Learning

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JENNIFER, A 45-YEAR-OLD MILITARY NURSE, LIVED quietly in a rural area of the United States with her spouse of 21 years and their two children before she served 19 months abroad during the Iraq war. In Iraq, she provided care to soldiers from different countries as well as to Iraqi civilians, prisoners, and militant extremists.

Jennifer served 4 months of her assignment in a prison hospital near Baghdad, where she witnessed many horrifying events. The prison was the target of relentless mortar fire, resulting in numerous deaths and serious casualties, including bloody injuries and loss of limbs. Jennifer worked 12- to 14-hour shifts, trying to avoid incoming fire while tending to some of the most gruesomely wounded cases. She frequently encountered the smell of burnt flesh and the sight of “young, mangled bodies” as part of her daily duties (Feczer & Bjorklund, 2009, p. 285).

This repetitive trauma took a toll on Jennifer, and when she returned to her home, it became evident that she had not left behind her war experiences. Jennifer thought about them repeatedly and they profoundly influenced her reactions to many aspects of everyday life. The sight of blood or the smell of cooking meat made her sick to her stomach, to the point that she had to stop eating meat. The previously innocent sound of a helicopter approaching, which in Iraq signalled that new wounded bodies were about to arrive, now created in Jennifer heightened feelings of fear and anxiety. She regularly awoke from nightmares concerning the most troubling aspects of her Iraq experiences, such as tending to soldiers with multiple amputations. In the words of the authors who described her case, Jennifer was “forever changed” by her Iraq experiences (Feczer & Bjorklund, 2009). And that is one reason why Jennifer’s story is a compelling, although disturbing, introduction to the topic of learning.

Much of what happened to Jennifer after she returned to her home reflects the operation of a kind of learning based on association. Sights, sounds, and smells in Iraq had become associated with negative emotions in a way that created an enduring bond, so that encountering similar sights, sounds, and smells at home elicited similarly intense negative feelings.

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LEARNING IS SHORTHAND FOR A COLLECTION OF DIFFERENT TECHNIQUES, procedures, and outcomes that produce changes in an organism’s behaviour. Learning psychologists have identified and studied as many as 40 different kinds of learning. However, there is a basic principle at the core of all of them. Learning involves the acquisition of new knowledge, skills, or responses from experience that results in a relatively permanent change in the state of the learner. This definition emphasizes these key ideas:

Think about Jennifer’s time in Iraq and you will see all of these elements: Experiences such as the association between the sound of an approaching helicopter and the arrival of wounded bodies changed the way Jennifer responded to certain situations in a way that lasted for years.

Learning can also occur in much simpler, nonassociative forms. You are probably familiar with the phenomenon of habituation, a general process in which repeated or prolonged exposure to a stimulus results in a gradual reduction in responding. If you have ever lived under the flight path of your local airport, near railroad tracks, or by a busy highway, you have probably noticed the deafening roar as a Boeing 737 made its way toward the landing strip, the clatter of a train speeding down the track, or the sound of traffic when you first moved in. After a while, the roar was not quite so deafening anymore and eventually you probably no longer noticed the sounds of the planes, trains, or automobiles in your vicinity. This welcome reduction in responding reflects the operation of habituation.

Habituation occurs even in the simplest organisms. For example, in the Memory chapter you learned about the sea slug Aplysia, studied in detail by Nobel Prize winner Eric Kandel (2006). Kandel and his colleagues showed clearly that Aplysia exhibits habituation: When lightly touched, the sea slug initially withdraws its gill, but the response gradually weakens after repeated light touches. In addition, Aplysia exhibits another simple form of learning known as sensitization, which occurs when presentation of a noxious stimulus leads to an increased response to a later stimulus. For example, Kandel found that after receiving a strong shock, Aplysia showed an increased gill withdrawal response to a light touch. In a similar manner, people whose houses have been broken into may later become hypersensitive to late-night sounds that would not have bothered them previously.

Although these simple kinds of learning are important, in this chapter we will focus on more complex kinds of learning that psychologists have studied intensively. As you will recall from the Psychology: Evolution of a Science chapter, a sizable chunk of psychology’s history was devoted to behaviourism, with its insistence on measuring only observable, quantifiable behaviour and its dismissal of mental activity as irrelevant and unknowable. Behaviourism was the major outlook of most psychologists working from the 1930s through the 1950s, the period during which most of the fundamental work on learning theory took place.

You might find the intersection of behaviourism and learning theory a bit surprising. After all, at one level learning seems abstract: Something intangible happens to you, and you think or behave differently thereafter. It seems logical that you would need to explain that transformation in terms of a change in mental outlook. However, most behaviourists argued that learning’s “permanent change in experience” could be demonstrated equally well in almost any organism: rats, dogs, pigeons, mice, pigs, or humans. From this perspective, behaviourists viewed learning as a purely behavioural activity requiring no mental activity.

In many ways the behaviourists were right. Much of what we know about how organisms learn comes directly from the behaviourists’ observations of behaviours. However, they also overstated their case. There are some important cognitive considerations (i.e., elements of mental activity) that need to be addressed in order to understand the learning process. In the first two sections of this chapter, we will discuss the development and basic principles of two major approaches to learning: classical conditioning and operant conditioning. We will then move on to see that some important kinds of learning occur simply by watching others, and that such observational learning plays an important role in the cultural transmission of behaviour. Next, we will discover that some kinds of learning can occur entirely outside of awareness. Finally, we will discuss learning in a context that should matter a lot to you: the classroom.

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