Unit 3 Area of Study 2

1. Unit 3 Area of Study 2 How do people learn and remember?

2. Part 1 - Neural Basis of Learning and Memory • Dot point 1 - neural plasticity and changes to connections between neurons (including long-term potentiation and long-term depression) as the fundamental mechanisms of memory formation that leads to learning

3. Neural Plasticity Neural Plasticity • Learning and memory both require the brain to change its structure and functioning to incorporate the new information. • Learning cannot occur without memory. If we had no memory of events and information, every experience would feel like it was brand new. Every person encountered would need to be introduced, even if you had met them thousands of times. Getting dressed, making a meal, reading, writing and all of the other daily tasks we undertake would need to be relearnt each time and there would be no time for anything else in life. • It is our memory that allows us to store information for later use, so that we can complete all of those tasks that we don’t even need to think about, once learned. When we learn, we create a memory and the learning and memory processes create changes to the brain. • The brain’s ability to change is known as neural plasticity.

4. Neural Plasticity • Neural plasticity:the ability of the brain’s neural structure or function to be changed by experience throughout the lifespan. • Plasticity refers to the flexibility of the brain. Before we are born, our brain is developing and changing and this continues for the whole of our lives. Plasticity is at its most flexible during childhood, when the most learning is experienced. During childhood the brain is also still growing, as new neurons are being created, and an individual has both developmental and adaptive plasticity at work. • There are two types of plasticity: • developmental plasticity • adaptive plasticity • Developmental plasticity is the growth of the nervous system and brain. It begins before we are born and finishes in our early twenties when the brain is fully formed. • Adaptive plasticity occurs across the lifespan. It is the brain’s ability to change in response to damage or experience (learning).

5. Neural Plasticity • As we age, the plasticity of the brain reduces, but changes are still possible. The brain is fully formed (has all of its neurons) in a person’s early twenties, and this leaves them with only adaptive plasticity. We can still make changes to our brain structure and function, but it takes more effort. For example: we can learn a new language, a new sport, a musical instrument, but not as quickly as a child would. • Neural plasticity can occur by one of three mechanisms: • By modifying the strength or effectiveness of synaptic transmission of existing synaptic connections • By producing growth of new synaptic connections or the pruning away of existing ones • By modulating the excitability properties of individual neurons

6. Changes to connections between neurons • When neurons communicate with each other, they do this by sending neurotransmitters across the synapse. • Three components to the synapse. • The synaptic gap: the tiny space between the axon (presynaptic neuron) and the dendrite (postsynaptic neuron) • Axon ending (Axon Terminal): Presynaptic neuron ‘sending’ the message or neural impulse • Dendrite: Postsynaptic neuron ‘receiving’ the message or neural impulse • Synaptic formation occurs when neurotransmitters are released across the synapse and dendrites grow new branches and lengthen in response. When pathways are not used the dendrites are pruned. • When neurons connect with each other, the pre-synaptic neuron releases neurotransmitters. The neurotransmitters flood into the synapse and are absorbed at the receptor sites of the dendrites in the post-synaptic neuron. With each use of the neural connection (neural pathway), the pre-synaptic neuron and post-synaptic neuron are activated at the same time and this strengthens the connection. • Hebb: “neurons that fire together, wire together” • Neurons that activate at the same time strengthen neural pathways and connections. Neurons not activated (perhaps through disuse) weaken connections.

7. Long-term potentiation and long-term depression • When learning something new, we practice the skill, information, etc. and this creates the memory (neural pathway). The more we practice, the stronger the connection between neurons. This strengthening of neural connections is known as long-term potentiation (LTP). • Long-term potentiation (LTP):The long-lasting strengthening of the synaptic connections of neurons, resulting in enhanced functioning or more effective synaptic transmission. • LTP improves the ability of the presynaptic and postsynaptic neurons to communicate with one another at the synapse. • LTP is crucial to learning, as is the hippocampus • Hippocampus is crucial to learning and memory and therefore LTP. • NMDA is a neurotransmitter receptor on the dendrite (found mostly around the hippocampus). It receives the neurotransmitter ‘glutamate’ and has an important role in LTP.

8. Long-term potentiation and long-term depression • Long-term depression: is a long-lasting decrease in the strength of synaptic transmission. • Long-term depression is the opposite of long-term potentiation. The pre-synaptic and post-synaptic neurons are not stimulated to communicate. This lack of ‘firing’ of the neurons, slows down synaptic transmission and makes the post-synaptic neurons less responsive to neurotransmitters released by the pre-synaptic neurons. • Long-term depression is important for learning and memory as it assists in synaptic pruning. Synaptic connections that are unimportant and not used frequently are cut off. This allows the neurons to make or strengthen other neural pathways. This can assist us in changing the way we think, by correcting errors in memories and skills. The changes are kept and the errors are pruned. • Each neuron in the brain can have thousands of neural connections. • Long-term potentiation and long-term depression both contribute to the philosophy of ‘use it or lose it.’

9. Part 1 - Neural basis of learning and memory • Dot point 2 - the role of neurotransmitters and neurohormones in the neural basis of memory and learning (including the role of glutamate in synaptic plasticity and the role of adrenaline in the consolidation of emotionally arousing experiences).

10. Neurotransmitters and Neurohormones • Neurotransmitters:chemicals released into the synapse as part of neural transmission. • Neurohormones:chemicals released from the axon terminals of a neuron into the bloodstream via capillaries (tiny blood vessels). • Hormones:chemicals released into the bloodstream from glands. • Neurohormones are not as fast-acting as neurotransmitters as they travelled a greater distance to communicate with other cells. • Neurohormones, like neurotransmitters, will only interact with other cells that have specialised receptor sites to receive them.

11. Neurotransmitters and Neurohormones

12. Neurotransmitters and Neurohormones • The hypothalamus has neurons that produce different kinds of neurohormones. • For example: the HPA axis. During pro-longed arousal (long-term stress) the hypothalamus releases the neurohormone TRH. TRH travels to the pituitary gland and signals the pituitary gland to produce ACTH which enters the bloodstream to travel to the adrenal cortex to stimulate the release of cortisol. • The neurotransmitter glutamate has a crucial role in learning and synaptic plasticity. • The hormone adrenaline has a crucial role in consolidation of emotional memories.

13. Glutamate and Synaptic Plasticity • Synaptic plasticity refers to the changes that occur to the synaptic connections between two or more neurons. • When learning is taking place, changes occur at the synapse, to create or strengthen the neural pathway. • The neural pathways form the ‘memory trace’ which is the physical changes to the brain that occur when new information is stored in long-term memory. • Glutamate is an excitatory neurotransmitter. It stimulates neurons to fire, thus strengthening the pathways each time they are used (as in LTP). • For glutamate to be effective, there must be receptor sites to absorb the glutamate. Two such receptor sites are NMDA and AMPA. • These two receptor sites on post-synaptic neurons accept the glutamate and the neural message continues to be transmitted along the neural pathway. • Each time glutamate is released by the pre-synaptic neuron, its excitatory effect is increased creating more NMDA and AMPA receptor sites on the post-synaptic neuron. This process also stimulates dendritic growth, creating more receptor sites. These changes to the neuron strengthen the neural pathway (LTP) allowing the memory of the learning to form. The more the pathway is used (practice) the easier the information is to retrieve.

14. Adrenaline and the consolidation of emotionally arousing experiences • Adrenaline has a major role in the consolidation and storage of emotional memories. Emotions that produce adrenaline have an effect on the strength of a newly forming memory. • Adrenaline can be both a neurohormone and a neurotransmitter. When the fight-flight response is activated, adrenaline is released into the bloodstream and is a neurohormone. • During the fight-flight response, adrenaline can also be released from neurons in the brain, making it a neurotransmitter. • In the brain, when adrenaline is secreted it effects the functioning of the amygdala, by inducing the release of noradrenaline within the amygdala.

15. Adrenaline and the consolidation of emotionally arousing experiences • Amygdala:structure located within the medial temporal lobe of the brain and has a crucial role in processing emotions (fear responses) and implicit learning. • When emotions cause arousal, the amygdala signals the hippocampus that the memory is important and needs to be strengthened. • Hippocampus:structure located within the medial temporal lobe of the brain and has a crucial role in the consolidation of most of our memories (declarative memories). • Emotionally arousing events are strengthened in our memory as a survival mechanism. It is important to remember dangerous situations to identify them and avoid them in the future. • This process can have detrimental effects in cases such as phobia and PTSD. • Phobia: When the person comes into contact with the phobic stimulus, for example a spider, it activates the fight-flight response. The adrenaline triggers the amygdala as well as the hippocampus so that the emotion can be attached to the memory when it is stored. The next time the phobic stimulus (spider) is encountered, fear is remembered and the spider is avoided (link to Unit 4)

16. Peer Marking Carousel

17. Distinguish between long-term potentiation and long-term depression (2 marks) • Georgina has suffered a brain injury and cannot move her right arm even though the arm is undamaged. Her physiotherapist has arranged for Georgina to use a therapy machine that exercises her arm by moving it up and down for 30 minutes each day. The physiotherapist has also advised Georgina to think about moving her arm while she is using the machine. • In terms of brain plasticity, explain why the physiotherapist advised Georgina to think about moving her arm while using the machine (3 marks)

18. An experiment found that rats remembered the place in an apparatus where they received electric shocks to a foot for much longer and better that did not receive shocks. Explain this finding with reference to the role of adrenaline in the consolidation of emotionally arousing experiences (6 marks). • Describe the roles of the neuron and neurotransmitter as mechanisms of learning and memory (2 marks)

19. Part 2 - Models to Explain Learning • Dot point 1 - classical conditioning as a three-phase process (before conditioning, during conditioning and after conditioning) that results in the involuntary association between a neutral stimulus and unconditioned stimulus to produce a conditioned response, including stimulus generalisation, stimulus discrimination, extinction and spontaneous recovery

20. Classical Conditioning • Classical conditioning, studied by Pavlov, occurs when a neutral stimulus (NS) is associated with an unconditioned stimulus (UCS) to elicit a response. • The UCS causes a reflex response called the unconditioned response (UCR). If the NS is consistently paired with the UCS, it becomes a conditioned stimulus (CS) capable of producing a response by itself. This response is a conditioned (learnt) response (CR). • When the CS is followed by the UCS, conditioning is reinforced (strengthened). • When the CS is repeatedly presented alone, conditioning is extinguished (weakened or inhibited). After extinction seems to be complete, a rest period may e followed by the temporary reappearance of a CR. This is called spontaneous recovery. • Though stimulus generalisation, stimuli similar to the CS will also produce the CR. Generalisation gives way to stimulus discrimination when an organism demonstrates the CR only when the specific CS is present.

21. Classical Conditioning • Stimulus: any event that elicits (produces) a response from an organism. • Response: a reaction by an organism to a stimulus. • UCS: any stimulus that consistently produces an UCR. • UCR:the response that occurs automatically as a result of the UCS. • CS:the stimulus that is neutral at the start of classical conditioning and does not normally produce the UCR, but eventually becomes associated with the UCS. • CR:the learned or acquired response to the CS.

22. Classical Conditioning Three-phase model: • 1. Before conditioning: • NS is presented and does not elicit a relevant response. • UCS is presented and elicits the UCR. • 2. During conditioning: • NS (which becomes the CS) is paired with the UCS. The UCS is presented as soon after the CS as possible and the UCR is elicited. • The CS and UCS are paired over a number of trials for the learning(conditioning) to be acquired. This creates the CR. • 3. After conditioning: • CS is presented and elicits the CR • Example: Pavlov’s experiment with the dogs

23. Classical Conditioning

24. Key Processes in Classical Conditioning • Acquisition: is the overall process during which an organism learns to associate two events (the CS and UCS). The CS and UCS are presented closely together and the duration of acquisition is the number of trials it takes for the CR to be acquired. • Extinction: the gradual decrease in the strength or rate of a CR that occurs when the UCS is no longer presented. When a CR no longer follows presentation of the CS. • Spontaneous recovery:is the reappearance of a CR when the CS is presented, following a rest period, after the CR appears to have been extinguished. • Stimulus generalisation:the tendency for another stimulus – one that is similar to the original CS – to produce a response that is similar to the CR. • Stimulus discrimination:Occurs when a person or animal responds to the CS only, but not to any other stimulus that is similar to the CS.

25. Key terms = definitions Command terms = common structure How? What? When? Where? Why? Using the dot point to predict questions Dot point 1 - classical conditioning as a three-phase process (before conditioning, during conditioning and after conditioning) that results in the involuntary association between a neutral stimulus and unconditioned stimulus to produce a conditioned response, including stimulus generalisation, stimulus discrimination, extinction and spontaneous recovery

26. Part 2 - Models to Explain Learning • Dot point 2 - operant conditioning as a three-phase model (antecedent, behaviour, consequence) involving reinforcers (positive and negative) and punishment (including response cost) that can be used to change voluntary behaviours, including stimulus generalisation, stimulus discrimination and spontaneous recovery (excluding schedules of reinforcement)

27. Operant Conditioning • Operant conditioning is a learning process in which the likelihood of a behaviour being repeated is determined by the consequences of that behaviour. • Operant:a response (or set of responses) that occurs and acts (operates) on the environment to produce some kind of effect. • Operant Conditioning is based on Thorndike’s Law of Effect. An organism will tend to repeat a behaviour (operant) that has desirable consequences, or that will enable it to avoid undesirable consequences. • Organisms will tend to not repeat a behaviour that has an undesirable consequence. • Operant Conditioning is also known as ‘Instrumental Learning’. • Instrumental learning: refers to the process through which an organism learns the association between behaviours and its consequences.

28. Operant Conditioning B.F. Skinner • An American behavioural psychologist. Skinner’s work into operant conditioning was pivotal in determining what we know about such techniques today. Some of his reinforcement techniques included teaching pigeons how to dance, play ping-pong and bowl a ball in a mini bowling alley. • Skinner created an apparatus for studying operant conditioning. This conditioning chamber is known as the ‘Skinner box’. Skinner conducted many experiments with the Skinner box, most notably with rats. • Hungry rats were placed in the box and learnt to press a lever to receive food.

29. Three-Phase Model of Operant Conditioning 1. The Antecedent Stimulus precedes an operant (A) 2. The Behaviour that occurs in response to the antecedent (B) 3. The Consequence to the behaviour (C) • Antecedent (A) --> Behaviour (B) --> Consequence (C)

30. Principles of Operant Conditioning • Acquisition: the establishment of a response through reinforcement. • Extinction:the gradual decrease in the strength or rate of a conditioned (learned) response following a consistent non-reinforcement of the response. • Spontaneous recovery:after extinction, the response can be shown in the absence of any reinforcement. • Stimulus generalisation: occurs when the correct response is made to another stimulus that is similar (but not necessarily identical) to the stimulus that was present when the conditioned response was reinforced. • Stimulus discrimination:occurs when an organism makes the correct response to a stimulus and is reinforced, but does not respond to any other stimulus, even when stimuli are similar (but not identical). Organisms will differentiate between stimuli that signal reinforcement and non-reinforcement.

31. Principles of Operant Conditioning • The most effective way for people to learn is through reinforcement. Reinforcement is used when we want desirable behaviours to be repeated. • Reinforcement:occurs when a stimulus strengthens the likelihood of a response that it follows. • Reinforcer: can also be known as a reward. • Continuous reinforcement: the reinforcer is provided immediately after every correct response. • Continuous reinforcement is used when a person or animal is learning the behaviour (during acquisition). • Partial reinforcement: the process of reinforcing some correct responses, but not all of them. • Partial reinforcement is used once the behaviour is learnt to strengthen and maintain the learning.

32. Types of Reinforcement and Punishment • Positive reinforcement: a stimulus that strengthens or increases the frequency or likelihood of a desired response by providing a satisfying consequence (reward). • Negative reinforcement:The removal or avoidance of an unpleasant stimulus. It increases the likelihood of a response being repeated and thereby strengthening the response. • Punishment:the delivery of an unpleasant consequence following a response, or the removal of a pleasant consequence following a response. • There are two types of punishment: positive punishment and negative punishment (response cost). • Positive punishment: involves the presentation or introduction of a stimulus that decreases the likelihood of a response occurring again (giving something). • Negative punishment:involves the removal of a stimulus and thereby decreasing the likelihood of a response occurring again (taking something away). • Response cost:described as involving any valued stimulus being removed whether it causes the behaviour or not.

33. Operant Conditioning

34. Operant Conditioning

35. Operant Conditioning Factors that affect the effectiveness of reinforcement and punishment: • 1. Order of presentation: • Reinforcement and punishment must be presented after the response has occurred. • 2. Timing: • Reinforcement and punishment are most effective when they occur immediately after the response. • 3. Appropriateness: • For any stimulus to be a reinforcer, it must provide a pleasing or satisfying consequence for its recipient. • For any stimulus to be a punisher, it must provide a consequence that is unpleasant and therefore likely to decrease the likelihood of undesirable behaviour. An inappropriate punishment may have the opposite effect and act as a reinforcer.

36. Key terms = definitions Command terms = common structure How? What? When? Where? Why? Using the dot points to predict questions Dot point 2 - operant conditioning as a three-phase model (antecedent, behaviour, consequence) involving reinforcers (positive and negative) and punishment (including response cost) that can be used to change voluntary behaviours, including stimulus generalisation, stimulus discrimination and spontaneous recovery (excluding schedules of reinforcement)

37. Part 2 - Models to Explain Learning • Dot point 3 - observational learning as a method of social learning, particularly in children, involving attention, retention, reproduction, motivation and reinforcement

38. Observational Learning • Observational Learning: occurs when someone uses observation of another person’s actions and their consequences to guide their future actions. Also known as ‘Modelling’ or ‘Social Learning’. • Observational learning is influenced by the personal characteristics of the model and the success or failure of the model’s behaviour. Studies have shown that aggression is readily learnt by modelling. • Learning complex behaviours through observation can be a lot more efficient than learning through trial and error, or waiting until reinforcement or punishment is given. • Both classical and operant conditioning can occur vicariously through observational learning. Vicarious reinforcement and vicarious punishment are used to condition the response in vicarious conditioning.

39. Observational Learning • Vicarious conditioning:When an individual observe a model displaying behaviour that is either reinforced or punished and later behaves in the same way, in a modified way or refrains from doing so as a result of the observation. • Vicarious reinforcement: when an individual observes a model displaying behaviour that is reinforced, which has the effect of increasing the likelihood of the observer performing that behaviour in a modified or identical way. • Vicarious punishment: when an individual observes a model displaying behaviour that is punished, which has the effect of reducing the likelihood of the observer performing that behaviour in a modified or identical way. • By observing a model, a person may learn: • new responses • to carry out or avoid previously learnt responses • a general rule that can be applied to various situations

40. Observational Learning • For observational learning to occur, several factors must be involved: 1. Attention:The learner must pay attention to the model; the learner must perceive the model to be interesting in one way or another 2. Retention:The learner must remember (retain) what was done by the model so that the information can be encoded and stored for later use. 3. Reproduction:The learner must be able to reproduce (form a reproduction, or copy, of) the modelled behaviour. 4. Motivation:The learner must have the desire, or motivation, to repeat the observed behaviour. 5. Reinforcement:The behaviour must be useful or provide an incentive or reward for the learner to learn and continue to perform the behaviour. Reinforcement is required. • *If the modelled behaviour is reinforced, the learner is motivated to repeat the behaviour.

41. Bandura’s Bobo Doll Experiments • Albert Bandura conducted experiments in the 1960’s to investigate observational learning with young children. • Pre-school aged children were required to sit and watch a video of a model, an adult, behaving aggressively (punching, hitting and kicking the BoBo Doll). • There were three conditions (three different versions of the video) in the experiment. • Condition 1: children watched the video of the model punching, hitting and kicking the BoBo Doll. The model was then rewarded with lollies, soft drink and praise by another adult. • Condition 2: children watched the video of the model punching, hitting and kicking the BoBo Doll. The model was punished with a spanking and verbal criticism. • Condition 3: children watched the video of the model punching, hitting and kicking the BoBo Doll. There were no consequences for the model’s behaviour. No reinforcement or punishment were administered. • After watching the video, the children were placed individually in a room with various toys and the BoBo Doll. Some of the children received rewards (fruit juice, stickers and praise) for aggressive behaviour, whilst others did not.

42. Bandura’s Bobo Doll Experiments Results of the experiment • Overall, boys were more aggressive than girls. However, girls were nearly as aggressive as the boys when offered a reward. • Condition 1: Boys and girls had almost identical levels of aggression when they were rewarded. When not rewarded, boys were more aggressive than girls. • Condition 2: Boys and girls had similar levels of aggression (boys higher) when rewarded. Without rewards, aggression levels were lower and significantly lower for girls. • Condition 3: Boys and girls had high levels of aggression when rewarded. The aggression levels dropped without the reward, but were slightly higher than those of condition 1.

43. Bandura’s Bobo Doll Experiments

44. Bandura’s Bobo Doll Experiments Conclusions • Whilst individuals may make no observable response to a behaviour performed by a model, the acquisition of the modelled response in cognitive form has still occurred and can be elicited with an appropriate reinforcer. • When observers pay attention, they make cognitive representations (mental codes or images) of what they observe. • People learn by observation not only how to acquire or modify behaviour, but also about what behaviours can be expected to lead to particular consequences.

45. Exam Question Practise • Short answer technique: • Underline instructions/command words • Look at mark allocation • Re-check answer

48. Part 2 - Models to Explain Learning • Dot point 4 - the ‘Little Albert’ experiment as illustrating how classical conditioning can be used to condition an emotional response, including ethical implications of the experiment.

49. Classical Conditioning - Little Albert Conditioned Emotional Responses • An emotional reaction that usually occurs when the autonomic nervous system produces a response to a stimulus that did not previously trigger that response. Little Albert – conditioned fear response • Watson and Rayner (1920) conditioned a fear response in an 11-month old baby named Albert. • Three phase process of Classical Conditioning: • 1. Before Conditioning: • Watson and Raynor tested Albert to make sure he did not already have a fear response. They did this by presenting to him a series of animals, including the white rat. • The white rat (NS) did not produce a relevant response. • 2. During Conditioning: • Watson repeatedly paired the white rat (NS) with a loud, scary noise (UCS) created by hitting a hammer on a steel pipe behind Albert’s head. This noise produced fear (UCR). • It only took seven trials for the conditioning to be learnt. • 3. After Conditioning: • Whenever Albert was presented with the white rat (CS), he would produce a fear response (CR) and try to get away. • Watson and Raynor also noted that stimulus generalisation occurred. Albert showed the fear response (CR) when presented with any stimuli that was white or furry which was similar to the white rat (CS). NS = White rat UCS = Loud, scary noise UCR = Fear in response to loud, scary noise CS = White rat CR = Fear in response to white ra

50. Classical Conditioning - Little Albert • NS = White rat • UCS = Loud, scary noise • UCR = Fear in response to loud, scary noise • CS = White rat • CR = Fear in response to white rat • There are a number of reasons why Watson and Rayner’s experiment is now considered unethical: • The experiment was designed to condition an emotional response of fear in the participant. It could therefore reasonably be assumed that the participant would be emotionally traumatised by the experiment, and that he may have suffered lasting psychological harm as a result. • Watson failed to seek permission from Albert’s mother; therefore, no informed consent was obtained and withdrawal rights were not explained. • Watson did not debrief either Albert or his mother, to extinguish the conditioned fear response, and though no one is sure what became of Little Albert, he was probably left with an irrational fear of anything white and fluffy. • Watson failed to follow the ethical principles of confidentiality. He published results of his experiment without ensuring that Little Albert would remain anonymous.