PSYC 356 Lecture Notes - Lecture 5: Panic Attack, Habituation, Classical Conditioning
Excitatory Classical Conditioning:
● The organism learns association between the CS (conditioned stimulus) and US
(unconditioned stimulus) and can anticipate the presence of the US
○ CS +
○ Bell= CS + — this predicts food in the example of Pavlov’s dog
● Classical conditioning is affected by CS-US timing
● Terminology
○ Conditioning Trial: single trial w/ 1 US and 1 CS
○ Training Session: a series of conditioning trials
○ Intertrial interval: the end of 1 trial to the start of the start of the next
○ Interstimulus Interval: time from start of CS to the start of the US
[Side 14]
● CR assessed by presenting the CS alone
● What is the CS? CR?
● Quantifying the CR:
○ Magnitude— How much?
○ Probability— Likelihood?
○ Latency— When?
“Control’ Complications:
● Habituation
○ Was there prior exposure?
● Pseudoconditioning
○ Is a change in CR due to sensitization?
Example: Repeated meat powder sensitizes drooling
Controls in Classical Conditioning:
● Random Control: GOOD
○ CS and US occur randomly in same trial
○ Can still produce learning
● Explicitly Unpaired Control: BEST
○ US and CS presented on different trials
○ Far apart to prevent associations
○ How far depends upon the system
■ Example: Eyeblink vs Taste Aversion
Which conditions produce the strongest learning?
● Interstimulus Interval- key is time from CS onset to US onset
● Conditioning is optimal when CS predicts the US will occur soon
○ Best: short delay
○ Worst: simultaneous
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● BUT modern theories indicate all procedures produce strong learning, it’s just not
displayed
● Temporal Coding Hypothesis:
○ The organism learns not only the CS-US association, but when it occurs
Inhibitory Classical Conditioning: The organism learns associations between the CS and US
and thus can predict the absence of a US
CS-
● Unpredictable aversive stimuli are highly detrimental
● We seek periods of low risk
● We are built to predict the absence of an event:
○ Likelihood of no pain
○ Likelihood of no pleasure
● Prerequisite for Inhibitory Conditioning: for the absence of the US to be a significant
stimulus for learning, the US must occur periodically
○ Example: Sunny day (no rain), it must occasionally rain
● Two basic procedures for Inhibitory conditioning
○ Standard procedure
○ Negative contingency
● Two trials randomly alternated:
○ Trial Type A- CS+ (Tone) paired with US (Shock)
○ Trial Type B- CS+ (Tone) and CS- (Light), no US
● In Inhibitory Trial B:
○ CS+: Tone
○ CS-: Light
○ Light (CS-) will come to signal safety
Inhibitory Conditioning- Negative Contingency
● In the trial:
○ US: presented periodically
○ CS-: occurrence of CS- followed by absence of US
○ No explicit CS+
● It is and inhibitory trial:
○ The implicit CS+ is the context
○ CS- becomes negatively correlated with the US (i.e. safety)
○ Example: A child is bullied (US) only when a teacher (CS-) is not in the room
(implicits CS+)
How do we measure the CS-?
Summation Test: Identifies a stimulus as a CS- if it reduces responding elicited by CS+
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
The organism learns association between the cs (conditioned stimulus) and us (unconditioned stimulus) and can anticipate the presence of the us. Bell= cs + this predicts food in the example of pavlov"s dog. Classical conditioning is affected by cs-us timing. Conditioning trial: single trial w/ 1 us and 1 cs. Training session: a series of conditioning trials. Intertrial interval: the end of 1 trial to the start of the start of the next. Interstimulus interval: time from start of cs to the start of the us. Cr assessed by presenting the cs alone. Cs and us occur randomly in same trial. Us and cs presented on different trials. Interstimulus interval- key is time from cs onset to us onset. Conditioning is optimal when cs predicts the us will occur soon. But modern theories indicate all procedures produce strong learning, it"s just not displayed. The organism learns not only the cs-us association, but when it occurs.
