Unit 1: Biological Basis of Behavior

Based on 2024-25 CED

psychology

the scientific study of mental processes and behavior

psychodynamic perspective

focuses on the unconscious mind, early childhood experiences, and interpersonal relationships

behavioral perspective

focuses on learned behaviors, conditioning, & reinforcement

cognitive perspective

focuses on cognition, memory, thinking, & problem solving; eg. attention, perception, language, decision-making

biological perspective

focuses on the physical and biological (ie. brain structure, neurotransmitters, hormones, genetics) bases of behavior

sociocultural perspective

focuses on how culture (ie. norms, values, & beliefs) influences human behavior

evolutionary perspective

focuses on how the theory of evolution (ie. natural selection, adaptation, survival of the fittest) can explain psychological processes

humanistic perspective

focuses on motivation, self-actualization, and personal growth; this perspective is based on Maslow’s hierarchy of needs and unconditional positive regard

cognitive neuroscience

the study of brain activity linked with cognition

behavior genetics

the study of generic & environmental influences on behavior and their reach and limitations

Nature vs. Nurture

examines whether one’s genetics (nature) or environment and experiences (nurture) contributes more to the development of traits and behavior; the modern understanding is that it is the interaction of both genetics and environment (think epigenetics)

biopsychosocial approach

an integrated approach to psychology incorporating the biological, psychodynamic, and sociocultural perspectives

cognitive biases

systematic errors in thinking often leading to incorrect conclusions or irrational decisions

hindsight bias

the tendency to believe we would have foreseen an outcome after we have learned what the outcome is; eg. I knew we were going to win that game

overconfidence bias

having too much faith in your own knowledge, skill, etc.; in research, this can lead to rejection of results or bias toward findings due to “common sense”

confirmation bias

the tendency to reject any information that goes against our preexisting beliefs, skewing our perception of reality

percieving order in random events

finding order when there is none leading individuals to draw false conclusions

hypothesis

a testable prediction based on a theory that allows research to be conducted; should be falsifiable

falsifiable

able to be disprovent; allows for precise measurement and replication in experiements

operational definition

a precise, measurable definition of procedures or concepts in an experiment; these are carefully worded to make an experiment replicable

case study

a form of descriptive research that conducts an in-depth analysis of an individual or group; can be very revealing and suggest ideas for further study, however, atypical cases can be misleading and the small scope makes these ungereralizeable in the majority of scenarios

naturalistic observations

a form of descriptive research that studies the natural behavior of many individuals without manipulating the situation; can eggectively identify behaviors and tendencies, but doesn’t explain the behaviors

survey

a form of descriptive research that collects self reported attitudes and behaviors from a random sample of a population; can effectively reveal the tendencies of a larger population, but are subject to sampling bias and wording effects

sampling bias

generalizing results based on an unrepresentative sample

representative sample

a sample that fairly represents a population and its demographics, often by randomly selecting participants; each member of the population must have an equal chance of participating

wording effects

the ways in which the phrasing or wording of a question affects its responses; eg. gun safety laws vs. gun control laws

phrenology

the study of bumps on the skull; this “science” focused attention on localization of function

localization of function

The idea that certain functions are carried out in specific locations of the brain

dendrite

branching extensions from the cell body that receive neural impulses

axon

long extension from cell body that carries messages to other cells

cell body (soma)

part of a neuron that contains the nucleus

axon terminals

part of the neuron that forms synapses with other cells to send signals

myelin sheath

the fatty, insulating covering of parts of an axon that speeds up neural impulses

Nodes of Ranvier

spaces between the myelin sheath

synapse

junction between neurons that allows the brain to process complex information by connecting neurons

glial cells

support cells that maintain the necessary conditions for neurons to function properly

action potential

a neural impulse

resting potential

the polarization of a neuron that is not firing

depolarization

the reversing of an axon’s polarization during an action potential

repolarization

an axon’s return to its resting potential

threshold

the minimum amount of electrical energy needed to trigger an action potential

refractory period

the period during which repolarization occurs; an action potential cannot be generated during this period

excitatory nerve signal

nerve signals that trigger action potentials; these are more common

inhibitory nerve signal

nerve signals that slow/regulate action potentials

neurotransmitters

chemicals released into the synapse that allow neurons to communicate

reuptake

the process by which neurotransmitters are reabsorbed by the sending neuron; decreases the effect of mood-enhancing neurotransmitters

dopamine

excitatory neurotransmitter linked to movement, memory, learning, attention, & emotion

dopamine excess

linked to schizophrenia

dopamine deficit

linked to decreased mobility in Parkinson’s disease

serotonin

inhibitory neurotransmitter that regulates mood, hunger, sleep, & arousal

serotonin excess

Serotonin Syndrome

serotonin deficit

linked to depression

norepinephrine

excitatory neurotransmitter that triggers alertness & arousal

norepinephrine excess

associated with stress, anxiety, and mania

norepinephrine deficit

linked to depressed mood

glutamate

major excitatory neurotransmitter

glutamate excess

linked to migraines & seizures

GABA

major inhibitory neurotransmitter

GABA excess

linked to drowsiness, muscle weakness, & cognitive impairment

GABA deficit

linked to seizures, tremors, & insomnia

endorphins

inhibitory neurotransmitter known as rhe body’s “natural opiates;” regulates perception of pain & pleasure

Substance P

excitatory neurotransmitter that triggers pain & inflammation

Substance P excess

linked to inflammatory disorders

acetylcholine

excitatory neurotransmitter that controls muscle action and is linked to learning & memory

acetylcholine deficit

linked to Alzheimer’s Disease and Myasthenia Gravis

agonist

substances that increase or mimic the action of a neurotransmitter

antagonists

substances that decrease the action of a neurotransmitter by blocking or destroying receptor sites

Multiple Sclerosis

a condition in which the myelin sheath deteriorates, slowing or stopping action potentials

Myasthenia Gravis

a condition in which ACh receptors are blocked or destroyed stopping muscle contraction

psychoactive drug

a chemical substance that alters perceptions and moods

substance use disorder

continued substance craving and use despite significant life disruption and/or physical risk

depressants

psychoactive drugs rhat reduce neural activity & slow body functions

stimulants

psychoactive drugs rhat excite neural activity & speed up body functions; these often cause dilated pupils, increased heart rate, increased respiration, weight loss, and alertness

hallucinogen

psychoactive drugs that distort perceptions & evoke sensory images in the absence of sensory input

alcohol

depressant that causes slowed neural processing, memory disruption, REM disruption, & reduced self-awareness

barbituates

depressant that reduces anxiety and impairs memory & judgement; ex. benzodiazepines

opiates

depressants, known as narcotics that lessen pain & anxiety, and mimic endorphins; derived from the poppy plant; ex. morphine, heroin, oxycodone

nicotine

highly addictive stimulant found in tobacco; almost immediate effects

cocaine

powerful & addictive stimulant derived from the cocoa plant that temporarily increases alertness & euphoria; depletes the body’s supply of dopamine, serotonin, & norepinephrine; high is less than an hour

methamphetamine

powerful stimulant with a long lasting high; continued use reduces baseline dopamine

ecstacy (MDMA)

synthetic stimulant & hallucinogen that produces euphoria & social intimacy by releasing stored serotonin & blocking its reuptake; long term use damages serotonin-producing neurons and affects mood & cognition

LSD (acid)

hallucinogen that causes vivid sensory “trips” that are heavily influenced by the user’s mood and expectation; often causes euphoria but can also cause detachment and panic

marijuana (THC)

mild hallucinogen derived from the cannabis plant; amplifies sensitivity to sensation, relieves pain, time distortion, & relaxation; prolonged use impairs learning, memory, and increases risk of psychiatric disorders

physical dependence

changes in brain chemistry & physical symptoms of withdrawal

psychological dependence

psychological need for the substance ie. obsession with the substance, anxiety when the substance is inaccessible

near-death experience

altered state of consciousness after a close brush with death; similar to psychoactive drug experiences

Peripheral Nervous System

sensory & motor neurons; connect CNS to rest of body

Central Nervous System

brain & spinal cord

Autonomic Nervous System

controls glands & smooth and cardiac muscle; unconscious control

Somatic Nervous System

controls skeletal muscle & sensory & motor sensation; conscious control

Sympathetic Nervous System

responsible for arousal and the “fight or flight” response; the faster branch of the autonomic nervous system; slows digestion and cools the body

Parasympathetic Nervous System

responsible for calming the body and the “rest and digest” response; the slower branch of the autonomic nervous system

motor neurons

carry information from the CNS to the PNS

sensory neurons

carry information from the PNS to the CNS

interneurons

communicate and process information within the CNS

reflex

a simple, automatic response to a specific sensory stimulus; does not involve the brain, only the spinal cord

nervous system

the body’s fast, electrochemical communication system

endocrine system

the body’s slow, chemical communication system; hormones secreted from glands into the bloodstream to affect tissues

adrenal glands

secrete adrenaline, epinephrine, & norepinephrine to arouse the body in times of stress; located above the kidneys

pituitary gland

most influential gland of the endocrine system; located in the brain; controlled by the hypothalamus; regulates growth and controls glands