Approaches in Psychology AQA A level (Yr12) Component 2

Transcription

1 Approaches in Psychology AQA A level (Yr12) Component 2 Paper 2 Candidates should be able to: Approaches in Psychology 1. Origins of Psychology: Wundt, introspection and the emergence of Psychology as a science 2. Learning approaches: Behaviourism; Classical conditioning - Pavlov, Operant conditioning - Skinner, Social Learning theory Bandura 3. Cognitive approach: study of internal mental processes, schema theory, theoretical and computer models to explain mental processes. Emergence of cognitive neuroscience 4. Biological approach: influence of genes, biological structures and neurochemistry on behaviour. Genotype and phenotype, genetic and evolutionary basis of behaviour GREEN AMBER RED 1

2 1) Origins of Psychology In contrast to the natural sciences (physics, chemistry and biology) is a relatively new scientific discipline. It has its roots in 17 th and early 19 th century philosophy and was indeed once known as experimental philosophy. Early influences included Rene Descartes, and his concept of Cartesian dualism, which simply means that the mind and body are separate entities, the brain is not the same as the mind. This is a clear starting point for psychology. The work of John Locke and his concept of empiricism, the belief that all knowledge is derived from sensory experience and can be studied using the scientific method also had an influence on the emergence of psychology as a science. Finally, the evolutionary theories of Charles Darwin set the stage for the emergence of psychology as we know it today. In 1873 Wilhelm Wundt published the first book on psychology Principles of Physiological Psychology and in 1879 opened the first psychology laboratory in Leipzig, Germany. His approach to psychology was to study the structure of the human mind, by breaking down behaviours into their basic elements, hence his approach became known as structuralism. 2

3 Wundt used introspection to investigate the human mind. Introspection comes from Latin and means looking into. Basically, participants were asked to reflect on their own cognitive processes and describe them. Wundt established psychology as a science by using the scientific method. Introspection may not seem particularly scientific, but it is still used today to gain access to cognitive processes. For example, Griffiths (1994) used introspection to study the cognitive processes of fruit machine gamblers. He asked then to think aloud whilst playing a fruit machine into a microphone on their lapel. Csikzentmilyi and Hunter (2003) used introspection to study happiness in their work in the area of positive psychology. Psychology Timeline Date (approx.) Dominant Approach/Perspective 1900s Freud Psychodynamic approach s Behaviourism 1950s Humanism 1960s Cognitive Psychology 1960s Social Psychology 1980s Biological approach 2000s Cognitive Neuroscience Task : - Outline two criticisms of introspection as a method of investigation. (2 + 2 marks) 3

4 2) Learning theory Behaviourism - Also known as learning theory Key Study: - Bandura, Ross & Ross (Griffiths could also be seen as a Behaviourist study as people learn to Gambling through reinforcement, Savage-Rumbaugh as Kanzi learnt language through imitation and reinforcement.) Behaviourists insist that psychology should be the study of behaviour, rather than the inner workings of the mind. Unlike mental processes, behaviour can be directly observed. The behaviour model, therefore, has a scientific approach, as it is based on observation and measurement within a laboratory. Behaviourism was first formulated around the beginning of the 20 th century. According to this model all behaviour, both normal and abnormal is learnt by a process known as conditioning. There are three main ways in which we learn behaviour: - Classical Conditioning, Operant Conditioning and Social Learning Theory. 1) Classical Conditioning Classical or Pavlovian conditioning involves learning new behaviour through association between two stimuli. The concept of Classical Conditioning was first formulated by Ivan Pavlov, who was investigating the salivatory reflex in dogs. The salivatory reflex is a response, which occurs automatically when food is placed on the dog s tongue. He noticed that dogs salivated in response to anything associated with the feeding routine (e.g. dish, person). By ringing a bell prior to feeding Pavlov could condition (train) the dogs to salivate just in response to the bell. Key Terms: - Unconditioned Stimulus (UCS) = food touching the tongue Unconditioned Response (UCR) = Salivation Conditioned Stimulus (CS) = Bell Conditioned Response (CR) = Salivation 4

5 At the start f the experiment, the CS does not cause a reflex response by itself. After many pairing (the exact number depends on how quickly the animal learns), with the UCS eventually the dog salivates just in response to the bell. This is called learning through association. Task: - Using the key terms draw a diagram to illustrate Classical Conditioning in Pavlov s Dogs. The first stage has been completed for you. 1) UCS (food) = UCR (Salivation) 2) 3) Application of Classical Conditioning to abnormal behaviour Most learnt behaviours are useful. However, sometimes maladaptive behaviours are learnt. Watson & Rayner (1920) applied the principles of Classical Conditioning to humans. They succeeded in inducing a fear of white rats (phobia) in an 11-month-old child. Watson & Rayner discovered that Little Albert, in common with most small children, displayed a fear response when he heard a loud noise. They made a loud noise by hitting a steel bar with a hammer behind him. This loud noise was the UCS in the experiment and fear was the UCR. Originally, Albert showed no fear of the white rat (CS) and played quite happily with it. However, after several pairing of the loud noise (UCS) and the white rat (CS), he displayed fear (UCR) in response to just the white rat. Little Albert had learnt to fear and avoid white rats without the loud noise being present. He had been conditioned to associate white rats with fear. However, Little Albert generalised this fear to other white fluffy things including Dr. Watson wearing a white beard! Task: - Draw a classical conditioning diagram for little Albert. 1) 2) 3) 5

6 2) Operant Conditioning This was developed by B F Skinner ( ). In operant conditioning behaviour is shaped through reinforcement. Positive reinforcement encourages behaviour to be repeated, by using rewards (e.g. training your dog with chocolate drops). Negative reinforcement behaviour with negative outcomes tends not to be repeated (e.g. a child who burns itself of the oven learns not to touch the oven). Punishment decreases the likelihood that behaviour is repeated. However, punishment has been found to ineffective as a negative reinforcement. This is because it is not a direct consequence of the behaviour. Children who are punished often simply find ways to avoid detection and the punishment rather than modify their behaviour. This model can explain way people persist with maladaptive behaviour. For example, the naughty child may continue with bad behaviour, despite of punishment, because he/she is actually being positively reinforced with attention. Many parents and teachers ignore good behaviour. To effectively shape a child s behaviour it would be preferable to ignore bad behaviour, where practical, and praise good behaviour. Skinner (1935) designed an experiment to demonstrate the principles of operant conditioning. A rat or pigeon was placed in a box (Skinner box) 6

7 How does the Skinner box demonstrate operant conditioning? Schedules of reinforcement In the case of the Skinner box, if a food reinforcer is not dispensed for every single lever press, but to a predetermined schedule then different response patters will emerge. Skinner experimented by using different ratio schedules e.g. 1:5 a food pellet was dispensed every 5 th lever press. He discovered that unpredictable reinforcement was more successful for conditioning behaviour than continuous reinforcement. Why so you think this is? (Hint: Gambling) 7

8 3) Social Learning Theory A later development of behaviourism was Social Learning Theory (SLT). The term was introduced by Bandura in the 1960s. He was studying aggression in children after they had been exposed to aggressive role models. In SLT learning is through indirect observation. Individuals observe role models and the consequences of their actions. If the consequences are positive (or at least not punished) they imitate the behaviour. For example, if children observe a naughty child, not being punished, and in fact benefiting from their action through teacher attention, they are likely to copy. Evaluation of Behaviourism Strengths Weaknesses 8

9 4) Cognitive Approach The cognitive approach suggests that all behaviour is preceded by a thought and that thought processes can and should be studied scientifically. However, there is a problem we can only study thought processes by introspection or inference from behaviours. Cognitive Psychology s main areas of study are: - memory language problem solving perception attention Early research centred on human experimentation, then moved on to computer model analogies and now makes use of advances in cognitive neuroscience, using the latest brain scanning technologies. Computer Analogies Cognitive Psychology suggests that thought processes precede all behaviour. It uses the computer analogy, which suggests that the brain works in much the same way as a computer. Information is taken in via the five senses, processed by the brain and the output is behaviour or speech. The Central Processing Unit (CPU) the brain encodes information into a suitable format for process or storage. 9

10 However, as the brain can first the analogy is really the wrong way round, computers are trying to be like human brains! That is the rationale behind Artificial Intelligence (AI) Computer analogies have been criticized for machine reductionism, which means that they reduce complex thought processes down to simple mechanical processes. Schema theory Simply put, schema theory states that all knowledge is organized into units. Within these units of knowledge, or schemata, is stored information. A schema, then, is a generalized description or a conceptual system for understanding knowledge-how knowledge is represented and how it is used. Piaget emphasized the importance of schemas in cognitive development, and described how they were developed or acquired. A schema can be defined as a set of linked mental representations of the world, which we use both to understand and to respond to situations. Bartlett s War of the Ghost Study Bartlett s hypothesis was that memory is reconstructive and that people store and retrieve information according to expectations formed by cultural schemas. He told participants an unfamiliar story that was part of Native American Folklore. 10

11 One night two young men from Egulac went down to the river to hunt seals and while they were there it became foggy and calm. Then they heard war-cries, and they thought: "Maybe this is a war-party". They escaped to the shore, and hid behind a log. Now canoes came up, and they heard the noise of paddles, and saw one canoe coming up to them. There were five men in the canoe, and they said: "What do you think? We wish to take you along. We are going up the river to make war on the people." One of the young men said,"i have no arrows." "Arrows are in the canoe," they said. "I will not go along. I might be killed. My relatives do not know where I have gone. But you," he said, turning to the other, "may go with them." So one of the young men went, but the other returned home. And the warriors went on up the river to a town on the other side of Kalama. The people came down to the water and they began to fight, and many were killed. But presently the young man heard one of the warriors say, "Quick, let us go home: that Indian has been hit." Now he thought: "Oh, they are ghosts." He did not feel sick, but they said he had been shot. So the canoes went back to Egulac and the young man went ashore to his house and made a fire. And he told everybody and said: "Behold I accompanied the ghosts, and we went to fight. Many of our fellows were killed, and many of those who attacked us were killed. They said I was hit, and I did not feel sick." He told it all, and then he became quiet. When the sun rose he fell down. Something black came out of his mouth. His face became contorted. The people jumped up and cried. He was dead. Bartlett found that participants changed the story as they tried to remember it - a process called distortion. Bartlett found that there were three patterns of distortion that took place. Assimilation: The story became more consistent with the participants own cultural expectations - that is, details were unconsciously changed to fit the norms of British culture. Levelling: The story also became shorter with each retelling as participants omitted information that was seen as not important. Sharpening: Participants also tended to change the order of the story in order to make sense of it using terms more familiar to the culture of the participants. They also added detail and/or emotions. The participants overall remembered the main themes in the story but changed the unfamiliar elements to match their own cultural expectations so that the story remained a coherent whole although changed. 11

12 Task: - Make notes on the schema activity we have just done in class Task: - Make notes on the strengths and weaknesses of schema theory Strengths Weaknesses 12

13 Cognitive Neuroscience Advances in cognitive neuroscience mean that we can now see what areas of the brain are involved in specific cognitive functions. These techniques allow us to accurately map the function of the brain. Before these advances we had to rely on case studies of brain damaged individuals, these were unsatisfactory as data from before the damage was rarely available and these individuals were atypical. Cognitive neuroscience allows us to study healthy brains. fmri Functional Magnetic Resonance Imaging PET Positron Emission Tomography 13

14 Brainbows These techniques give us a unique insight into the functionality of the brain. For example, we now know that Broca s area is very important for speech, any damage to this area serious impairs speech. Task: - Evaluate Cognitive Neuroscience Strengths Weaknesses 14

15 5) Biological Approach This approach, as the name suggests, focuses on biological explanations of human behaviour. Of particular importance are the influences of genes, biological structures, neurochemistry and evolution. The biological approach is firmly on the nature side of the nature/nurture debate. It is often criticized as being reductionist as it ignores social and cultural influences on behaviour. Genetic inheritance Our genetic inheritance comes from our parents we have 50% of our mother s genes and 50% of our father s genes. This explains why we may share both physical and psychological characteristics with our parents. However, although genes contain the blueprint for particular characteristics, how they develop or are expressed in a particular individual depends on the complex interaction between nature and nurture. One way psychologists study this interaction is through twin studies. Monozygotic (MZ) or identical twins share 100% of each other s genes, whilst Dizygotic (DZ) or non-identical twins only share 50%, the same as siblings. Psychologists look at concordance rates, these are the percentage of both twins displaying the same characteristics, and the expectation is that if a characteristic is inherited there will be a higher concordance rate in MZ twins. For example, Gottesman and Shields (1972) found a 58% concordance rate for Schizophrenia in MZ twins compared to a 12% concordance rate with for DZ twins. Task: - What concordance rate would you expect if a characteristic was wholly inherited? What other factors do we need to consider? 15

16 Genotype and Phenotype The genotype is the genetic code written into the DNA of individual cells, the phenotype is physical appearance of that in the individual. In most cases, the two things will coincide, but, not always! For example, eye colour is obviously inherited from parents. But, if a child inherits recessive blue eye gene from one parent this will not be expressed if they inherit a dominant brown eye gene from the other parent. In this case the genotype (blue eye recessive, brown eye dominant) cannot be observed from the phenotype (brown eyes). Illness or disease can also affect the phenotype, especially prenatally or at birth. Biological Structures We will look at the brain and nervous system in more detail later in the course. In a nutshell: - The nervous system has two major systems: - The Central Nervous System (CNS) Brain and spinal cord The Peripheral Nervous System (PNS) somatic and autonomic nervous systems. The nervous system sends messages from one part of our bodies to another using nerve cell, known as neurons. These transmit impulses in the form of electrical signals. 16

17 The Brain The largest part of the brain is the Cerebrum making up about 85% of its total mass. The Cerebellum, which is Latin for little brain, controls are automatic functions such as breathing etc. Higher cognitive functions take place in the Cerebrum. The frontal lobe is involved with speech, though and learning, the temporal lobes with hearing and memory, the parietal lobes, sensory information such as touch, taste and pain and the occipital lobe visual information. Neurotransmitters When an electrical nerve impulse reaches the end of a neuron, a chemical known as a neurotransmitter is released. These neurotransmitters travel across the junctions of neurons which are known as synapses. The levels of these neurotransmitters can affect mood and behaviour in individuals. For example, the dopamine hypothesis in schizophrenia suggests that schizophrenia results from an excess of dopamine. This causes the neurons to fire more often and transmits too many messages. These messages overload may produce many of the symptoms of schizophrenia. A more recent explanation suggests that individuals may have too many dopamine receptors, rather than too much dopamine, but the end result is the same. Hormones Hormones are chemicals produced by the endocrine glands. These too can affect behaviour. Task: - Give an example. 17

18 Evolutionary theory Darwin Darwin suggests that organisms become adapted over time to their environment by a process known as natural selection. action! A good example here is the peppered moth, before the industrial revolution peppered moths were much lighter in colour. Due to industrial pollution the lighter coloured moths were easier for predators to see. Therefore, it was the darker moths, those that blended in with the pollution, that survived to reproduce and their genes carried. Therefore today peppered moths are much darker in colour. Survival of the fittest in Task: - How would you explain the giraffe s neck using the principles of evolutionary theory? Bowlby argues that attachment to a primary caregiver has evolved because it gives the infant a survival advantage. Buss argues that mate choices have evolved because they lead to reproductive success. So women desire males with resources, because they will able to provide for them and their offspring and men prefer young, physically attractive women as it indicates fertility. Evaluation This theory runs into trouble when we try and explain why not all organisms have evolved at the same rate. For example, some believe we evolved from the apes, but that begs the question of why apes still exist! 18

19 Task: - Make notes under each of the evaluation headings. Strengths The importance of the scientific method Weaknesses Reductionism Practical Applications Issues with evolutionary theory 19

20 Exam Questions (AS Level) 1) Complete the following sentence. Shade one box only. Sensory neurons carry information A away from the brain B both to and from the brain C towards the brain D within the brain [1 mark] 2) Complete the following sentence. Shade one box only. The somatic nervous system A comprises of two sub-systems B connects the central nervous system and the senses C consists of the brain and spinal cord D controls involuntary responses. [1 mark] 3) Which one of the following responses results from the action of the sympathetic division of the autonomic nervous system? Shade one box only. A Decreased pupil size B Increased digestion C Increased heart rate D Increased salivation [1 mark] 20

21 4) Label the two areas of the synapse in Figure 1 by putting the appropriate letter in each box. A Axon B Dendrites C Neurotransmitters D Receptor sites E Vesicle Figure 1: The synapse [2 marks] 5) Read the item and then answer the question that follows. Psychologists investigating theoretical models of cognitive processing study human cognitive processing. They sometimes give participants problems to solve then ask them about the experience afterwards. Typical participant responses are as follows: Response A: There were too many things to think about at the same time. Response B: I had to do one task at a time, then do the next task, 21

22 and so on. Briefly suggest how each of these responses might inform psychologists investigating models of human cognitive processing. [2 marks] 6) Read the item and then answer the question that follows. A behaviourist researcher studying reinforcement carried out a laboratory experiment. He put a cat in a puzzle box. The cat was able to escape from the puzzle box by pulling on a string which opened the door. Each time the cat escaped it was given a food treat. At first, the cat escaped quite slowly, but with each attempt the escape time decreased. Explain which type of conditioning is being investigated in this experiment? [2 marks] 22

23 7) Read the item and then answer the questions that follow. The data from the laboratory experiment are shown in Table 1. Table 1: Time taken for the cat to escape from the puzzle box Attempt Time taken for the cat to escape from the puzzle box (seconds) Calculate the mean time taken for the cat to escape from the puzzle box. Show your calculations. [2 marks] 23

24 8) The researcher compared the time taken for the cat to escape at the first attempt, with the time taken for the eighth attempt. He found that after learning had taken place the cat s escape time was: Shade one box only. A 9 times faster than it was at the start. B 11times faster than it was at the start. C 15 times faster than it was at the start. D 21 times faster than it was at the start. [1 mark] 9) Read the item and then answer the questions that follow. A psychologist carried out a study of social learning. As part of the procedure, he showed children aged 4-5 years a film of a 4 year-old boy stroking a puppy. Whilst the children watched the film, the psychologist commented on how kind the boy was. After the children had watched the film, the psychologist brought a puppy into the room and watched to see how the children behaved with the puppy. Outline what is meant by social learning theory and explain how social learning might have occurred in the procedure described above. [6 marks] 10) Discuss two limitations of social learning theory. [6 marks] 24 marks total 24