Comprehensive Psychology & Neuroscience: Key Concepts and Research Methods

Psychology

derived from physiology and philosophy — science of behavior and mental processes

Psychoanalytic approach

focuses on unconscious processes and childhood experiences

Behavioral approach

focuses on learned and reinforced behaviors

Humanistic approach

emphasizes free will, choice, and self-actualization

Cognitive approach

focuses on perceptions and thought processes

Evolutionary approach

focuses on genetic and adaptive explanations for behavior

Biological approach

focuses on the brain and neurotransmitters

Sociocultural approach

focuses on the influence of society and culture on behavior

Biopsychosocial approach

combination of biological, psychological, and social factors

Basic research

research conducted to increase knowledge (e.g. rats in a maze)

Applied research

research conducted to solve real world problems

Psychologist

holds MS or PhD; conducts research or counseling but cannot prescribe medication

Psychiatrist

holds MD; can diagnose disorders and prescribe medication

Independent variable

variable purposefully manipulated by the researcher

Dependent variable

variable that is measured; depends on the IV

Experimental group

receives the treatment/manipulation

Control group

receives placebo; serves as baseline for comparison

Placebo effect

when participants show effects of treatment despite receiving no actual treatment

Double-blind study

neither participant nor experimenter knows group assignment; eliminates bias

Single-blind study

only the participant is unaware of group assignment

Operational definition

clear, precise, measurable definition of variables that allows replication

Confound

error or flaw in a study that threatens validity

Random assignment

randomly placing participants into control or experimental groups; reduces bias

Random sample

randomly selecting participants from a population; increases representativeness

Representative sample

sample that mirrors the general population in key characteristics

Positive correlation

both variables increase or decrease together

Negative correlation

as one variable increases the other decreases

Correlation does not equal causation

a relationship between variables does not prove one causes the other

Third variable problem

a separate variable may explain the relationship between two correlated variables

Illusory correlation

perceiving a relationship between variables that does not actually exist

Naturalistic observation

observing subjects in their natural environment; high real-world validity but no cause and effect

Case study

in-depth study of one individual; provides detailed info but cannot be generalized

Mean

arithmetic average; used in normal distributions

Median

middle value in a data set; used in skewed distributions

Mode

most frequently occurring value in a data set

Statistical significance

results are not due to chance; the manipulation caused the difference

Informed consent

participants must agree to take part in research before it begins

Debriefing

participants must be told the true purpose of a study after it concludes

Confidentiality

participants' identities must be kept secret

Neuron

basic cell of the nervous system

Dendrites

receive incoming signals from other neurons

Soma

cell body of the neuron; contains the nucleus

Axon

carries the action potential away from the cell body

Myelin sheath

fatty layer that speeds up the action potential and protects the axon; destroyed in MS

Terminal buttons

release neurotransmitters into the synapse

Synapse

gap between two neurons where neurotransmitters are released

Action potential

electrical charge that travels down the axon via movement of Na+ and K+ ions

All-or-none law

a neuron either fires completely or not at all; stimulus must exceed threshold

Refractory period

brief rest period after firing during which a neuron cannot fire again

Sensory (afferent) neurons

carry signals from the environment to the brain

Motor (efferent) neurons

carry signals from the brain to muscles and glands

Interneurons

located in the spinal cord; responsible for reflex arcs

Central nervous system (CNS)

brain and spinal cord

Peripheral nervous system (PNS)

all nerves outside the brain and spinal cord

Somatic nervous system

controls voluntary movement

Autonomic nervous system

controls involuntary functions (heart, lungs, digestion)

Sympathetic nervous system

arouses the body for fight or flight response

Parasympathetic nervous system

restores homeostasis after sympathetic activation (rest and digest)

GABA

major inhibitory neurotransmitter

Glutamate

major excitatory neurotransmitter

Dopamine

involved in reward and movement; excess linked to schizophrenia

Serotonin

involved in mood and emotion; low levels linked to depression

Acetylcholine (ACh)

involved in memory; destruction linked to Alzheimer's disease

Epinephrine and norepinephrine

involved in sympathetic nervous system arousal

Endorphins

natural pain-controlling neurotransmitters

Oxytocin

involved in love and social bonding

Agonist

drug that mimics a neurotransmitter

Antagonist

drug that blocks a neurotransmitter

Reuptake

unused neurotransmitters are reabsorbed by the sending neuron

SSRIs

block reuptake of serotonin; used to treat depression (e.g. Prozac, Zoloft)

Cerebellum

coordinates movement and balance; located in the hindbrain

Medulla

controls vital functions like heart rate and blood pressure; located in the hindbrain

Pons

bridge between brain regions; involved in basic functions

Reticular formation

controls alertness and arousal; located in the midbrain

Amygdala

processes emotions, especially fear

Hippocampus

critical for forming new memories

Hypothalamus

regulates hunger, thirst, body temperature, and sexual behavior; links to endocrine system

Thalamus

relay station for all senses except smell

Cerebral cortex

outer layer of the brain; responsible for higher-order thinking

Frontal lobe

decision making, planning, judgment, personality, and voluntary movement

Parietal lobe

processes sensory information (touch, pain, temperature)

Temporal lobe

processes hearing and face recognition

Occipital lobe

processes visual information

Somatosensory cortex

maps sensory receptors across the body; located in the parietal lobe

Motor cortex

maps motor responses across the body; located in the frontal lobe

Broca's area

left hemisphere; damage causes inability to produce speech (Broca = Broken speech)

Wernicke's area

left hemisphere; damage causes inability to comprehend speech

Corpus callosum

bundle of nerves connecting the two hemispheres; severed in split-brain patients

Split-brain research

Sperry and Gazzaniga; images shown to the left eye are processed in the right hemisphere and cannot be verbalized

Brain plasticity

the brain's ability to reorganize and heal itself after damage

Monozygotic (MZ) twins

identical twins; share 100% of DNA; used to study genetic influences

Dizygotic (DZ) twins

fraternal twins; share about 50% of DNA

Pituitary gland

master gland controlled by hypothalamus; releases growth hormones

Adrenal glands

release adrenaline (epinephrine) in response to stress; connected to sympathetic NS

EEG

measures brain activity but lacks spatial precision

CT/MRI

shows brain structures such as tumors; does not show activity

PET scan

uses glucose to show brain activity

fMRI

uses oxygen to show real-time brain activity; most detailed activity measure

Beta waves

brain waves associated with wakefulness and active thinking

Alpha waves

high amplitude waves associated with drowsiness