Sensation

1. Sensation By: Julie Hamilton Psychology Hour 4

2. Table of Contents • What is sensation? • What is bottom-up and top-down processing? • Perception • Absolute and difference threshold, signal detection theory • Sensory adaptation and Selective attention

3. What is sensation? • Sensation is a physical feeling or perception resulting from something that happens to or comes into contact with the body. • An example of sensation would be the smell of roses. Some people may find the smell beautiful while someone else can find the smell nauseating.

4. What is bottom-up and top-down processing? • Bottom-up processing is also known as "small chunk" processing and suggests that we attend to or perceive elements by starting with the smaller, more fine details of that element and then building upward until we have a solid representation of it in our minds. • If you're the type of person who understands concepts and ideas by starting with the details and then working your way up to the main idea of overall concept, then you're a bottom-up processor. • Top-Down Processing is also known as "large chunk" processing and states that we form perceptions (or focus our attention) by starting with the larger concept or idea and then working our way down to the finer details of that concept or idea. • If you're the type of person who learns new ideas and concepts by starting first with the high-level aspects and then working your way down to the fine details, then you're a top-down processor.

5. Perception • Perception is the process in which we understand sensory information. • Illusions are powerful examples of how we misinterpret sensory information and perceive information incorrectly. • Look carefully at the center circles on both the left and right.Which circle is bigger? • Are you sure they aren't both the same size?  This relative size illusion is called the Ebbinghaus illusion.  It was discovered by Hermann Ebbinghaus, a German psychologist, in the early 1900s.

6. How many legs does this elephant have? The impossible elephant was drawn by American cognitive scientist Roger N. Shepard.

7. What do you see below?

8. When you look at the picture in close range who does it look like? And in a further range?

9. Can you pick out the tallest soldier?

10. What do you see?

11. This is a test used to see if a person is color blind. Can you see the letters or numbers hidden in each square? You should see 58 (upper left), 18 (upper right), E (lower left) and 17 (lower right).If you cannot see any of the above numbers/letters, you may suffer from color blindness.

12. Absolute and difference threshold, signal detection theory • Absolute threshold is the smallest detectable level of a stimulus. • Difference threshold is the smallest detectable difference between a starting and secondary level of a particular sensory stimulus. • Perfume tester fit into the category of difference threshold. They are paid high salaries for their sense of smell. • Signal detection theory is the detection of a stimulus depends on both the intensity of the stimulus and the physical and psychological state of the individual. • For example, when you walk to your car that is parked in an empty parking lot late at night all by yourself, you might be much more aware of noises because the situation is somewhat threatening (you are primed and listening carefully to hear anything and everything). In this case, you may hear some slight noises that you might otherwise not hear if you were in a different situation that was not as threatening.

13. Sensory adaptation and selective attention • Sensory adaptation is when we get used to the things around us. • An example would be walking into an unfamiliar place and smelling something after a certain amount of time you get used to it. • Selective attention is purposely focusing your conscious awareness onto a specific stimulus.