Unit 1 Part 1

Module 1.1:

Psychology’s biggest issues: are our human traits present at birth (nature) or do they develop through experience (nurture)

Nature	Nurture
Our traits are a result of genetics	Our traits are a result of our experience (how we were raised, parents, siblings, community, religion etc.)

Today’s science views traits + behaviors as arising from interaction of nature & nurture

Evolutionary Psychology: study of evolution of behavior & mind; uses principles of natural selection

Charles Darwin’s theory of Natural Selection: principle that inherited traits enable an organism to survive + reproduce in particular environment will most likely be passed onto succeeding generations
Behavior Genetics: study of relative power / limits of genetic + environmental influences on behavior (how genetics / environment influence behavior)

Understanding Human Nature:

Evolutionary psychologists use Darwin’s principle of natural selection to understand behavior + mental processes.
Organism’ varied offspring compete for survival --- mutation (random error in gene replication that leads to a change)
Certain biological and behavioral variations increase organisms; reproductive & survival chances
Offspring that survive more likely to pass on genes
Eugenics: aims to “eradicate” genetic defects & improve genetic makeup through selective human breeding

Environment and Heredity:

Behavior genetics: explores genetic + human environment basis of human differences
- Environment: NONgenetic influence (i.e. prenatal nutrition, experiences of people and things around us)
- Heredity: genetic transfer of characteristics from parent → offspring
Ex: 2 people may have gene for high intelligence level, but individual with lack of stimulation to academically excel may not reach full potential, while individual constantly motivated intellectual will be more likely to intellectually excel

Genes: Our Life Code:

Genes: biochemical units of heredity
Genome: entire set of DNA / genetic information found in organism
- humans + chimps ~96% the same genetically
no one single gene that will predict your intelligence, personality, or sexual orientation

Twins & Adoption Studies:

1 of ways to study nature vs. nurture argument
Identical (monozygotic) twins: individuals who developed from 1 fertilized egg that split in 2, creating 2 genetically identical organisms; may not always have equal number copies of genes repeated in genome
Fraternal (dizygotic) twins: individuals who developed from separate fertilized eggs; genetically no closer than ordinary siblings but shared prenatal environment
Twin studies: allow researchers to examine role of genes in development of trait or disorder; comparisons between monozygotic twins & dizygotic twins conducted to evaluate degree of genetic + environmental influence on specific trait
Studies have shown that environment shared by a family’s children has little impact on their personality--- just because you’re raised in same environment does not mean you will have similar personality as your parents/siblings

Gene-Environment Interactions:

Interaction: interplay that occurs when effect of 1 factor (environment) depends on another factor (heredity)
- Example: If you walk all summer barefoot your feet will become more callused. Your friend wears shoes and is tender-footed ---biological adaptation to environmental changes
Epigenetics: study of molecular mechanisms by which environments can influence genetic expression
- Example: If a child is sleep deprived or nutritionally deprived they might not reach their biological/genetic height

Module 1.2:

Nervous System: body’s speedy electrochemical communication network, consisting of all nerve cells of peripheral & central nervous system

Central nervous system (CNS): brain, spinal cord
Peripheral nervous system (PNS): sensory & motor neurons connecting CNS to rest of body

Nerves: bundle of axons that form neural cables connecting CNS with muscles, glands, sensory organs

Sensory (afferent) neurons: carry incoming information from body’s tissues and sensory receptors to brain, spinal cord
Motor (efferent) neurons: carry outgoing information from brain, spinal cord to muscles and glands
Interneurons: within brain, spinal cord; communicate internally & process information between sensory inputs and motor outputs

Autonomic Nervous System: division of PNS that controls glands, muscles of internal organs; involuntary (without conscious thought) — heart beating, lungs breathing

Somatic Nervous System (AKA Skeletal Nervous System): division of PNS that controls body’s skeletal muscles

Sympathetic Nervous System: division of

autonomic nervous system that arouses

body, mobilizing its energy; “fight or flight”

Parasympathetic Nervous System: division of autonomic nervous system that calms body, conserving its energy; “rest and digest”; brings cody back to homeostasis

Central Nervous System:

Brain: controls most of 5 functions of body, including awareness, movement, thinking, speech, 5 senses

Spinal cord: extension of brain; carries messages to / from brain to rest of body

Reflex: simple, automatic response to sensory stimulus; Ex: knee-jerk stimulus

Module 1.3a:

Neuron: nerve cell; basic building block of nervous system

Cell body: contains cell nucleus

Dendrites: receive messages from terminal branches of sending neuron

Glial cells (“glue of Nervous System”): type of cell that provides physical + chemical support to neurons & maintains their environment

Multiple Sclerosis	Myasthenia Gravis
Autoimmune disorder; body’s immune system attacks + destroys myelin sheath of neurons → disrupts signals nerves send to body; diminishes muscle control, can impair cognition	Progressive autoimmune disease; body produces antibodies against / attacks acetylcholine receptors at neuromuscular junctions (connection point between motor neuron + muscle fiber); symptoms = muscle weakness in eyes, mouth, throat, limbs

Neural Impulse:

Action potential: neural impulse; brief electrical charge that travels down axon (neurotransmitter transported from dendrites → terminal branches of axon → next neuron); will only be generated when excitatory impulses > inhibitory impulses

Threshold:level of stimulation required to triggeraction potential
Refractory period: brief resting pause after neuron has fired / initiated action potential (more difficult / impossible for neuron to produce another action potential during this time); subsequent action potentials cannot occur until axon returns to resting state; neuron cannot “re-fire” until it reaches refractory period; prevents action potential from happening too quickly again + signal moving backwards
All-or-Nothing response: neuron’s reaction of either firing or not firing depending on whether threshold is met (no partial responses); for a certain neuron, action potential stays the same regardless of strength of stimulus

How neurons communicate:

Synapse (a.k.a. Synaptic gap, synaptic cleft): junction between axon tip of sending neuron + dendrite / cell body of receiving neuron
Neurotransmitters: chemical messengers that cross synaptic gap between neurons; released by sending neuron → neurotransmitters travel across synapse → bind to receptor sites of receiving neuron (influence whether receiving neuron will generate a neural impulse)
Reuptake: neurotransmitters reabsorption by sending / presynaptic neuron (prevent accumulation of neurotransmitters in synapse → excessive / prolonged stimulation of postsynaptic neuron, terminates signaling by neurotransmitter once signal has been transmitted to postsynaptic neuron, allows neurons to recycle neurotransmitters)

Neurotransmitters:

Neurotransmitter:	Function:	Examples of malfunction:
Acetylcholine	excites skeletal muscles; inhibits heart action; memory	Alzheimer’s disease
Dopamine	movement; learning: attention; motivation, reward	Parkinson's disease (too little); Schizophrenia (too much); Substance abuse
Serotonin	sleep; arousal / alertness; mood; eating; pain perception	Depression; Obsessive Compulsive Disorder; Some eating disorders; Chronic pain
Norepinephrine	sleep; arousal / alertness; mood	Depression
GABA	chief inhibitor; regulates arousal / alertness	some anxiety disorders; some seizure disorders
Glutamate	chief excitatory neurotransmitter; many diverse functions	Neural death following head injuries
Endorphins	pain suppression	Some indication of link to mood
Substance P	carries pain signals	Some indication of a link to depression

Agonist vs. Antagonist:

Agonist: molecule that ↑ action of neurotransmitter; usually has very similar structure to neurotransmitter allowing it to mimic actions of neurotransmitter by binding to specific brain receptors
- Ex: morphine binds to neurons to heighten pleasure / decrease pain
Antagonist: molecule that inhibits or blocks action of neurotransmitter
- Ex: memantine blocks glutamate receptors in brain, helping reduce excitotoxicity (neuronal damage; associated with neurodegenerative diseases)

Endocrine System:

Body’s “slow” chemical communication system; set of glands, fat tissue that secrete hormones into bloodstream
- Hormones: chemical messengers manufactured by endocrine glands that travel through bloodstream + affect other tissues
Hypothalamus: secretes hormones that stimulate / suppress release of hormones in pituitary gland

Hormones	Functions
Adrenaline	hormone / neurotransmitter secreted by adrenal glands typically during stressful, exciting, or highly emotional situations
Leptin	hormone released by fat cells; works together with ghrelin to regulate appetite
Ghrelin	hormone produced primarily by gastrointestinal tract; helps to regulate appetite
Melatonin	hormone released primarily by brain’s pineal gland; regulates body’s sleep-wake cycle
Oxytocin	produced by hypothalamus, released by pituitary gland; known as “love hormone”; plays key role in socializing, romantic relationships, parent-child bonding

Module 1.3b:

Psychoactive Drug: chemical substance that alters brain, causing changes in perceptions + moods (i.e. seeing things that aren’t there, hearing things that aren’t there, distance / depth perception)

Substance Use Disorder: disorder characterized by continued substance use despite resulting life disruption; Ex: someone who continuously uses alcohol even if it may cost them their family, job, money etc.

Near-death experience: altered state of consciousness reported after “close brush with death”; often similar to drug-induced hallucination

Tolerance & Addiction:

Tolerance: diminishing effect with regular use of same dose of drug → forces user to UP DOSAGE in order to experience drug’s effect; can also be built up with medication
Addiction: compulsive substance use that continues despite harmful consequences; considered psychological disorder
- Gambling, video games, other behaviors = can be considered addictive
Withdraw: discomfort and distress that follows discontinuing an addictive drug / behavior; physical / psychological symptoms after coming off a drug

Depressants: drugs that reduce neural activity and slow body functions
Drug	Plesuable effects	Negative after effects
Alcohol	Initial high followed by relaxation + disinhibition; may not be able to do certain things after using	Depression, memory loss, organ damage, impaired reactions
Barbiturates (tranquilizers)	Reduce anxiety, can be used to help other disorders	Depress NS activity, can be prescribed to induce sleep / reduce anxiety, in large doses can impair memory & judgment
Opiates (Heroin)	Rush of euphoria, relief from pain, mimics effects of endorphins / norepinephrine	Depressed physiology, slows down NS (slower cognitively, reduced memory), agonizing withdrawal once you come off it & don’t have another supply

Stimulants: drugs that excite neural activity & speed up body functions
Drug	Plesuable effects	Negative after effects
Caffeine	Increased alertness, wakefulness	Anxiety, restlessness, insomnia in high doses; uncomfortable withdrawal (caffeine headache)
Nicotine	Arousal, relaxation, sense of well-being	Heart disease / cancer, lung cancer
Cocaine	Rush of euphoria, confidence, energy	Ramps up body so much it can cause cardiovascular stress (overworking heart), suspiciousness, depressive crash
Methamphetamine	Euphoria, alertness, energy	Irritability, insomnia, hypertension, seizures

Hallucinogens: psychedelic drugs that distort perceptions & evoke sensory images in absence of sensory input
Drug	Plesuable effects	Negative after effects
Ecstasy (MDMA): mild hallucinogen, also stimulant	Emotional elevation, disinhibition	Dehydration, overheating, depressed mood, impaired Cognitive, immune functioning
LSD	Visual “trip” (seeing things that are not there)	Risk of panic (as a result of “bad” trip)
Marijuana (THC)	Enhanced sensation, relief of pain, distortion of time, relaxation	Impaired learning and memory, increased risk of psychological disorders (correlation between those using marijuana at young age + development of schizophrenia)

Module 1.4a:

Biological Psychologist:

Phrenology: proposed by Franz Gull; idea that studying bumps on skull would reveal person’s mental abilities & character traits; over time, proved to be FALSE
***Biological Psychologist (a.k.a. behavioral neuroscientist, neuropsychologist, behavior geneticist, physiological psychologist, or biopsychologist): studies link between biological (genetic, neural, hormonal) + psychological processes

Biopsychosocial Approach:

integrated approach; incorporates biological, psychological, & social-cultural levels of analysis
Levels of analysis: differing complementary views (biological to psychological to social-cultural) / using different approaches to analyze given phenomenon

Power of Neuroplasticity:

Neuroplasticity: brain’s ability to change + adapt to change, especially during CHILDHOOD, by reorganizing or building new pathways based on experience after damage

Types of Neural Measures:

	How it works:	Function:
Electroencephalogram	measures electrical activity in brain by placing electrodes on scalp	used to track real-time brain activity + diagnose conditions (epilepsy, sleep disorders); monitor general brain function; often used in sleep studies
Magnetoencephalography	Head coil measures magnetic fields generated by electrical activity / natural electric currents in brain	used to map brain function -- surgical planning,studying sensory, cognitive, and motor processes; often used with PTSD
Computed Tomography	use X-rays to create cross-sectional images of brain that may locate brain damage; (faster than MRI, exposes patients to radiation)	provides good structural detail; used in child brain injuries,
Positron emission tomography	tracks location fo temporarily radioactive tracer (form of glucose) in brain of person performing specific task; uses radiation	shows brain function; useful for detecting diseases / monitoring function;
Magnetic resonance imaging	People lie down / sit in chamber; uses strong magnetic fields + radio waves to produce detailed images of brain's soft tissue / brain’s structure; (slower than CT, offers more detail)	diagnosing structural abnormalities, brain injury, planning surgeries
Functional magnetic resonance imaging	measures changes in blood flow to different brain regions by comparing continuous MRI scans	Shows brain function + structure; mapping brain activity, studying cognitive processes (memory, decision-making), identifying brain regions involved in specific tasks

Module 1.4b:

The Brain:

Hindbrain: consists of medulla, pons, cerebellum; directs essential survival functions (breathing, sleep, wakefulness, coordination, balance)

Midbrain: found atop brainstem; connects hindbrain with forebrain, controls some motor movement, transmits auditory & visual information

Forebrain: consists of cerebral cortex, thalamus, hypothalamus; manages complex cognitive activities, sensory & associative functions, voluntary motor activities

**lower brain centers = hindbrain + midbrain

Amygdala	Linked to emotion; veery primitive section of brain
Hippocampus	Linked to conscious memory
Limbic system	Neural system located mostly in forebrain (below cerebral hemispheres); includes amygdala, hypothalamus, pituitary gland
Corpus callosum	Axon fibers connecting 2 cerebral hemispheres
Thalamus	relays messages between lower brain centers & cerebral cortex
Hypothalamus	Controls maintenance functions (easting); helps govern endocrine system; linked to emotion & reward
Pituitary gland	Master endocrine gland
Reticular formation (reticular activation system)	Helps control arousal / alertness
Pons	Helps coordinate movement & control sleep
Medulla	Controls heartbeat, breathing
Spinal cord	Pathway for neural fibers traveling to / from brain; controls simple reflexes
Cerebellum (“little brain”)	Coordinates voluntary movement, balance; supports learning & memories of such
Cerebral cortex	Ultimate control & information-processing center

The Lobes of the Brain:

Association areas: reas of cerebral cortex not involved in primary motor functions, but involved in higher mental functions (learning, remembering, speaking, thinking)

Motor cortex: involved in planning, controlling, execution of voluntary movements

Somatosensory cortex: interprets tactile stimuli, such as touch, temperature, pain, proprioception (awareness of body position)

Module 1.4c

Response to Damage:

brain’s ability to repair itself / create new neural pathways
Neuroplasticity: ability of neural networks in brain to change thru growth / reorganization by modifying strength of existing synapses + forming new synaptic connections; can occur after serious damage, especially in young children, can help those with vision or hearing loss (brain enhances other sensory signals / inputs)
Neurogenesis: formation of new neurons

Split Brain Procedure:

Corpus Callosum: large band of neural fibers connecting 2 hemispheres + carrying messages between them; allow messages to be passed between 2 hemispheres → brain works as cohesive unit
Split Brain: condition resulting from surgery that separates brain’s 2 hemispheres by cutting fibers (mainly those of corpus callosum); creates 2 separate brains that can no longer communicate → independent functioning of each hemisphere; commonly used to treat severe epilepsy
- Split brain patients often have difficult time speaking fluently when objects presented in left visual field → right hemisphere is non-verbal + interprets left visual field

Left hemisphere

Right hemisphere

- right visual field

- controls right side of body

- verbal

Ex: patient can state whatever in right visual field

- left visual field

- controls left side of body

- non-verbal

Ex: patient can point w/ left hand to whatever in left visual field

Left vs. Right Hemisphere traits:

Left	Right
Language !! Logic Critical thinking Numbers Reasoning	Recognize faces Express / read emotions Create music Appreciate color Use imagination Be creative / intuitive visual-spatial information processing