Drugs and the Brain

1
Drugs and the Brain

• Psychoactive Drugs and Behavior
• Tolerance and Sensitization
• Psychoactive Drugs
• Stimulants
• Hallucinogens
• Depressants

2
Neurotransmitter Pathway
3
Drugs and States of Consciousness

• Psychoactive Drugs
• Are any mind altering chemicals
• They change how you perceive and feel
• There are both legal and illegal psychoactive
  drugs
• The psychological effects of psychoactive drugs
  depend on dosage, form taken, expectations,
  personality of user situation

4
Tolerance

• Tolerance is a decrease in the effect
• Many opiates will loose their effectiveness
  within two weeks if dosing is not increased to
  match the development of tolerance

5
Sensitization

• Sensitization is an increase in the effect
• thought to be central to the development of
  craving

6
Physical Dependence

• Physical dependence is characterized by an
  inability to stop taking a drug without
  experiencing a withdrawal syndrome
• The symptoms of withdrawal vary depending on the
  effects of the drug

7
Addiction
Addiction

• Development of addiction
• Tolerance
• Sensitization
• Physical dependence
• Drug seeking behavior
• Misconceptions about addiction
• Addictive drugs quickly corrupt
• Addictions cant be overcome voluntarily
• We can extend the concept of addiction to cover a
  whole spectrum of repetitive, pleasure-seeking
  behaviors

8
Stimulants

• Often used to stay awake, lose weight, boost mood
  or athletic performance
• Benefits come with a price
• Crash (fatigue, headaches, irritability,
  depression)
• stimulants are addictive
• Most common stimulants are
• caffeine
• nicotine
• amphetamines (speed), ephedrine
• cocaine

9
Stimulants Caffeine

• Most widely consumed drug in world
• Found in many foods, drinks, meds
• coffee, tea, sodas, cocoa, chocolate, Vivarin,
  Anacin, Excedrin, No Doz, Midol, cold meds
• Rapidly absorbed following ingestion
• Reaches peak blood levels-30 min

10
Stimulants Nicotine

• 1 of top 3 psychoactive drugs used in Western
  society (caffeine alcohol)
• Consumed in various forms
• Responsible for many preventable health problems
• Responsible for approx. 1100 premature deaths in
  America per day (40,000 per year)

11
Stimulants Amphetamine, Cocaine and Ephedrine
(Ma-huang)

• These stimulants are powerful psychostimulants
  that affects ones mental functioning and
  behavior and are widely recognized drugs of abuse
• Amphetamine, cocaine and ephedrine all cause an
  increase norepinephrine, dopamine and/or
  serotonin in the synaptic gap

12
Hallucinogens

• Psychedelic drugs that distort perceptions and
  evoke sensory images in the absence of sensory
  input
• LSD
• Marijuana
• Ecstasy
• Bufotenin (toad licking)
• Mescaline (peyote)
• PCP (angel dust)
• Ketamine (Special K)
• Ololuiqui (morning glory seeds)
• These and many others often derived from plant
  and animal products and historically used for
  religion or magic.

13
Hallucinogens THC (marijuana)

• changes brain chemistry
• long term use may
• depress male sex hormone and sperm levels
• damage more than cigarette smoking
• hasten loss of brain cells
• cognitive effects outlast period of smoking
• THC and byproducts stay in body for month or more
• contrary to tolerance, w/ regular use, may result
  in sensitization (need less to get same initial
  high)
• can be therapeutic

14
Depressants

• Central Nervous System Depressants-reduce neural
  activity and slow body functions (alcohol,
  barbiturates, opiates)
• at moderate doses produce decrease in
• environmental awareness
• responses to sensory stimulation
• cognitive functioning
• spontaneity
• activity
• pain