Preparation video for Psychobiology Workshop and Analysing Data

Introduction

• Overview of the purpose of the video:

  • Preparation for Analysing Data Takeaway Paper and Psychobiology Workshop.

  • Focus on understanding the experiment conducted with computerized rats and its analysis.

• Importance of learning concepts in the experimental context.

Background Information on Learning

• Types of Learning:

  • Humans and animals learn facts and associations in their environment.

  • Associative Learning: Learning associations between stimuli and events.

Types of Associative Learning

• Classical Conditioning:

  • Also known as Pavlovian conditioning.

  • Passive learning about associations (e.g., Pavlov's dogs associating bell with food).

• Operant Conditioning:

  • Named after B.F. Skinner.

  • Active learning where actions lead to consequences (also called instrumental conditioning).

  • Focus on behavior shaping by its outcomes.

Operant Conditioning Experiment

• Skinner Box:

  • A controlled environment for studying behavior; contains a lever and food cup.

  • Rats learn to associate lever pressing with sugar delivery.

Mechanisms of Reinforcement

• Positive Reinforcement:

  • Behavior is more likely to occur due to positive outcomes, like receiving food (sugar).

• Negative Reinforcement:

  • Behavior is more likely to occur to avoid negative outcomes, such as foot shocks or unpleasant sounds.

• Thorndike's Laws:

  • Law of Effect: Behaviors leading to positive outcomes are likely to recur.

  • Frequencies of behaviors strengthen these learned associations.

Consequences of Behavior

• Consequences:

  • Can either reinforce (increase likelihood) or deter (reduce likelihood) behavior.

• Reinforcement Types:

  • Positive outcomes (e.g., sugar) and negative outcomes (e.g., avoiding shocks) both reinforce behavior.

Reinforcement Schedules

• Definition: Rules dictating how often and when reinforcement occurs.

• Different Schedules:

  • Ratio Schedules:

    • Reinforcement based on number of responses.

    • Fixed Ratio (FR): A consistent number of responses (e.g., FR-6).

    • Variable Ratio (VR): Average number of responses varies (e.g., VR-6).

  • Interval Schedules:

    • Reinforcement based on the time elapsed.

    • Fixed Interval (FI): Same time must pass (e.g., FI-8 seconds).

    • Variable Interval (VI): Average time varies (e.g., VI-8 seconds).

• Effects on Behavior:

  • Higher rates of responses observed under ratio schedules compared to interval schedules.

Hypothesis in Current Experiment

• Objective: Explore whether ratio training is more effective in terms of cost-benefit (more pressing, less food).

• Hypothesis: Training under ratio schedules leads to more lever presses but fewer food rewards compared to interval training.

Experimental Design

• Use of Virtual Rats (Sniffy):

  • Sniffy represents a virtual rat in an operant conditioning scenario.

  • Motivation: Sniffy is consistently hungry.

• Procedure:

  • Four groups of ten virtual rats trained under different schedules after initial continuous reinforcement phase.

    • Schedules: Fixed Ratio 6, Variable Ratio 6, Fixed Interval 8, Variable Interval 8.

  • Dependent Variables: Number of lever presses and food rewards over a 10-minute timeframe.

• Data Collection: Monitored rat behavior to gather data for analysis in take-home assignments.

Visual Aid

• View Sniffy's behavior under the different schedules in provided video, "Sniffy in the Experiment."