost vigorously when the bar is rotated about 10 degrees from the vertical. oThe visual system contains feature detectors that are present when we are borno

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