Table of Contents
What is Spontaneous Recovery
Spontaneous recovery refers to the sudden reappearance of a previously extinct conditioned response after the unconditioned stimulus has been removed for some time.
Spontaneous recovery can occur after two types of conditioning has taken place.
Classical conditioning – involuntary learning process through the association of neutral stimulus with a biologically potent stimulus that produces an unconditioned response.
Operant conditioning – voluntary learning through the use of rewards or punishment.
Spontaneous Recovery Examples – Classical Conditioning
In classical conditioning, also known as pavlovian conditioning, a previously neutral stimulus (NS) becomes conditioned when it is repeatedly paired with the unconditioned stimulus (US). This now conditioned stimulus (CS) can produce its own conditioned response (CR), which is usually very similar to the unconditioned response (UR).
However, some conditioned responses are vulnerable to extinction. If the conditioned stimulus continues to appear in the absence of the unconditioned stimulus, the conditioned response becomes weaker and weaker until it disappears, which is called the extinction procedure.
A famous example is Pavlov’s dogs. Ivan Pavlov, who coined the term pavlovian conditioning, experimented by sounding a bell repeatedly when he fed the dogs. Over time, they learned to associate the sound with food and salivated when they heard the sound. Then Pavlov started ringing the bell without giving food. Eventually, the dogs stopped salivating to the sound of the bell.
However, Pavlov noticed that even after a substantial amount of time had passed, the conditioned response would easily recover if the neutral stimulus and the unconditioned stimulus were paired again. Also though the dogs stopped salivating to the sound of the bell, their salivation recovered spontaneously after a “rest period.”1
Another example is that a child gets excited every day when they hear the ice cream truck music because their mother always buys them ice cream. When their mother stops buying, the child gradually learns to not associate the ice cream truck music with eating ice cream. After the truck stops coming for a few days and then returns, the child gets excited again when they hear the truck music.
Spontaneous Recovery Examples – Operant Conditioning
A trainer teaches a dog to sit by associating the command “Sit” with food. So the dog learns to sit whenever the trainer says the word. But after the trainer stops giving it food, it gradually stops responding to the command. Days later, the trainer tries again, and the dog sits.
Here is another example. A child runs to the door to greet Dad because he always brings home a new toy. After Dad stops bringing home toys, the child stops running to the door to greet him. After a few days, the child suddenly starts greeting their Dad at the door again.
How it Works
The fact that conditioned response can spontaneously recover suggests that extinction doesn’t erase the learned association. Instead, extinction inhibits the conditioned response. It appears that extinction forms new learning separate from the original conditioned learning2.
This new learning “extinguish” the conditioned response by inhibiting its expression instead of erasing or unlearning it.
Since the initial conditioned response never disappears, it eventually returns. Studies show that, with sufficient time, spontaneous recovery of the fear response occurs 100% in situations such as fear conditioning3.
Since new learning does not replace old ones, spontaneous recovery does not replace the extinction learning either. It simply exists in the presence of extinction learning4.
The extinction process creates a new learning memory. During spontaneous recovery, the reactivated memory from extinction competes with the reactivated memory from initial conditioning but fails5.
- 1.Rehman I, Mahabadi N, Rehman C. statpearls. June 2019. http://www.ncbi.nlm.nih.gov/books/NBK470326/.
- 2.Rescorla RA. Spontaneous Recovery. Learning & Memory. September 2004:501-509. doi:10.1101/lm.77504
- 3.Quirk GJ. Memory for Extinction of Conditioned Fear Is Long-lasting and Persists Following Spontaneous Recovery. Learning & Memory. November 2002:402-407. doi:10.1101/lm.49602
- 4.Bouton ME. Context, ambiguity, and unlearning: sources of relapse after behavioral extinction. Biological Psychiatry. November 2002:976-986. doi:10.1016/s0006-3223(02)01546-9
- 5.Laborda MA, Miller RR. Reactivated memories compete for expression after Pavlovian extinction. Behavioural Processes. May 2012:20-27. doi:10.1016/j.beproc.2012.01.012