Operant Conditioning w12

Operant Conditioning w12

1. The Law of Effect

   • if a behaviour in a given situation leads to satisfying consequences, the behaviour is more likely to be repeated again in that situation; conversely if the behaviour leads to discomfort, it is less likely to be repeated in that situation
     • Edward L. Thorndike conducted research on problem solving in cats by using a “puzzle box” • Time taken for cats to escape from the puzzle box showed an unsteady but gradual decline over trials • This was taken to show evidence of learning – learning the relationships between responses and their consequences
       • latency - how long it took
       • The pattern of responding can be observed through a cumulative graph with each step representing a push of the lever
         • Extinction • The gradual weakening or elimination of a response • Occurs following positive reinforcement when the reinforcing stimulus is no longer presented following the response • Observed in a cumulative recording as a flat line
           • Discriminative stimulus • Are cues, signals, and other stimuli (can be context) that influence behaviour by indicating the probable consequences of a behaviour – Consequences can include reinforcement (as in positive reinforcement) or nonreinforcement (as in extinction) • For example, pressing the bar will only be followed by food pellets when the light is on
             • Stimulus generalisation • Occurs when the responses emitted by the discriminative stimulus are shown to other stimuli • The more similar the stimulus is to the original discriminative stimulus, the more likely generalisation will occur
               • Stimulus discrimination • Occurs when responses emitted by the discriminative stimulus do not occur to other similar stimuli • Typically seen when responses during the discriminative stimulus are reinforced, whereas responses to other stimuli are not
                 • • Remember, for all applications of operant conditioning – You should be able to specify the response, the consequence, and the contingency – Operant conditioning processes may be one of many factors implicated in the situation

2. The basics of operant conditioning

   • B. F. Skinner pioneered research on operant conditioning, using apparatus such as the operant chamber or “skinner box”
   • Operant conditioning is the learning of the association between responses (behaviour) and its consequences – The responses are voluntary – The response are emitted
     • Consequence of behaviour is presentation of a stimulus
       • positive reinforcement - positive punishment
       • Consequence of behaviour is the removal of a stimulus
         • negative reinforcment- negative punishment
   • reinforcment give/add something =positive reinforcement take something away = negative reinforcement
     • Positive reinforcement – An increase in the tendency of a response following the presentation of a stimulus or event
       • Examples from the laboratory • Delivery of seed when a pigeon pecks at a disk tendency to peck at disk increases • Delivery of mild electric current to dopaminergic neurons when a rat depresses a bar  tendency to press bar increases
       • Negative reinforcement – An increase in the tendency of a response following the removal of a stimulus or event – The stimulus or event is typically aversive – Examples from the laboratory • Removal of an electric shock to the floor of the cage when a rat depresses a bar  tendency to press bar increases – Acquisition, shaping, discrimination learning, and generalisation is also shown
         • Positive punishment – A decrease in the tendency of a response following the presentation of a stimulus or event – The stimulus or event is typically aversive – It is not the same as extinction – It is not the same as negative reinforcement (it dosnt remove the prior reinforcement) – Examples from the laboratory • A rat is given a brief electric shock whenever it depresses a bar  tendency to emit the response decreases • A loud noise is presented whenever a pigeon pecks at a disk  tendency to emit the response decreases
           • Negative punishment (removing a pleasant stimulus or event)– A decrease in the tendency of a response following the removal of a stimulus or event – The stimulus or event is typically pleasant or rewarding – It is not extinction or negative reinforcement – Examples from the laboratory • Removal of stimulation to dopaminergic neurons following a response – Like positive punishment, it can show discrimination learning and generalisation
             • The salience of reinforcers and punishers depend on
               • Situational and organismic factors • Food reinforcement will only be effective if the animal is hungry • Sending a child to his or her room will not be punishment if the room contains many reinforcing stimuli (e.g., TV, computer games, toys, books)
               • Timing • A delay between a response and the consequence the slower the learning. timing is vital consequence immediate the greater the interval in between the response consequence the less likely it is to hold
             • different types of reinforcers and punishers
               • Primary reinforcers/punishers act through inherent biological needs • Food satisfies hunger • Electric shock causes pain • Solitary confinement produces social isolation
                 • Secondary (or Conditioned) reinforcers/punishers acquire reinforcing qualities through a prior association with primary reinforcers • Jewellery • Luxury cars • Prestigious job. reinforced by associated with primary