Psychology- a Complete Introduction
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Some reinforcement can be simultaneously positive and negative, such as a drug addict taking drugs for the added euphoria (a positive feeling) and eliminating withdrawal symptoms (which would be a negative feeling). Or, in a warm room, a blast of air conditioning serves as positive reinforcement because it is pleasantly cool and as negative reinforcement because it removes uncomfortable hot air. Both positive and negative reinforcement increase behaviour. Most people, especially children, will learn to follow instruction by a mix of positive and negative reinforcement.
PRIMARY AND SECONDARY REINFORCERS
A primary reinforcer, sometimes called an unconditioned reinforcer, is a stimulus that does not require pairing to function as a reinforcer and most likely has obtained this function through evolution and its role in survival. Examples of primary reinforcers include sleep, food and water. The reinforcing value of primary reinforcers can vary. Thus, one person may prefer one type of food while another hates it. Or one person may eat lots of food while another eats very little. So even though food is a primary reinforcer for both individuals, the value of food as a reinforcer differs between them.
A secondary reinforcer, sometimes called a conditioned reinforcer, is a stimulus or situation that has acquired its function as a reinforcer after pairing with a stimulus that functions as a reinforcer. Money is a secondary reinforcer that has only learned value.
Spotlight: The Premack Principle
The Premack Principle is a special case of reinforcement coined by David Premack (1959). This states that a highly preferred activity can be used effectively as a reinforcer for a less preferred activity. The principle is often considered in parenting situations, such as ‘If you clear the table, you can go and play outside’ or ‘Eat your vegetables and you can have ice cream.’ As a result, it is sometimes called Grandma’s Law.
BEHAVIOUR MODIFICATION
Behaviour modification is a set of therapies/techniques based on operant conditioning (Skinner 1938, 1953). The main principle comprises changing environmental events that are related to a person’s behaviour – for example the reinforcement of desired behaviours and ignoring or punishing undesired ones. This is used in workplaces, in schools and other environments to shape behaviour.
Shaping is when reinforcement is used to build up desired complex behaviours; the behaviours are broken into smaller parts and each part is reinforced before moving on to the next segment in the sequence. For example, a child who is afraid of dogs might be rewarded for being in the same room as a dog. Once that behaviour becomes accepted, he might then be rewarded for sitting near the dog. Eventually, he will be reinforced for stroking the dog and so on.
A token economy is a system of behaviour modification based on the systematic reinforcement of target behaviour. The reinforcers are symbols or ‘tokens’ that can be exchanged for other reinforcers. Token economies are often used in schools and mental health settings to shape appropriate behaviour.
REINFORCEMENT SCHEDULES
Schedules of reinforcement are the rules that are used to decide when reinforcers (or even punishers) are presented in relation to a specified operant behaviour. These rules are defined in terms of the time and/or the number of responses required in order for the reinforcement or reward to appear. A reinforcement schedule is a tool in operant conditioning that allows the experimenter or trainer to control the timing and frequency of reinforcement in order to elicit a target behaviour series from a participant. There are three main types of schedule: continuous, ratio and interval.
Continuous reinforcement is a schedule of reinforcement in which every occurrence of the instrumental or operant response is followed by the reinforcer. For example, if Skinner’s rats received a food pellet each time they pressed the lever, that would be continuous reinforcement. Parents toilet training their toddlers usually start with continuous reinforcement. This type of schedule is the least resistant to extinction since as soon as the reinforcement stops, the behaviour will stop too (unless it becomes its own reward, as tends to happen with toilet training – children usually find accidents distressing and thus maintain toileting behaviour even when the external rewards have stopped).
With ratio schedules, the presentation of the reward depends on the number of operant responses that the individual has performed. There are two types of ratio schedule:
• Fixed ratio schedules: these deliver reinforcement after a set number of responses. Thus Skinner’s rat might receive a food pellet after every fifth press. In real life, this might work by rewarding an estate agent with a bonus for every five houses sold. Extinction will occur when the reward is stopped.
• Variable ratio schedules: here the reinforcement occurs after a variable number of responses. A real-world example is slot machines (because, though the probability of hitting the jackpot is constant, the number of lever presses needed to hit the jackpot is variable). The variable ratio schedule is the most resistant to extinction.
Interval schedules require a minimum amount of time that must pass between successive reinforced responses (e.g. five minutes). Responses that are made before this time has elapsed are not reinforced. There are also two types of interval schedule:
• Fixed interval: this is where there is a fixed amount of time between each reinforcer; a real life example of this is when someone is paid hourly. Extinction will occur quickly if the reinforcer is stopped.
• Variable interval: reinforced on an average amount of time that varies from trial to trial. Fishing is a good example of a variable interval schedule: the fisherman/woman knows that they might have to wait a long time before they catch their fish. This schedule is resistant to extinction in that the behaviour will continue for quite a while after reinforcement stops.
Social Learning Theory
‘Learning would be exceedingly laborious, not to mention hazardous, if people had to rely solely on the effects of their own actions to inform them what to do. Fortunately, most human behavior is learned observationally through modeling: from observing others one forms an idea of how new behaviors are performed, and on later occasions this coded information serves as a guide for action.’
Albert Bandura, Social Learning Theory (Englewood Cliffs, NJ: Prentice-Hall, 1977)
Taking a different perspective to the behaviourist view of learning as outlined so far in this chapter is Albert Bandura’s Social Learning Theory (SLT; 1977). Albert Bandura (born 1925) is an eminent psychologist at Stanford University. SLT states that people can learn from one other, via observation, imitation and modelling, not just through conditioning. Unlike Skinner, Bandura believed that humans are active information processors and think about the relationship between their behaviour and its consequences. Observational learning could not occur unless cognitive processes were at work; because the social learning approach takes into account the cognitive factors that mediate between stimuli and responses, it addresses one of the most important criticisms of behaviourism – that is, its neglect of thinking or cognitive processes.
These are the key tenets of Social Learning Theory:
• Learning is not just behavioural, based on conditioning; rather, it is a cognitive process that takes place in a social context.
• Learning can occur vicariously, through the observation of a behaviour and the consequences of that behaviour.
• Learning can occur without an observable change in a person’s behaviour.
While the role of reinforcement in learning is acknowledged, SLT states that there are other factors that contribute, too.
Reciprocal determinism states that, just as an individual’s behaviour is influenced by the environment, the environment is also influenced by the individual’s behaviour. Thus, for example, a child may have learned by their home life to be aggressive, but by being aggressive they also change the way others act towards them.
Case study: Bobo doll experiments
Both of the shooters of the Columbine School massacre in 1999 watched violent movies and played violent
video games, and many blamed these types of media for what happened. But what exactly is the impact of violent media on the behaviour of children and youth? Can children really learn to be violent by watching others? In 1961 Bandura and colleagues conducted the now-famous Bobo doll experiments. The Bobo doll was a child-sized inflatable doll with a weighted bottom that causes it to pop back up after being knocked down. Preschool-aged children were divided into three groups: one group that observed an adult behaving aggressively towards the Bobo doll (punching, kicking, striking with a mallet, yelling), another group that observed the adult playing peacefully, and a control group.
Later, the children were allowed to play independently in the playroom, which contained a variety of aggressive and non-aggressive toys, including the Bobo doll. Participants’ acts of verbal and physical aggression towards the Bobo doll were then recorded. Results revealed significant group differences, one of which was that the children exposed to the aggressive model were more likely to imitate what they had seen and behave aggressively towards the doll. Bandura and colleagues argued that the results supported the idea that children can rapidly learn new behaviours through the process of observation and imitation, and that this occurs even in the absence of any kind of reinforcement.
Some critics of these studies, however, argue that the behaviour of the children in Bandura’s studies was significantly influenced by demand characteristics and that they were, in effect, deliberately producing the behaviour they thought the experimenters wanted to see.
Observation is the central tenet of SLT but observational learning can be influenced by a variety of factors. For example, the degree of modelling (or copying the behaviour of a model) can depend on who that model is; we are more likely to learn from and copy the behaviour of someone we like and who is similar to us (something that advertisers and marketers will use to their advantage where possible). Learning is also influenced by the learner themselves; the learner has to be paying attention to the model, be able to retain the information they observe, be capable of reproducing it and be motivated to do so. All these factors can influence the likelihood of social learning taking place.
Spotlight: The fate of Bandura’s Bobo doll
The original Bobo doll can be seen in the Center for the History of Psychology at the University of Akron, after being donated by Bandura in 2010. It is one of their most popular exhibits.
Dig deeper
See Thorndike’s puzzle box in action at
http://www.simplypsychology.org/edward-thorndike.html
Can birds read? Watch a bird demonstrate operant conditioning in a Skinner box:
http://www.simplypsychology.org/operant-conditioning.html
To see Bandura’s Bobo doll study, see:
https://www.youtube.com/watch?v=dmBqwWlJg8U
Fact-check
1 What is learning?
a A permanent change in behaviour as a result of experience
b A permanent change in attitude as a result of experience
c A temporary change in behaviour as a result of experience
d A relatively lasting change in behaviour as a result of experience
2 What is classical conditioning?
a The process by which dogs salivate
b A learning process in which an association is made between a previously neutral stimulus and a stimulus that naturally evokes a response
c A type of learning in which an individual’s behaviour is modified by its antecedents (things that preceded it) and consequences (things that follow it)
d A procedure that focuses on using either reinforcement or punishment to increase or decrease a behaviour
3 What is operant conditioning?
a The process by which dogs salivate
b A learning process in which an association is made between a previously neutral stimulus and a stimulus that naturally evokes a response
c A type of learning in which an individual’s behaviour is modified by its antecedents (things that preceded it) and consequences (things that follow it)
d A procedure that focuses on using either reinforcement or punishment to increase or decrease a behaviour
4 Thorndike’s ‘Law of Effect’ states that:
a Any behaviour that is followed by pleasant consequences is likely to be repeated, and any behaviour followed by unpleasant consequences is likely to be stopped
b Any behaviour that is followed by unpleasant consequences is likely to be repeated, and any behaviour followed by pleasant consequences is likely to be stopped
c A highly preferred activity can be used effectively as a reinforcer for a less preferred activity
d Reinforcement can be used to build up desired complex behaviours
5 The removal of an unpleasant reinforcer to strengthen behaviour is referred to as:
a Positive reinforcement
b Negative reinforcement
c Punishment
d Extinction
6 Shaping is:
a When reinforcement is used to build up desired complex behaviours
b A token economy
c Used with ratio schedules
d Used with interval schedules
7 Fixed schedules of reinforcement are:
a The most efficient
b Used in schools
c Where there is a fixed amount of time or number of responses before a reward appears
d Where there is a variable amount of time or number of responses before a reward appears
8 With which of the following processes does social learning not occur?
a Observation
b Imitation
c Modelling
d Change in behaviour
9 Reciprocal determinism is the process by which:
a There is a variable amount of time or number of responses before a reward appears
b Just as an individual’s behaviour is influenced by the environment, the environment is also influenced by the individual’s behaviour
c A highly preferred activity can be used effectively as a reinforcer for a less preferred activity
d Shaping occurs
10 Which of the following factors does not influence the likelihood of social learning taking place?
a Who the model is
b How similar we are to them
c How motivated we are
d How old we are
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Language and thought
Language and thinking processes are thought by many to go hand in hand; while it is theoretically possible to have thought without language (and language without thought), the two processes certainly interact quite early in development. Most psychologists are of the view that the two processes are very much interlinked, which is why they are presented together in this chapter. Other aspects of cognition that depend on these processes, such as reasoning, problem-solving and creativity, are also explored in this chapter.
Language acquisition
Language acquisition is the process by which we learn to perceive and understand language, as well as to use words and construct sentences to communicate (this is distinguished from second-language acquisition, which deals with the acquisition, in both children and adults, of additional languages). It is the complex linguistical skill that humans have that sets them apart from other animals; while other species do communicate using a limited number of meaningful vocalizations, there is no other species known to date that can express infinite ideas (sentences) with a limited set of symbols (speech sounds and words) as humans can.
The capacity to successfully use language requires one to acquire a range of complex tools including phonology, morphology, syntax, semantics and an extensive vocabulary. Language need not be verbally expressed – sign language would come in the same category in terms of the processes of acquisition.
There are thought to be two main guiding principles in first-language acquisition:
• Speech perception always precedes speech production (children understand language be
fore they can speak it; this understanding is sometimes called receptive language, as oppose to expressive language, which is spoken)
• Language is a gradually evolving system by which a child learns a language one step at a time, beginning with the distinction between individual phonemes (the smallest unit of sound in a language).
A major debate in understanding language acquisition is how these capacities are picked up by young children. Behaviourists such as Skinner (1957) argue that children learn language based on behaviourist reinforcement principles (including imitation and reinforcement), by associating words with meanings. Correct utterances are positively reinforced when the child realizes the communicative value of words and phrases; for example, a child who can say the word ‘drink’ is more likely to be rewarded with what they want than a child who cannot articulate the word (or an approximation of the word). According to this view, children learn words by associating sounds with objects, actions and events. They also learn words and syntax by imitating others. Adults enable children to learn words and syntax by reinforcing correct speech.
Nativists, such as Noam Chomsky (born 1928), however, disagree with this approach, arguing that children would never acquire the tools needed for processing the infinite number of sentences that we can process, if the language acquisition mechanism was dependent on language input alone; as there are infinite ways of putting sentences together, these cannot possibly all be learned by imitation. In addition, learning alone cannot account for the rapid rate at which children acquire language. When you consider the hugely complex nature of human language with its complicated grammatical structures, and compare this with the relatively limited cognitive ability of a small child, you can appreciate why Chomsky felt that there must be something other than learning that drives language acquisition. Chomsky decided that the process of language acquisition in infants must be biologically driven. Otherwise, he argued, it is hard to explain how children, within the first five years of life, are able to grasp the complex, grammatical rules of their native language – complexities that most adults are unable to master anywhere near as well. Indeed, the ‘critical period’ for language acquisition seems to be in the first five years; after the age of seven, our ability to learn a language declines dramatically.