Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Classical conditioning (Pavlov – 1899, 1927) Pavlov’s original experiments • Pavlov was measuring the amount of saliva produced by dogs when they ate. • He found that the sight or sound of the lab technician feeding the dogs also produced salivation. • Salivation had become associated with a new stimulus (the technician) and not just the original stimulus (food). Key Terms • Classical conditioning – Refers to a form of learning that occurs through the repeated association of two (or more) different stimuli. – Learning is only said to have occurred when a particular stimulus consistently produces a response that it did not previously produce. • Stimulus – Any event that elicits (produces) a response from an organism (eg, food) • Response – A reaction by an organism to a stimulus (eg, salivation) • Conditioned reflex – An automatic response that occurs as the result of previous experience. Unconditioned stimulus (UCS) • Any stimulus which produces an unconditioned response (UCR). – Food (UCS) causes salivation (UCR) Unconditioned response (UCR) • The response which occurs automatically as a result of the unconditioned stimulus (UCS). • A reflexive, or involuntary, response is an UCR as it is predictably caused by an unconditioned stimulus (UCS). – Dogs salivate (UCR) at food (UCS) Conditioned stimulus (CS) • The stimulus which is ‘neutral’ at the start of classical conditioning and does not normally produce the unconditioned response (UCR) but eventually becomes associated with the unconditioned stimulus (UCS). – Sound of bell causes no response – Sound of bell (CS) after being “paired” with food (UCS) produces saliva (UCR) Conditioned response (CR) • The learned or acquired response to the conditioned stimulus. – The sound of the bell (CS) leads to salivation (CR) without the food (UCS) Process of acquisition • The overall process during which the organism learns to associate two events (the CS and the UCS). Stimulus discrimination • The ability to distinguish between two (or more) different stimuli, even if the stimuli are similar. Stimulus generalisation • The tendency for similar stimuli to produce the same, but not necessarily identical, response. Extinction and Recovery • Process of extinction The gradual decrease in the strength or rate of a CR that occurs when the UCS is no longer presented. • Spontaneous recovery: The reappearance of a conditioned response after its apparent extinction. Real-life application • Some animal training such as hand signals or clickers • Aversion therapy – one-trial learning