Psyc 330. Nov. 7 h
Part 1: when does searching require attention?
• Where is Waldo?> accessible way to explain something is easy found and something is hard to
• If something has a unique feature that make it stand out, it will be easy to find that object.
Searching for hardtofind targets
camouflage: less visible to predators
standing out: high visibility clothes at night
Part 2: serial and parallel search
• Visual search experiment ..from 1892
• Neisser’s search task: distractors have similar anglers with “Z” make it difficult to find “Z”
• “Z” has unique feature in angler is easily to be foun▯ pop out!
• Color differences make the target pop out faster than the target has different shape compare to
• Targets without unique features do not pop out
• Conjunction: combination.
• Setsize effect.
it doesn’t matter the number of the distractors for FT and FT absent trial, response time is still
around 400 msecs.
However, when Conjunction & Target absent and CT present (RT is less than the CT absent
trials, because we stop searching when we find the target ▯ serial self terminating search.) trials, the RT
increased along with the increase of the distractors number
Exhaustive search: serial inspection of entire array occurs on target absent trials.
Serial selfterminating search: serial inspection of array terminated when target found
Serials vs. parallel search:
Search for texture boundaries
Part 3: glueing features together▯ potlight
Feature integration theory: we have different spatial maps in our brain and the interaction of different types
of maps determine how easy and how difficult for us to find the target.
Feature maps in color, orientation, and size ▯ master map of locations (parietal cortex, not in visual cortex) ▯
how we find things pop out
serial search: ▯a slow search
illusory conjunctions: support feature integration theory.
noisy mask . 6 2, noisy mask, noisy mask with probe bar
seeing very short of time of the combination of the digits and the geometric shapes.
People only have time to look at the digits.
People need to tell the digits and to identify one of the three geometric shapes.
Error: mismatch the color of one shape with another shape. Never report seen a new color (almost
only three colors).▯ illusory conjunctions.