3: Drugs and Consciousness
Substance Use Disorders and Diagnostic Considerations
In current psychiatric diagnostic systems, there are separate categories for substance- and medication-induced disorders.
A substance or a medication-induced disorder occurs when people misuse drugs and alcohol causing changes that resemble various psychological disorders, including dysfunctions such as sexual dysfunctions, obsessive-compulsive disorder, depression, psychosis, and sleep and neurocognitive disorders.
A psychoactive drug is any chemical substance that alters the brain, causing changes in perceptions and moods.
A substance use disorder is a disorder characterized by continued substance use despite significant disruption in life.
When is drug use a disorder?
According to the American Psychiatric Association, a person may be diagnosed with a substance use disorder when the drug use continues despite significant life disruptions.
Brain changes can persist even after quitting use, and these changes can lead to strong cravings when exposed to cues or situations associated with drug use.
Severity of Substance Use Disorder:
Mild: 2-3 indicators
Moderate: 4-5 indicators
Severe: 6+ indicators
If concerned about own or a loved one’s substance use, resources include York University student supports, a medical/family doctor, or a health clinic.
Thinking critically about tolerance and addiction is covered in LOQ 10.2.
Key questions: What roles do tolerance and addiction play in substance use disorders, and how has the concept of addiction evolved?
Tolerance: repeated use leads to the need for larger doses to achieve the same effect.
Example: over-the-counter pain relievers (e.g., starting with regular Tylenol, escalating to extra-strength, caplets, etc.) to achieve the same relief.
Addiction: compulsive craving for a drug or certain behaviors (e.g., gambling) despite harmful consequences.
Withdrawal: discomfort or distress following discontinuation of the addictive drug or behavior.
LOQ 10.2 and Thinking critically about tolerance and addiction provide deeper context.
Depressants
Examples include alcohol, barbiturates (tranquilizers), and opiates.
General effect: depress neural activity and slow body functions.
Alcohol
Acts as a disinhibitor: slows neural processing and acts as a potent sedative, especially with sleep deprivation.
Disrupts memory and long-term brain development; long-term use impairs growth of synaptic connections.
Effects: reduces self-awareness and self-control; narrows focus to arousing situations and away from future consequences.
Alcohol use disorders are associated with more than other diseases.
Brain changes include shrinkage and reduced gray matter; gender differences exist in risk.
Neuroanatomical changes can be observed on MRI scans (e.g., brain shrinkage in alcohol use disorder).
Tolerance and withdrawal drive continued problematic use.
Barbiturates
CNS depressants that reduce anxiety but impair memory and judgment.
Potentially lethal when combined with alcohol or other depressants.
Brand names include Nembutal, Seconal, and Amytal (as stated: Nembitol, Seconal, and Ametol in the transcript).
Opiates (opioids)
Includes opium and derivatives (e.g., codeine, morphine, heroin).
Extremely addictive; first time in US history, accidental opioid overdose deaths surpassed motor-vehicle deaths (reported in 2019).
COVID-19 pandemic increased stress and uncertainty, potentially contributing to more opioid-related deaths.
Signs: constricted pupils, slowed breathing, lethargy.
Withdrawal occurs if ingestion stops.
Common opioid medications: Oxycodone, Vicodin, Fentanyl, Methadone.
The opioid crisis involved aggressive marketing by pharmaceutical companies and over-prescription, contributing to widespread addiction; fines have been levied for marketing practices.
Social influences: being around others who use opioids increases risk of use.
Stimulants
Stimulants excite neural activity and accelerate body functions.
Physiological effects: dilated pupils, increased heart rate and breathing, higher blood sugar, reduced appetite; prepares body for fight-or-flight.
Effects include increased energy and self-confidence; can be addictive.
Common stimulants:
Nicotine and caffeine (simple stimulants, widely available)
Amphetamines, cocaine, MDMA (ecstasy), methamphetamine
Nicotine (in tobacco)
Highly stimulating and addictive; signals CNS to release neurotransmitters, diminishes appetite, boosts alertness and fatigue resistance.
Withdrawal includes acute cravings and other symptoms that make quitting difficult.
Vaping/e-cigarettes: rapid rise in use; by 2019, US high school students used e-cigarettes at five times the rate of traditional cigarettes.
Nicotine pharmacokinetics: reaches brain within about seven seconds, faster than intravenous heroin; rapid systemic distribution.
Health statistics: smoking is a leading cause of preventable death in the US (≈ deaths/year in the US; about half a million).
Historical and cultural trends: US smoking rate declined from 45% in 1955 to 15% in 2019; worldwide rate down ~30% since 1990.
Cessation: about three in four smokers wish to quit; fewer than one in seven succeed; nicotine replacement and counseling/peer support improve success.
Cocaine
Effects depend on dose, form, and user expectations; can be snorted, injected, or smoked.
Strongly activates brain reward pathways; rapid onset of euphoria followed by a crash (agitation/depression) as drugs wear off.
Mechanism: blocks reuptake of dopamine, norepinephrine, and serotonin, increasing their levels in the synapse.
Alcohol or nicotine use often precedes cocaine use and can amplify the brain’s response to cocaine.
Other stimulants (brief mentions)
Methamphetamine and Ecstasy (MDMA) also have significant neurological impact and withdrawal experiences.
Hallucinogens
Hallucinogens distort perceptions and evoke sensory images without external input.
LSD (acid) is a powerful hallucinogen; mood and expectations color the experience, which can range from euphoria to detachment to panic.
Mechanism: interacts with serotonin neurotransmitter systems; perceptual distortions and altered mood are common.
Typical perceptual effects include intensified colors and visual distortions; some users report bright central light and tunnel-like visual fields.
Marijuana (Cannabis)
Active compound: THC (tetrahydrocannabinol) in leaves.
Effects: amplifies sensitivity to colors, sounds, tastes, and smells; acts as a depressant and disinhibitor with a euphoric high.
Medical uses: can aid sleep, mood improvement; can alleviate chronic pain, chemotherapy-induced nausea, and muscle soreness in MS.
Risks: frequent use, especially during adolescence, linked to increased risk of anxiety, depression, psychosis, and suicidal behavior.
Marijuana may act as a gateway drug for future alcohol and opioid use in some individuals.
Table 10.2: Guide to Psychiatric Psychoactive Drugs
The module highlights a reference table (Table 10.2) that categorizes psychoactive drugs and their psychiatric effects.
Influences on Drug Use and Patterns of Use
Why do some people become regular users of consciousness-altering drugs?
Biological vulnerabilities: genetics, brain differences (e.g., twin/adoption studies).
Psychological factors and sociocultural influences create different pathways for misuse and for treatment/prevention.
Warning signs of alcohol use disorder (AUD):
Binge drinking definitions: Five drinks or four drinks over two hours.
Craving or strong desire to drink.
Failure to meet work/school/home responsibilities due to drinking.
Noncompliance with resolutions to drink less.
Continued use despite health risks (e.g., liver damage).
Avoiding social activities or drinking alone.
Psychosocial-Cultural Influences on Disordered Drug Use
Biological and genetic factors: predispositions and neurotransmitter system variations contribute to risk.
Psychological factors: significant stress, depression, and existing psychological disorders interact with drug use.
Social and cultural factors:
Cultural acceptance of drug use
Negative peer influences or supportive peer norms against use
Environment and trauma histories
Perceived risk of drug use, family and religious norms
Peer influence is particularly powerful (as illustrated by Figure 10.6):
Example: Among 11-17 year olds, the percentage who smoked a cigarette in the last 30 days correlates with whether their friends smoked; “kids don’t smoke if their friends don’t smoke.”
Prevention programs focus on:
Education about long-term costs and health risks
Building self-esteem and sense of purpose
Providing refusal skills and alternative activities
Moving beyond simplistic “Just say no” messages to more comprehensive prevention strategies
Summary and Practical Implications
Substance use disorders involve persistent brain changes and cravings even after cessation, with varying severity levels.
Tolerance, addiction, and withdrawal are core concepts in understanding substance use disorders.
A wide range of psychoactive drugs affect the brain differently (depressants, stimulants, hallucinogens, and cannabis), with distinct physiological and psychological consequences.
Socio-cultural and biological factors interact to shape risk, progression, and response to treatment.
Prevention and treatment emphasize education, self-efficacy, social support, and individualized approaches that consider genetics, environment, and mental health.
References to Critical Resources in the Transcript
LOQ 10.2: Thinking critically about tolerance and addiction.
Table 10.2: Guide to psychiatric psychoactive drugs.
Figure 10.6: Percentage of 11-17 year olds who smoked a cigarette in the last 30 days, illustrating peer influence.
Final Note
Module 10 closes with a transition to Chapter 4 and Modules 11–13, encouraging breaks and a shift to new content.