Biopsych Test 2

Psychopharmacology

The study of how drugs affect the mind and behavior, specifically examining the interactions between pharmacological agents and the nervous system.

These 2 classes are what Psychopharmacology Drugs are classified in

Drugs of Abuse and Therapeutic Drugs

What is a Drug?

An exogenous chemical not necessary for normal cellular functioning that significantly alters the functions of certain cells of the body when taken in relatively low doses and what alters how neurons communicate with each other

Life Cycle of a Drug

Absorption—>Distribution—>Metabolism—>Excretion

Tissues

How drugs are administered and absorbed

Oral Administration

Most Common Form of Administration/Absorption

Intravenous injection

Fastest route, reaching the brain within a few seconds

Oral administration

absorbed into the blood through the digestive tract

CNS

Drugs that impact behavior exert effects mostly on or in cells of this

Distribution

Drug molecules must reach sites of action in the nervous system to produce changes in behavior

Lipid Solubility

Rate at which a drug enters the brain is determined by

How Lipid Solubility Impacts Drugs

correlates to how quickly it's actually able to pass through the blood brain barrier and then each its site of action to produce those effects.

Enzymes

Many drugs are metabolized and deactivated by

Brain, liver, and blood

where deactivation and metabolization of drugs by enzymes occurs in

Kidneys

where drugs are MOSTLY excreted by

Drug Effect

Changes we can observe in an individual’s physiological processes and behavior

Sites of Action

Drugs exert their effects only when they reach their

Therapeutic effects

intended, beneficial outcome of a drug

Adverse effects

Unintended and harmful response ranging from predictable but unwanted side effects to rare and unpredictable reactions

Analgesia (reduced sensitivity to pain)

Example of a Therapeutic Effect

Depress heart rate and respiration

Example of an Adverse Effect

Tolerance and Withdrawal Symptoms

Two types of effects in repeated administration

Tolerance

Decrease in Drug Effects; Seen in Many Drugs Commonly Abused

Withdrawal Symptoms

Symptoms are opposite of the effects of the drugs itself

Physical Dependence

Withdrawal Symptoms Indicate this

Placebo

an inactive substance that may have physiological or psychological effects; results from changes in motivation, expectation, or learning

Placebo Effect

a psychological and physiological phenomenon where a person's medical condition or symptoms improve after receiving an inert, fake, or sham treatment, driven by their expectation and belief that the treatment will help

Why Placebo Studies are Mandatory

The FDA made the RCT the sole arbiter of drug efficacy by the early 1970s

Why are Placebos important

helps investigate behavioral effects of drugs in humans

Agonists

facilitate postsynaptic effects; mimics or or enhances the effect of a neurotransmitter

Antagonists

block or inhibit postsynaptic effects; blocking or decreasing the availability of a neurotransmitter

Agonist and Antagonist

Drugs fall into one of two general classes, according to their effect on a neurotransmitter system:

Neruotransmitter

body’s chemical messengers that carry messages from one nerve cell to another target cell; such as another neuron, muscle, or gland

Glutamate’s CNS Function

Excitatory; interacts with other neurotransmitter systems

GABA CNS Function

Inhibitory, interacts with other neurotransmitter systems

Acetylcholine CNS Functions

Learning, memory, REM sleep

Dopamine CNS Functions

Voluntary movement, attention, learning, reinforcement, planning, problem solving

Norepinephrine/Epinephrine CNS Functions

Vigilance

Serotonin CNS Functions

Mood regulation, eating, sleep, dreaming, arousal, impulse control

Histamine CNS Functions

Wakefulness

Glutamate

Main excitatory neurotransmitter in brain and spinal cord

4 Major Types of Glutamate Receptors

NMDA receptor, AMPA receptor, and kainate receptor, glutamate receptor

NMDA Receptor

most common and controls a sodium channel

GABA

Primary inhibitory neurotransmitter with widespread distribution in brain and spinal cord

Chloride Channels

Controlled by GABA Receptors

3 components of an Emotional Response

Behavioral, Autonomic, Hormonal

Behavioral Emotional Response

Muscular movements (i.e., facial expressions, body language)

Autonomic Emotional Response

Quick mobilization of energy for vigorous movement (i.e., increased heart rate and breathing)

Hormonal Emotional Response

Reinforce autonomic responses

Epinephrine/Norepinephrine does this in Hormonal Emotional Response

helps to further increase blood flow to the muscles and cause nutrients stored in the muscles to be converted into glucose

Amygdala

Where the 3 Emotional Responses are Integrated

Sympathetic Nervous System

Where Autonomic Emotional Response is Located

Amygdala

Neurons here become active in emotionally relevant situations

Fear, pain, unpleasant or pleasant consequences

Emotional situations that have biological significance

Temporal Lobe

Where the Amygdala is located

Central Nervous System

Brain and Spinal Cord are contained here

Central Nervous System (CNS) and Parietal Nervous System (PNS)

What Nervous System Consists of

Motor Neurons and Sensory Neurons

What Parietal Nervous System (PNS) Consists of

Somatic Nervous System and Autonomic Nervous System

What Motor Neurons Include

Sympathetic Division and Parasympathetic Division

What the Autonomic Nervous System Consists of

Sympathetic Nervous System

Fight or Flight

Parasympathetic Nervous System

Rest or Digest

Central nucleus of the amygdala 

Most important part of the brain for expression of emotional responses provoked by aversive stimuli

Threatening Stimuli

Neurons in the Central Nucleus of the Amygdala are activated when these  are perceived

Central Nucleus of the Amygdala

Animals show physiological and behavioral signs of fear and agitation and people report feeling afraid

Central Nucleus of the Amygdala

Damage to this component leads to a reduction and abolition to various behaviors and emotional responses

What function Central Nucleus of the Amygdala associated with?  

primary output hub. It connects directly to the hypothalamus and brainstem to trigger involuntary "fight-or-flight" autonomic responses—such as changes in heart rate, blood pressure, and stress hormone release via the HPA axis

Lateral Nucleus of the Amygdala

this is associated with emotional conditioning

Lateral Nucleus of the Amygdala

Occurs when neutral stimulus is paired with emotion-producing stimulus and produces fear reactions

Memory

Damage to the Lateral Nucleus of the Amygdala interferes with the effects of

emotions on this

Ventromedial Prefrontal Cortex (vmPFC) Function

Associated with extinction of emotional conditioning

Ventromedial Prefrontal Cortex (vmPFC)

Inhibits or prevents fear responses

Extinction

Lesioning the vmPFC impairs

Extinction

This part of the behavioral process activates neurons in the Ventromedial Prefrontal Cortex

(vmPFC)

Extinction

the gradual weakening and disappearance of a conditioned response (CR). This happens when the conditioned stimulus (CS) is repeatedly presented without the unconditioned stimulus (US)

Aggression

involves threatening gestures or actual attack directed toward another animal

50 percent to 65 percent

Heritability of aggression ranges from this amount

Human Aggression

Recent studies have identified a variety of hereditary genes associated with this

Serotonin

Plays an inhibitory role in human aggression

SSRIs

can help to reduce irritability and aggressiveness 

Serotonin

Reduction of this neurotransmitter release is associated with aggression and other forms of antisocial behavior, including assault, arson, murder, and child abuse

Testosterone

Intermale aggressiveness increases at puberty when this hormone is secreted

Testosterone

this hormone does not automatically increase aggression but its relation to aggression is complex in humans

Testosterone

research on this hormone increases the behaviors that help an individual secure a high social status

Higher Level of Aggression.

higher testosterone leads to this in animals

Role of the Ventromedial Prefrontal Cortex (vmPFC) in Impulse Control

Inhibits emotional behavior, such as impulsive violence or aggression and is involved in moral decision making

Emotional Reactions

these guide moral judgments and decisions involving personal risks and rewards

Prefrontal Cortex (PFC)

this matures much later, during late childhood and early adulthood

Prefrontal Cortex (PFC)

development of this aids in control

Prefrontal Cortex (PFC)

as this matures, adolescents show increases in:

• Speed of cognitive processing

• Abstract reasoning ability

• Ability to shift attention from one topic

to another

• Ability to inhibit inappropriate responses

18th day after conception

Development of the human nervous system begins around this time

By the 21st day

the neural tube is formed by this time

Stem cells

these line the inside of the neural tube and then give rise to the cells of the CNS

Prenatal Brain Development

Once neurons have migrated to their final locations, they begin forming connections with other neurons

Apoptosis (or pruning)

occurs (and continues postnatally) as the axons of approximately 50 percent of the new neurons do not form. synaptic connections, so they die

Postnatal Brain Development

The human brain continues to

develop for at least two to three

decades following birth

Brains develop so that different

regions of the cerebral cortex

perform specialized functions

Subtle changes continue to occur

throughout life

ASD Heritability

strong; caused by a wide variety of rare mutations, especially those that interfere with neural development and communication

Evidence of ASD Environmental Factors

Advanced parental age at time of

conception

Prenatal exposure to air pollution or

certain pesticides

Maternal obesity, diabetes, or immune

system disorders

Extreme prematurity or very low birth

weight

Any birth difficulty leading to periods of

oxygen deprivation to the baby’s brain

ASD Brain Growth

MRI studies show that these are slightly smaller and show more rapid growth by by 10 % in 2 to 3 years

ASD White Matter Changes

containing short-range axons is increased but volume containing long-range axons that connect distant regions of the brain wasnt