Fear Conditioning

Learning to associate unpleasant occurrences with the environmental cues that anticipate such events is a necessary survival skill in animals. The fear conditioning paradigm exemplifies this type of associative learning. For some people, conditional dread could be extremely intense and long-lasting.

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Classical Conditioning

Classical conditioning, also known as Pavlov (classical conditioning)ian conditioning, is the process of learning through associating a neutral input with a physiologically powerful unpleasant response.

Pavlov (classical conditioning) noticed that his dogs salivated whenever he entered the room, even if he did not bring food, since the dogs linked his presence with getting fed.

Pavlov (classical conditioning)’s entry was a neutral stimulus (NS) that did not elicit a reaction in the dogs prior to training. However, after bringing food, an unconditioned stimulus (US), with him every time he entered the room, the entry became a conditioned stimulus (CS) that may cause the dogs to salivate automatically, a phenomenon known as the conditioned responsivity.

Pavlov (classical conditioning)’s entry was a neutral stimulus (NS) that did not elicit a reaction in the dogs prior to training. However, after bringing food, an unconditioned stimulus (US), with him every time he entered the room, the entrance became a conditioned stimulus (CS) that may cause the dogs to salivate automatically, a phenomenon known as the conditioned response (CR).

What Is Fear Conditioning

Fear conditioning is a kind of classical conditioning in which participants learn that specific environmental stimuli (CS) might predict the occurrence of unpleasant events (CR).

It is the technique by which we learn to be afraid of people, objects, locations, and events. This type of fear learning can help us survive in the face of future challenges throughout evolution.

Although conditioned fear is intended to be a survival strategy, uncontrolled conditioned fear may contribute to fear and anxiety disorders in humans, such as panic disorder, particular phobias, or post-traumatic stress disorder (PTSD).

The “Little Albert” Experiment

John Watson and Rosalie Rayner devised a contentious experiment with infant Albert in the 1920s.

The objective was to instil dread of a white rat in the baby. Little Albert had no fear of the rat prior to the trial.

After introducing the rat, a loud and aversive noise was made in the experiment. Watson created the loud, unpleasant noise by hitting a hammer against a hanging steel bar in order to elicit a terror response in tiny Albert. The infant was startled abruptly and burst into a bout of wailing. After numerous repetitions of this technique, tiny Albert began to fear the rat itself.

Even when the rat was not accompanied by the unpleasant sound, young Albert displayed instinctive fear responses such as falling over, sobbing, and crawling away from the rat.

It should be noted that this harsh experiment would not be allowed under contemporary ethical standards.

Little Albert had discovered that a benign conditioned stimulus (CS, the white rat) predicted the appearance of a nasty unconditional stimulus (US, the loud noise), resulting in a conditioned reaction (CR, crying). This experiment demonstrates fear psychology’s classical conditioning.

Cued and Contextual Fear Conditioning

A context is a collection of conditions that surround an occurrence. They are generally multimodal, diffuse, and ever-present. In addition to places, context might encompass geographical, temporal (time), interoceptive (e.g. hunger, stress), cognitive (how information is encoded and retrieved), social, and cultural interactions.

When a CS is a static environment context, such as a room, the effect is known as contextual fear conditioning. In this situation, the conditioned dread is linked to the setting. CR is activated when the conditioned individual is returned to the same situation. The conditioned fear is linked with a trigger in this situation.

Fear Extinction vs Fear Conditioning

When a conditioned individual is repeatedly exposed to the fear-inducing CS in the absence of the unpleasant US, the conditioned fear response diminishes and finally disappears. This is known as fear extinction, and it reduces the predictive power of the CS as to the occurrence of the US.

Extinction is not synonymous with unlearning or forgetting. It is, rather, a new related learning of fear inhibition.

According to human research, terror memories can endure for years with minimal fading. As a result, extinction does not eliminate the fear memory. However, it forms a new memory in which the CS is associated with the lack of the US.

Development of Fear Experiments

Fear training in rats is widely used by behavioural neuroscience researchers to explore the phenomena.

In normal fear conditioning research, the unpleasant stimuli is not delivered to the rat or rodent in the home cage. The animal is then placed in a new habitat, subjected to an unpleasant stimuli, such as foot shock, and then withdrawn. If it is reintroduced to the same “new” environment, it will typically exhibit frozen behaviour or variations in heart rate if it has become fear conditioned.

Scientists discovered that injuries to the amygdala, specifically the brain regions in the basolateral amygdala, can inhibit the learning and expression of fear.

Fear and the Brain

It is critical for survival to be able to predict threats using neutral cues. However, anxiety disorders such as posttraumatic stress disorder (PTSD) occur when this sort of conditioned fear fails to fade when it is no longer a danger. Conditioning memories of horrific experiences can produce severe conditioned fear reactions in people suffering with PTSD for decades after the danger has passed.

Not everyone who is subjected to conditioning events develops problems. According to lesion studies, the neural circuits implicated in fear acquisition and extinction include brain areas in the amygdala, hippocampus, and medial prefrontal cortex. These networks are dysfunctional.

References

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