Psy review - Abnormal Psychology with David Sitt. Chapter 1 to 5 PDF

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Abnormal Psychology with David Sitt. Chapter 1 to 5...

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Chapter 1

The users of every type of drug include some who have tried it but won’t use it again, some who use it infrequently, some who use it more often but in small amounts, and some who use frequently and in greater amounts. This is as true for users of heroin and crack cocaine as it is for users of alcohol and marijuana. No drug is either entirely good or bad, and every drug has multiple effects. The size and type of effect depends on the dose of the drug and the user’s history and expectations. Deviant drug use includes those forms of drug use not considered either normal or acceptable by the society at large. Drug misuse is using a drug in a way that was not intended by its manufacturer. Drug abuse is drug use that causes problems. (If frequent and serious, then a diagnosis of substance-use disorder is applied.) Drug dependence involves using the substance more often or in greater amounts than the user intended, and having difficulty stop- ping or cutting down on its use. Among American college students, almost 70 percent can be considered current users of alcohol, less than 20 percent current smokers of tobacco cigarettes, or marijuana, and less than 2 percent current users of cocaine. Both alcohol and illicit drug use reached an apparent peak around 1980, then de- creased until the early 1990s, with a slower increase after that. Current rates of use are lower than at the peak. Adolescents who use illicit drugs (mostly marijuana) are more likely to know adults who use drugs, less likely to believe that their parents would object to their drug use, less likely to see their parents as a source of social support, more likely to have friends who use drugs, less likely to be religious, and more likely to have academic problems.  A typical progression of drug use starts with cigarettes and alcohol, then marijuana, then other drugs such as amphetamines, cocaine, or heroin. However, there is no evidence that using one of the “gateway” substances causes one to escalate to more deviant forms of drug use.  People may use illicit or dangerous drugs for a variety of reasons: They may be part of a deviant subculture, they may be signaling their rebellion, they may find the effects of the drugs to be reinforcing, or they may be seeking an altered state of consciousness. The specific types of drugs and the ways they are used will be influenced by the user’s social and physical environment. If dependence develops, then these environmental factors may begin to have less influence.  Chapter 2

American society has changed from being one that tolerated a wide variety of individual drug use to being one that attempts strict control over some types of drugs. This has occurred in response to social concerns about drug toxicity, dependence potential, and drug-related crime and violence.  Toxicity can refer either to physiological poisoning or to dangerous disruption of behavior. Also, we can distinguish acute toxicity, resulting from the presence of too much of a drug, from chronic toxicity, which results from long-term exposure to a drug.  Heroin and cocaine have high risks of toxicity per user, but their overall public health impact is low

compared to tobacco and alcohol.  Prescription drugs are also important contributors to overall drug toxicity figures.  Drug dependence does not depend solely on the drug itself, but the use of some drugs is more likely to result in dependence than is the use of other drugs. The idea that opioid drugs or marijuana can produce violent criminality in their users is an old and largely discredited idea. Opioid users seem to engage in crimes mainly to obtain money, not because they are made more criminal by the drugs they take. One drug that is widely accepted as contributing to crimes and violence is alcohol. There are more than 1.5 million arrests each year in the United States for drug- law violations. Laws that have been developed to control drug use have a legitimate social purpose, which is to protect society from the dangers caused by some types of drug use. Whether these dangers have always been viewed rationally, and whether the laws have had their intended results, can be better judged after we have learned more about the drugs and the history of their regulation. Chapter 3

In the early 1900s, two federal laws were passed on which our current drug regulations are based.  The 1906 Pure Food and Drugs Act, requiring accurate labeling, was amended in 1938 to require safety testing and in 1962 to require testing for effectiveness.  A company wishing to market a new drug must first test it on animals, then file an IND. After a threephase sequence of human testing, the company can file the NDA.  The 1914 Harrison Act regulated the sale of opioids and cocaine. The Harrison Act was a tax law, but after 1919 it was enforced as a prohibition against providing drugs to dependent users. As drugs became more scarce and their price rose on the illicit market, the illicit market grew. Harsher penalties and in- creased enforcement efforts, which were the primary strategies of Commissioner of Narcotics Harry Anslinger, failed to reverse the trend. Marijuana was added to the list of con- trolled drugs in 1937, and in 1965 amphetamines, barbiturates, and hallucinogens were also brought under federal control. The Controlled Substances Act of 1970 first provided for direct federal regulation of drugs, not through the pretense of taxing their sale. Controlled substances are placed on one of five schedules, depending on medical use and dependence potential. Amendments in 1988 were aimed at increasing pressure on users, as well as on criminal organizations and money laundering.

Federal support for drug screening began in the military and has since spread to other federal agencies, nonfederal transportation workers, and many private employers. Current federal enforcement efforts involve thousands of federal employees and include activities in other countries, along our borders, and within the United States. Most states have adopted some version of the DEA’s recommended Uniform Con- trolled Substances Act. Federal, state, and local enforcement limits the supply of drugs and keeps their prices high, but the high prices attract more smugglers and dealers. It will never be possible to eliminate illicit drugs. Chapter 4

Chemical signals in the body are import- ant for maintaining homeostasis. The two types of chemical signals are hormones and neurotransmitters.  Neurotransmitters act over brief time periods and very small distances because they are released into the synapse between neurons and are then rapidly cleared from the synapse.  Receptors are specialized structures that recognize neurotransmitter molecules and, when activated, cause a change in the electrical activity of the neuron.  The nervous system can be roughly divided into the central nervous system, the somatic system, and the autonomic system. The autonomic system, with its sympathetic and parasympathetic branches, is important because so many psychoactive drugs also have autonomic influences on heart rate, blood pressure, and so on. Specialized chemical pathways contain the important neurotransmitter dopamine, acetylcholine, norepinephrine, and serotonin. The nigrostriatal dopamine system is damaged in Parkinson’s disease, leading to muscular rigidity and tremors. The mesolimbic dopamine system is thought by many to be a critical pathway for the dependence produced by many drugs. The neurotransmitter GABA is inhibitory and the neurotransmitter glutamate is excitatory; both are found in most parts of the brain. The life cycle of a typical neurotransmitter chemical involves uptake of precursors, synthesis of the transmitter, storage in vesicles, release into the synapse, interaction with the receptor, reuptake into the releasing neuron, and metabolism by enzymes. Psychoactive drugs act either by altering the availability of a neurotransmitter at the synapse or by directly interacting with a neurotransmitter receptor. Chapter 5

Most drugs are derived directly or indirectly from plants. The legal pharmaceutical industry is one of the largest and most profitable industries in the United States. Brand names belong to one company; the generic name for a chemical may be used by many companies. Most psychoactive drugs can be categorized as stimulants, depressants, opioids, hallucinogens, or a psychotherapeutic agent. Drugs can be identified by the appearance of commercial tablets or capsules, in some cases by the packaging or appearance of illicit drugs, or by a variety of chemical assays. Specific drug effects are related to the con- centration of the chemical; nonspecific effects can also be called placebo effects. Because each drug is capable of producing many effects, many dose-effect relationships can be studied for any given drug. The ratio of LD50 to ED50 is called the therapeutic index and is one indication of the relative safety of a drug for a particular use or effect.  The potency of a drug is the amount needed to produce an effect, not the importance of the effect.  The time course of a drug’s effect is influenced by many factors, including route of administration, protein binding in the blood, and rate of elimination.  Virtually all psychoactive drugs have relatively specific effects on one neurotransmitter system or more, either through altering availability of the transmitter or by interacting with its receptor.  The liver microsomal enzyme system is important for drug deactivation and for some types of drug interactions.  Drug tolerance can result from changes in distribution and elimination, from behavioral adaptations, or from changes in the responsiveness of the nervous system caused by compensatory (homeostatic) mechanisms. Physical dependence (withdrawal) can be a consequence of this last type of tolerance. ...