Operant Conditioning

• Operant conditioning


  A type of learning whereby the consequence of a behaviour determines the likelihood that it will be performed in the future
• Operant conditioning proposes that someone will tend to repeat a behaviour that has a desirable consequence or that will enable it to avoid undesirable consequences
• Positive consequences strengthen the behaviour and make it likely to recur and negative consequences weaken the behaviour and make it less likely to recur
• Three-Phase Model of Operant Conditioning

  1. Antecedent (A): a stimulus that occurs before the behaviour

  2. The Behaviour (B): that occurs due to the antecedent

  3. The Consequence (C) of the behaviour
• The three-way relationship between these elements and the order in which they occur is called the three-phase model of operant conditioning
• The antecedent (A) must be present for the relevant behaviour to occur
• The behaviour is the voluntary action that occurs in the presence of an antecedent stimulus- in all cases, it has an effect on the environment in the form of the consequence that follows it
• The consequence is the environmental event that occurs immediately after the behaviour and has an effect on the occurrence of the behaviour (if it is positive or negative)
• Reinforcement


  A process in which a stimulus strengthens or increases the frequency or likelihood of a response that it follows
• Reinforcer


  Any stimulus (reward) that strengthens or increases the frequency/likelihood of a response/behaviour that follows it
• Positive reinforcement


  The adding of a desirable consequence following a response, which strengthens behaviour because it adds a pleasant/desirable experience
• Negative reinforcement


  The removal of an unpleasant stimulus following a response, which strengthens behaviour because it stops or removes an unpleasant experience
• Schedule of Reinforcement

  A program for giving reinforcement: specifically the frequency and manner in which the desired response is reinforced
• Types of Reinforcement Schedules

  • Continuous schedules
  • Partial schedules (intermittent schedules)
• Continuous Schedule

  Every instance of a desired behaviour is reinforced
• Partial Schedule

  The desired behaviour is only reinforced occasionally
• Types of Partial Reinforcement Schedules

  • Fixed-ratio
  • Fixed-interval
  • Variable-ratio
  • Variable-interval
• Continuous Reinforcement

  1. Reinforcement is provided every single time after the desired behaviour

  2. Association is easy to make and learning occurs quickly

  3. Extinction occurs quickly after reinforcement is no longer provided
• Example of Continuous Reinforcement

  • Candy machines - every time we put money in (behaviour), we receive candy in return (positive reinforcement)
• Partial (Intermittent) Reinforcement Schedules

  • Only reinforce the desired behaviour occasionally rather than all the time
  • Leads to slower learning but produces behaviour more resistant to extinction
• Fixed Schedule

  The number of responses or amount of time between reinforcements is set and unchanging
• Variable Schedule

  The number of responses or amount of time between reinforcements changes randomly
• Ratio Schedule


  Reinforcement occurs after a certain number of responses have been emitted
• Interval Schedule


  Reinforcing a behaviour after a period of time has passed
• Ratio schedules


  Produce higher response rates compared to interval schedules
• Variable schedules


  Produce more consistent behavior than fixed schedules
• Unpredictability of reinforcement


  Results in more consistent responses than predictable reinforcement
• Resistance to extinction


  Schedules that reinforce unpredictably are more resistant to extinction
• Variable-ratio schedule


  More resistant to extinction than the fixed-ratio schedule
• Variable-interval schedule


  More resistant to extinction than the fixed-interval schedule as long as the average intervals are similar
• Fixed-ratio schedule

  Resistance to extinction increases as the ratio increases
• Fixed - interval schedule

  Resistance to extinction increases as the interval lengthens in time
• Out of the four types of partial reinforcement schedules, the variable-ratio is the schedule most resistant to extinction
• This can help to explain addiction to gambling - even as gamblers may not receive reinforcers after a high number of responses, they remain hopeful that they will be reinforced soon