Spontaneous recovery
Encyclopedia
Spontaneous recovery is a phenomenon first seen in Pavlovian conditioning and then later discovered in memory functioning. The general pattern of spontaneous recovery found in Pavlovian conditioning in animals essentially encompasses two varying habits learned by the animal where there is an initial overpowering presence of habit 2 over habit 1 and then over time, habit 1 regains empowerment over habit 2. This is parallel to learning in human memory.
A classic experiment that demonstrates spontaneous recovery was conducted by Rescorla. Original acquisition was conducted with two different stimuli (sucrose and a solid food pellet) which was delivered by cups recessed in one of the walls of the experimental chamber. Rescorla used infrared detectors, which are photodetectors that react to infrared (IR) radiation, that identified each time the rat poked its head into the food cups. One of the unconditioned stimuli was signaled by a noise (a conditioned stimulus, CS) and the other unconditioned stimulus was signaled by a light. As conditioning progressed each CS quickly came to elicit the goal, the conditioned response, with the two CSs eliciting the same level of responding.
Two extinction sessions comprising sixteen trials each were then conducted. Each session was followed by a series of four test trials. The experimental manipulation of primary interest was the interval between the end of the extinction training and the test trials. For one of the conditioned stimuli (S1) there was an eight-day period separating the extinction training and the test trials. For the second CS (S2) the test trials were started immediately after the extinction training.
What Rescorla et al.'s experiment showed was that during the course of extinction training responding declined similarly in both S1 and S2 conditions. However, responding remained suppressed during the test trials conducted immediately after the extinction training whereas responding substantially recovered in the S1 condition where there was a rest period of eight days.
Spontaneous recovery may help explain why it is so hard to overcome drug addictions. For example, cocaine
addicts who are thought to be "cured" can experience an irresistible impulse to use the drug again if they are subsequently confronted by a stimulus with strong connections to the drug, such as a white powder.
, where the relation of inhibitory process during learning between competing lists. Specifically, Briggs focused on retroactive interference, a psychological theory of memory stating that learning something new impedes the retrieval of previously related learned information. Briggs studied retroactive interference by composing a list of 12 adjectives randomly paired (ex: A–B) and afterward have participants partake in a cued-recall test and cyclically continue until mastery. Thus, once List 1 is fully learned, participants are thereafter given a new similarly structured list to learn, but this time B items are replaced by C items (ex: A–C). After mastery of List 2, Briggs then performed a recall procedure where he gave an A list item and asked the participant to recall whichever pair came to their mind first. (This gives the participant an unconscious choice of response, where whichever list item has the strongest association is used as a response.) The results found that immediate recall using Briggs' modified recall procedure led to higher rate of responses from list C. Thus, this is evidence for retroactive interference, where the learning of A–C led to the impeding of previous learning of A–B. Although it was uncertain whether this was due to competition among the items in opposing lists or to unlearning, Briggs' subsequent delay testing (1 day), led to the discovery of spontaneous recovery in human memory.
Proposed explanations
Since the aforementioned spontaneous recovery was initially shocking, various explanations attempted to explain the phenomenon. Firstly, due to the span of time of approximately 24 hours, lists A–B and A–C reached fairly equivalent degrees of unlearning (hypothesized due to the relatively large time span compared to a difference of one hour prior). Secondly, the higher recall of list B items was hypothesized to be due to a possible retrieval of A–B list items during the learning of A–C items.
Models that predict spontaneous recovery
Estes (1955) was the first to explore the processes underlying spontaneous recovery. He investigated the changes and hypothesized that spontaneous recovery may be accounted for by random fluctuations in stimulus conditions. His findings included a discovery that certain conditions can dually impede performance while enhancing long-term retention. Estes (1955) focused on contextual cues as the condition which initially challenged recovery of list B in Briggs' study.
Contextual drift was later also proposed as a building block of spontaneous recovery. Since contextual drift is theorized to affect memory and learning, then at the time of initial testing, list 2 (C) is closer in context to list A than list 1 (B). However, as time passes, contextual drift weakens the strength of both list association equivalently.
The neural-network model predicts spontaneous recovery through the storage of distributed representations.
However, no one has yet been able to fully explain spontaneous recovery. Thus, this phenomenon has been referred to as "one of the unresolved issues of interference theory".
Spontaneous recovery in Pavlovian conditioning
Spontaneous recovery is a term that is commonly associated with learning and conditioning. It is commonly referred to as "one of the basic phenomena of Pavlovian conditioning"; however spontaneous recovery can also be seen in a variety of other designs. It is typically noted in relation to extinction. It has been widely accepted by many scholars that extinction does not erase what has previously been learned, a conditioned response (CR), but produces a decline in conditioned behavior. Spontaneous recovery is just one of many procedures that help scholars confirm the belief that extinction is not a device that can erase a conditioned behavior from an organism. Spontaneous recovery typically occurs during a rest period between extinction training sessions. It is defined as increased recovery of a conditioned behavior that occurs during a rest period with no visible reason for its occurrence, which is why it is labeled spontaneous.A classic experiment that demonstrates spontaneous recovery was conducted by Rescorla. Original acquisition was conducted with two different stimuli (sucrose and a solid food pellet) which was delivered by cups recessed in one of the walls of the experimental chamber. Rescorla used infrared detectors, which are photodetectors that react to infrared (IR) radiation, that identified each time the rat poked its head into the food cups. One of the unconditioned stimuli was signaled by a noise (a conditioned stimulus, CS) and the other unconditioned stimulus was signaled by a light. As conditioning progressed each CS quickly came to elicit the goal, the conditioned response, with the two CSs eliciting the same level of responding.
Two extinction sessions comprising sixteen trials each were then conducted. Each session was followed by a series of four test trials. The experimental manipulation of primary interest was the interval between the end of the extinction training and the test trials. For one of the conditioned stimuli (S1) there was an eight-day period separating the extinction training and the test trials. For the second CS (S2) the test trials were started immediately after the extinction training.
What Rescorla et al.'s experiment showed was that during the course of extinction training responding declined similarly in both S1 and S2 conditions. However, responding remained suppressed during the test trials conducted immediately after the extinction training whereas responding substantially recovered in the S1 condition where there was a rest period of eight days.
Spontaneous recovery may help explain why it is so hard to overcome drug addictions. For example, cocaine
Cocaine
Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is a stimulant of the central nervous system, an appetite suppressant, and a topical anesthetic...
addicts who are thought to be "cured" can experience an irresistible impulse to use the drug again if they are subsequently confronted by a stimulus with strong connections to the drug, such as a white powder.
Retroactive interference
The phenomenon of spontaneous recovery and as it pertains to human memory can be traced back to a study done by George Edward BriggsGeorge Edward Briggs
George Edward Briggs was a British botanist.He was born in Grimsby, Lincolnshire, the eldest son of Walker Thomas and Susan Briggs....
, where the relation of inhibitory process during learning between competing lists. Specifically, Briggs focused on retroactive interference, a psychological theory of memory stating that learning something new impedes the retrieval of previously related learned information. Briggs studied retroactive interference by composing a list of 12 adjectives randomly paired (ex: A–B) and afterward have participants partake in a cued-recall test and cyclically continue until mastery. Thus, once List 1 is fully learned, participants are thereafter given a new similarly structured list to learn, but this time B items are replaced by C items (ex: A–C). After mastery of List 2, Briggs then performed a recall procedure where he gave an A list item and asked the participant to recall whichever pair came to their mind first. (This gives the participant an unconscious choice of response, where whichever list item has the strongest association is used as a response.) The results found that immediate recall using Briggs' modified recall procedure led to higher rate of responses from list C. Thus, this is evidence for retroactive interference, where the learning of A–C led to the impeding of previous learning of A–B. Although it was uncertain whether this was due to competition among the items in opposing lists or to unlearning, Briggs' subsequent delay testing (1 day), led to the discovery of spontaneous recovery in human memory.
Spontaneous recovery in Briggs' study
Although responses from list B decreased quickly after learning list C, after re-testing a day later, the results took a dramatic shift. Retroactive interference disappeared and a modified recall procedure led to an increase in responses from list B.Proposed explanations
Since the aforementioned spontaneous recovery was initially shocking, various explanations attempted to explain the phenomenon. Firstly, due to the span of time of approximately 24 hours, lists A–B and A–C reached fairly equivalent degrees of unlearning (hypothesized due to the relatively large time span compared to a difference of one hour prior). Secondly, the higher recall of list B items was hypothesized to be due to a possible retrieval of A–B list items during the learning of A–C items.
Models that predict spontaneous recovery
Estes (1955) was the first to explore the processes underlying spontaneous recovery. He investigated the changes and hypothesized that spontaneous recovery may be accounted for by random fluctuations in stimulus conditions. His findings included a discovery that certain conditions can dually impede performance while enhancing long-term retention. Estes (1955) focused on contextual cues as the condition which initially challenged recovery of list B in Briggs' study.
Contextual drift was later also proposed as a building block of spontaneous recovery. Since contextual drift is theorized to affect memory and learning, then at the time of initial testing, list 2 (C) is closer in context to list A than list 1 (B). However, as time passes, contextual drift weakens the strength of both list association equivalently.
The neural-network model predicts spontaneous recovery through the storage of distributed representations.
However, no one has yet been able to fully explain spontaneous recovery. Thus, this phenomenon has been referred to as "one of the unresolved issues of interference theory".
- Pavlov's dogs
- Retroactive Interference
- Associative Unlearning