Respond in an appropriate manner to the sensory inputs. Examples of depressants include alcohol, opioids (including prescription drugs such as morphine and street drugs like heroin), and tranquilizers. Some also cause euphoria,. How do psychoactive drugs affect the central nervous system? Title: Psychopharmacology Of Widely Available Psychoactive Natural Products (R03) Announcement Type This is a reissue of PA-06-323 , which was previously released April 5, 2006. [Solved] --6 classifications of psychoactive drugs-- What are these Psychoactive Drugs Affect the Central Nervous System. The methylated version of amphetamine, methamphetamine (meth or crank), is currently favored by users, partly because it is available in ampoules ready for use by injection (Csaky & Barnes, 1984). The drugs that produce the most extreme alteration of consciousness are the hallucinogens, psychoactive drugs that alter sensation and perception and that may create hallucinations. Morphine and heroin are stronger, more addictive drugs derived from opium, while codeine is a weaker analgesic and less addictive member of the opiate family. As you can see in Table 5.1 Psychoactive Drugs by Class, the four primary classes of psychoactive drugs are stimulants, depressants, opioids, and hallucinogens. Nicotine, which people can find in smoked and chewed tobacco products, is a stimulant and depressant. These drugs operate by affecting neurons (nerve cells) in the CNS, which leads to symptoms such as drowsiness, relaxation, decreased inhibition, anesthesia, sleep, coma, and even death. Gable, R. (2004). After all, stimulant medications are powerful psychoactive substances, which are prohibited to use without medical prescriptions, under federal drug laws. You can learn more about how we ensure our content is accurate and current by reading our. PDF Basu and Basu. Int Arch Addict Res Med 2015, 1:1 SS 21 nternational The hallucinogens may produce striking changes in perception through one or more of the senses. How do stimulant and depressant drugs affect the nervous system Dissociative drugs are believed to disrupt the action of glutamate, a brain chemical that is involved with memories, cognition, emotions, and how people perceive pain. Neuropsychopharmacology, 26(4), 479488. How Viagra became a new 'tool' for young men, Ankylosing Spondylitis Pain: Fact or Fiction, Substance Abuse and Mental Health Services Administration (SAMHSA), https://www.cdc.gov/niosh/emres/longhourstraining/caffeine.html, https://nida.nih.gov/drug-topics/commonly-used-drugs-charts, https://www.niaaa.nih.gov/publications/brochures-and-fact-sheets/hangovers, https://nida.nih.gov/publications/research-reports/hallucinogens-dissociative-drugs/how-do-hallucinogens-lsd-psilocybin-peyote-dmt-ayahuasca-affect-brain-body, https://www.ncbi.nlm.nih.gov/books/NBK556103/, https://nida.nih.gov/publications/drugfacts/mdma-ecstasymolly, https://www.cancer.gov/publications/dictionaries/cancer-terms/def/psychoactive-substance, https://veterans.smokefree.gov/nicotine-addiction/reasons-people-smoke, https://www.mind.org.uk/information-support/types-of-mental-health-problems/drugs-recreational-drugs-alcohol/types-of-recreational-drug/, https://nida.nih.gov/publications/research-reports/marijuana/what-are-marijuana-effects, https://nida.nih.gov/publications/drugfacts/prescription-opioids, https://nida.nih.gov/publications/drugfacts/prescription-stimulants, https://nida.nih.gov/publications/research-reports/heroin/what-are-immediate-short-term-effects-heroin-use, https://nida.nih.gov/publications/research-reports/cocaine/what-are-short-term-effects-cocaine-use, https://nida.nih.gov/publications/drugfacts/fentanyl, Cardiovascular health: Insomnia linked to greater risk of heart attack. Vaughan, Corbin, and Fromme (2009) found that college students who expressed positive academic values and strong ambitions had less alcohol consumption and alcohol-related problems, and cigarette smoking has declined more among youth from wealthier and more educated homes than among those from lower socioeconomic backgrounds (Johnston, OMalley, Bachman, & Schulenberg, 2004). Find out more about the health risks of smoking. Cocaine has a safety ratio of 15, making it a very dangerous recreational drug. However, when there is a dopamine surge, people may become nervous, irritable, aggressive, or paranoid. Regular cocaine abuse can lead to paranoia and negatively impact functions of the central nervous system, causing cardiac arrhythmias, sudden cardiac arrest, ischemic heart conditions, a respiratory syndrome unique to snorting to cocaine, hypertension, convulsions, stroke, and death, the DEA warns. Most CNS depressants act on the brain by increasing activity of gamma-aminobutyric acid (GABA), a chemical that inhibits brain activity. Graham, K., Osgood, D. W., Wells, S., & Stockwell, T. (2006). It exhausts the systemNeurons exhaust their ability to communicate.Once the drugs are goneShort-term: user feels the opposite of the drugRebound effect while the neurons recover.Over time: the brain adaptsReduces the number of dopamine receptor sitesProduces less dopamineResult: toleranceUser needs larger dose to feel the pleasure rush.Maybe . When people go on a "trip," they are prone to seeing or hearing things that aren't really there. Restlessness, irritability, headache and body aches, tremors, nausea, vomiting, and severe abdominal pain, All side effects of morphine but about twice as addictive as morphine. Over time, an individual can develop a tolerance to or dependency on alcohol. 39 Drugs and Altered Consciousness - Dalhousie University However, moderate use can cause irritability, depression, sleep problems, and anxiety. tolerance Continued use of psychoactive drugs leads to.. tolerance the need to take increasing amounts of a drug to get the same effect tolerance Common brand names of prescription opioids include OxyContin and Percocet. How Drugs Affect the Brain & Central Nervous System MDMA interferes with the way the brain processes information and stores memories, and with long-term use, these cognitive issues can become more pronounced. The faster the drug is absorbed into the bloodstream and delivered to the brain, the more intense the high. Until it was banned in the United States under the Marijuana Tax Act of 1938, it was widely used for medical purposes. The narrowing of attention that occurs when we are intoxicated also prevents us from being cognizant of the negative outcomes of our aggression. Caffeine is the most widely consumed central-nervous-system stimulant. MDMA also affects the temperature-regulating mechanisms of the brain, so in high doses, and especially when combined with vigorous physical activity like dancing, it can cause the body to become so drastically overheated that users can literally burn up and die from hyperthermia and dehydration. If we expect that alcohol will make us more aggressive, then we tend to become more aggressive when we drink. Psychoactive drugs affect the body's central nervous system. perception, consciousness, cognition or mood and emotions. Because the participants do not have precise information about the probability of each balloon exploding, and because each balloon is programmed to explode after a different number of pumps, the participants have to determine how much to pump up the balloon. In the period 1991 to 1997, the percentage of 12th-graders who responded that they perceived great harm in regular marijuana use declined from 79% to 58%, while annual use of marijuana in this group rose from 24% to 39% (Johnston et al., 2004). Does Your Health Insurance Cover Treatment? Many depressant medications also have the potential to be addictive. In contrast to stimulants, which work to increase neural activity, a depressant acts to slow down consciousness. The American Journal of Drug and Alcohol Abuse, 32(2), 275285. Barbiturate intoxication and overdose. In general, hallucinogens are not considered to be addictive; however, there may be residual effects of their abuse. Comparison of acute lethal toxicity of commonly abused psychoactive substances. The brain stem controls life-sustaining functions, including sleeping, breathing, and heart rate, while the limbic system holds the brains reward circuitry and helps to control emotions and the ability to feel happiness. New York, NY: Plenum Press; Bushman, B. J., & Cooper, H. M. (1990). Act. Psychology- CH. 4 Psychoactive Drugs Flashcards | Quizlet Central nervous system depressants are used to treat a number of different disorders, including: insomnia, anxiety, panic attacks, stress, sleep disorders, pain, and seizures. Furthermore, as we will see in the next section, there are many other enjoyable ways to alter consciousness that are safer. Some psychoactive drugs are agonists, which mimic the operation of a neurotransmitter; some are antagonists, which block the action of a neurotransmitter; and some work by blocking the reuptake of neurotransmitters at the synapse. 13.4 Evaluating Treatment and Prevention: What Works? Altering Consciousness With Psychoactive Drugs | Open Textbooks for Because more of these neurotransmitters remain active in the brain, the result is an increase in the activity of the sympathetic division of the autonomic nervous system (ANS). Meth also significantly damages the dopamine system in the brain, which can cause problems with memory and learning, movement, and emotional regulation issues. Drunk in public, drunk in private: The relationship between college students, drinking environments and alcohol consumption. Their effect on the central nervous system causes an individual to experience changes, including: These changes can be helpful or desirable, but psychoactive drugs can also yield unwanted effects. 7 Drug Categories - International Association of Chiefs of Police Stimulants increase the activity of the central nervous system, making the person more alert and aroused. Supporting the hypothesis that risk tolerance is related to smoking, Lejuez et al. Drug use by U.S. Army enlisted men in Vietnam: A follow-up on their return home. The phrase psychoactive drug often refers to illegal substances, such as lysergic acid diethylamide (LSD), heroin, and cocaine. The central nervous system controls both voluntary movements, such as those involved in walking and in speech, and involuntary movements, such as breathing and reflex actions. Examples include amphetamines (such as Adderall), cocaine, and caffeine. Hallucinogens like mushrooms, LSD, DMT, and ayahuasca affect the brain differently. b. Alterations of moods, distortions of reality and sensory perceptions, and seeing, hearing, or feeling things that are not there are common side effects of drug-induced psychosis, or a trip. Some people may feel euphoric and have what they consider to be a spiritual awakening while others may suffer from panic, paranoia, anxiety, and despair, which are side effects of a bad trip. Hallucinogenic drugs can be unpredictable and affect each user differently. central nervous system, system of nerve tissue in vertebrates that consists of the brain and spinal cord. Amphetamines are a type of stimulant. When someone abuses marijuana, impaired motor skills, mood alterations, distorted time and sensory perception, decreased memory, and trouble thinking clearly and solving problems are all common short-term side effects. The most common psychoactive drugs can roughly be divided into four groups: Depressants, such as alcohol, sedatives/hypnotics and volatile solvents, that diminish the activity of the central nervous system. Psychoactive drugs are chemicals that change our state of consciousness. They can come in the form of prescription medications to treat attention deficit hyperactivity disorder or narcolepsy, with the brand names Adderall or Dexedrine. Research has found three main ways that certain drugs, such as methamphetamine, can cause physiological and biochemical damage to the brain and nervous system. Some of these risks include heart issues, addiction, worsening symptoms of mental illness, and death. Most receptors are specifically tuned to accept only one type of neurotransmitter key. how do psychoactive drugs affect the nervous system? - VDOCUMENTS This increased activity reduces brain activity, resulting in the relaxing effect of these drugs. These drugs are called opioids partly because they activate the opioid receptors on nerve cells, mimicking the effects of pain-relieving chemicals that would otherwise be produced naturally. Some depressants include alcohol, barbiturates and benzodiazepines. Psychoactive drugs may be legal prescription medications (e.g., codeine and morphine), legal nonprescription drugs (e.g., alcohol and tobacco), or illegal drugs (cocaine and LSD). Continued use of stimulants may result in severe psychological depression. They can cause delays in processing commands to the body. Psychoactive Drugs Drugs that change a user's perspective of reality are called hallucinogens. NIDA warns that marijuana use in adolescence, and continued on into adulthood, may result in a loss of IQ points that are not recoverable even with abstinence. Ecstasy, also known as Molly or by its chemical name, MDMA, is a popular club and psychoactive drug. Depressants are widely used as prescription medicines to relieve pain, to lower heart rate and respiration, and as anticonvulsants. A stimulant is a psychoactive drug that operates by blocking the reuptake of dopamine, norepinephrine, and serotonin in the synapses of the CNS. Additional regions of the brain that are impacted include the cerebellum and basal ganglia, which help to control coordination and involuntary muscle movements respectively. Depending on the situation, the effects of psychoactive drugs may be beneficial or harmful. Meth has similar effects on the brain and central nervous system, and individuals who abuse it regularly may suffer from hallucinations, anxiety, and confusion as well. Drugs with lower ratios are more dangerous because the difference between the normal and the lethal dose is small. Concurrent use of cocaine and alcohol is more potent and potentially more toxic than use of either aloneA multiple-dose study 1. More than 14 million struggled with alcohol use, 7.4 million struggled with drugs, and 2.5 million struggled with both drugs and alcohol. Relationship Between Substance Abuse and Panic Attacks, Treatment Options for Co-Occurring Disorders, The Connection Between Anxiety and Addiction. (2018). (Ed.). Injecting or smoking cocaine produces a faster, stronger high than snorting it. Sedation, amnesia, muscle contractions and seizures, aggression and violence, psychotic symptoms resembling schizophrenia, and immobility may also occur. Brand names include Centrax, Dalmane, Doral, Halcion, Librium, ProSom, Restoril, Xanax, and Valium. Individuals may then take more of the drug to feel the desired effects. Learn more about the health risks of excessive alcohol consumption. Where to Find a Dual Diagnosis Treatment Center, 24352 Featherstone Canyon Rd, Lakeside, CA 92040. New Scientist, 2518. Most experts feel that using small amounts of caffeine during pregnancy is safe, but larger amounts of caffeine can be harmful to the fetus (U.S. Food and Drug Administration, 2007). It is so effective that when used repeatedly it can seriously deplete the amount of neurotransmitters available in the brain, producing a catastrophic mental and physical crash resulting in serious, long-lasting depression. This method of drug use provides the highest intensity and quickest onset of the initial rush but is also the most dangerous. At any point during each balloon trial, the participant can stop pumping up the balloon, click on a button, transfer all money from the temporary bank to the permanent bank, and begin with a new balloon. Addiction. As the use of the drug increases, the user may develop a dependence, defined as a need to use a drug or other substance regularly. Common types of hallucinogenic drugs are: LSD Mushrooms Ecstasy Marijuana (in high doses) Mescaline Hallucinogens are dangerous and unpredictable. In small doses, they can cause a person to feel more relaxed and less inhibited. Whether a person uses psychoactive substances as medication, recreational drugs, or as part of their daily routine, there are risks to using them. On the other hand, drugs that are normally associated with addiction, including amphetamines, cocaine, and heroin, do not immediately create addiction in their users. The most commonly used of the depressants is alcohol, a colorless liquid, produced by the fermentation of sugar or starch, that is the intoxicating agent in fermented drinks. What are the potential implications of the research for drug use? Cocaine is an addictive drug obtained from the leaves of the coca plant. Some people might also have altered senses, for example, seeing brighter colors. Ayahuasca) and dissociative drugs (PCP, salvia, DXM, ketamine), per NIDA. Consider the research reported in the research focus on risk and cigarette smoking. Ecstasy is also commonly combined with alcohol or other drugs, or cut with toxic substances, which can have potentially hazardous consequences. Cocaine effects on the central nervous system include: Sleeping problems Seizures Breathing problems Change in heart rate Increased blood pressure Loss of smell Paranoia Hallucinations Movement disorders (Parkinson's disease) Loss in gray matter The seven main types are depressants, psychedelics, stimulants, empathogens, opioids, cannabinoids, and dissociatives. Unit 2 Study Guide (1).pdf - Chapter 6 Define The ECS regulates a variety of cognitive and physiological processes in the body, including: Stress; Pain; Memory; Mood . They affect how a person thinks, feels and behaves. Lots of very ordinary substances are recreational drugs: tea and coffee alter mood and cognition as does chocolate; obviously alcohol and tobacco are recreational drugs that are sold and used legally (with certain restrictions). All rights reserved. Levels of some of the brains chemical messengers, or neurotransmitters, are also impacted by drug abuse, including: Regions of the brain are disrupted by drug abuse, as the National Institute on Drug Abuse (NIDA) reports that the brain stem, limbic system, and cerebral cortex are all affected. Toxic inhalants are also frequently abused as depressants. Marijuana also has several long-term side effects on the brain, which are especially prevalent in individuals who use the drug before the brain is fully developed. How Drugs Affect the Brain: Stimulants & Depressants Effects of stimulants include increased heart and breathing rates, pupil dilation, and increases in blood sugar accompanied by decreases in appetite. Drugs can be categorised by the way in which they affect our bodies: depressants slow down the function of the central nervous system. Because they cause a persons breathing to slow, misusing them can cause hypoxia, when the brain does not get enough oxygen. Nicotine, alcohol, and caffeine are all types of psychoactive substances that people frequently consume. Marijuana also acts as a stimulant, producing giggling, laughing, and mild intoxication. Drugs that are smoked may produce throat and lung cancers and other problems. Medline Plus. Retrieved from http://www.fda.gov/downloads/Drugs/ResourcesForYou/Consumers/BuyingUsingMedicineSafely/UnderstandingOver-the-CounterMedicines/UCM205286.pdf. The powerful psychological dependence of the opioids and the severe effects of withdrawal make it very difficult for morphine and heroin abusers to quit using. Psychoactive drugs create negative effects not so much through their initial use but through the continued use, accompanied by increasing doses, that ultimately may lead to drug abuse. Is CBD Really Non-Psychoactive? [It Depends on Who You Ask] Although the U.S. Food and Drug Administration lists caffeine as a safe food substance, it has at least some characteristics of dependence. Related to barbiturates, benzodiazepines are a family of depressants used to treat anxiety, insomnia, seizures, and muscle spasms. When the user powerfully craves the drug and is driven to seek it out, over and over again, no matter what the physical, social, financial, and legal cost, we say that he or she has developed an addiction to the drug. Psychoactive drugs affect the central nervous system in various ways by influencing the release of neurotransmitters (chemical messengers within the nervous system, such as acetylcholine, serotonin, dopamine, norepinephrine), or mimicking their actions. Withdrawal symptoms can include: depression. Psychoactive drugs belong to a broader category of psychoactive substances that include also alcohol and nicotine. Cocaine and meth, especially, produce an intense high as they rapidly flood the brain with dopamine. Retrieved from http://www.newscientist.com/article.ns?id=mg18725181.700. Bath salts have been reported to have a powerful addictive potential, as well as the ability to induce tolerance (more of the drug is required over time to get an equivalent "high"). Depressants inhibit the CNS, increasing the activation of the GABA neurotransmitter. Such abuse may also increase the risk for the onset of Parkinsons disease, a nerve disorder impacting movement. Another problem is the unintended consequences of combining drugs, which can produce serious side effects. It may be the oldest drug on record, known to the Sumerians before 4000 BC. (2009). Over 2.5 million Americans battled opioid addiction in 2015. The adverse effects of ecstasy abuse and/or overdose include hyperthermia, high blood pressure, panic attacks, faintness, involuntary teeth clenching, impaired vision, nausea, sweating, chills, arrhythmia, heart failure, renal failure, dehydration, loss of consciousness, and seizures. Lung complications and infections of the lining of the heart are additional long-term concerns surrounding perpetuated opioid drug abuse. Drugs interact with the brain and body to alter moods, emotions, and behaviors by changing brain chemistry and a persons perceptions, and by impacting how individuals interact with the world around them. LSD can also cause elevated blood pressure, sleeplessness, and dizziness. Introduction to Psychology by University of Minnesota is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License, except where otherwise noted. Ann Arbor, MI: Institute for Social Research, University of Michigan (conducted for the National Institute on Drug Abuse, National Institute of Health). High doses can cause heart failure or seizures. A psychoactive drug or psychotropic substance is a chemical substance that acts primarily upon the central nervous system where it alters brain function, resulting in temporary changes in . This is because heroin increases blood pressure. Opioid overdose is an all too common consequence of opioid abuse, which can often result in severe respiratory depression that can be fatal. In America, more than 130 people die every day from overdosing on opioids, according to the National Institute on Drug Abuse. In 2014, nearly 22 million Americans battled addiction, NSDUH reports. Depressants: These drugs slow down activity in . Wagner, F. A., & Anthony, J. C. (2002). What are the immediate (short-term) effects of heroin use? Psychoactive drugs are substances that, when taken in or administered into one's system, affect mental processes, e.g. Lejuez, C. W., Aklin, W. M., Bornovalova, M. A., & Moolchan, E. T. (2005). Review What is a psychoactive drug? 1.2 The Evolution of Psychology: History, Approaches, and Questions, 2.1 Psychologists Use the Scientific Method to Guide Their Research, 2.2 Psychologists Use Descriptive, Correlational, and Experimental Research Designs to Understand Behavior, 2.3 You Can Be an Informed Consumer of Psychological Research, 3.1 The Neuron Is the Building Block of the Nervous System, 3.2 Our Brains Control Our Thoughts, Feelings, and Behavior, 3.3 Psychologists Study the Brain Using Many Different Methods, 3.4 Putting It All Together: The Nervous System and the Endocrine System, 4.1 We Experience Our World Through Sensation, 4.5 Accuracy and Inaccuracy in Perception, 5.1 Sleeping and Dreaming Revitalize Us for Action, 5.2 Altering Consciousness With Psychoactive Drugs, 5.3 Altering Consciousness Without Drugs, 6.2 Infancy and Childhood: Exploring and Learning, 6.3 Adolescence: Developing Independence and Identity, 6.4 Early and Middle Adulthood: Building Effective Lives, 6.5 Late Adulthood: Aging, Retiring, and Bereavement, 7.1 Learning by Association: Classical Conditioning, 7.2 Changing Behavior Through Reinforcement and Punishment: Operant Conditioning, 7.4 Using the Principles of Learning to Understand Everyday Behavior, 8.2 How We Remember: Cues to Improving Memory, 8.3 Accuracy and Inaccuracy in Memory and Cognition, 9.2 The Social, Cultural, and Political Aspects of Intelligence, 9.3 Communicating With Others: The Development and Use of Language, 10.3 Positive Emotions: The Power of Happiness, 10.4 Two Fundamental Human Motivations: Eating and Mating, 11.1 Personality and Behavior: Approaches and Measurement, 11.3 Is Personality More Nature or More Nurture? As tolerance increases, so does the risk of drug dependency, addiction, and withdrawal. Other symptoms of taking depressants include: When taking depressants, people can develop drug tolerance rapidly. Learn more about it here, including the possible benefits and, MDMA is an illegal, psychoactive drug that has stimulant and hallucinogenic effects. Ecstasy may also be psychologically addictive, leading to withdrawal symptoms when the drug isnt taken. Reports note intense cravings similar to what methamphetamine users experience. The number of pumps that participants take is used as a measure of their tolerance for risk. (1997). While certain drugs like Marijuana have been used for medical purposes to treat both physical and psychological disorders, such Although the level of physical dependency is small, amphetamines may produce very strong psychological dependence, effectively amounting to addiction. Industry Accreditations, Reviews & Ratings. Alcohol acts as a general depressant in the central nervous system, where its actions are similar to those of general anesthetics. Furthermore, the quality and contents of illegal drugs are generally unknown, and the doses can vary substantially from purchase to purchase. Scientists have always assumed that all opioidswhether produced by the body (endogenously) or taken as a druginteract in the same way with opioid receptors. Today cocaine is taken illegally as recreational drug. What do psychoactive drugs do to the brain? - Heimduo Understanding Addiction: Research Studies, State-Funded Drug and Alcohol Rehab Centers, the risk is increased 4-7 times when use begins before the age of 18, Centers for Disease Control and Prevention, has both stimulant and hallucinogenic properties, salvia activates the kappa opioid receptor, Effects of Substance Abuse on Cholesterol, Effects of Drugs & Alcohol on the Nervous System, Chemical Imbalance & Drug Abuse in the Brain: Dopamine, Serotonin & More, The Permanent Effects of Drugs on the Body (Long-Term Impacts), Effects of Drugs & Alcohol on the Circulatory System, Effects of Drug Use & Alcohol On Your Skin, How Drugs & Alcohol Affect the Digestive System. What are the short-term effects of cocaine use? Psychoactive Drugs and Their Effects | 1st Step Behavioral Health Hallucinogens can alter a persons senses and cause them to see or hear things that are not there. Heroin is considered the fastest-acting opioid, taking effect nearly immediately and making it extremely addictive, the Drug Enforcement Administration (DEA) warns. They often fit into one or more categories, including stimulants, depressants, opiates, and hallucinogens. These substances can affect awareness, thoughts, mood, and behavior. Psychoactive drugs are usually broken down into four categories: depressants, stimulants, opioids, and hallucinogens. Abbey, A., Ross, L. T., McDuffie, D., & McAuslan, P. (1996). Hyperthermia, high blood pressure, panic attacks, faintness, involuntary teeth clenching, blurred vision, nausea, sweating, chills, arrhythmia, heart failure, kidney failure, dehydration, loss of consciousness, and seizures are possible side effects of ecstasy abuse and/or overdose. Drug cravings, dependence, and withdrawal symptoms, coupled with a loss of control over use, are signs of addiction. For these reasons, stimulants are frequently used to help people stay awake and to control weight. MDMA (ecstasy, molly) drug facts. Caffeine acts as a stimulant that can aid alertness. In low doses, they produce mild sedation and relieve anxiety; in high doses, they induce sleep.