Transcript Document
Wake Up and Smell the Caffeine Psychology 2800 7/18/2015 Caffeine 1 Introduction 7/18/2015 The most popular psychoactive drug in North America How many people here DO NOT ingest caffeine? Caffeine 2 7/18/2015 Caffeine 3 Introduction 7/18/2015 That includes: Coffee 130 mg Tea 40 mg Soft Drinks (colas) 30 – 90 mg Cold and Headache medications 15 – 50 mg Rev ?, probably about 100 mg Chocolate! 50 – 100 mg Wake up pills 100 – 500 mg Caffeine 4 Introduction 7/18/2015 Almost always taken orally, absorbed in small intestine. Crosses all barriers Absorbed more slowly from cold beverages Less than 2% is excreted Caffeine 5 Metabolism Half life is between 30 min and 3.5 hr Metabolism slowed by birth control pills Sped up by broccoli! 2x faster in smokers 7/18/2015 Caffeine 6 Metabolism That was with adults (well not kids anyway) Different deal in kids and infants 85% excreted 4 DAY half life Different pathways and metabolism than in adults More similar to non-humans 7/18/2015 Caffeine 7 Neurophysiological Effects. Like alcohol, we don’t know! Might block adenosine Neuromodulator that inhibits firing So, caffeine disinhibits? High doeses block benzodiazipine receptors 7/18/2015 Caffeine 8 Neurophysiological Effects Might cause release of epinephrine Causes smooth muscles to relax, striate muscles to contract Decreases airway resistance 7/18/2015 Good for asthma, colds Constriction of blood vessels to the brain Dilation other places Caffeine 9 Neuropshysiological Effects Not sure if it helps performance Increases FA levels, could be performance enhancing, especially for long athletic events. Does reduce drowsiness,boredom. Controlled substance. Increases time in light sleep Stages 1 and 2 Can counteract barbiturates. 7/18/2015 Caffeine 10 Effects on Nonhumans Small doses increase SMA Large doses do the opposite Increases FR responding 7/18/2015 Affects timing Increases suppressed behaviour. Generalizes to coke, not to amphetamine. Caffeine 11 But, how does that first cup make you feel? Humans are great at discriminating Caffeine makes us: Energized Focused Motivated Same in non users All at low-moderate doses (20-200 mg) 7/18/2015 1.8 mg, about a sip of coffee!! About a cup of coffee. Caffeine 12 Could I ever use a coffee Tolerance Withdrawal 7/18/2015 Sustained use leads to more adenosine receptors Whole deal changes if big dose given to non users. Headache Flu like symptoms Bad attitude in general 100 mg a day, most all of us! Caffeine 13 Reinforcing Properties Hard to get animals to selfadminister Will prime cocaine use Lots of variation in us Task demands Caffeine experience. Demand is relatively inelastic. 7/18/2015 Late 1970s, 6 bucks a pound. Caffeine 14 Bad Stuff Cancer? Caffeinism OD? 30-80 cups of coffee Reproduction Chromosomal damage? Toxicity Cardiac effects? 7/18/2015 Depends on method Caffeine 15 Beware the International Coffee Conspiracy! 7/18/2015 Caffeine 16