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The retina has two types of light-sensitive receptor cells (or photoreceptors) called rods and cones. rods: 75 to 150 million cells which are very sensitive to all levels of light. cones: 6 to 7 million cells which are sensitive to color. These cells turn change light into neuronal impulses which travel to the occipital lobe via the optic nerve.
Weber's Law: Ernst Weber noted that for people to perceive a difference between two stimuli, the stimuli must differ by a constant "proportion" rather than a constant amount. Example: Let's say that a person correctly identifies a change in weight between two 20 oz. water bottles when there is a difference of 1 oz. Weber's Law states that in order for a person to notice a change in weight between two 100 oz. bottles the difference would have to be 5 ounces for a person to perceive a change in perception.
Signal Detection Theory: the study of people's tendencies to make correct judgments in detecting the presence of stimuli. -holds that the detection of a stimulus depends on both the intensity of the stimulus and the physical and psychological state of the individual.
Gestalt Psychology The word Gestalt is German and can be translated as 'seeing the whole picture all at once.' Another way to think of this is the phrase 'the whole is more than the sum of its parts.' Gestalt psychologist argue that we don't just see the world, we actively interpret what we see depending on what we are expecting to see. Gestalt Laws of Perceptual Organization Phi Phenomenon: Humans see motion when they view a number of different frames that are strung together like in an animated film. http://en.wikipedia.org/wiki/phi_phenomenon
Law of Similarity
Law of Closure Law of Simplicity
Law of Continuity Illusions are incorrect perceptions. Illusions are created when perceptual cues are distorted so that our brains cannot correctly interpret space, size, and depth cues. Bill Nye illusions watch.webloc
Classical conditioning: A type of learning in which associations are made between a neutral stimulus and a natural stimulus. Discovered by Ivan Pavlov (1849-1936) who was studying the digestive system of dogs. (See classical conditioning handout attached to this file.) Generalization: When the conditioned response is exhibited to a neutral stimulus that is similar to the conditioned stimulus. (Pavlov noticed that the dogs conditioned to drool to circles, also drooled when shown other shapes. Discrimination: When a subject "learns" to distinguish between the conditioned stimulus and similar stimuli. Only the correct conditioned stimulus elicits the conditioned responses. Extinction: When the conditioned stimulus no longer leads to the conditioned response. The effect decays over time.
Operant Conditioning: a form of learning in which a certain action is reinforced or punished, resulting in corresponding increases or decreases in the likelihood that similar actions will occur again. Reinforcement is stronger, but takes longer to learn. Punishment is easier, but is less effective. Dog video. http://www.youtube.com/watch?v=p2bfzuiby9a
B.F. Skinner did a lot of work in this field involving his "Skinner Box". Punishment vs. reinforcement Punishment: When an unpleasant stimulus is added after a behavior and it results in a decrease of the previous behavior. Positive Reinforcement: When a pleasant stimulus is added which increases the likelihood of the previous behavior being repeated. Negative Reinforcement: When an unpleasant stimulus is removed from the environment and it leads to an increase in the previous behavior.
Thorndike's Law of Effect: Responses that are satisfying are more likely to be repeated. Those that are not satisfying are less likely to be repeated. Types of reinforcers: -a Primary Reinforcer is one that satisfies a basic biological need such as hunger, thirst or sleep. -a Secondary Reinforcer is one that has been paired a primary reinforcer and through classical conditioning has acquired value and reinforcement. Examples include money, praise, status, and prestige.
Schedules of Reinforcement: B.F. Skinner discovered by accident (when one of his Skinner boxes broke) that the manner in which reinforcement occurs has a noticeable impact on behavior. He noticed that even though the lever that rats had to depress was broken, the rats continued to press the lever, in some cases, at an even higher rate than before. This lead to further study of reinforcement schedules. Continuous Reinforcement: This occurs when the desired behavior is reinforced EVERY time it occurs. Subjects learn the quickest with this method, but the effect is prone to quick extinction once the reward stops. Partial Reinforcement: This occurs when behaviors are rewarded SOME of the time. Although the schedule of reinforcement can have different effects, Partial Reinforcement takes longer to learn and is more resistant to extinction. 4 Partial -Reinforcement schedules: 1. Fixed Ratio: Reinforce after a set number of behaviors. (Every 4 for example.) Result: Subject works hard, pauses briefly after reward. (Example: piece work.) 2. Variable Ratio: Reinforcement is varied. It may come after 1 or 100 behaviors. The subject never knows. Result: Frequent behaviors at a high and steady rate. (Example: slot machines.)
3. Fixed Interval: Reward the first behavior after a set amount of time. Result: High rate of behavior just prior to reward, and then no behavior right after. In time, the behavior picks up again. (Exam schedule in school.) 4. Variable Interval: Reinforce behavior after varying amounts of time. Result: Slow steady approach to behavior. Factors that Impact Learning Feedback: Finding out the results of an action or performance. Greatly impacts speed and effectiveness of learning. Transfer: When previously learned responses impacts your ability to master a new task. Positive Transfer: Previous learned responses help you to learn a new skill. (Ex: A guitar player learning to play the banjo.) Negative Transfer: Previously learned responses make it more difficult for you to learn a new skill. (Ex: Driving on the left side of the road in other countries.)
Practice: Practicing a skill, helps you to acquire it. Visualization: A form of practice in which you imagine yourself completing the desired task. Research has proven this to be 90% as effective as actual practice. Learning Strategies Learning to learn: Ex: Learning to extract information from a book is more important than the first book you learned to read. Learned Laziness: occurs when a person or subject receives a reward without effort. Learned Helplessness: occurs when a person experiences pain or discomfort regardless of how hard they try.
Learning Complicated Skills Shaping: Process in which reinforcement is use to sculpt new responses out of old ones. Modeling: Showing the subject an example of the desire behavior. (3 effects of modeling) 1. Increases the chances that the subject will exhibit the same behavior. (Ex: Everyone looks up, you look up). 2. Observational learning or imitation. The observer can watch a behavior and then reproduce it closely. Was not able to do this before. (Ex: Learning a new dance.) 3. Disinhibition: Observer watches another subject engage in a "threatening" activity without being punished. Makes them more likely to be able to do it. (Ex: You are more likely to put a snake around your neck if you see a snake handler with one around his neck.)