The Brain, The Brain, Nervous System, & Nervous System, & NeurotransmissionNeurotransmission

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How drugs influence the How drugs influence the brain, body & behavior.brain, body & behavior.

What is a Drug?What is a Drug?

►What does the substance do to the body?What does the substance do to the body? Psychoactive, physiological, Psychoactive, physiological, Impairment: Physical, psychological, socialImpairment: Physical, psychological, social

►What is the intent of the use?What is the intent of the use? Instrumental, RecreationalInstrumental, Recreational

►Social ConstructionismSocial Constructionism Good-Bad, Legal-Illegal, Accepted-RejectedGood-Bad, Legal-Illegal, Accepted-Rejected

Where do Drugs come Where do Drugs come From?From?

►Origins of Drugs are Organic / NaturalOrigins of Drugs are Organic / Natural

►Processing increases concentration.Processing increases concentration. Pharmaceuticals are an example.Pharmaceuticals are an example.

►Designer DrugsDesigner Drugs Non-naturally occurring substances. Non-naturally occurring substances.

Target specific functions.Target specific functions.

Drug Delivery MethodsDrug Delivery Methods► InhalingInhaling

Fastest Route to BrainFastest Route to Brain► InjectingInjecting

Mainlining & Skin Mainlining & Skin PoppingPopping

Intra-muscularIntra-muscular► AbsorptionAbsorption

Nasal, Oral, Skin PatchesNasal, Oral, Skin Patches► IngestionIngestion

Eating & DrinkingEating & Drinking Slowest & Largest Slowest & Largest

QuantityQuantity

InhalationInhalation► VERY FAST - body needs VERY FAST - body needs

OO22

► 5-8 seconds from lungs 5-8 seconds from lungs to brainto brain

► Burn, breathe in particlesBurn, breathe in particles► BUT other particles tooBUT other particles too► Emphysema, asthma, Emphysema, asthma,

lung cancerlung cancer► Exs: nicotine, crack, Exs: nicotine, crack,

THC(MJ), anesthetics, THC(MJ), anesthetics, gasoline, gluesgasoline, glues

InjectingInjecting ► Bypasses digestive system - more Bypasses digestive system - more direct route to blooddirect route to blood

► Intravenous (IV)Intravenous (IV) - fastest 15 sec - fastest 15 sec to brain (heroin) Rapid, intense, to brain (heroin) Rapid, intense, irreversibleirreversible

► Intramuscular (IM)Intramuscular (IM) -arm, butt. -arm, butt. Slower absorption. Slower absorption.

► Ex: measles, tetanus, flu shotsEx: measles, tetanus, flu shots► Sub-cutaneous (Sub-Q)Sub-cutaneous (Sub-Q) - needle - needle

into tissue under skin. Slower, skin into tissue under skin. Slower, skin gets irritated. Skin poppinggets irritated. Skin popping

► Disadvantage:: bacteria, virus Disadvantage:: bacteria, virus spreadspread

AbsorptionAbsorption

► NasalNasal - snuff, cocaine. - snuff, cocaine. Adheres to mucous Adheres to mucous membrane in nose, membrane in nose, dissolved into blooddissolved into blood

► OralOral - chewing tobacco - chewing tobacco► Rectum Rectum - rectal - rectal

suppositorysuppository► SkinSkin - patches. Nicotine, - patches. Nicotine,

estrogen, motion-sicknessestrogen, motion-sickness

IngestionIngestion

►Eating and drinkingEating and drinking►Oldest methodOldest method►Slowest method - takes 5-Slowest method - takes 5-

30 min to be absorbed30 min to be absorbed►6-8 hour grace period6-8 hour grace period►Acids absorbed better Acids absorbed better

than basesthan bases►Many barriers so need Many barriers so need

larger quantitieslarger quantities

Factors Influencing Factors Influencing EffectsEffects

► Quantity & Quantity & ConcentrationConcentration

► Size of IndividualSize of Individual► GenderGender► EthnicityEthnicity► Expectation EffectsExpectation Effects

► Drug CombinationsDrug Combinations Additive Additive

► (3 + 4 = 7)(3 + 4 = 7)

Potentiation Potentiation ► (0 + 5 = 7)(0 + 5 = 7)

Synergism Synergism ► (5 + 5 = 15)(5 + 5 = 15)

Antagonistic Antagonistic ► (5 + 7 = 3)(5 + 7 = 3)

Toxic ReactionsToxic Reactions

Dose Response CurvesDose Response Curves

►Effective Dose: Effective Dose: ED-1, ED-50, ED-99ED-1, ED-50, ED-99

►Lethal Dose: Lethal Dose: LD-1, LD-50, LD-99LD-1, LD-50, LD-99

►Margin of Safety: Margin of Safety: LD-1 / ED-99LD-1 / ED-99

►Therapeutic Index: LD-50 / ED-50Therapeutic Index: LD-50 / ED-50

Organization of Nervous Organization of Nervous SystemSystem

Parasympathetic - Parasympathetic - SympatheticSympathetic

Drug Action Through the Drug Action Through the BrainBrain

►Of all the Chemical Compounds, Only Of all the Chemical Compounds, Only about 30 are abused by Humansabout 30 are abused by Humans

►Drugs Achieve Effects Through BrainDrugs Achieve Effects Through Brain►Drugs Reach the Brain through the Drugs Reach the Brain through the

Blood SupplyBlood Supply►All Drugs of Abuse Cross the Blood All Drugs of Abuse Cross the Blood

Brain BarrierBrain Barrier

Brain AnatomyBrain Anatomy

Brain: Regionalized Brain: Regionalized FunctionsFunctions

Brain Stem AnatomyBrain Stem Anatomy

Major Functions of Brain Major Functions of Brain StemStem

►Regulation of Homeostasis of Body Regulation of Homeostasis of Body FunctionsFunctions

►Refined Motor Control & PostureRefined Motor Control & Posture►Signal ProcessingSignal Processing►Memory FormationMemory Formation►Drive StatesDrive States►Basic Emotions (Appetitive & Basic Emotions (Appetitive &

Defensive)Defensive)

Brain Stem Structures & Brain Stem Structures & FunctionsFunctions

►MedullaMedulla Blood PressureBlood Pressure BreathingBreathing Heart RateHeart Rate Body TemperatureBody Temperature DigestionDigestion

►Vomit Vomit Reflex/ResponseReflex/Response

►PonsPons Sleep PatternsSleep Patterns General AlertnessGeneral Alertness

Brain Stem Structures & Brain Stem Structures & FunctionsFunctions

HypothalamusHypothalamus• Survival Drives Survival Drives

(Appetitive)(Appetitive)

EatingEating

DrinkingDrinking

Sexual Sexual BehaviorBehavior

Limbic SystemLimbic System• Organization of Organization of

Defensive Defensive Emotional Emotional BehaviorBehavior

• Mood StatesMood States

Brain Stem Structures & Brain Stem Structures & FunctionsFunctions

Substantia nigraSubstantia nigra► Motor ControlMotor Control► Tonic Body PostureTonic Body Posture

CerebellumCerebellum► Refined Refined

CoordinationCoordination

ThalamusThalamus► Signal Processing Signal Processing

Coordination of Coordination of Sensory Input - Sensory Input - RelayRelay

HippocampusHippocampus► Memory FormationMemory Formation

LearningLearning

Organization of Cerebral Organization of Cerebral RegionsRegions

Cerebral Cortex Cerebral Cortex

Temporal LobeTemporal Lobe

► New Learning New Learning (Hippocampus)(Hippocampus)

► Short-Term Short-Term MemoryMemory

► Long-Term Long-Term MemoryMemory

Frontal LobeFrontal Lobe

► AttentionAttention► ConcentrationConcentration► Problem Problem

SolvingSolving► JudgmentJudgment► EmotionalityEmotionality

Parietal LobeParietal Lobe

► Integration of Integration of Sensory Sensory InformationInformation

► Somatic Somatic HallucinationHallucinationss

► Reality Reality DistortionDistortion

► DelusionsDelusions

Occipital LobeOccipital Lobe

► Visual Visual HallucinatioHallucinationsns

► Visual Visual Perceptual Perceptual DistortionsDistortions

The Neuron: Key to The Neuron: Key to CommunicationCommunication

►100,000,000,000 Neurons100,000,000,000 Neurons

►Average Neuron has 10,000 Synapses Average Neuron has 10,000 Synapses (Connections)(Connections)

►More than 200 types of Neural CellsMore than 200 types of Neural Cells

Neural Cell VariationsNeural Cell Variations

Key types of Key types of Neurons:Neurons:

Signal TransmissionSignal Transmission

Signal Signal InterpretationInterpretation

Neural Cell AnatomyNeural Cell Anatomy

Synaptic TransmissionSynaptic Transmission

Neurotransmission Neurotransmission ActionAction

General Function of Cell may be General Function of Cell may be either:either:

Excitatory (sends signal)Excitatory (sends signal)

Inhibitory (stops signal)Inhibitory (stops signal)

Effects of NeurotransmitterEffects of Neurotransmitter

Stimulant: Increases Function of CellStimulant: Increases Function of Cell

Depressant: Decreases Function of CellDepressant: Decreases Function of Cell

Basic NeurotransmittersBasic Neurotransmitters

► DopamineDopamine Motor ControlMotor Control Emotional Emotional

StabilityStability Craving (Reward)Craving (Reward)

► SerotoninSerotonin Mood LevelsMood Levels Sleep PatternsSleep Patterns

► GABAGABA Inhibitory ControlInhibitory Control

► AcetylcholineAcetylcholine Motor Activity Motor Activity Parasympathetic Parasympathetic

SysSys

► NorepinephrineNorepinephrine Hypothalamus & Hypothalamus &

Limbic System Limbic System ConcentrationConcentration

► EndorphinesEndorphines Natural PainkillersNatural Painkillers

Example of Drug Effects Example of Drug Effects on Neurotransmitter on Neurotransmitter

LevelsLevelsTreatments for Depression – Treatments for Depression –

Serotonin LevelsSerotonin Levels► Tricyclic Drugs: Tricyclic Drugs:

Directly Activate Targeted Receptor SitesDirectly Activate Targeted Receptor Sites

► SSRI’s (Selective Serotonin Reuptake Inhibitors)SSRI’s (Selective Serotonin Reuptake Inhibitors) Blocks mechanism reabsorbing neurotransmitter Blocks mechanism reabsorbing neurotransmitter

from source cellfrom source cell

► MAOI’s (Monoamine Oxidase Inhibitors)MAOI’s (Monoamine Oxidase Inhibitors) Blocks enzymes from breaking down Blocks enzymes from breaking down

neurotransmitters in synaptic cleft.neurotransmitters in synaptic cleft.

N.I.D.A

How Drugs Effect the Brain:

THC Binding Sites

Emotion & Reward

Coordination

SensationJudgment

Memory(hippocampus)