Exam 3 Nicotine and Caffeine
How addictive is nicotine?
about 2/3 (67%) become addicted
why are people addicted to nicotine
acetylcholine is tightly linked to reward and dopamine (positive reward model). easy to get animals to self-administer. also physical dependence model with withdrawal
caffeine on the brain
blocks activity of adenosine receptors. in higher doses blocks GABA, stimulates depolarization, increase action potentials with calcium
"wide awake" drunk
caffeine counteracts the effects of alcohol, you feel sober but you are impaired and can do risky behaviors like driving
Medicinal value of nicotine
could help headaches and weight loss historically, but not much value since 1890s
health benefits of caffeine
daily coffee decreases likelihood of liver cancer rectal cancer, Parkinson's disease, Alzheimer's Disease (small effect)
caffeine withdrawal
fatigue, headache (still prevalent with placebo)
John Oliver: big companies and cigarettes
governments started to regulate in Western countries so they moved to unregulated places such as India
how lethal is nicotine
highly toxic and relatively low lethal dose. high absorption rate
nicotine and cognition
improves attention and response time
health risks of caffeine
increase cholesterol, osteoporosis, gastrointestinal problems, maybe gestational
health and neural effects of nicotine addiction
increased risk of many health problems. permanent neural changes in prefrontal cortex, more nicotinic receptors
treatments for nicotine abuse and effectiveness
largely involve nicotine in controlled amounts, behavioral interventions largely ineffective. Chantix (nicotinic receptors and cholinergic system) and Zyban (dopamine)
effects of caffeine on the body
low dose creates stimulant effect but too much is counter-intuitive and activity decreases. also diuretic, increase HR and BP. impairs ability to make decisions
too much caffeine - intoxication
more than 1000mg per day. looks like anxiety disorder, cardiac arrhythmias
what makes cigarettes toxic
nicotine is very toxic plus tar, carbon monoxide, ammonia, acetone and other
how does nicotine act in the brain
nicotinic receptors activate acetylcholine in ventral tegmental area, cause release of dopamine. crosses blood brain barrier in 7 seconds.
how common is caffeine use
very common, 80-90% of US population but difficult to assess because multiple products
How common is smoking (age, sex, education)
very common, mostly men. women smoke less but feel effects more. higher education means less likely to smoke
adenosine
when it hits the receptor it makes you drowsy. low doses of coffee act as stimulant, high makes you drowsy
Historical smoking trend
1900 not very prevalent, huge increase after WWI. 1950s smoking linked to lung cancer then filtered cigarettes and advertising. still used a lot but becoming less prevalent over time
