Learning (Lecture 3)

1. Learning (Lecture 3) The goal: Survival in face of unknown challenges The tools: a. Adaptation of society across generations by genetic change. b. Adjustment of individuals by exploitation of the genetic endowment: Unconditioned behaviors. Conditioned (learned) behaviors.

2. Perspectives on learning Behaviorist: Simple associations between events and behaviors are the building blocks of complex learning. Cognitive: Flow of information…knowledge. Biological: Brain plasticity, synaptic strength. Ethological: Species specific learning constrained by genetic endowment. 21/11/05

3. Explanation in psychology • Finding: Learning. • Explanation: Psychological generalization: Hypothetical structure explains the learning process (predictive value of CS…). Biological reductionism: Biological structure explains the learning process (synaptic plasticity).

4. Behavior Neurons level Systems level Biological reductionism Sub-Neuronal level Neurons Computational models at all levels

5. Measuring behavior: then and now Thorndike’s Puzzle Boxes Modern technology

7. Classical conditioning (1)

8. Classical conditioning (2) • Unconditioned behavior: US-UR Reflex arc Tabula rasa? (Locke) • Conditioned behavior: CS-CR • Association-contingency: CS-US time & space • UR - CR: motor & emotional • 2nd order conditioning: CS serves as US Contingency = מקרה

9. Classical conditioning (3) • Temporal CS-US contiguity ? Contiguity is not enough ! • Contingency - cognitive predictability of US by CS. • Biological up and down modulation of synaptic strength. Contiguity = סמיכות Classical conditioning in aplysia: Prediction of future in aplysia ?

11. Classical conditioning (4) Clinical examples: Anticipatory nausea in chemotherapy Placebo effects Craving for drugs Panic attacks Phobic responses Motor balance restoring reflexes

12. From classical to operant conditioning

13. Operant learning (1) Active organism Simple trial-and-error Learning: behavioral operation on the environment & feedback from the environment Law of effect: selection of responses that are followed by positive feedback.

14. Research strategy - World degraded to absurdum

15. Shaping of creativity? Is it possible?

16. Operant learning (2) Feedback from the environment: Reinforcement: behavior up + reinforcement: after the response - reinforcement: terminated by response Punishment: behavior down

18. Operant learning (3) Clinical examples: Patient adherence Frequent attending Drug dependence Token economics

19. Complex Learning Cognitive perspective: Acquisition of mental representations of the world. Thought as a simulation of the reality. Operate on mental representations (VR?).

20. From behaviorism to cognitive sciences Tolman’s cognitive map Mental representation of the space and not a sequence of left-right turns

22. Neuroscience perspective (1) Most learning laws are based on Hebb’s rule dated 1949: if two neurons are simultaneously active, then …. the connection between them gets stronger Learning = plasticity of Hebbian synapse

23. Neuroscience perspective (2)

24. END