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LEARNING INHERITED BEHAVIOURS AND CLASSICAL CONDITIONING Defining Learning Humans are born very poorly equipped for independent survival and must spend most of the first 10 to 15 years of their lives learning to survive. The word learning refers to the relatively permanent changes in behaviour and cognition as a result of experience. It is ongoing, adaptive, can be intentional or unintentional, active or passive. Learning is relatively permanent… Learning is defined as being relatively permanent because it cannot be something that is present one moment and gone the next, or ‘here today and gone tomorrow.’ Learning can be intentional or unintentional… Learning can occur intentionally; such as when someone makes the choice to learn how to play the piano and takes lessons. Learning can be unintentional; such as while watching or hearing someone else playing the piano. Learning can be active or passive… Learning can be active, such as reciting your times tables in order to remember them. Learning can be passive, such as when hearing about an important event on the news or reading something in the newspaper. Learning is a change in behaviour… The notion of change is an important part of the definition of learning, because something must be different about the organism after learning has taken place. This change may be immediate, or it may be delayed and occur over a period of time after the learning. BEHAVIOUR NOT DEPENDENT ON LEARNING Learning account for most of the behaviours that are observed in humans and animals, however not all behaviour has to be learned. What are some behaviours you can think of that are not learned? BEHAVIOUR NOT DEPENDENT ON LEARNING Reflexes Fixed-action patterns REFLEX ACTIONS Automatic, involuntary behaviours that do not require prior experience and occur in the same way each time are known as reflexes. Blinking when wind blows in your face Moving your hand from a hot object Reflexes allow people to deal with specific stimuli that are important for their protection or survival through rigid, automatic responses. FIXED-ACTION PATTERNS A fixed-action pattern of behaviour occurs when all members of a species produce an identical response to the same specific environmental stimuli. The mechanisms that control the behaviours are ‘fixed’, in that they are genetically programmed into the animal’s nervous system and appear to be unable to be changed as a result of learning. A fixed-action pattern of behaviour is a behaviour inherited by every individual member of a species, or if the behaviour is sex-specific, by all members of one sex in the species. Fixed-action patterns differ from reflexes in that a reflex, although inborn, usually consists of a single or simple response, whereas a fixed-action pattern is more complex, usually consisting of a sequence of responses. Eg. Salmon migrate thousands of kilometres through ocean waters to spawn in the rivers in which there were born. BEHAVIOUR DEPENDENT ON MATURATION Maturation is a developmental process leading towards maturity, based on the orderly sequence of changes that occur in the nervous system and other bodily structures controlled by genetic inheritance. Crawling at 8-10 months of age. During puberty, the change in a boy’s voicebecoming deeper. DIFFERENT KINDS OF LEARNING There are many different ways to learn that are not necessarily different from one another. An individual can shift from one type of learning to another in many real-life situations. The form of learning that we will be looking at is called conditioning. Conditioning is a form of learning that emphasises the relationship between stimuli and responses. Stimuli are events that trigger responses. Conditioning is to do with how learning occurs. CLASSICAL CONDITIONING Ivan Pavlov Russian psychologist Ivan Pavlov was the first to describe classical conditioning as a learning process when he was investigating the digestive system of dogs. He was particularly interested in the role of salivary secretions in the digestion of food. Today he is better remembered for his work on classical conditioning. Pavlov surgically moved the salivary gland of a dog into its cheek, and put a tube into the gland which was attached to a test tube. The dog was placed into a harness to prevent any sudden attempts to escape during the test period. Pavlov knew that dogs would salivate if food was placed in their mouths, but he noticed that they would also salivate before they were given food. At the time he believed that digestion involved a series of reflexes, so he set out to discover what stimulus caused this response of salivation even before the dogs received food. Various stimuli were presented to the dog, and the effects on its rates of salivation were measured. Pavlov noticed that the dogs began to salivate to other stimulus’ other than the food. For example when the lab technician entered the room to give the dogs the food they began to salivate. Salivation was caused by the lab technician and not the food. Pavlov began to test this using other stimulus’ such as a bell, a musical tone, clapping, a light… The dogs had learnt to associate different stimuli with food which caused them to salivate, rather than the food being the cause. Key elements of classical conditioning Classical conditioning refers to a form of learning that occurs through the repeated association of two (or more) different stimuli. A stimulus is any event that elicits (produces) a response from an organism. A response is a reaction by an organism to a stimulus. There are four key elements of classical conditioning. The unconditioned stimulus, unconditioned response, conditioned stimulus and conditioned response. The unconditioned stimulus (UCS) is any stimulus that consistently produces a particular, naturally occurring, automatic response. (Food). The unconditioned response (UCR) is the response that occurs automatically when the UCS is presented. It is reflexive, involuntary response that is predictably caused by a UCS. (Salivation). The conditioned stimulus (CS) is the stimulus that is neutral at the start of the conditioning process and does not normally produce the unconditioned response. (Lab technician). Through repeated association with the UCS, the CS triggers a very similar response to that caused by the UCS. Association refers to the pairing or linking of one stimulus with another stimulus. Lab technician and food. The conditioned response (CR) is the learned response that is produced by the CS. (Salivation). Classical conditioning example: Flora has a cat name Tiger. Tiger loves eating FishDelish, a brand of cat food, which Flora feeds to Tiger every night. Flora is curious about Tiger’s behaviour, and she wants to understand how Tiger has come to behave and respond in a particular way. Flora’s routine when she comes home from work is as follows: she puts her keys on the kitchen sink (which makes a clanging noise each time), then she prepares Tiger’s dinner. After several days of this routine, Flora noticed that Tiger would run up to her and salivate whenever she put her keys on the sink. BEFORE CONDITIONING DURING CONDITIONING AFTER CONDITIONING Neutral stimulus (NS): Neutral stimulus (NS): Conditioned stimulus (CS): Unconditioned stimulus (UCS): Conditioned response Conditioned response (CR): (CR): Unconditioned response (UCR): Learning Activity 3: Identifying elements of classical conditioning. KEY PROCESSES IN CLASSICAL CONDITIONING The key processes in classical conditioning are: - Acquisition Extinction Stimulus generalisation Stimulus discrimination Spontaneous recovery ACQUISITION In classical conditioning, each paired presentation of the CS with the UCS is referred to as a trial. Acquisition is the overall process during which the organism learns to associate two events (the CS and the UCS). During acquisition, the presentations of the CS and the UCS occur close together and always in the same sequence. The duration of the acquisition phase is determined by how many trials is takes for the CR to be learned. The shorter the period of time between the presentation of the CS and the UCS the faster the acquisition. The end of the acquisition phase is said to occur when the CS alone produces the CR. At this point, conditioning is said to have taken place. EXTINCTION A conditioned stimulus-response association is not necessarily permanent. The strength of the association may fade over time or disappear altogether. Extinction is the gradual decrease in the strength or rate of a CR that occurs when the UCS is no longer presented. Some behaviours are extinguished quickly, others take longer to extinguish. SPONTANEOUS RECOVERY Extinction of a conditioned response is not always permanent. 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. Spontaneous recovery does not always occur, and when it does it is short lived. The CR tends to be weaker than it was originally (during acquisition). If the extinction procedure is repeated several times, eventually the CR will disappear altogether and spontaneous recovery will not occur at all. STIMULUS GENERALISATION Once an organism has learned to respond to a conditioned stimulus, other stimuli that are similar to the CS may also trigger the CR, but usually at a reduced level. Stimulus generalisation is the tendency for another stimulus- one that is similar to the original CS- to produce a response that is similar (but not necessarily identical) to the CR. The greater the similarity between stimuli, the greater the possibility that a generalisation will occur. Stimulus generalisation has a valuable adaptive role, but can also be detrimental in some situations. STIMULUS DISCRIMINATION In classical conditioning, 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. Eg. If someone is afraid of a particular dog, but is not bothered by any other breed of dog in a similar situation. CLASSICAL CONDITIONING OF BEHAVIOUR Classical conditioning is one of the simplest forms of learning. Classically conditioned behaviours are like reflexes in that they occur involuntarily, however they are unlike reflexes in that they are learned. A conditioned reflex is an automatic response that occurs as a result of previous experience. A conditioned reflex requires little conscious thought or awareness on the part of the learner. By learning to associate stimuli in our everyday experience, we gain information about our environment, some of which we take for granted but which is nevertheless valuable. Eg. Packing up your books at the sound of the bell for the end of the lesson Answering the door bell or phone when it rings Listening for thunder after a flash of lightening Conditioned reflexes include a range of behaviours, one of the most researched is the emotional response. Sometimes an emotional response such as fear or anger to a specific stimulus is learned through classical conditioning. A conditioned emotional response is an emotional reaction that usually occurs when the autonomic nervous system produces a response to a stimulus that did not previously trigger that response. Eg. Cringing at a dentist drill. While it might be beneficial to form a fear of something that could harm you, it may be psychologically harmful to form a fear about something that does not normally harm you. Read Little Albert. CLASSICAL CONDITIONING IN PRACTICE Classical conditioning is used in many therapeutic settings, which aim to rid people of undesirable behaviours. Aversion therapy Systematic desensitisation Treatment of persistent bedwetting AVERSION THERAPY When people develop unwanted behaviours (that are harmful) such as substance abuse, gambling addiction, inappropriate sexual behaviours, it is often difficult to help them permanently stop the unwanted behaviour. It is especially hard when the behaviour is followed by a sense of pleasure or relief. Aversion therapy is a form of behaviour therapy that applies classical conditioning principles to inhibit (block) or discourage undesirable behaviour by associating it with an aversive (unpleasant) stimulus. This may be a feeling of disgust, pain or nausea. The aim is to suppress or weaken the undesirable behaviour. Eg. To stop nail biting- painting nails with a foul tasting substance. The association between the unpleasant stimulus and the unwanted behaviour is learned very quickly. Aversion therapy was first used in the 1930’s to treat alcoholism, by giving alcoholics an electric shock whenever they could see, taste or smell alcohol. Today instead of using electric shocks, alcoholics are given nausea inducing drugs paired with alcohol consumption to make the patient feel ill. UCS- NAUSEA DRUGS UCR- FEELING ILL CS- ALCOHOL CR- FEELING ILL The limitation to this is that some alcoholics will avoid alcohol while taking the drugs but return to it once therapy is finished. This means that the learned aversion often fails to generalise to situations other than those under which the learning takes place. Therefore at times the results of aversion therapy are often short lived. SYSTEMATIC DESENSITISATION In most cases, a classically conditioned response will become extinguished if the UCS is not paired with the CS at least occasionally. Systematic desensitisation is a kind of behaviour therapy that attempts to replace an anxiety or fear response with a relaxation response through a classical conditioning procedure. This means the client must associate being relaxed with the anxiety or fear stimulus by a series of graded steps. Joseph Wolpe developed this theory and his steps are as follows: 1. 2. Teach the person to relax. Break down the fear arousing stimulus into a series of graded steps. Steps are graded from most fear arousing to least fear arousing. 3. Eg. Consider a person with a fear of flying. Most frightening Experiencing mid-air turbulence Taking off Taxiing down the runway Boarding the plane Waiting to get on the plane Travelling to the airport in a car Buying a plane ticket Least frightening The therapist would then ask the patient to imagine the least frightening scene on the list. When they can imagine doing this they would be ask to imagine the next step and so on. In the end the patient should be able to imagine the most fearful stimulus without becoming afraid. Real life desensitisation is the most successful. This eventually leads to the fear of flying being eventually overcome. TREATMENT OF PERSISTENT BEDWETTING Some children persist in wetting their beds long after they are toilet trained an out of nappies. This is called enuresis. Although some cases are caused by physiological problems the condition is frequently found to be associated with problems during: -toilet training -stressful situations -underlying emotional responses. It is believed that enuresis was caused by an individual failing to wake up in response to the stimuli arising from a full bladder and that classical conditioning could fix this. If a person could awaken when the bladder was full the problem would be fixed. A buzzer was used to awaken the sleeping person following the stimulation from a full bladder. After a series of these presentations, in theory, a person should awake only to the feeling of a full bladder and not the buzzer. A gauze pad was positioned appropriately so that the first drop of urine was detected and set of a circuit which sounded the buzzer. This proved to be a successful method for curing bed wetting. ETHICAL ISSUES IN CONDITIONING BEHAVIOUR Confidentiality- a participants right to privacy, meaning that in a study details about the participants identity cannot be revealed unless their written consent is obtained. In Little Alberts case, his details were published along with his photos in a research article without the written permission from his mother. Voluntary participation- the researcher must try to ensure that participants’ involvement in the research is voluntary. Participants must not be put under any pressure to take part in the study. Although Little Alberts mother did volunteer her son to participate in the experiment on conditioning, it is questionable whether she was informed as to what was actually going to happen to her son in the experiment. Informed consent- wherever possible participants must be appropriately informed of the nature and purpose of the investigation. This must be appropriately documented. It is unlikely that Little Alberts mum was properly informed about what was going to occur throughout the experiment and the conditions that she was agreeing to. There is no documented paperwork to indicate otherwise. Withdrawal rights- The researcher must inform participants of the nature of the research and that they are free to participate or to decline to participate or to withdraw from the research. Little Alberts mother was not with her child when he was being conditioned and Little Albert was too young to make the decision himself. Meaning that even if he should have been withdrawn he could not have. Related to the lack of informed consent. Deception- when it is necessary for scientific reasons to conduct a study without fully informing participants of its true purpose prior to commencement, the researcher must ensure that participants do not suffer distress from the research procedure. If Little Alberts mother was not informed about the exact procedure for the conditioning experiment there is an element of deception involved. This is unethical as the experiment did cause distress for Little Albert and his mother was presumably not informed about this. Debriefing- The researcher must provide an opportunity for participants to obtain appropriate information about the nature, results and conclusion of the experiment. According to the experimenters Little Alberts mother moved away before the experimenters had a chance to debrief her and reverse Alberts conditioned behaviour. Other reports suggest that although the experimenters knew well in advance the mother was leaving, they did not attempt to follow the debriefing guidelines. ONE-TRIAL LEARNING AND TASTE AVERSION Take a minute to think of a food you don’t like… Why don’t you like it? These reasons are personal and subjective. Sometimes our dislike of food occurs suddenly, yet with little consideration. This is called taste aversion. TASTE AVERSION A taste aversion is a conditioned response that results from a person or animal establishing an association between a particular food and being or feeling ill after having consumed it at some time in the past. There is an association between the CS (taste/smell) and the UCS (nausea), the difference is that it is usually acquired with just one trial. ONE-TRIAL LEARNING One-trial learning is a form of learning involving a change in behaviour that occurs with only one experience. While one-trial learning has some of the characteristics of classical conditioning, there are various aspects which do not follow this model. One-trial learning Classically conditioned responses usually take a number of associations or pairings to occur, and they can extinguish relatively quickly. One-trial learning is quickly acquired and considerably resistant to extinction. In classical conditioning the CR occurs immediately after the CS is presented, whereas in one-trial learning the CR can occur as much as a day or so after the food. One-trial learning In one-trial learning generalisation does not normally occur. Read John Garcia experiment page 457.