Unit 3 Area of Study 2 How do

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

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

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.

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).

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

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 presynaptic 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

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.

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 presynaptic 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. ’

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).

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.

Neurotransmitters and Neurohormones Neurotransmitters Neurohormones Chemicals released by a presynaptic neuron Released directly into the synapse Released directly into the bloodstream Can only affect neurons that are directly linked via the synapse Carry messages throughout the body so can affect target cells in specific organs at distant sites Carry messages from a pre-synaptic Carry messages from axon terminals neuron to a post-synaptic neuron of neurons to glands in the body Travel short distances Can travel longer distances than neurotransmitters Effect is quick Effect is not as quick as neurotransmitters

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 travels to the pituitary gland 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.

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.

Adrenaline and the consolidation of emotionally Adrenaline has a major role in the consolidation and storage arousing experiences 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.

Adrenaline and the consolidation of emotionally Amygdala: structure located within the medial temporal lobe of the brain and has arousing experiences 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)

Peer Marking Carousel

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)

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)

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

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

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: 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.

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

Classical Conditioning

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.

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 Key terms = definitions Command terms = common structure How? What? When? Where? Why?

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)

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.

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 pingpong 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.

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)

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.

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.

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.

Operant Conditioning Giving something Taking away Positive Reinforcer Negative Reinforcer Positive Punishment Negative Punishment (Response cost)

Operant Conditioning

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.

Using the dot points to Dot point predict 2 - operant questions conditioning as a three-phase Key terms = 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 definitions Command terms = common structure How? What? When? Where? Why?

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

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.

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

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.

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 Bo. Bo 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 Bo. Bo 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 Bo. Bo 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 Bo. Bo 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 Bo. Bo Doll. Some of the children received rewards (fruit juice, stickers and praise) for aggressive behaviour, whilst others did not.

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.

Bandura’s Bobo Doll Experiments

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.

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

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.

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 d 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

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 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.

Using the dot point to predict the question Dot point 4 - the ‘Little Key terms = Albert’ experiment as illustrating how classical conditioning can be used to condition an emotional response, including ethical implications of the experiment. definitions Command terms = common structure How? What? When? Where? Why?

Part 3 - Process of Memory Dot point 1 - the multi-store model of memory (Atkinson-Shiffrin) with reference to the function, capacity and duration of sensory, short-term and long-term memory.

Memory - The storage and retrieval of information acquired through learning. Memory consists of three key components: encoding, storage and retrieval. 1. Encoding – the process of converting information into a useable form or ‘code’, so that it can enter and be stored in memory. Two types of encoding: automatic and effortful Automatic – information that is encoded without deliberate mental effort. Usually information about a person’s location in space and time. Effortful – deliberate, mental effort is required to retain specific information. 2. Storage – the retention of information over time. 3. Retrieval – the process of locating and recovering the stored information from memory.

Multi-store Model of Memory Atkinson and Shiffrin proposed a model of memory that identifies three different levels of memory. 3 distinguishable components called the sensory register, short-term store and long-term store. Information is held and processed in each and information passes through each. Each system encodes, stores and processes information in different ways. The systems operate simultaneously and interact.

Multi-store Model of Memory Type of memory Duration Capacity Function Sensory memory 0. 3 -4 seconds Unlimited Acts as a filter for all incoming sensory information. Information attended to will transfer to STM. Rapid decay of sensory information allows for perception of the world to be smooth and ongoing. Sensory – Iconic 0. 3 seconds Unlimited Stores and filters visual information. Sensory – Echoic 3 -4 seconds Unlimited Stores and filters auditory information. Short-term memory (STM) 12 -20 seconds. Up to 30 seconds if rehearsed. 5 -9 pieces of information (7± 2) AKA: Working memory Information is transferred from Sensory Memory and retrieved from LTM to be manipulated and used at a particular moment in time (in our conscious awareness). Transfers information to LTM. Long-term memory (LTM) Relatively permanent Unlimited Storage for information that has passed through Sensory Memory and STM, to be retrieved and used at a later time.

Multi-Store Model of Memory 1. Sensory Memory Entry point of memory where new incoming sensory information is stored for a very brief period of time. Sensory memory is made up of different sensory registers. One for each of the senses. Information is stored as an exact copy of the original. Duration: 0. 2 seconds up to 4 seconds. Capacity: unlimited When information is attended to it is transferred to STM and we become consciously aware of it and encode it for permanent storage. If not attended to the information is lost very quickly and cannot be stored permanently. Two sensory registers: iconic and echoic. Iconic Memory: Visual sensory memory that stores visual images in their original sensory form for between 0. 2 and 0. 4 seconds. Capacity: unlimited Duration: 0. 2 -0. 4 seconds

Multi-Store Model of Memory Echoic Memory Auditory sensory memory that stores sounds in their original sensory form for up to 3 or 4 seconds. Capacity: unlimited Duration: 3 -4 seconds All sounds 3 -4 seconds allows for attention to switch to sounds and transfer information to STM Individual sounds are processed. Parts of speech are heard separately and must be stored long enough for the whole word to be put together to create meaning.

Multi-Store Model of Memory 2. Short Term Memory (STM) A memory system with limited storage capacity in which information is stored for a limited time (relatively short period of time) unless renewed in some way. Capacity: 7 ± 2 pieces of information (5 -9 pieces) Duration: 12 -30 seconds Methods to increase STM: Chunking - The grouping of separate bits of information into larger ‘chunks’. Rehearsal - Information can be kept longer in STM if rehearsal is used. Rehearsal is the process of consciously manipulating information to keep it in STM, to transfer it to LTM or aid storage and retrieval. Two types of rehearsal: maintenance and elaborative Maintenance Rehearsal: rote learning, repetitive and keeps information in STM, does not assist encoding for storage in LTM. Information kept in STM through maintenance rehearsal restricts the amount of new information that can enter STM. Elaborative Rehearsal: linking new information in a meaningful way with other new information or information already stored in LTM. Elaborative rehearsal is a more active and effortful process than maintenance rehearsal – important for

Multi-Store Model of Memory 3. Long Term Memory Relatively permanent memory system that holds vast amounts of information for a long time. Two types of LTM: Procedural and Declarative Procedural: memory of actions and skills that have been learned previously. The ‘how to’ or ‘knowing how’ part of memory Declarative: memory of specific facts or events that can be explicitly stated or ‘declared’. The ‘knowing that’ part of memory. Personal experiences and facts Two types: semantic and episodic Episodic: memory of specific events or personal experience. AKA autobiographical memory Semantic: Memory of information we have about the world Facts that we know, but generally can’t recall exactly when we learnt them

Multi-Store Model of Memory Implicit and Explicit Memories Information retrieved from LTM is expressed either ‘Implicitly’ or ‘Explicitly. ’ Implicit and Explicit memories are not types of memory. They are the observable behaviour that occurs when the information is retrieved. Declarative memories are known as ‘explicit memories’ and Procedural memories are known as ‘implicit memories. ’ Explicit memories: the conscious retrieval and statement of memories, which includes recognition and recall. Implicit memories: unconscious retrieval of memory that does not require intentional, deliberate recall. Implicit memories include procedural memories, motor learning and classical conditioning.

Multiple Choice Questions

Part 4 - Process of Memory Dot point 2 - Interactions between specific regions of the brain (cerebral cortex, hippocampus, amygdala and cerebellum) in the storage of longterm memories, including implicit and explicit memories.

Brain Regions There are four main regions of the brain involved in the encoding, storage and retrieval of longterm memories. They are the cerebral cortex, hippocampus, amygdala and cerebellum.

Cerebral Cortex The cerebral cortex is the convoluted, thin outer layer of the brain. It is comprised of two hemispheres and each hemisphere contains four lobes. Long-term memories are spread out across the four lobes of the cerebral cortex. Generally, the area of the cerebral cortex where encoding (processing) took place, is where the information is stored. Cortical Lobe Type of Memory Frontal Lobe Procedural memories Episodic memories Memory for Language (Broca’s Area) Memory for Motor skills (Motor Cortex) Parietal Lobe Spatial memory (location in space and time) Occipital Lobe Visual memories Temporal Lobe Auditory memories (sound) Memory for names of colours

Hippocampus The hippocampus is a curved, tube-like structure, approximately 3. 5 cm long, located in the medial temporal lobe (middle area of the temporal lobe). There is a hippocampus in each of the hemispheres of the cerebral cortex. It is part of the limbic system and is associated with emotion and other functions. The hippocampus is responsible for the formation of declarative (episodic and semantic) memories. It turns short term memories into long term memories. The hippocampus does not store these memories within its structure, but assists in storing them in other areas of the brain. The hippocampus is responsible for the formation and storage of ‘explicit’ memories. The hippocampus also has an important role in spatial memory. Spatial memory: the memory for the physical location of objects in space. Implicit memories (procedural memories) are consolidated within the cerebellum, rather than the hippocampus. The hippocampus also plays a role in consolidating emotional memories, as it is connected to the amygdala.

Amygdala The amygdala is about 1. 5 cm long and is connected to the hippocampus in the medial temporal lobe. There is an amygdala in each hemisphere of the brain. The role of the amygdala is to process and regulate emotional reactions, particularly fear and anger. It allows us to process these emotions in other animals to perceive danger and alter our behaviour. For example: the amygdala processes the expression of a snarling dog as fearful and we move away from the dog (behaviour). Heightened emotions create stronger more vivid memories through the release of noradrenaline at the time of encoding. The amygdala is responsible for this and these emotional memories are often referred to as ‘flashbulb’ memories. The amygdala processes emotional memories which are implicit (involuntary), however, like the hippocampus, it does not store the memories within its structure. It assists in processing and storage of

Cerebellum The cerebellum has many functions: coordinating fine motor movement, regulating posture and balance, smooth movement and procedural (implicit) memories. Procedural memories of motor skills are encoded and temporarily stored by the cerebellum. Voluntary motor skills once learned are stored within the cerebral cortex. Involuntary motor skills (reflexes) remain stored in the cerebellum. This is where classically conditioned reflexes are stored. For example: Pavlov’s dogs salivating to the sound of a bell.

Answer Carousel

Describe the interaction between the amygdala and hippocampus in longterm memory formation and storage (3 marks). Outline the role of the cerebral cortex in memory formation and storage (2 marks)

Part 5 - Reliability of Memory Dot point 1 - methods to retrieve information from memory or demonstrate the existence of information in memory, including recall, recognition, relearning and reconstruction.

Measures of Retention The method of retrieval used by a person will determine how much information can be recovered from memory. Measures of retention assess how much information has been stored and can be retrieved from long term memory. Each measure of retention has a different sensitivity. Sensitivity refers to how well it retrieves information from memory. The three measure of retention are: recall, recognition and relearning.

Recall: the least sensitive measure of retention and involves reproducing information using few to no cues. There are three types of recall: free recall (no cues), cued recall (some cues) and serial recall (ordered recall, no cues). For example: short answer questions on a test use recall as the measure of retention.

Recognition: is a more sensitive measure of retention than recall. It involves identifying (recognising) the original learnt information. It may also involve selecting the correct alternative from a list of possible alternatives. For example: multiple choice questions on a test use recognition as the measure of retention.

Relearning: is the most sensitive measure of retention. It involves learning information that has been previously learned (and was therefore stored in LTM). Relearning has occurred when the learning takes less time and effort than the original learning. For example: revising content using cue cards. With each relearning of the terminology it is quicker to retrieve the definition when given the key term. Relearning is also known as the “Method of Savings” - used to measure the amount of information ‘saved’ from previous learning. A formula can be applied to assess how much time or effort has been ‘saved. ’

Reconstruction When memories are retrieved they are reconstructed in our STM. When information is stored in memory it is not an objective, completely accurate account (snapshot) of the event. Elements of the event that are deemed important by the individual are attended to and this is the information that is stored in LTM. When the information is retrieved it must be ‘put back together’ (reconstructed). During this process errors can occur, as not all information may be retrieved, causing us to ‘fill in the gaps’ with plausible information. The reconstruction process can leave a person open to alterations to the memory. Reconstruction: involves combining stored information with other available information to form what is believed to be a more coherent, complete or accurate memory. Reconstruction is an active process that is influenced by personal experience, prior knowledge, motivation, expectations, assumptions, environmental cues and our psychological state. Reconstruction occurs most commonly with episodic memories, but also occurs with semantic memories.

Part 5 - Reliability of Memory Dot point 2 - the effects of brain trauma on areas of the brain associated with memory and neurodegenerative diseases, including brain surgery, anterograde amnesia and Alzheimer’s disease

Brain Trauma Forgetting can occur due to a range of reasons. When forgetting is permanent, it is usually the result of an organic (biological/physical) cause. Brain trauma: any injury that impairs the normal functioning of the brain. The effect can be mild or severe, or temporary or permanent. Brain trauma can be incurred in a number of different ways. Two such causes of brain trauma are neurodegenerative diseases and brain surgery. Neurodegenerative disease: a disorder characterised by the progressive decline in the structure, activity and function of brain tissue. Neuro = neuron Degenerative = deteriorate/die Neurodegenerative diseases cause the neurons in the brain to deteriorate which impacts on our cognitive abilities.

Amnesia When the neurons deteriorate in structures that relate to memory, long term memories can be forgotten, or new memories cannot be formed. When this forgetting occurs, it is known as amnesia. Amnesia: the loss of memory that is inconsistent with ordinary forgetting. Memory loss may be partial or complete, or temporary or permanent. There are different types of amnesia, one of which is anterograde amnesia.

Anterograde Amnesia Anterograde amnesia: loss of memory only for information or events occurring after the trauma that causes amnesia. Anterograde amnesia is a forwards acting amnesia as new long term memories cannot be consolidated and stored. Any long term memories that were formed and stored prior to the brain trauma that caused the amnesia, will be retained and can be retrieved (remembered). Anterograde amnesia is the result of damage to the medial temporal lobe, specifically the hippocampus. A person with anterograde amnesia cannot form new declarative (explicit) memories, however, they are still able to learn and remember new procedural (implicit) memories For example: A person can develop a fear of spiders (implicit), even though they cannot remember why they are scared of spiders (explicit) A person can learn and remember a new skill (procedural/implicit), but not remember when they learnt it or describe how to perform the skill (declarative/explicit). *Retrograde amnesia is most commonly known. It is a reverse acting memory loss, as a person is unable to remember previously stored long term memories.

Brain Surgery Case studies from brain surgery have informed research into structures involved in memory. Surgery which damages or removes these brain structures impacts on memory formation and storage. Hippocampus Damage or removal of the hippocampus results in the ability to form semantic and episodic memories and store them in the cerebral cortex. Damage to the left hippocampus only will result in difficulties remembering verbal information. Damage to the right hippocampus only will result in difficulties learning and remembering the location of objects or places. Whilst it affects declarative memories, damage to the hippocampus does not impact on the encoding, storage and retrieval of procedural memories. Procedural memories can be learnt, however, the actual learning experience (episodic) will not be retained. Study of H. M. Molaison

Brain Surgery Amygdala Damage to the amygdala results in an inability to recall the emotional qualities of memories. It may also result in impaired ability to recognise facial expression of emotions, especially fear. Loss of the right amygdala more severely impacts on facial recognition. Problems with emotional memories are more likely to occur when there is damage to both amygdalae. Damage to the amygdala can also result in the inability to classically condition emotional responses. Fear responses will not be learnt if the amygdala is damaged. A person may have a scary encounter with a snake, however, they will only encode the explicit (declarative) information about the encounter. Therefore, the next time they see a snake, they can recall the previous encounter, but no the emotion that went with it.

Brain Surgery Cerebral Cortex Memory loss can occur when the cerebral cortex is damaged. The type of memory loss will be dependent on the lobe and are of the cerebral cortex that is damaged or removed. Each lobe stores specific declarative (explicit) memories. For example: damage to the pre-frontal cortex can result in the inability to remember events in sequential order. Damage in a particular hemisphere will also cause different memory problems. Left hemisphere damage results in worse recall for verbal material (names, phone numbers, etc). Right hemisphere damage results in worse recall for non-verbal material (facial recognition, spatial location, etc).

Brain Surgery Cerebellum Damage to the cerebellum results in the loss of memory for conditioned responses. For example: after classically conditioning dogs to salivate to the sound of a bell, if Pavlov had damaged the cerebellum of the dogs and then rang a bell, the dogs would no longer salivate. They would still salivate to the sight and smell of food, but the learning associated with the bell has been destroyed. Damage to either or both of the cerebellums can also result in impaired spatial learning and memory.

Alzheimer’s Disease A type of dementia characterised by the gradual widespread degeneration of brain neurons, progressively causing memory decline, deterioration of cognitive and social skills and personality changes. The most common type of dementia, accounting for 50%-75% of all dementia cases worldwide. It is estimated that over one million Australians suffer from Alzheimer’s disease. Symptoms: memory loss, forgetfulness, confusion, poor judgment, disorientation, impaired attention. As it progresses, mood and personality can change and loss of other functions (ability to talk, walk, control bladder, etc) can occur. One of the first symptoms is short term memory loss and as the disease progresses it impairs long term memories, specifically explicit (declarative) memories. Procedural memories are the last to be affected and only when the disease is very advanced. Earliest damage occurs in the hippocampus. This is slowly followed by a loss of neurons and synapses in the cerebral cortex, particularly in the temporal lobe, parietal lobe and frontal lobe.

Alzheimer’s Disease There is no single known cause of Alzheimer’s disease. There are unusual webs and tangles in brain cells leading to and from the hippocampus. This causes the neurons to die and the brain shrinks. Amyloid plaques form in the brain. ‘Beta amyloid’ is a protein that is produced by the body and normally is broken down in the brain. The plaques collect on the outside of neurons and attach to them. The amyloid reacts with the copper and iron which are naturally occurring in the brain and ‘rust’ the neurons. This destroys the synapses and neural messages can no longer be sent. In Alzheimer’s disease the brain also has neurofibrillary tangles, an abnormal build-up of proteins within neurons. The protein ‘tau’ accumulates within the neuron and inhibits the transfer of essential substances throughout the neuron. This causes the neuron to die. The plaques and tangles disrupt the normal organisation and communication between brain cells, causing them to die. Alzheimer’s brains also have lower levels of the neurotransmitter acetylcholine, which plays a role in the formation of memory. Currently there is no simple diagnostic test for Alzheimer’s disease and a definitive diagnosis can only be made after death, when an autopsy is performed.

Part 5 - Reliability of Memory Dot point 3 - the factors influencing a person’s ability and inability to remember information, including context and state dependent cues, maintenance and elaborative rehearsal and serial position effect

Factors influencing ability and inability to Generally, when we refer to our inability to remember we call it ‘forgetting. ’ Forgetting: the inability to access or recover information previously stored in memory. There are many theories on why we forget and often they include the lack of an appropriate cue to aid retrieval. Psychologists have also identified conditions that assist in the retrieval of memories. These include context and state dependent cues, maintenance and elaborative rehearsal, and serial position effect.

Context- and statedependent cues Retrieval cues assist in recovering information previously stored in long term memory. There are two types of cues: context dependent and state dependent. Context dependent cues: environmental cues in the specific situation (context) where a memory was formed that act as retrieval cues to help access the memories formed in that context. For example: learning the Unit 3 & 4 Psychology content at school and then sitting the exam at school. The context of ‘school’ will act as a cue to assist in retrieving the previously learnt information. After witnessing a crime, an eyewitness may remember more details by returning to the scene of the crime as the context of the ‘crime scene’ acts as a cue to aid retrieval of those previously stored memories. State dependent cues: an individual’s internal physiological and/or psychological state at the time the memory was formed, acts as a retrieval cue to help access those memories. For example: Putting your keys down when intoxicated and not being able to find them when sober. Returning to the state you were in (intoxicated) when you put the keys down, will act as a cue to retrieve the information. Listening to a sad song or watching a sad movie puts you in a ‘sad’ state of mind, which may act as a cue and trigger memories formed when in that same emotional state.

Maintenance and Elaborative Rehearsal is the process of consciously manipulating information to keep it in STM, to transfer it to LTM or aid storage and retrieval. Two types of rehearsal: maintenance and elaborative Maintenance Rehearsal: rote learning, repetitive and keeps information in STM, does not assist encoding for storage in LTM. Information kept in STM through maintenance rehearsal restricts the amount of new information that can enter STM. Elaborative Rehearsal: linking new information in a meaningful way with other new information or information already stored in LTM. Elaborative rehearsal is a more active and effortful process than maintenance rehearsal – important for encoding.

Serial Position Effect Studies have found that when using free recall, information in a list is remembered in a certain order. Serial position effect: free recall is better for items at the beginning and end of a list, than items in the middle. Two effects: Primacy effect and Recency effect Primacy effect: superior recall of items at the beginning of a list. Recency effect: superior recall of items at the end of a list.

Serial Position Effect What causes the serial position effect? Primacy effect occurs as the items at the beginning of the list have time to be rehearsed and transferred into LTM. Recency effect occurs as the items at the end of the list are still in STM. Items in the middle of the list do not have time to be rehearsed and are displaced (pushed out) of STM to make room for the items at the end of the list. Therefore, the middle items are forgotten. Recency effect only occurs if the items are recalled immediately after learning. If there is delay the words at the end of the list will be displaced from STM in favour of new information that has our attention.

Part 5 - Reliability of Memory Dot point 4 - the reconstruction of memories as evidence for the fallibility of memory, with reference to Loftus’ research into the effect of leading questions on eye-witness testimonies.

Fallibility of Memory Construction Alterations can occur when memories are reconstructed, which can lead to false or inaccurate memories. These errors (fallibility) of memory make it difficult to use eye-witness testimony as a reliable source of information. Eyewitness testimony: any firsthand account given by an individual of an event they have seen. Eyewitness testimony, as studied by Loftus, is not always accurate as the memories are reconstructed and can be influenced by leading questions. Leading question: a question which has content or is phrased in such a way as to suggest what answer is desired or lead to the desired answer. Leading questions use language that causes a person to make assumptions that may insert false information into their retrieved memory. For example: research conducted by Loftus has found that when asked leading questions such as “Did you see children get off a school bus? ” participants were more likely to report seeing a school bus a week later compared to those who were not asked the leading question. Emotive language can also cause false information to be inserted into retrieved memories For example: there is also evidence to suggest that emotive language such as ‘car smash’ as opposed to ‘car crash’ will result in an increase of reported damage at the scene of a crime.

Loftus’ Research Two experiments conducted by Loftus (1974), highlight how leading questions can influence the reconstruction of memories. Experiment 1: 45 volunteer university students. Students were shown seven short videos of car accidents After each video, participants wrote a description of the accident They were also asked questions about the accident, including a ‘leading’ question that required them to estimate the speed of the car Five conditions were used in the experiment with nine students randomly assigned to each condition. Each condition used a different verb in the leading question (smashed, bumped, collided, hit and contacted)- For example: “About how fast were the cars going when they smashed into each other? ” The wording of the question influenced the speed estimated More intense or emotive words, such as smashed and collided, had the highest speed estimates

Experiment 2: Loftus’ Research 150 volunteer university students Randomly assigned to one of three conditions and viewed a one-minute video that included a four-second scene of a multiple car crash Each group was then asked questions, including a ‘leading’ question Group 1 was asked: “About how fast were the cars going when they smashed into each other? ” Group 2 was asked: “About how fast were the cars going when they hit each other? ” Group 3 was not asked about the speed of the cars ‘Smashed’ had a higher speed estimate than ‘hit’ One week later they were asked another set of questions, including a critical question: “Did you see any broken glass? ” The more emotive word ‘smashed’ caused participants to recollect glass that did not exist in the video 16 of the 50 participants in group 1 responded with ‘Yes’ compared with 7 participants in group 2 and 6 participants in group 3 Loftus concluded that over time, the two sources of information (the video and questions) led to a reconstruction of the memory that integrated both and distorted the memory. This creates an issue with eyewitness testimony, as every time a memory is retrieved it is reconstructed and subject to alterations through the use of leading questions and other information.

Exam Practise Let’s do the chapter 7 test together using the techniques we have practised so far.