Introduction to Learning and Basic Concepts PDF

Introduction to Learning and Basic concepts Dr. Kübra CELIK Syllabus Week 1 Introduction to Learning Midterm (%40) Week 2 Habituation, sensitization Week 9 Theories of Learning Week 3 Behavioralism & Classical Week 10 Social Learning conditioning...

Introduction to Learning and Basic concepts Dr. Kübra CELIK Syllabus Week 1 Introduction to Learning Midterm (%40) Week 2 Habituation, sensitization Week 9 Theories of Learning Week 3 Behavioralism & Classical Week 10 Social Learning conditioning Week 11 Neurobiology of Learning and Week 4 Mechanisms of classical Memory (LTP & LTD) conditioning Week 12 Memory Week 5 Operant conditioning Week 13 Memory Week 6 Reward pathways and motivational mechsnisms Week 14 An overview of the semester Week 7 Controlling behavior: Final exam (%60) avoidance, punishment, extinction Sources Learning theories : An educational perspective, Dale Schunk, Sixth Edition, Pearson The principles of learning and behavior, M.Domjan 7th edition Ppt presentations What is learning? Learning is the permanent change in behavior that results from experience. Learning is long-term changes that occur in the neural mechanisms of behavior. What is learning? It begins in embryonic period until death. All organisms learn Learning is the adaptation process that ensures survival. Environment changes the learning process and learning changes the environment. Adaptation at the individual level occurs through learning. Lasts for the lifetime of the individual Criteria for learning Acquire a new behavior Change in behavior frequency Change in pace of behavior Changing the intensity of the behavior Different responses to the same stimulus when the level of complexity in behavior changes Criteria for learning It is not only stimulus Unconcsciously processed information Characteristics of the organism involves in learning Must be observed by others More than a single stimulus and it takes more than a single moment (i.e.should be generalizable and sustainable). Learning and Performance Learning can only be measured by an observed change in behavior BUT sometimes learning can be behaviorally silent. All of the observable things that an individual does, are collectively called performance. Performance can be affected by many things, such as motivation and environmental stimuli. Learning is just one of the factors that affecting performance. Basic Concepts Stimulation: The condition in the organism that causes a response. physical, organic, psychological Response: The behavior of the organism (consciously or unconsciously) in against stimuli. Performance: Capacity required for a particular job What is behavior? The organism's response to the environment Simple reflexes → blink Complex behaviors → nutrition Complex emotional responses → addiction Stimulus Causes a reaction in the organism, causing changes in the behavior of the organism, Sensory inputs Intensity, duration effect More severe stimuli are more likely to cause a reaction in the organism. As the duration of the stimulus increases, the probability of causing a reaction increases. Response Tiggered by stimulus It appears automatically or Caused by environmental factors It consists of much more complex behaviors Inherited Behavior Patterns Many learned behaviors are actually extensions of our innate behavior patterns. Reflexes Kinesis and taxis (behavior used by primitive animals to adapt to environmental conditions) Modal behavioral patterns Reflex Stimulus→ response Unconditional behavior Some rhythmic reflexes (itching, swallowing, chewing, walking) are involuntary and open to voluntary control and adjustment. Central pattern generators lead unconscious behaviors such as reflex Kinesis and Taxis An automatic response to the stimulus with whole body Kinesis (indirect), taxis (direct) Decreased humidity (stimulus) → reaction Light (stimulus) → orientation to darkness (response) Modal Action Structure A temporal and spatial structure of behavior common to members of a species Reaction Chain Tactile arousal → Searching reaction → Oral stimulation → Sucking → Milk → Sucking more → Full stomach → Stop sucking Difference between reflex and modal action Modal behavior pattern → Continues to the end regardless of the outcome Reflex → every response has a stimulus. And for the next reaction to occur, that stimulus must be present in the environment. Learning vs Instincts Modal action patterns are instinctive Instinctive behaviors were assumed to be determined primarily by the genetic and evolutionary history of a species, Learned behaviors were assumed to be acquired during the lifetime of the organism through its interactions with its environment. Instincts are inborn complex patterns of behaviour that exist in most members of the species, and should be distinguished from reflexes, Genetics and epigenetics → behavior Genetics of behavior  Genes do not directly control behavior, but the RNA and proteins encoded by genes affect the brain at different times and at many levels. Jim Twins These twins were adopted at the age of four weeks. Larry. Both of the – Both named their pet dog "Toy." adopting couples, unknown to each other, named their son Jim. – Both had some law-enforcement training and had been a part-time Upon reunion of the twins when they were 39 years old, Jim and deputy sheriff in Ohio. Jim have learned that: – Each did poorly in spelling and well in math. – Both twins are married to women named Betty and – Each vacation in Florida in the same three-block- divorced from long beach area. women named Linda. – Both twins began suffering from tension headaches at eighteen, – One has named his first son James Alan while the other named his first gained ten pounds at the same time, and are six feet tall and 180 son James Allan. pounds. – Both twins have an adopted brother whose name is  Drosophila larvae activity level and locomotion differs. Larvae called 'rover' travel much longer distances Others, called 'sitters', are relatively quiet. These traits are inherited and rover mothers or fathers have rover offspring, and sitter parents have sitting offspring. Marie sokolowski FOR Gene Epigenetics effects learning and memory Contextual fear conditioning taking an animal and placing it in a novel environment, providing an aversive stimulus, and then removing it. Thanks ☺ Habituation and Sensizitation Dr. Kübra CELIK  Although we think of our memory as positive recollections of our previous experiences or thoughts, in reality the vast majority of what we have in our memory are negative memories. The brain has the ability to ignore unnecessary information. This type of information is provided by creating inhibition in related pathways, and this effect is called habituation. This type of memory is called negative memory.  Conversely, if the incoming information is of a nature to have significant consequences, such as pain or pleasure, the brain uses a different mechanism to amplify such information and store it as memory traces. This type of memory is called positive memory. Occurs by facilitation of synaptic pathways →The result is memory sensitization. Special areas in the basal limbic areas of the brain subconsciously decide what information is important And according to this decision, information or thought is either stored as sensitized memory or suppressed. Sensitization Inverse of habituation The repeated stimulus, if paired with a pleasurable or irritating stimulus, produces an increasingly larger response (e.g., the mother may wake up immediately to the sound of her baby, even though she is not aroused by many noises). If the facilitator terminal is stimulated together with the sensory terminal, serotonin is released from the facilitator synapse to the sensory terminal (presynaptic). Calcium increase → serotonin increase → synapse is faciliated.  Long-term habituation and sensitization involve structural changes in the presynaptic terminations of sensory neurons. Long-term synaptic facilitation is specific to the synapse. Effects of repeated stimulation According to Descartes, each occurrence of the eliciting stimulus will produce the same reflex reaction. Contrary to Descartes, elicited behavior is not invariant Elicited behavior can either decrease or increase through the activation of habituation and sensitization mechanisms. Because these are some of the simplest and most basic forms of learning, Visual habituation  To induce fear, one group of students was told that they could get shocked at some point when they saw the pleasant pictures but not when they saw the unpleasant pictures. The second group of participants received a shock threat associated with the unpleasant pictures but not the pleasant pictures. Shock was never delivered to any of the participants, but to make the threat credible, they were fitted with shock electrodes. To measure fear-potentiated startle, the magnitude of the eyeblink response to a puff of air was measured during presentation of the pictures. Habituation and Sensitization of Emotions and Motivated Behavior Habitiation and sensitization are primary concerns of classical and operant conditioning. The concepts of habituation and sensitization also have been extended to changes in more complex emotions (Solomon & Corbit, 1974) and various forms of motivated behavior, including feeding, drinking, exploration, aggression, courtship, and sexual behavior DRUG ADDICTION? Why addicts keep taking drugs? For the pleasure or escaping from the misery? Conditional analgesia is a defense system of the body by habituation. The body produces opiates as a defense against a harmful stimulus or physical injury. → morphine When trauma associated with shock activates opiate production Conditional analgesia occurs. When conditional analgesia takes place, the shock begins to be less painful. Conditioned drug tolerance When a drug is given repeatedly, its effect gradually decreases. In this case, tolerance to that drug develops. For this reason, higher doses of medication are required to achieve the first effect. Tolerance develops with almost all psychoactive drugs. Thanks ☺  Behaviorism and Classical Conditioning Dr. Kübra CELIK Behaviorism Behaviorism is a theory of learning based on the idea that all behaviors are acquired through conditioning, and conditioning occurs through interaction with the environment. Behaviorists believe that our actions are shaped by environmental stimuli. 1913 J. Watson → Methodological behaviorism Methodological behaviorism states that observable behavior should be studied scientifically and that mental states and cognitive processes don't add to the understanding of behavior. Radical behaviorism → Skinner Radical behaviorism is rooted in the theory that behavior can be understood by looking at one's past and present environment and the reinforcements within it, thereby influencing behavior either positively or negatively Edward Thorndike (1874-1949) Believed psychology should study behavior, not elements/conscious experiences Developed a theory of learning Connectionism Association between stimuli and responses Connection more likely to form if followed by a reinforcement Response-units: simplest elements of behavior  Law Effect behavior that produces a good outcome becomes associated with a certain situation; when the situation recurs, the behavior is likely to occur again (“stamping in”) likewise, a behavior with a bad outcome is less likely to occur again (“stamping out”) → foundations of operant condtioning https://youtu.be/LsdrhlxTcVY Ivan Pavlov (1849-1936) Read about Darwin, studied animal physiology 1904 Nobel Prize on digestion Foundations of classical conditioning Classical conditioning is a technique frequently used in behavioral training in which a neutral stimulus is paired with a naturally occurring stimulus. Eventually, the neutral stimulus comes to evoke the same response as the naturally occurring stimulus, even without the naturally occurring stimulus presenting itself. Conditioned reflexes Before conditioning US: unconditioned stimulus UR: unconditioned response NS: neutral stimulus Conditioned reflexes After conditioning CS: conditioned stimulus CR: conditioned response  Eye blink conditioning Tone (US) → Blink (UR) Tone sound (CS) → Blink (CR) More than 300 trials are required for conditioning to occur in this setup. Eye blink conditioning Conditioned suppression Known as conditioned fear Sound → CS Shock → US CS takes couple of minutes, US takes couple of seconds. https://www.youtube.com/watch?v=ZlZekx1P1g4 Important !! Classical conditioning is not just about reflexes, It can also be applied to purposive behaviors. Goal Tracking- Sign Tracking conditioning CS → metal bar US → food CR → pecking the metal bar  The number of trials is a gradualincreases as (5,10,15,20,25) A total of 25 attempts are made per day. The metal bar appears after the food is fed into the container. The food is given regardless of what the subject is doing. The bar is placed to the left of the foodbox and presented for 5 seconds. As soon as the food is placed on the tray, the bar goes back. The duration of the food in the foodbox is 4 seconds https://www.youtube.com/watch?v=KnJPPaiJG6Y Taste Aversion CS → food with a distinctive taste and odor US → a chemical causing stomachache After a while Food → Aversion (CR) Avoidance therapy in drug addiction  The power of the taste and smell ! A single conditioning between CS and US is sufficient for realization. Pavlovian conditioning requires repetition over and over. In taste-avoidance conditioning, the time between CS and US can be extended up to 24 hours. In Pavlovian conditioning, this interval is limited to seconds or minutes. Key Factors That Determine Conditioning The intensity of the stimulus Time interval between CS and US Measurement of response The criterion of the conditioning Time and Syntax Relationship Between CS-US Meat at first or the bell? Short-delay conditioning → the strongest conditioning First CS (the bell) During CS → give US (meat) Long-delayed conditioning The time between CS and US is long Delay causes conditioning weakness CR appeared with the ring tone in the first trials. As conditioning progressed, the emergence of CR approached the beginning of meat presentation.  Trace conditioning First, CS starts and ends. After a while US starts. Conditioning occurs between the trace of CS and US The time between CS and US → conditioning weakness Temporal conditioning No CS The US presentation is repeated at a fixed time interval. After a while, CR starts to come before US Time actually turns into CS Simultaneous conditioning CS and US are presented simultaneously. In this sequence, conditioning is either ambiguous or does not occur at all. Conditioning occurs as long as the CS indicates that the US will come. Reverse conditioning First, US Then CS No conditioning CS MUST BE BEFORE THAN US FOR CONDITIONING!!  For an observed change in behavior to qualify as a Pavlovian conditioning, it must be distinguished from habituation and sensitization effects. Habituation → Response decreases Pavlovian conditioning → Response increases Connectivity Between CS-US In order to establish a connection between two stimuli; Co-occurrence rate of stimuli The probability of distinguishing it from other stimuli in the environment is calculated. Conditioning by Model: After evaluating all stimuli, conditioning occurs if one of these stimuli (CS) indicates the future of the unconditioned stimulus as more reliable than other stimuli. A very rapid increase in the strength of the connection occurs in the first attempts, the amount of increase decreases as the trials progress and approaches a constant value towards the end. CS-US compliance A drink with a taste, light and sound given all together CS→ taste US → stomachache CS→ light and sound US → electric shock In other studies, it was found that the compliance of CS US may differ according to biological species. The organism can be conditioned depending on which sense organ it uses more dominantly and what kind of clues it uses while trying to find food. Severity of CS and US The more intense the stimuli, the faster the conditioning develops. In the response suppression mechanism, a high-intensity shock (US) suppresses the response completely, while a lower-intensity shock reduces the response to a certain extent. In fact, the conditioning develops more depending on the salience of the CS rather than the severity. A sound may not be very loud, but it becomes more pronounced if the environment is very quiet. Secondary Conditioning UR US CR CS CS CR CR Secondary Conditioning A neutral stimulus can cause a conditioned response without being directly coupled to the unconditioned stimulus. Organisms can link unconditioned stimuli not only between directly related stimuli, but also between more distant and indirectly related stimuli. Example: The male rats approach the female not only for the appearence but the scent. Sensory Preconditioning Pair them a few times UR CR CS CS CR US Sensory Preconditioning In order to establish a connection between two stimuli through classical conditioning, there must be two stimuli in the environment. But the phenomenon of sensory preconditioning shows that this is not true.  Extinction If the conditioned stimulus is presented repeatedly without the unconditioned stimulus, the conditioned response disappears. A new inhibitory link is formed between the conditioned stimulus and the unconditioned stimulus. Recovery of response Spontaneous recovery → Recovery of habitual response The reappearance of the conditioned response following a period of extinction. Inhibition of behavior It means actively suppressing a reaction that would normally occur. During conditioning, an excitatory connection is established between the CS and the US. In extinction, an inhibitory connection occurs between these two stimuli. «The main function of the cortex is inhibitory connections.» Pavlov Conditioned inhibition In classical conditioning, the CS becomes a signal for the coming US. In inhibitory conditioning, the CS becomes the signal for the absence of the US. Generalization constancy in perception Response to all similar CS The more a stimulus is similar to a conditioned stimulus, the more likely it is to generalize. Discrimination The opposite of generalization. The organism begins to respond to a single stimulus among similar stimuli, distinguishing it from other stimuli. (Conditional stimulus only) selective perception? Blocking According to Kamin (1969), if the presence of preconditioned noise prevents the conditioning of the added light, then blocking has occurred. When a new neutral stimulus is matched with the same natural stimulus after the classical conditioning process occurs, the blocking of the new neutral stimulus by the conditioned stimulus in the previous conditioning is called the blocking or blocking effect. It means new CS CAN’T MATCH WITH THE US. Time is not enough for the match Eg. The bell stimulates salivation, if I give new CS, it won’t be enough for the new learning. Rescorla Wagner Model - Excessive Expectation Effect Arousal Conditioning → Actual US > Expected US According to the Rescorla Wagner model, an unexpectedly large US increases the conditioning Inhibitory Conditioning→ Expected US > Actual US On the other hand, if an unexpectedly small US is received, it inhibits the conditioning.  Rescorla Wagner Model A model that calculates exactly how much the organism learned in each trial. A very rapid increase in the strength of the connection occurs in the first attempts, the amount of increase decreases as the trials progress and approaches a constant value towards the end. Connectivity between CS-US (Rescorla Wagner) In order to establish a connection between two stimuli;Co-occurrence rate of stimuliThe probability of distinguishing it from other stimuli in the environment is calculated. Conditioning by Model After evaluating all stimuli, conditioning occurs if one of these stimuli (CS) indicates the future of the unconditioned stimulus as more reliable than other stimuli. Learning by Model A very rapid increase in the strength of the connection occurs in the first attempts, the amount of increase decreases as the trials progress and approaches a constant value towards the end. Extinction according to Rescorla Wagner Theory It defines extinction as UNLEARNING IS IT REALLY UNLEARNING? Or A NEW LEARNING? Neuroscience shows us it’s a new learning → LTD Synaptic plasticity Attentional theories in conditioning If there is no attention to the CS → NO CONDITIONING If CS is presented on its own multiple times before US is given then classical conditioning develops more slowly. The sound → the food The sound multiple times → the food The sound becomes unobtrusive stimulus after a while. The organism learns to ignore sound → habituation DO WE USE CLASSICAL CONDITIONING IN OUR THERAPIES?  AVOIDANCE THERAPY associating (matching) that behavior with an undesirable stimulus to stop the unwanted behavior First use in 1930 in alcohol addiction Administering electric shocks to alcoholics with the smell, taste, and appearance of alcohol Drugs instead of electric shock today A Clockwork Orange Systematic desensitization Replacing an anxiety-provoking response with a comforting one PHOBIAS How can we destroy habits? Treshold Method The stimulus that causes the unwanted behavior should be given little by little and over a long period of time → Systematic desensitization → phobias Making tired/disgusted method All stimuli are given until they are tired of doing the undesirable response.Thus, a new response is developed to the same stimulus. → kids with autism Opposite reaction method A fear-inducing stimulus is given with a more dominant stimulus. E.g. the kid doesn’t want to drink milk → give it with cacao Thanks ☺ Dr. Kübra CELIK Operant/Instrumental conditioning What is the difference? Classical conditioning is out of control Operant conditioning is after the behavior Instrumental Behavior Response: Response is defined as instrumental behavior because the response is instrumental in causing the result. Reinforcer: The result of the behavior Operant behavior: Performing active operations on stimuli. The organism is conditioned by the behaviors it manifests. Action: It arises from the natural movements of the organism. Edward Thorndike (1874-1949) Believed psychology should study behavior, not elements/conscious experiences Developed a theory of learning Connectionism Association between stimuli and responses Connection more likely to form if followed by a reinforcement Response-units: simplest elements of behavior  Law Effect behavior that produces a good outcome becomes associated with a certain situation; when the situation recurs, the behavior is likely to occur again (“stamping in”) likewise, a behavior with a bad outcome is less likely to occur again (“stamping out”) → foundations of operant condtioning https://youtu.be/LsdrhlxTcVY Guthrie and Horton (1946) Law of contiguity The cats showed that whatever movement they made when they moved the pendulum in the first trials, they succeeded in making the same movement to open the door in the following trials and they continued this movement throughout the experiment. B.F. Skinner (1904-1990) Skinner’sbox Operant conditioning Reward- punishment Behavior → Reactive or Operant? What is important in operant learning is the result and the effect of the behavior. It is important that the behavior satisfies a certain need of the organism. Skinner’s Box Skinner’s Box When the animal presses the button inside the cage, a reward is presented that reinforces the behavior. Permanent learning occurs through careful and timely presentation of the reward. Negative reinforcement, on the other hand, causes the behavior not to be repeated or to disappear. Can we explain people’s personality traits by operant conditioning? We measure the response ratio Labyrinths One of the mazes frequently used in operant conditioning studies today is the T maze. The subject is left in the starting box and is expected to move along the tape. When it reaches the end of the band, he has to turn right or left to reach the prize. The measure of learning is the time taken to reach the target box, called latency. Or the error number Can i measure spatial memory with these tests? Can operant conditioning be used to create entirely new behaviors? Formin the behavior → Enabling the same behavior to occur even if the stimulus comes in different forms. I NEED A STRONG REINFORCEMENT IMMEDIATELY If it is too late and other responses intervene, the experimenter may not have fully reinforced the response she was aiming for. It should come right after the reaction. It should be associated with the reaction. How to shape a behavior? 1- Classical conditioning at first ( light or sound and food) 2- Reinforce the animal's crawling in a narrow area close to the arm. 3-Reinforce the animal's standing and similar behaviors 4-Reinforce every movement close to touching or pressing the arm. 5-The bait comes in when the lever is fully pressed. You should give the FULL REINFORCEMENT when fully pressed. As long as pressing the lever continues, shaping continues in fine details. As trials progressed, unnecessary deviations from the behaviors leading to lever pressing result in extinction because they are not reinforced. https://www.youtube.com/watch?v=TtfQlkGwE2U Reinforcement The situation that reinforces the subsequent behavior. A prize We can say that a stimulus reinforces a behavior only after we see that it increases the frequency of that behavior. Primary - Secondary Reinforcers Primary Reinforcer: Satisfying an innate or biologically based need or desire. Similar to unconditioned stimuli in classical conditioning Secondary Reinforcer: Conditional reinforcer that is initially neutral. It becomes a reinforcer by pairing with the primary reinforcer. This is called conditional reinforcement. Instant &Delayed Continuous & Partial Secondary reinforcement- Wolfe’s experiment (1936) Wolfe trained 6 monkeys to get grapes with coins. He must lift weights to obtain the token. Tokens and grapes are have equal value to the animal. Although they were able to turn the tokens into grapes after 1 hour, they lifted obtain the tokens. https://www.youtube.com/watch?v=-KSryJXDpZo Connectivity in 3 Factors According to Skinner, the relation of connectivity is established between 3 factors: - Behavior - Reinforcer - Context (stimulus that initiates behavior) Behavior is a chain of conditioned acts! Reinforcement is obtained by adding together a long series of behaviors. https://www.youtube.com/watch?v=foahTqz7On4 YOU SHOULD BE PATIENT! Determinants of reinforcement - The size of the reinforcer - Hunger and thirst - Response / reinforcer timeframe The size of the reinforcer The reinforcer seals the link between the discriminatory stimulus and the behavior. Re-exposure to the same distinctive stimulus increases the likelihood of the behavior reoccurring. An effective sealing ensures better and permanent learning. Crespi effect → As the reinforcer increases, the behavior increases. Crespi ‘s study (1942) 5 groups of rats were trained to run on the treadmill to obtain bait. Each of the groups was reinforced with different amounts of food (1, 4, 6, 64, 256) After 20 trials: As the amount of food increases, the speed of reaching the target box increases. Hunger and thirst! Animals are deprived of food or water for a while before the experiment. The duration of abstinence is one of the most important factors determining the outcome of operant conditioning. There is a linear relationship between the abstinence period and the performance of the animals in the test boxes. Response- Reinforcer Timeframe The time interval between reaction and reinforcement should be very short. As the time interval between response and reinforcement increases, the response rate of the organism decreases. Capaldi’s study (1978) -Food is used as a reinforcer on the treadmill. 1. group: When they reach the target box, they find the bait ready. 2. Group 2: Rats were kept for 10 seconds before entering the target box. 3. Learning was significantly more difficult in the second group. Biological limitations of operant conditioning Breland’s study The raccoon is trained to pick up the coin from somewhere and carry it a few meters and then drop it into an open box. He does not want to leave the money in the box. Because raccoons often wash their food in a river similar way before eating them. Instinctive deviations!!! Breland’s study (1961) Dancing chickens The casual observer sees a grown bantam chicken emerge from a retaining compartment when the door automatically opens. The chicken walks over about 3 feet, pulls a rubber loop on a small box which starts a repeated auditory stimulus pattern The chicken then steps up onto an 18-inch, slightly raised disc, thereby closing a timer switch, and scratches vigorously, round and round, over the disc for 15 seconds, at the rate of about two scratches per second until the automatic feeder fires in the retaining compartment. The chicken goes into the compartment to eat, thereby auto- [p. 682] matically shutting the door. Requirements removal approach Hull Reinforcement principle: when organisms are deprived of a vital need, a state of arousal or impulse arises that activates the organism to meet this need. Responses that reduce or eliminate the impulse are reinforced. Hunger and thirst! → biological needs Psychological needs for humans → Example? That’s an adaptive process →Impulses drive behavior Homeostasis returns to its original state as impulses decrease. Conditions of learning; Contiguity and impulsedecrease The stimulus elicits a response; If the response also meets the biological need, the bond between the stimulus and the response becomes stronger → Impulse reduction Primary reinforcement → need-fulfilling stimuli Secondary reinforcement → reduces need of stimulants Law effect of Thorndike Habit strength → As the number of reinforced stimuli and responses increases, the strength of the habit also increases. Contrary to this theory Miller and Kessen, 1952 Finding the target box in the T maze 1. group: when they reached the target box, they were reinforced with milk and drank milk.Group 2. 2: milk was directly injected by the experimenter through a tiny tube extending into the stomachs of the animals. 3. 3rd group: saline was injected into their stomachs instead of milk Learning status Drinking milk normally > milk injected into the stomach > saline injected into the stomach Contrary to this theory Sheffield 1951 Male rats were trained to reach the target box on the treadmill. The behavior of reaching the target box was reinforced by allowing mating with female rats. However, Animals not allowed to ejaculate , by the experimenterremoved from the labyrinth. Despite this, the animals learned their response to reaching the target box very quickly. These findings are in contrast to the view that reinforcers remove impulses. Reinforcers that increase rather than decrease the level of arousal caused by the drive WHAT IS THE MOST POWERFUL REINFORCER FOR US IN DAILY LIVES? Stimuli or situations that have a reinforcing effect do not always satisfy a certain need of the organism. → MONEY? Premack Principle It proposes a response-reaction link instead of a response-reinforcer link. Under certain conditions, some reactions or behaviors are preferred over others. A reinforcer is not a reinforcer in all circumstances. → IF I’M NOT HUNGRY One's own behavior can be used as a reinforcer. Positive Reinforcement A pleasurable stimulus followed by an operant response External reinforcers: provided from the external environment Internal Reinforcers: From internal positive emotions provided Negative Reinforcement Removal of a repulsive stimulus in the environment For example; In the Skinner box, the rats are constantly given an annoying sound. When the animal presses the lever, this sound stops for a while. The disappearance of the annoying sound reinforces the lever pressing behavior of the rats. Positive Punishment Giving the disturbing stimulus to the environment is a positive punishment. For example, a student who does not do her homework is scolded by her teacher Negative Punishment Removing a pleasant stimulus from the environment is a negative punishment. For example; Prohibiting a student who does not do his homework from playing computer games in the evening. Types of opearant conditioning Yellows increase behavior; blues decreases Reward Pathways and Motivational Mechanisms Regulation of behavior Dopamine (DA) Noradrenaline(NA) Serotonine (5-HT) Adrenaline (A) Histamin Adenozine?? Nöropeptides?? Glutamate?? Dopamine Pathways: Reward, pleasure, feeling good motor functions, decision making PFC Hippocampus Nucleus accumbens Ventral tegmental alan Raphe Serotonine Pathways: humor, memory, sleep, cognition You need to active this pathway for operant conditioning! Activities that stimulate and activate the reward pathwayFood, water, sex, exercise, exciting activities or drugs.. When reward centers are stimulated in humans, they have described it as "relieving tension, a calming, relaxing feeling".  Reward Pathway Areas PFC Thalamus Nucleus Ventral Accumbens Tegmental (NAc) Alan (VTA) Locus Coeruleus Avoidance conditioning A reinforcing stimulus is an unpleasant or repulsive stimulus. Avoidance conditioning increases the emergence of operant behavior. Punishment mechanisms result in the suppression of the operant response. In avoidance, safety is achieved by doing something → active avoidance Safety in punishment is achieved by doing nothing → passive avoidance Examples: Extending your hand towards the door when approaching a door Clinging to stair railings slowing down in traffic Passive avoidance There are experimental protocols designed as not reaching the reward or avoiding the punishment. For example, if there is an experimental setup with 2 sections, one dark and the other bright, the rat will prefer to go to the dark. What if we give shock in the dark side? Another example is when a starving rat learns not to reach for food. The animal receives an electric shock when reaching for the food, so it learns not to reach for the food even if it is hungry.  Active avoidance In an experimental environment arranged according to shock, there is another environment or section where the animal will escape from receiving shock. When they receive the shock the pole is the only place where animal can escape. The electric shock is paired with a neutral stimulus (sound or light). The expected response from the animal is to climb the pole without receiving the electric shock when it hears the sound or sees the light. Distinctive Avoidance Avoidance trial: If the participant responds to avoidance during the conditioned stimulus (before the unconditioned stimulus comes), the CS is turned off and the US is not given. Attempt to escape: If the participant does not react during CS-US, the shock is given until the appropriate response occurs. Non-Distinctive Avoidance (free No obvious excitatory stimulus is used and there are no discrete trials. operant avoidance) The participant reacts whenever he wants. A shock is presented depending on whether the participant engages in avoidance behavior. A brief shock comes every 15 seconds when the participant does not react. It creates a safe time (30 seconds) that the shock does not come when the participant reacts. Learned helplessness Seligman and Meier (1967) In the first phase of this experiment with dogs, each dog was assigned one of the following three conditions. 1) Non-avoidable condition: The dogs were exposed to shock for a period of time, but the dogs were not allowed to escape the shock. 2) Avoidable condition: In this condition, the dogs were given a shock, but the dogs were able to escape the shock given to them by pressing a button. In addition, when the dogs in this condition pressed the button, they were able to put an end to the shock exposure of the dogs that could not escape from the shock. 3) No shock condition: These dogs were never exposed to shock, they just waited for the first phase of the experiment to finish. Learned helplessness At irregular intervals, the animals were given a 50-second electric shock through the grids at the bottom of the test box, after a 10-second warning light. The shock ceased when the animals jumped over the barrier to the other side of the test box during the shock. (Escape) If they jump while the warning light is on before the shock, the shock has not been delivered. (Avoidance) 1. Group : They are not allowed to escape in this condition 2. Group: They are allowed to escape In this set up → 1st group can never learn how to escape even they are able to afterwards Forced swimming test https://www.youtube.com/watch?v=LZn5SY55RKw Recovery of learned helplessness However Animals with learned helplessness are more likely to respond more easily when they are guided to give the right response. The learned helplessnes may gradually disappear Reinforcements Patterns Reinforcement scheme: The program or rule that decides the formation of the response after reinforcement. Continuous Reinforcement: Reinforcement occurs whenever a desired response occurs. Intermittent Reinforcement: The desired response is reinforced once in a while, not every time it occurs. Ratio Patterns: Reinforcing a certain number of responses Reinforcement based on the number of responses the organism performs Fixed Ratio pattern Variable Ratio pattern Fixed Ratio Pattern The number of responses that the organism must elicit to obtain the reinforcer is constant in each trial. High and consistent response speed A pause after reinforcement For example, piece rate wages paid to workers. Variable Ratio Reinforcement is given after an unpredictable number of responses. The greater the number of responses, the higher the probability that the reinforcement will be acquired. The reinforcement of the next reaction is all about luck. Intermittent Patterns: Reinforcing the initial response after a while Reinforcement: Depends on the initial reaction after a certain time has passed. Fixed range : Reinforcement takes a certain amount of time to appear. And this time interval must be the same For ex: the salary Variable range :The time it takes for the organism to obtain a reinforcer after the previous reinforcer varies with each trial. Which one is the best? In Reynold's (1975) experiment, one of the two pigeons was given a variable interval reinforcer and the other a variable ratio reinforcer. Although both pigeons received the same amount of reinforcement as a result, the response rate of the variable ratio pattern pigeon was higher. Concurrent setups It includes at least two response alternatives. Both options are also readily available. The effort required for each response alternative is equal, The reinforcer is the same. Easy to switch between response alternatives Equivalence law (Hernstein, 1961) The proportional relationship observed between the preference distribution of organisms for alternative responses and the probability of reinforcement of these responses. → Can we explain all of our behaviors with that? Three pigeons are trained to peck the 2 buttons on the box. The reaction to the left button is reinforced after 135 seconds, and the reaction to the right button is reinforced after 270 seconds. → so which one has the higher response? The greater the probability of reinforcement, the greater the response!! The effect of delay in reinforcement Rachlin and Green (1972): A study with pigeons: if it pecks the left button, she will get bait after 2 seconds, while if it pecks the right button, she will take the bait after 4 seconds. The pigeon pecking the 2nd button gets twice as much as it pecks the 1st button. However, in 95% of the trials, the pigeons pecked the 1st button. They preferred half rather than waiting for 4 seconds for a larger amount of feed. R1 −−−−−→ 2 seconds of food R2 −−−−−−−−−−−−→ 4 seconds of food Other reinforcement setups Reinforcing Low Rate Responses: For the reaction to be reinforced, a minimum period of time must pass after the previous reinforcement and the organism must not react during this time. (For example, in the 20-second schedule, the organism should not react for 20 seconds after receiving a reinforcer.) Reinforcing high-rate responses: In order to obtain a reinforcer, the organism must give a minimum number of responses in a limited time. Reinforcing alternative responses: Before the organism reactstime spent is reinforced. (elimination of finger sucking, nail biting, etc. habits) Theoretical Discussions on Reinforcement Schemes Break Time: Appears in fixed-rate reinforcement schemes. One of the most important determinants of the break time is the number of reactions the organism must give for the next reinforcer. As the number of responses to be given increases, the time taken before the break also increases. Punishments Do you think punishments are effective as much as reinforcers? Which one is more strong to shape behavior ? Skinner’s study First stage: the rats were taught the lever-pressing behavior to get bait. Second stage: This behavior was extinguished by cutting the bait in the extinction stage. During the extinction process, the rats were divided into two groups: the normal extinction group and the punishment group. Third stage: The rats greatly reduced responsiveness during punishment. However, after the penalty was removed, they started to increase the number of reactions again. Severity of punishment Boe and Churc (1967) First stage: Rats were taught lever pressing behavior. Second stage: This behavior is penalized.0 In the range of 220 V Third stage result: Mild shock slightly decreased the lever pressing behavior, but as the shock amount increased, the suppression behavior increased. Alternatives for punishment The circumstances that lead to the undesirable behavior can change, so the behavior can also change. If the undesirable behavior is a result of the child's developmental period, such behavioral methods can be used. The most effective alternative method is extinction. Ignoring unwanted behavior. Behavior continues as long as it is reinforced, whether positive or negative. How to use reinforcers? 1- Specify quantity and quality of the behavior? 2 -Behaviors that do not occur spontaneously should be reinforced. → it shouldnt exist before 3- find your best reinforcer 4- is your reinforcer going to be a good one after the response? 5- reinforce the complex behavior step by step 6- when the behavior occurs, remove the reinforcer Strategies to Reduce Undesirable Behaviors - Extinction of responses - Unconditional reinforcement - Reinforcing other behaviors: Applied Behavior Analysis (ABA) It is a method used to overcome solid problem behavior. Problem behaviors are a product of past and present reaction-outcome conditioning. Behavioral methods used: Reinforcement Shaping Clue Extinction Punishment What is common in classical and operant conditioning? Spontaneous recovery, generalization, discrimination, and secondary reinforcement phenomena are common. What is different? There is no unique unconditioned stimulus to cause a response. The subject is free to demonstrate the behavior at any time. Thanks for listening! Neurobiology of Learning and Memory DR. KÜBRA CELIK Learning and Memory Learning to gain knowledge as a result of experience and to be able to store this knowledge An increase in the likelihood of a response to a stimulus. Rewards, punishment and environmental factors Memory is the permanent storage of learned information and its retrieval when necessary. The brain processes, stores, and retrieves information in different ways in accordance with needs. Memory Classification by time Short-term Long-term Classification by the nature of information Implicit Explicit  INFORMATION Sensory Memory Short Extinction