BCS 111 Chapter 5: Textbook Reading 5

• School: University of Rochester
• Department: Brain and Cognitive Sciences
• Course: BCS 111
• Professor: Yang

Document Summary

The context in which a pattern or object appears apparently sets up certain expectations in the perceiver as to what objects will occur. Accuracy and the length of time needed to recognize objects vary with the context. For example, people recognize objects such as food and utensils faster in a scene depicting a kitchen than they do in the same scene jumbled up. Top-down processes are those directed by expectations derived from context, past learning, or both. Top-down processes need to interact with bottom-up processes. David marr proposed that perception proceeds in terms of several different, special-purpose computational mechanisms such as a module to analyze color, another to analyze motion, etc. Each mechanism operates autonomously without regard to the input from or output to any other module and without regard to real-world knowledge. Marr believed that visual perception proceeds by constructing three different mental representations, or sketches.