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Old Tuesday, April 09, 2013
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Yes we can say that its a mixture of both.

Avoidance learning

Avoidance learning belongs to negative reinforcement schedules. The subject learns that a certain response will result in the termination or prevention of an aversive stimulus. There are two kinds of commonly used experimental settings: discriminated and free-operant avoidance learning.
Discriminated avoidance learning

In discriminated avoidance learning, a novel stimulus such as a light or a tone is followed by an aversive stimulus such as a shock (CS-US, similar to classical conditioning). During the first trials (called escape-trials) the animal usually experiences both the CS (Conditioned Stimulus) and the US (Unconditioned Stimulus), showing the operant response to terminate the aversive US. During later trials, the animal will learn to perform the response already during the presentation of the CS thus preventing the aversive US from occurring. Such trials are called "avoidance trials."

Free-operant avoidance learning

In this experimental session, no discrete stimulus is used to signal the occurrence of the aversive stimulus. Rather, the aversive stimulus (mostly shocks) are presented without explicit warning stimuli. There are two crucial time intervals determining the rate of avoidance learning. This first one is called the S-S-interval (shock-shock-interval). This is the amount of time which passes during successive presentations of the shock (unless the operant response is performed). The other one is called the R-S-interval (response-shock-interval) which specifies the length of the time interval following an operant response during which no shocks will be delivered. Note that each time the organism performs the operant response, the R-S-interval without shocks begins anew.

Two-process theory of avoidance

This theory was originally proposed in order to explain discriminated avoidance learning, in which an organism learns to avoid an aversive stimulus by escaping from a signal for that stimulus. The theory assumes that two processes take place:

a) Classical conditioning of fear
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During the first trials of the training, the organism experiences the pairing of a CS with an aversive US. The theory assumes that during these trials an association develops between the CS and the US through classical conditioning and, because of the aversive nature of the US, the CS comes to elicit a conditioned emotional reaction (CER) – "fear."
b) Reinforcement of the operant response by fear-reduction.
As a result of the first process, the CS now signals fear; this unpleasant emotional reaction serves to motivate operant responses, and those responses that terminate the CS are reinforced by fear termination. Although, after this training, the organism no longer experiences the aversive US, the term "avoidance" may be something of a misnomer, because the theory does not say that the organism "avoids" the US in the sense of anticipating it, but rather that the organism escapes an aversive internal state that is caused by the CS.
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