Your Brain on Drugs (Legal & Illicit)

Explore nervous system cells, including neurons and glial cells, their signaling, myelination by oligodendrocytes and Schwann cells, neurotransmission at synapses, and astrocyte and microglia roles.

Explore the brain and nervous system by mapping CNS and PNS structures, including sympathetic and parasympathetic divisions, cranial nerves, and regions like the hypothalamus, limbic system, and cortex.

Explore cerebral blood flow and CSF, including nitric oxide–driven capillary dilation during brain activity. Examine how CSF cushions the brain and travels through ventricles to deliver nutrients and drugs.

Explore resting potential maintenance by voltage-gated ion channels and the sodium-potassium pump, and action potentials, including depolarization, refractory periods, and saltatory conduction.

Explore how neurotransmitters, signaling molecules synthesized in neurons, are stored and released via calcium-triggered exocytosis, interact with ionotropic and metabotropic receptors, and terminate by reuptake or catabolism, shaping psychopharmacology.

Examine other chemical transmitters, especially hormones, their intracellular receptors and transcription factors, and how the hypothalamus controls pituitary, oxytocin, vasopressin, and melatonin in the circadian rhythm.

Explore how gut microbiota and probiotics influence mood and mental health, including research on germ-free mice, major depressive disorder, and anxiety.

Pharmacodynamics explains drug mechanisms of action at synapses, including tetrodotoxin blocking sodium channels, and tetrabenazine, haloperidol (D2 receptor antagonism), moclobemide, and cocaine.

Define binding affinity and receptor efficacy, and compare agonists, antagonists, and partial agonists in metabotropic and ionotropic receptors. Explain allosteric regulators and positive or negative modulators, including gabaa and benzodiazepines.

Examine how chronic drug use shifts dose-effect curves and alters pharmacokinetics and pharmacodynamics, driving sensitization, tolerance, receptor changes, behavioral and contingent (pavlovian) tolerance, and withdrawal.

Explore neurotoxicity and environmental neurotoxicology, detailing neurotoxins, endocrine disruptors like Bisphenol A, PCBs, and exposure routes from plastics, pesticides, and building materials, plus related neural diseases.

Compare regulatory agencies and drug classification across the United States and the United Kingdom, detailing schedules and abuse potential under the Harrison Narcotics Act and the Controlled Substances Act.

Explore how the DSM defines addiction as a substance use disorder, with cravings, tolerance, withdrawal, and continued use despite problems, plus early and sustained remission and maintenance therapy.

Explore major theories of drug addiction, including associative learning, reinforcement, and conditioned stimuli, and compare drive, opponent process, allostasis, incentive salience, disease models, and implications for goal-directed behavior and craving.

Trace the brain’s reward circuitry, showing mesolimbic dopamine from the ventral tegmental area to the nucleus accumbens and its reinforcing effects.

Explore how chronic drug use reshapes learning and memory through reward circuitry, delta-fosb–driven dendritic changes in GABA neurons, amygdala–prefrontal cortex interactions, and hippocampal context.

Explore the stages of drug addiction from intoxication to withdrawal, preoccupation, and relapse, and examine the neurobiological roles of the amygdala, triggers, and mortality.

Detoxification combines medication and relapse prevention, then uses drug replacement therapies like buprenorphine or methadone, alongside psychotherapy, cognitive behavioral therapy, and 12-step programs to reduce cravings.

Explore how food addiction relates to obesity and bulimia nervosa within substance use disorder criteria, and review nucleus accumbens dopamine reward and cognitive behavioral approaches and 12-step groups.

Examine psychostimulants, also called sympathomimetics, that boost alertness and mood, and explore substances like amphetamine, methylphenidate, cathinones, cocaine, ephedra, and modafinil, along with medical uses and abuse patterns.

Learn how amphetamine, cocaine, and methamphetamine increase dopamine in the nucleus accumbens through vesicle displacement, transporter reversal, and altered reuptake, with cart peptides modulating these effects.

Examine how psychostimulants activate the sympathetic nervous system, increasing heart rate, constricting blood vessels, dilating pupils, reducing saliva and digestion, and shaping appetite, mood, and goal-directed behavior.

Explore the medical uses of psychostimulants, including ADHD treatment and cognitive enhancement, and review prevalence among students and how wakefulness and dopamine in limbic system and prefrontal cortex affect learning.

Explore nicotine's role in tobacco and health risks across cigarettes, cigars, pipes, hookah, smokeless forms, and e-cigarettes. Explain exposure, second hand smoke, third hand smoke, and cessation approaches.

Trace the history of tobacco from ancient religious use to modern regulation, and explain nicotine pharmacokinetics, absorption routes, pH effects, cotinine metabolism, and genetic influences.

Nicotine acts as a cholinergic nicotinic receptor agonist across peripheral, autonomic, and central systems. It causes desensitization and upregulation, elevating dopamine in the nucleus accumbens via the ventral tegmental area.

Explore nicotine's effects on heart rate, blood pressure, appetite, memory, and attention, and how acute and chronic tolerance shape positive and negative subjective experiences across smokers, non-smokers, and e-cigarette users.

Compare nicotine user types like tippers, chippers, and zippers, while noting Alpha5, Alpha3, and beta4 receptor subunit gene expression on chromosome 15, and explore quitting via nicotine replacement, varenicline, and bupropion.

Explore caffeine, a psycho stimulant from the xanthine class, its sources: coffee, tea, kola, cacao, and energy drinks, and the varying caffeine content and health risks.

Track caffeine pharmacokinetics from ingestion to absorption and peak blood levels around 40 minutes. Learn metabolism by CYP1A2 and CYP2E1, formation of paraxanthine, and adenosine receptor antagonism that promotes alertness.

Explore caffeine's uses and mild psychostimulant effects, its abuse potential, withdrawal and tolerance, energy drink risks, and debates on caffeine as a substance use disorder.

Examine how depressants modulate brain activity by enhancing GABA neurotransmission at GABAa receptors and allosteric sites, linking mood-elevating effects to alcohol, barbiturates, benzodiazepines, opioids, and cannabinoids.

Examine barbiturates from ultra short to long acting, their anesthetic and abuse risks, and gamma hydroxybutyrate as a club drug, narcolepsy treatment, and safety concerns.

Explore how benzodiazepines act as depressants, their history with Librium and Valium, metabolism by cytochrome P450 enzymes, withdrawal and dependence risks, craving, and related safety concerns.

Explore z-drugs as non-benzodiazepine hypnotics that bind benzodiazepine sites on gabaa receptors, highlighting sleep related behaviors, impairment risks, and the need for about eight hours of sleep.

Define ethyl alcohol as a central nervous system depressant and distinguish it from methanol; explain fermentation and distillation that produce beer, wine, spirits, and other alcohol forms, plus standard drink.

Explore the pharmacokinetics of alcohol, including absorption in the upper intestine and stomach, metabolism by alcohol dehydrogenase and CYP2E1, and acetaldehyde effects. Discuss zero-order kinetics, acetaldehyde buildup, and drug interactions.

Explore how alcohol modulates the central nervous system by activating GABA A receptors and inhibiting NMDA receptors, influencing dopamine in the nucleus accumbens via the ventral tegmental area.

Explore alcohol's physiological and behavioral effects, from acute cardiovascular and respiratory changes to memory impairment, judgment, and risk of binge-related harm, plus long-term organ risks and treatment options.

Explore what a hangover is and its symptoms like headaches and fatigue. See how acetyl aldehyde buildup and other alcohol effects contribute and how hangovers affect absenteeism and productivity.

Explore how opioids interact with mu and other receptors to produce pain relief, reward, and addiction, including prescription and synthetic varieties, misuse, and treatment options.