Classical Conditioning (aka Pavlovian Conditioning)

n  Associations / Pairings

n  Terminology

n  Measures/ Types of Trials

n  Related Concepts

Learning via Association

n  Learning in Classical Conditioning is by association

n  Key: Pair two stimuli together—one has some important survival characteristic, one does not n Learned stimulus must occur before presentation of

the stimulus that elicits (causes) the reaction n Through pairing, the once-neutral stimulus (NS)

becomes a conditioned stimulus (CS)

Learning via Association cont.

n  CS à CR chain is a learned (or conditioned) reflex n most stimuli are external

n  Important questions to ask in Classical Conditioning: n What was learned (conditioned)? n What was innate (unlearned, unconditioned)? n Which is the stimulus? n Which is the response?

Pavlov’s Procedure

n  Food (US) paired (associated) w/ Metronome (NS)

n  Result: NS became CS (conditioned stimulus)

Classical Conditioning

Before Conditioning:

NS

US

reflex

UR

NS = Neutral Stimulus US = Unconditioned Stimulus UR = Unconditioned Response

•  Food (US) paired (associated) w/ Bell (NS) •  Result: NS became CS (conditioned stimulus)

Classical Conditioning After Conditioning:

conditioned reflex

CS

CR

CS = Conditioned Stimulus CR = Conditioned Response

Pavlov’s Procedure

n  How do we know this change occurred? n Saliva flowed during presentation of just the CS,

before the US (food) was presented

Terminology in Classical Conditioning

n  “Learned” = “Conditioned” n  “Unlearned” = “Unconditioned” n  US (Unconditioned Stimulus) n  UR (Unconditioned Response) n  CS (Conditioned Stimulus) n  CR (Conditioned Response) n  Learned / Conditioned Reflex n  Association / Pairing

Measures in Classical Conditioning

n  Percentage of CRs: % of trials in which CR occurred

n  Magnitude of CR: (e.g. amount of saliva produced)

n Percentage and Magnitude of CR should both increase with successive trials

n  Latency of CR: time between onsets of CS & CR n Latency typically decreases with successive trials

n  Direct physiological response n Changes in HR, BP, muscular tension

Measures in Classical Conditioning cont.

n  Indirect measurements n Approach to/Avoidance of CS

Two Types of Trials

n  Conditioning Trials (Training Trials, Regular Trials): trials in which there is a CS-US pairing

n  Test Trial: trials in which the CS is presented alone

n Usually interspersed among Conditioning trials

n Typically present ~1 Test trial among every 10 Conditioning trials or so

Related concepts n  Extinction: CS repeatedly presented w/o US

n  Ring bell: no food -> little or no salivation n  Crying ‘wolf’

Disinhibition n  Recovery of CR during extinction after novel stimulus n  Like dishabituation, but for CR inhibited by extinction

Spontaneous Recovery n  Reappearance of CR after time passes after extinction n  Running into your ex, those feelings return (briefly)