Study Guide: Schedules of Reinforcement and Motivational Theories

1. Schedule of Reinforcement

  • Definition: A rule specifying which occurrences of a behavior will be reinforced.

  • Continuous reinforcement: Every occurrence of the behavior is reinforced (CRF).

    • Example: Giving a dog a treat every time it sits.

  • Intermittent reinforcement: Only some occurrences are reinforced.

    • Example: Giving a child a sticker only occasionally for cleaning up toys.

2. Four Basic Intermittent Schedules

  1. Fixed-Ratio (FR): Reinforcement after a fixed number of responses.

    • Example: FR-5 → reward every 5 lever presses

    • Response pattern: High rate of responding, brief pause after reinforcement

  2. Variable-Ratio (VR): Reinforcement after a variable number of responses, averaging around a set number.

    • Example: VR-5 → reward after 3 responses, then 7, then 5, etc.

    • Response pattern: High, steady rate; resistant to extinction

  3. Fixed-Interval (FI): Reinforcement for the first response after a fixed amount of time.

    • Example: FI-2 min → first lever press after 2 minutes is reinforced

    • Response pattern: “Scalloped” responding (slow at start of interval, faster as time approaches reinforcement)

  4. Variable-Interval (VI): Reinforcement for the first response after a variable amount of time, averaging around a set time.

    • Example: VI-2 min → first response after 1, then 3, then 2 min, etc.

    • Response pattern: Moderate, steady rate of responding

3. Duration and Noncontingent Schedules

  • Duration schedules: Reinforce performing a behavior continuously for a certain period.

    • DRL (Differential Reinforcement of Low Rate): Reinforce when behavior occurs after a minimum interval

    • DRH (Differential Reinforcement of High Rate): Reinforce when behavior occurs rapidly for a set duration

  • Noncontingent schedules: Reinforcer delivered regardless of behavior.

    • Fixed-Time (FT): Reinforcer delivered after a fixed time, independent of behavior

    • Variable-Time (VT): Reinforcer delivered after variable intervals, independent of behavior

  • Difference from FI/VI: FI/VI depends on behavior; duration/noncontingent schedules may reinforce simply the passage of time or sustained behavior.

4. Response-Rate Schedules

  1. Differential Reinforcement of Low Rate (DRL): Reinforce when responding is below a set rate.

    • Example: Child receives candy if they speak no more than 5 times per hour

  2. Differential Reinforcement of High Rate (DRH): Reinforce when responding is above a set rate.

    • Example: Worker receives bonus if completing at least 10 tasks/hour

  3. Differential Reinforcement of Paced Responding: Reinforce responses within a specific time window.

5. Conjunctive and Adjusting Schedules

  • Conjunctive schedule: Reinforcement occurs only if the subject meets two or more schedule requirements.

    • Example: FR-10 + FI-5 min → must press lever 10 times and wait at least 5 min

  • Adjusting schedule: Requirement changes based on subject’s performance.

    • Example: Rat must press lever faster than its previous rate to earn reinforcement

  • Shaping: Uses an adjusting schedule by gradually increasing performance criteria until target behavior is reached.

6. Chained Schedules

  • Definition: Sequence of two or more simple schedules, each leading to the next, with reinforcement only at the end of the chain.

  • Diagram:

    • Link 1 (FR-5) → Link 2 (VI-2 min) → Reinforcer (food)

  • Difference from Conjunctive schedule: Chained schedules require sequential completion; conjunctive schedules require simultaneous satisfaction.

  • Maintaining behavior in early links: Use conditioned reinforcers (e.g., a tone) for completing each step

  • Best establishment method: Backward chaining (train last link first, then previous links)

  • Goal gradient effect: Response rate increases as animal nears ultimate reinforcement

7. Drive Reduction Theory

  • Definition: Reinforcement occurs when behavior reduces a physiological need (e.g., hunger, thirst).

  • Difficulty: Cannot explain reinforcement for behaviors that do not reduce biological drives, e.g., playing video games.

  • Incentive motivation: Behavior can be motivated by external goals or rewards, not just drive reduction.

8. Premack Principle vs. Response Deprivation Hypothesis

  • Premack Principle: High-probability behavior (HPB) reinforces low-probability behavior (LPB).

    • Example: Practice guitar (HPB) can be used to reinforce practicing piano (LPB)

  • Response Deprivation Hypothesis: Any behavior can serve as reinforcement if access is restricted below baseline.

    • Example: Child practices guitar as reinforcement only if deprived of guitar practice by usual schedule

  • Difference: Premack depends on relative probability; response deprivation depends on restriction below natural baseline

9. Behavioral Bliss Point Approach

  • Definition: Organisms distribute behavior to maximize overall reinforcement across available activities.

  • Example: Child allowed to practice piano for 2 hours before 1 hour of guitar may adjust timing to achieve their preferred balance; bliss point is the natural equilibrium of behavior allocation.