PS352 Psychology Of Learning - Flashcards

Neural Basis of Learning

• Professor: Sean Commins (Sean.Commins@mu.ie, SF20 John Hume Building)
• Weeks 1-2 covered by Prof. Commins
• Weeks 3-10 covered by Prof. Bryan Roche (The Behavioural Approach to Learning)

Course Topics

• Learning in invertebrates:
  • Habituation
  • Sensitization
  • Classical conditioning
• Learning in vertebrates: Long-Term Potentiation (LTP)
• Re-visiting place cells and the neural code.
• The Behavioural Approach to Learning
• Habituation, sensitisation and classical conditioning
• Reinforcement, extinction, inhibition & aversive control
• Operants, Shaping & Schedules
• The Discriminated Operant & Stimulus Equivalence
• Relational Frame Theory

Reading Material

• Commins, S. (2018). Behavioural Neuroscience. CUP. (Chapters 5, 6, 7, and 14)
• Jeffery, K. (2003). The Neurobiology of Spatial Behaviour. Oxford University Press.
• All slides and extra reading material will be on Moodle

Non-Associative Learning

• Definition: Change in behavioral response over time to a single type of stimulus.
• Types:
  1. Habituation
  2. Sensitization

1. Habituation

• Example: Getting used to the ringing of a telephone.
• Definition: A form of learning in which a response to a stimulus weakens with repeated presentation.

2. Sensitization

• Example: Walking on a street and becoming jumpy after a blackout.
• Definition: Increase of a response due to the presentation of a novel, often noxious stimulus.

Associative Learning

• Definition: Associations are formed between events.
• Types:
  1. Classical Conditioning
  2. Instrumental Learning
• Example: Associating a telephone number with a person.

1. Classical Conditioning

• Described by Pavlov.
• Involves associating a stimulus that evokes a measurable response with a second stimulus that normally doesn’t evoke this response.
• Example: Bell and meat (Pavlov's dog experiment).

Pavlov's Experiment

• Before conditioning:
  • Food (UCS) -> Salivation (UCR)
  • Bell -> No Response
• During conditioning:
  • Bell + Food (UCS) -> Salivation (UCR)
• After conditioning:
  • Bell (CS) -> Salivation (CR)
• Timing is critical:
  • Conditioning occurs if the US (Bell) and CS (Meat) are presented simultaneously or if the CS (Bell) precedes the US (Meat) by a very short interval.
  • If the interval lengthens, the effect may disappear.

2. Instrumental Learning

• Developed by Thorndike.
• Learning to associate a response with a meaningful stimulus, such as a reward or punishment.
• Example: Exams.

Learning in Invertebrates

• Why study invertebrates?
  • Small nervous system.
  • Large neurons.
  • Simple genetic make-up.

Aplysia (Sea Slug)

• Used as a model organism.
• Siphon expels waste and helps the animal to move.
• Gill is used for breathing.

Habituation in Aplysia

• If you lightly touch the tail of the Aplysia, it immediately draws its tail away from you.
• If you continue to touch the tail in the same spot, the Aplysia will stop contracting its tail.
• It has habituated to the touch.
• If you continue to squirt water, the gill stops withdrawing.

Neural Level of Habituation

• Behavioral change must be reflected at the neural level.
• Sensory neuron and motor neuron involvement.
• Action potentials do not diminish as stimulation continues at the input stage (sensory neuron).
• Contractions do not diminish as stimulation continues at the output stage (motor neuron).
• Habituation takes place at the sensory/motor neuron junction.

Molecular Level of Habituation

• Ca^{++} (Calcium) involvement.
• Glutamate neurotransmitter.
• Initially, a strong gill withdrawal response is produced.
• With time and habituation, less Ca^{++} channels open.
• Less Ca^{++} influx.
• Less neurotransmitter released.
• Less depolarization.
• This produces a weaker gill withdrawal response.
• The animal has learned and habituated.

Summary

• A simple model of learning (habituation) that can be understood not just at the behavioral level, but also at cellular and molecular levels.