5 Chapter A. Principal Abused Drugs and Their Effects a. The drugs that people use recreationally are termed psychoactive. i. Psychoactive drugs are chemical substances that modify mental, emotional, or behavioral functioning. ii. Narcotics or opiates are drugs derived from opium that are capable of relieving pain. 1. Heroin, morphine, codeine, Demerol, and methadone 2. Produce euphoria; "Who cares?" quality iii. Sedatives are sleep inducing drugs that tend to decrease central nervous system activation and behavioral activity. 1. The most widely abused sedatives are barbiturates 2. Euphoria similar to drinking alcohol. iv. Stimulants are drugs that tend to increase central nervous system activation and behavioral activity. 1. Cocaine: Natural, produces a briefer high than amphetamines. 2. Amphetamines (speed) 3. Produce a euphoria that is different from narcotics or sedatives; "I can conquer the world!" feeling. v. Hallucinogens are a diverse group of drugs that have powerful effects on mental and emotional functioning, marked most prominently by distortions in sensory and perceptual experience. 1. LSD, mescaline, and psilocybin. vi. Cannabis is the hemp plant from which marijuana, hashish, and THC are derived. vii. Alcohol encompasses a variety of beverages containing ethyl alcohol. 1. Most widely used recreational drug in our society. viii. MDMA, or "ecstasy" is a compound drug that is related to both amphetamines and hallucinogens, especially mescaline. * Look at Table 5.2 on pg. 157B B. Factors Influencing Drug Effects a. Drug effects can vary from person to person i. It depends on the user's age, mood, motivation, personality, previous experience with the drug, body weight, and physiology. ii. Expectations can influence the user's perception of a drug's effects iii. Tolerance refers to a progressive decrease in a person's responsiveness to a drug as a result of continued use. C. Mechanisms of Drug Action a. Psychoactive drugs work primarily by altering neurotransmitter activity in the brain. i. Neurotransmitters are chemicals that transmit signals between neurons at junctions called synapses.
ii. Many theorists believe that virtually all abused drugs eventually increase activity in a particular neural pathway, called the mesolimbic dopamine pathway (reward pathway). See Figure 5.11 on pg. 159. D. Drug Dependence a. Physical dependence exists when a person must continue to take a drug to avoid withdrawal illness. i. Narcotics, sedatives, alcohol, and occasionally stimulants. b. Psychological dependence exists when a person must continue to take a drug to satisfy intense mental and emotional craving. i. This dependence is possible with all rec. drugs, but seems rare for hallucinogens. E. Drugs and Health a. Overdose i. CNS depressants (Sedatives, narcotics, and alcohol) carry the greatest risk of overdose. Many overdoses involve lethal combos of CNS depressants. b. Tissue damage (Direct Effect) c. Synergistic Effect: the drugs create an effect greater than would be expected if we
summed their effects individually
Chapter 6 Learning is any relatively durable change in behavior or knowledge that is due to experience. Conditioning involves learning associations between events that occur in an organism's environment (eating chicken and having success hitting a baseball is one example). Phobias are irrational fears of specific objects or situations. I. Classical Conditioning: This is a type of learning in which a stimulus acquires the capacity to evoke a response that was originally evoked by another stimulus. It is sometimes Pavlovian conditioning because Ivan Pavlov first described it. A. Terminology and Procedures a. Unconditioned Association (bond between meat powder and salivation) i. The unconditioned stimulus (UCS) is a stimulus that evokes an unconditioned response without previous conditioning. ii. The unconditioned response (UCR) is an unlearned reaction to an unconditioned stimulus that occurs without previous conditioning. b. Conditioned Association (bond between the tone and salivation) i. The conditioned stimulus (CS) is a previously neutral stimulus that has, through conditioning, acquired the capacity to evoke a conditioned response. ii. The conditioned response (CR) is a learned reaction to a conditioned stimulus that occurs because of previous conditioning. iii. The unconditioned response and the conditioned response are virtually the same behavior.
c. A trial in classical conditioning consists of any presentation of a stimulus or pair of stimuli. B. Basic Processes in Classical Conditioning a. Acquisition refers to the initial stage of learning something. i. Pavlov theorized that the acquisition of a conditioned response depends on stimulus contiguity. Stimuli are contiguous if they occur together in time and space. It is important, but contiguity alone doesn't automatically produce conditioning. b. Extinction is the gradual weakening and disappearance of a conditioned response tendency. i. The consistent presentation of the conditioned stimulus alone without the unconditioned stimulus leads to extinction. c. Spontaneous recovery is the reappearance of an extinguished response after a period of nonexposure to the conditioned stimulus. d. Stimulus generalization when occurs an organism that has learned a response to a specific stimulus responds in the same way to new stimuli that are similar to the original stimulus. i. The basic law governing generalization is this: The more similar new stimuli are to the original CS, the greater the likelihood of generalization. e. Stimulus discrimination occurs when an organism that has learned a response to a specific stimulus does not respond in the same way to new stimuli that are similar to the original stimulus. i. The basic law governing discrimination is this: The less similar new stimuli are to the original CS, the greater the likelihood (and ease) of discrimination. f. Higher order conditioning is when a conditioned stimulus functions as if it were an unconditioned stimulus. II. Operant Conditioning: Is a form of learning in which voluntary responses come to be controlled by their consequences. The fundamental principle of operant conditioning is that organisms tend to repeat those responses that are followed by favorable consequences. Reinforcement occurs when an event following a response increases an organism's tendency to make that response. A response is strengthened because it leads to rewarding consequences. A. Terminology and Procedures a. A Skinner box is a small enclosure in which an animal can make a specific response that is systematically recorded while the consequences of the response are controlled. b. Reinforcement contingencies are the circumstances or rules that determine whether responses lead to the presentation of reinforcers. c. The cumulative recorder creates a graphic record of responding and reinforcement in a Skinner box as a function of time. i. A rapid response rate produces a steep slope. B. Basic Processes in Operant Conditioning a. Acquisition is still the formation of a new response tendency.
b. Shaping: the reinforcement of closer and closer approximations of a desired response. c. In operant conditioning extinction refers to the gradual weakening and disappearance of a response tendency because the response is no longer followed by reinforcement. i. Resistance to extinction occurs when an organism continues to make a response after delivery of the reinforcer for it has been terminated. d. Discriminative stimuli are cues that influence operant behavior by indicating the probable consequences (reinforcement or nonreinforcement) of a response. C. Reinforcement and Punishment a. The central process in reinforcement is the strengthening of a response tendency. b. Primary reinforcers are events that are inherently reinforcing because they satisfy biological needs. c. Secondary or conditioned reinforcers are events that acquire reinforcing qualities by being associated with primary reinforcers. d. A schedule of reinforcement is a specific pattern of presentation of reinforcers over time. i. The simplest pattern is continuous reinforcement which occurs when every instance of a designated response is reinforced. ii. Intermittent reinforcement occurs when a designated response is reinforced only some of the time. e. In a fixed ratio (FR) schedule, the reinforcer is given after a fixed number of nonreinforced responses. i. In a variable ratio (VR) schedule the reinforcer is given after a variable number of nonreinforced responses. ii. In a fixed interval (FI) schedule, the reinforcer is given for the first response that occurs after a fixed time interval has elapsed. iii. In a variable interval (VI) schedule, the reinforcer is given for the first response after a variable time interval has elapsed. The interval length varies around a predetermined average. iv. Ratio schedules tend to produce more rapid responding than interval schedules. Variable schedules tend to generate steadier response rates and greater resistance to extinction then their fixed counterparts. v. Look at 6.12 and 6.13 on pg. 184 vi. Positive reinforcement occurs when a response is strengthened because it is followed by the presentation of a rewarding stimulus. vii. Negative reinforcement occurs when a response is strengthened because it is followed by the removal of an unpleasant stimulus. viii. In escape learning, an organism acquires a response that decreases or ends some unpleasant stimulation. ix. In avoidance learning an organism requires a response that prevents some unpleasant stimulation from occurring. x. Punishment occurs when an event following a response weakens the tendency to make that response.
i. Presentation of an unpleasant stimulus or removal of a rewarding stimulus. D. One biological constraint on learning is instinctive drift, which occurs when an animal's innate response tendencies interfere with conditioning processes. E. Latent learning is learning that is not apparent from behavior when it first occurs. a. First this suggested that learning can take place in the absence of reinforcement. b. Second it suggested that the rats who displayed latent learning had formed a cognitive map of the maze. III. Observational Learning: This occurs when an organism's responding is influenced by the observation of others, who are called models. A. Basic Processes a. Attention, Retention, Reproduction, Motivation Chapter 7 Encoding (getting information in): Storage (maintaining it): Retrieval (getting it out):