Drugs & Consciousness

CNS stimulants - Cocaine

- Cocaine induces immediate euphoria followed by a crash - Blocks reuptake of the NT Dopamine (and Serotonin) Therefore a Dopamine is an ​agonist - Various forms can be smoked, sniffed or injected.

Other Drugs that Effect Dopamine

- DA Receptor Blockers - antagonists (ANT) Treats schizophrenia - L-DOPA (increases production of Dopamine in the presynaptic neuron) - agonist (AGO) Treats Parkinson's disease - Opiates - Stimulante DA and Endorphin Receptors - agonist (AGO)

Transmitter substances are

- Synthesized, stored, released, bound, and terminated during neural transmission - These processes are susceptible to drug manipulations

Paradoxical Effects of Anxiolytics

-Anti-anxiety agents impair motor skills, judgment, and memory... but reduces self-awareness of the impairment. -Paradox = Though people are objectively clearly impaired, they subjectively believe that they are not

Olds and Milner Study

-Establishing neural pathways for reward -Electrical stimulation of "pleasure centers" of the brain (hypothalamus and nucleus accumbens) -Compare Olds and Milner to self-administration of cocaine studies in rats

Depressants

1. Alcohol affects motor skills, judgment, and memory... and increases aggressiveness while reducing self awareness. 2. Barbiturates: Drugs that depress the activity of the central nervous system, reducing anxiety but impairing memory and judgment. Nembutal, Seconal. and Amytal are some examples. 3. Opiates: Opium and its derivates (morphine and heroin) depress neural activity, temporarily lessening pain and anxiety. They are highly addictive

Anti-anxiety drugs (anxiolytics)

1. Benzodiazepines - Valium - Librium - Xanax - Clonazepam 2. GABA receptor agonists

Example of stimulants are:

1. Caffeine 2. Nicotine 3. Cocaine 4. Ecstasy 5. Amphetamines 6. Methamphetamines

Psychoactive drugs are divided into several groups:

1. Stimulants 2. Depressants 3. Hallucinogens 4. Anxiolytics

opium and its derivatives, including heroin, morphine, and codeine, were legal in the United States until ______ and used in a variety of over the counter medications

1914

What is the most frequently ingested psychoactive substance worldwide?

Caffeine

Addiction and the Brain

Continued drug use sharply reduces the number of dopamine receptors in the brain's reward system.

Dependence & Addiction

Continued use of a psychoactive drug produces tolerance. With repeated exposure to a drug, the drug's effect lessens. Thus it takes greater quantities to get the desired effect.

Hallucinogenic/Stimulant - Ecstasy

Ecstasy or Methylenedioxymethamphetamine (MDMA) is a stimulant and mild hallucinogen. It produces a euphoric high and can damage serotonin-producing neurons, which results in a permanent deflation of mood and impairment of memory.

What are psychedelic (mind-manifesting) drugs that distort perceptions and evoke sensory images in the absence of sensory input?

Hallucinogens

Runner's "high" is associated with:

Increased release of endorphins

What powerful hallucinogenic drug is also known as acid?

LSD (lysergic acid diethylamide)

Why do people smoke?

Nicotine itself is rewarding (positive reinforcement) Nicotine takes away unpleasant cravings (negative reinforcement) by triggering epinephrine, norepinephrine, dopamine, and endorphins

Paradoxical Effects of Nicotine

Nicotine makes a person feel both more alert and more relaxed at the same time However this is not a linear relationship - Nicotine is a CNS stimulant - Nicotine is PNS relaxant

Why Do People Smoke?

People smoke because it is socially rewarding Smoking is also a result of genetic factors

What can affect consciousness by disrupting neural transmission in a variety of ways (i.e, mechanism of action)?

Psychoactive drugs

Tolerance and Sensitization

Repeated administration of a drug can alter its subsequent effectiveness -Tolerance: Repeated drug administration results in diminished drug effect (or requires increased dosage to maintain constant effect) --Withdrawal effects are often the opposite of the drug effect and often accompanies tolerance --Tolerance can reflect decreased drug-receptor binding or reduced postsynaptic action of the drug -Sensitization: Repeated drug administration results in heightened drug effectiveness (e.g DA receptor blockers used to treat schizophrenia)

What are drugs that excite neural activity and speed up body functions?

Stimulants

Drugs

Summary

How a drug affect these processes is called:

The mechanism of action

Marijuana use

The use of marijuana in teenagers is directly related to the "perceived risk" involved with the drug

Which of the following is not true of SSRI's?

They function via enzymatic deactivation

psychoactive drugs

a chemical substance that alters perceptions and moods (affects consciousness)

Opiates

depress neural activity, relieve pain, produce feelings of euphoria

Antagonists

drugs that block or inhibit the postsynaptic effects of the NT

Agonists

drugs that facilitate the postsynaptic effects of the NT

T/F The world's most widely consumed psychoactive drug is nicotine.

false

T/F Those given morphine to control pain often become addicted to the drug

false

T/F In large amounts, alcohol is a depressant; in small amounts, it is a stimulant.

false

Example of opiates

opium, morphine, heroin, methadone, and Prescription Painkillers

When repeatedly flooded with artificial opiates, the brain eventually stops producing its own painkilling neurotransmitters, the endorphins, leading to higher use of the artificial opiates and eventually, if not stopped, possible death by __________.

overdose

THC (delta-9-tetrahydrocannabinol)

the major active ingredient in marijuana (hemp plant) that triggers a variety of effects, including mild hallucinations

T/F People who use cocaine are often able to discontinue their drug use without professional help.

true

T/F: Adopted individuals are more susceptible to alcohol dependence if one or both biological parents have a history of it.

true