Traditionally, learning is divided into three categories: associative, nonassociative and observational. Associative learning aids us in anticipating future situations based on past experiences. It happens when we form connections among behaviours. Being able to anticipate the future is advantageous for survival. Two types of associative learning are classical conditioning and operant conditioning.

Nonassociative learning involves changes in the magnitude of responses to a single stimulus rather than the formation of connections between stimuli. Two important types of nonassociative learning are habituation and sensitization.

Classical Conditioning

In classical conditioning, we form associations between pairs of stimuli that occur sequentially in time. For example, if a child sees a wasp for the first time and gets stung, the child would remember the pain of the sting and associate it upon seeing wasps in the future and would likely be scared of wasps. Ivan Petrovich Pavlov is highly connected to the study of classical conditioning that the phenomenon is often referred to as Pavlovian conditioning. Pavlov first started being interested in the study of learning when he noticed his dogs had learned to anticipate the arrival of food. Instead of salivating when presented with food, Pavlov’s dogs began to salivate as soon as they are retrieved from their kennel or strapped into their harnesses. Pavlov realized the full significance of his observations: the dogs had formed an association between stimuli preceding the food and the arrival of the food itself. The dogs had recognised that certain actions were signals for the arrival of their food and begin to anticipate it before it even happens. Classical conditioning explains many of our learned emotional responses to our environment.

Operant Conditioning

In operant conditioning, we form associations between behaviors and their consequences. For example, if you go to sleep early, you will feel energized the next day. The association between a behavior and its consequences is referred to as operant or instrumental conditioning. Operant conditioning differs from classical conditioning along several dimensions. By definition, classical conditioning is based on an association between two stimuli, whereas operant conditioning occurs when a behavior is associated with its consequences. Classical conditioning generally works best with relatively involuntary behaviors, such as fear or salivation, whereas operant conditioning involves voluntary behaviors, like walking to class or petting a dog.

Habituation and Sensitization

Habituation reduces our reactions to repeated experiences in which we evaluated and concluded to be harmless. For example, getting increasingly comfortable in a new house after adapting to the new atmospheric conditions. Sensitization, on the other hand, increases our reactions to a wide range of stimuli following exposure to one strong stimulus. For example, after being involved in a car accident, one may become afraid to sit in cars or even travel on the roads. Habituation ensures that we do not waste precious resources monitoring low-priority stimuli. Sensitization is particularly useful in threatening situations. After detecting one harmful stimulus, raising our level of responsiveness should improve reaction time in the event of future danger.