Intro to Psychology: Key Concepts

Psychology as a Science

• Psychology employs an empirical approach, relying on observation and experimentation for evidence-based conclusions.
• The scientific attitude in psychology involves curiosity, skepticism, and humility.

Birth of Modern Psychology

• Wilhelm Wundt's work on the "atoms of the mind" in 1879 is considered the birth of modern psychology.

Psychology's First Schools of Thought

• Structuralism (Edward Titchener) aimed to break down the mind into basic parts through introspection.
• Functionalism (William James), influenced by Darwin, focused on the purpose of thoughts, feelings, and behaviors.
• Behaviorism (John Watson & B.F. Skinner) concentrated on observable and measurable behaviors.
• Psychoanalytic psychology (Sigmund Freud) emphasized unconscious drives, urges, conflicts, and repression.
• Humanistic psychology (Abraham Maslow and Carl Rogers) highlighted the needs for love, acceptance, and potential for growth.
• Cognitive psychology studies how we process and remember information.
• Cognitive neuroscience explores the brain activity underlying mental processes.

Psychology Defined

• Psychology is defined as the science of behavior and mental processes.

Nature vs. Nurture

• The nature-nurture debate examines the extent to which traits are determined by genes (nature) versus environment and experience (nurture).

Biopsychosocial Approach

• The biopsychosocial approach integrates biological, psychological, and environmental factors.
• Biological level includes genes, brain, neurotransmitters, survival, reflexes, and sensation.
• Psychological level includes thoughts, emotions, moods, choices, traits, and motivations.
• Environmental level includes social influences, culture, education, and relationships.

Hindsight Bias

• Hindsight bias is the tendency to believe, after learning an outcome, that one would have predicted it.

Overconfidence

• Overconfidence involves overestimating our performance, skills, and accuracy of knowledge.

Perceiving Order in Random Events

• Humans tend to seek patterns and perceive order even in random events.
• Thinking you can predict a random series is a common error.

Psychology Science in a Post-Truth World

• Modern culture often prioritizes emotions and personal beliefs over objective facts.
• Social media can create echo chambers of like-minded individuals.

The Scientific Method

• The scientific method is a self-correcting process for evaluating ideas through observation and analysis.
• It includes:
  • Theory: an explanation using principles that organize observations and predict behaviors or events.
  • Hypothesis: A testable prediction consistent with the theory.
  • Operational definitions are precise statements of procedures used in a research study.
  • Replication: repeating a research study to see whether the basic finding can be reproduced.

Research Types/Goals

• Descriptive research aims at systematic, objective observation of people.
  • Case study: examining one individual or small group in depth.
  • Naturalistic observation: observing behavior in natural settings without intervention.
  • Surveys and interviews: gathering information through self-report.

Correlation

• Correlation is a measure of how closely two factors vary together and how well one predicts the other.
  • Scatter plots are used to visualize correlations.
  • Positive correlation (0 to +1.00): both variables increase together.
  • Negative correlation (0 to -1.00): as one variable increases, the other decreases.

Experimentation

• Experimentation involves manipulating one factor to determine its effect on a behavior or mental process.
  • Experimental group: receives the treatment.
  • Control group: does not receive the treatment, may receive a placebo.
• Placebo effect: experimental effects caused by expectations about the intervention.
• Independent variable (IV): the factor manipulated by the experimenter
• Dependent variable (DV): the outcome factor.
• Confounding variables: factors other than the IV that may affect the DV.

Value of Statistics

• Statistics help present data accurately and draw conclusions.
• Measures of central tendency include:
  • Mode: the most frequently occurring score.
  • Mean: the average score.
  • Median: the middle score.
• Range: the difference between the highest and lowest scores.
• Standard deviation: a measure of how much scores vary around the mean.
• Normal Curve: a symmetrical bell-shaped curve that describes the distribution of many types of data

Drawing Conclusions from Data

• Important factors when drawing conclusions from data
  • Is the difference reliable?, unbiased sampling (representative), consistency (responses/observations), many data points.
  • Is the difference significant?, when your data is reliable and the difference between the groups is large.

Neuroplasticity

• Neuroplasticity is the brain’s ability to change by reorganizing in response to new experiences.

Neurons and Neuronal Communication

• Cell body: the cell's life support center.
• Dendrites: receive messages from other cells.
• Axon: passes messages away from the cell body to other neurons, muscles, or glands.
• Terminal branches of axon: form junctions with other cells.
• Neural impulse (action potential): electrical signal traveling down the axon.
• Myelin sheath: covers the axon and speeds neural impulses.
• Glial cells: support, nourish, and protect neurons and assist in neural transmission.

Action Potential

• Is a neural impulse that travels down an axon like a wave.

Neuron Signaling

• Excitatory signals encourage signal sending.
• Inhibitory signals tell the neuron to stay quiet.
• A neuron "fires" if excitatory signals are stronger than inhibitory signals and reach a threshold.
• All-or-nothing response: a neuron either fires fully or not at all.

Neuron Communication

• Action potential travels down the axon to terminal branches.
• Synapse (synaptic cleft): the gap between the sending and receiving neurons.
• Neurotransmitters: chemical messengers that carry signals across the synaptic gap.
• Reuptake: recycling process where leftover neurotransmitters are taken back by the sending neuron.

Types of Neurotransmitters

• Dopamine: affects emotions and learning.
• Serotonin: linked to mood and sleep.
• Acetylcholine: helps with muscle movement and memory.
• Endorphins: reduce pain and boost pleasure.

Neurotransmitters Work

• Agonists mimic neurotransmitters to increase their effect.
• Antagonists block receptor sites, preventing neurotransmitters from working.

The Nervous System

• Central Nervous System (CNS): brain and spinal cord – main control center.
• Peripheral Nervous System (PNS): nerves outside the CNS; gathers information and sends instructions.
• Sensory neurons: bring information from the body to the CNS.
• Motor neurons: carry instructions from the CNS to muscles and tissues.
• Interneurons: process sensory input and decide on motor output within the brain and spinal cord.

Parts of the Nervous System

• PNS
  • Autonomic nervous system: controls automatic functions like breathing and heartbeat.
  • Sympathetic system: activates fight or flight response.
  • Parasympathetic system: helps calm down – rest and digest.
  • Somatic nervous system: controls voluntary movements.
• CNS
  • The brain.
  • About 128 billion neurons.
  • Makes up 2% of body weight but uses 20% of energy.
  • Neurons form neural networks that strengthen with practice and learning.
  • How learning works - "Neurons that fire together, wire together".

Adult Brain Facts

• 128 billion neurons, 2% of body weight, 20% of body's energy.

Interneurons

• The spinal cord is full of Interneurons
• Spinal interneurons trigger reflexes before the brain is even aware.

The Endocrine System

• Relies on a set of glands that produce hormones
• Hormones delivered through the bloodstream
• Adrenal Glands
  • Hormones such as epinephrine (adrenaline), norepinephrine, and cortisol
  • Fight or Flight response
  • Increased heart rate, blood pressure, and blood sugar and ENERGY FOR THE FIGHT OR FLIGHT
• The Pituitary Gland - “master gland”
  • Regulates other glands
  • Produces growth hormone (especially during sleep) and oxytocin (feel-good hormone)

Areas of the Brain and Their Functions

• Older/less complex structures coordinate the body
• Limbic system manages emotions and connects thought to body
• Cerebral cortex integrates information
• Brainstem - Pons
  • Help coordinate automatic and unconscious movements
  • Control sleep (primitive level)
• Brainstem - Medulla
• Controls most basic functions: Hearbeat and breathing
• Most nerves cross in the brainstem - Most nerves to and from each side of the brain connect with the body's opposite side.
• Thalamus - “Sensory switchboard”
  • Receives information from senses and sends it to higher brain regions
• Reticular formation
  • Enables alertness and arousal
  • Without it, you can be in a coma and never wake up
• Cerebellum (little brain) Enables nonverbal learning and memory Muscle memory Helps modulate emotions Coordinates voluntary movement (different than reflexes)
• The limbic (border) system
  • Hippocampus
  • Processes conscious memories
  • Works with the amygdala to form emotionally charged memories
• Amygdala
  • Processes emotions (intense) - rage and fear
  • Amygdala damage → reduced arousal to fear and anger arousal stimuli (they don't feel emotions) - “I should feel scared,” but they are not
  • When (-) events energize the amygdala - they become more memorable
• Hypothalamus (master of the master gland)
  • Body maintenance, making sure everything is on track
  • Regulates body temperature, hunger, thirst, and sexual behavior
  • Directs the endocrine system through messages to the pituitary gland
  • Cerebral Cortex
  • Wrinkled to create more surface area
  • 20-23 billion neurons
  • 300 trillion synaptic connections
  • The brain has right and left hemispheres
  • Frontal lobes (planning, judgment
  • Parietal lobes (sensory input)
  • Occipital lobes (visual areas)
  • Temporal lobes (sound, speech - auditory areas)

Functions of the Cortex

• More complex animals have more cortical space devoted to association/integration of information
• Frontal Lobes Association Areas
  • Judgment, planning, impulse inhibition, processing new memories
• Whole-brain association Activity -Complex activities require communication among association areas across the brain
• Severed brain and spinal cord neurons usually do NOT regenerate
• Neural tissue can reorganize → form new connections, reassign existing networks
  EXAMPLE - constraint-induced therapy gets the “bad” side working again

Right-Left Hemisphere Differences

• Left Hemisphere

  • Thoughts and logic
  • Details
  • Language - words and definitions (literal)
  • Speech
  • Calculation

• Right Hemisphere

  • Feelings and intuition
  • Recognizing faces
  • Language - tone, inflection, context (inferences)
  • Perceiving emotion
  • Self-awareness

• Consciousness

  • Our subjective awareness of ourselves and our environment
  • Cognitive neuroscience
  • The study of the brain activity linked with our mental processes

• Selective Attention

  • Focusing conscious awareness of a particular stimulus
  • 5 senses: 11,000,000 bits of information per second
  • The “important stuff” captures your attention

• Inattentional Blindness

  • Our failure to see visible objects when our attention is directed elsewhere
  • Attention is powerfully selective
  • Your conscious mind is in one place at a time

• Dual Processing - The 2 track mind

  • Conscious “high” road
  • Our minds take deliberate actions we know we are doing (REFLECTIVE) Unconscious low road
  • Our minds perform automatic actions often without being aware of them (INTUITIVE) Automatic processing - conscious “high” track says I saw a bird
  • Unconsciously, we see color, motion, form, and depth

Parallel vs Sequential Processing

• Everyday thinking, feeling, and acting operate outside our conscious awareness.
• Unconscious parallel processing is fast and handles routine tasks.
• Conscious sequential processing is best for solving new problems, focusing on one thing at a time.

Sleep and Biological Rhythms

• The circadian rhythm is the body's natural 24-hour cycle, influencing body temperature, arousal, and mental sharpness.
• About every 90 minutes, we pass through four distinct sleep stages
• Sleep Stages and Sleep Cycle
  • Alpha waves - awake but relaxed
  • Falling asleep
  • Change from alpha to NREM-1
  • Non-REM sleep stages - getting deeper into sleep - not dreaming yet REM sleep Dreams occur during periods of wild brain activity and Rapid Eye Movements Heart rate rises, and breathing becomes rapid “Sleep paralysis” occurs when the brainstem blocks the motor cortex messages and the muscles don't move. Sometimes known as paradoxical sleep, the brain is active,e but the body is immobile.

Sleep Affects

• Sleep Cycle affected by: Amount and pattern of sleep is affected by biology, age, culture, and individual variation. age - in general, newborns need 16 hours of sleep - adults need 7-9 hours. individual (genetic variation) culture - Americans sleep less than others and less than they used to, perhaps because of the use of light bulbs Stress impacts sleep
  The circadian rhythm is complex to shift (jet lag) This rhythm can be affected by light Decreased melatonin production Artificial light delays sleep and affects sleep quality

Why We Sleep Reasons

• Sleep restored and defended to protect from predators
• Sleep restores the immune system and repairs the brain and body
• Sleep facilitates creative problem-solving
• Sleep is the time when growth hormones are active
• A good night's sleep can dramatically improve your athletic ability
• Respect sleep as your tool for high IQ and good learning

Effects of Sleep Loss/Deprivation

• Inadequate sleep increases likelihood of: Lose brain power, Gain weight, Get sick, Be irritable, depressed Feel old
• Sleep loss results in more accidents, probably caused by impaired attention and slower reaction time

Sleep Hygiene Tips

• Turn the lights low and turn the screens off
• Eat earlier and drink less alcohol and caffeine
• Sleep on a consistent schedule
• Exercise (but not in the late evening)
• Embrace a wind-down routine
• Don't stay in bed awake
• Manage stress

Altering Consciousness Drugs Facts

• Psychoactive drugs are chemicals which Alter perceptions and moods.
• Effects of psychoactive drugs - “a drug's overall effect depends on its biological effects AND the user's expectations.”
• Tolerance of drugs
  • Users develop tolerance as brain chemistry adapts. More of the substance is needed over time to achieve the same effect.
  • Increased doses raise the risk of addiction and substance use disorder.
• Addiction Results
  • Results from increased doses of psychoactive drugs
  • It leads to craving the drug, continuing use despite adverse effects, and withdrawal struggles
  • Once addicted, people want the drug more than they like it.

Types of Altering Consciousness Drugs

• Depressants- reduce neural activity and slow body functions
• Stimulants - dilated pupils, increased breathing and heart rate, increased blood sugar, decreased appetite
• Hallucinogens Marijuana/THC amplifies sensations, likely contributes to impaired attention, likely contributes to impaired learning, likely contributes to impaired memory

Factors Turning Drug Use To Dependence

• Biological influences - genetics; deficiencies in the brain's dopamine reward system
• People rarely abuse drugs if they understand the physical and psychological costs - feel good about themselves and the direction their lives are taking - and are in a peer group that disapproves of using drugs. Psychological factors - lack of close, secure attachments - hopelessness - depression - trauma - significant stress or failure Social influences - media glorification - observing peers - what they think their friends are doing

Behavior Genetics

• Behavior genetics study of power and limits of GENETIC and ENVIRONMENTAL influences on behavior
• Genes are building blocks of heredity and development
• the human genome includes 46 chromosomes in 23 matched sets (half a set of chromosomes from each biological parent)
• altogether, you have about 20,000 genes
• Genes NOT blueprints, they are molecules that can direct the assembly of proteins that build the body and can be turned on and off by environmental events.
• different traits are polygenetic - they are influenced by many genes of minor effects
• IDENTICAL TWINS = same-sex only (Personality traits such as extraversion and neuroticism)
• FRATERNAL TWINS = same/opposite sex (no more genetically alike than other siblings)

Twin and Adoption Studies

• Twin studies assess the impact of nature and nurture by examining traits of siblings vs. identical twins.
• Adoption studies examine the similarity of adopted children to biological versus adoptive relatives.
• Adopted children are more similar to their genetic relatives rather than nurture relatives.
• People who grow up together - whether biologically related or not - do NOT much resemble one another in personality
• A shared family environment has little discernible impact on a child's personality
• Despite the strong impact of genetics on personality, parenting influences religious beliefs, political beliefs, manners, attitudes, and values

Temperament and Heritability

• A person's characteristic emotional reactivity and intensity are genetically influenced,NOT CAUSED BY PARENTING.
• The heritability of a trait is the amount of variation in the population, which is explained by genetic factors, DOES NOT tell us the proportion of genes contributing to the trait for any person.

Molecular Genetics

• Molecular genetics studies the structure and function of genes. Molecular behavior genetics - how do the structure and function of genes interact with our environment to influence behavior?
• Environments can trigger or block genetic expression.
• Genes are self-regulating (they react).
• Examples of self-regulation in humans, obesity in adults can turn off weight regulation genes in offspring
• Epigenetics is the study of how the environment acts on the surface of genes to alter their - activity (without DNA change), Diet - drugs - stress - neglect - abuse

Evolutionary Psychology

• Humans are naturally adaptable Paradox: Even though our genes shape us, they also make us flexible and able to change based on our environment.
• Evolutionary psychology studies how our behaviors and minds evolved using natural selection (survival of the fittest)
• Evolutionary psychology looks at what makes us similar across all cultures and generations.
• Natural Selection Explained: A species has a variety of genes that create different traits. Some traits help individuals survive better in their environment. Those individuals are more likely to reproduce, passing on their successful traits. Over generations, these traits become more common.
• Artificial Selection: Domesticated Foxes Like wolves evolved into domestic dogs. Humans can shape traits in other species through controlled breeding.

How Evolution Shapes Human Behavior

• Babies develop a fear of strangers at 9-13 months, which helps prevent them from wandering into danger.
• People quickly develop fears of snakes, spiders, darkness, and heights due to ancestral threats.
• Men may be more attracted to youth and fertility, while women often value stability, protection, and loyalty.
• Critiquing Evolutionary Psychology In cultures with greater gender equality, men and women behave more similarly. Culture matters: Women in some societies are more open to casual relationships, and men can be socialized to prefer commitment.

The Role of the Environment

• Rats raised in an enriched environment (lots of toys, exercise, and stimulation) had bigger brains and more neural connections. Unused connections are "pruned" away (like trimming a tree). For example, if you learn to play piano early, your brain strengthens those pathways. If you stop practicing, those connections weaken.

How Parenting Shapes Development

Does parenting have a significant impact? Extreme cases (neglect, abuse) -> YES, parenting has a significant impact. For “average” parents, The effects aren’t as strong as we think. Parents influence their kids, but genes and environment play huge roles, too. What is Culture? Culture = Shared beliefs, values, and behaviors passed down through generations.

• The cultural differences and differences in gender.

Culture Influences On Gender

• Individualist cultures value independence and finding unique identity, while collectivist cultures value interdependence and blending into group identity.
• Gender: Socially Influenced Characteristics
• Question is raised genetic differences or role differences nurtured by culture

Difference Between Genders

• Biological differences, mental and behavioral health
• Men more likely to be physically aggressive and commit crimes
• Men socially dominant
• Gender and Social Connection: Play
• Social Communication and Connectedness Men and women use communication differently Women, more than men, turn to others for support “tend and befriend”

Nuture of Gender Roles

How do we learn GENDER? Social learning theory Gender role behavior is learned through observation, imitation, rewards, and punishments Despite parenting influences, children may drift toward what feels right to them Gender schemas organize our boy-girl characteristics, children categorize everything including people and are motivated to conform

Influences On You

• Biological influences, Physiological influences, Social-cultural influences, YOU CAN SHAPE YOUR DEVELOPMENT
• If their genes and hormones predispose males to be physically aggressive than females, cultures can amplify this gender difference through norms that reward macho men and gentle women

Explore fundamental concepts in psychology, including the empirical approach, behaviorism, and the biopsychosocial model. Understand cognitive neuroscience, common biases, the nature-nurture debate, and brain structures. This covers essential topics in psychological research and theory.