psychology unit 1

Heredity

predisposed characteristics that influence an individual’s physical, behavioral, and mental traits and processes

Environment

external factors that an individual experiences, such as a person’s family, friend, groups, school, society cares about

Evolution

focuses on natural selection, the passing down of genes, and how many of our behaviors and mental processes actually come from our ancestors

Eugenics

improving the genetic quality of humans by promoting reproduction of individuals with desirable traits and discoursing reproduction between those with undesirable traits.

Henry Geddard

American eugenicist, pushed to use intelligence tests to rank people into different mental categories → society should prevent feeble minded people from having children

Heritability

Mathematical measure to estimate the variation there is in a population related to its genes, nature & nurture!
EX: 0.7 = 70% genetics and 30% environment

Epigenetics

examines how the environment and a person’s behaviors affect someone’s genes and how they work →how body reads DNA sequence, happens slowly, genes are being turned on or off

Plasticity

When the brain changes and builds new neural pathways in response to a person’s experiences

Central Nervous System (CNS)

brain and spinal cord

brain: processing sensory information → controlling motor functions, thinking, emotions, regulating bodily functions

spine: connects brain to the rest of the body

Peripheral Nervous system (PNS)

different nerves that branch off from the brain and spine, a communication network that connects the CNS to the rest of the body, sending information to the brain and carrying commands back, controls movements

Afferent Neurons (sensory neurons) PNS

send signals from sensory receptors (nerve endings) to the central nervous system, TO BRAIN AND SPINAL CORD, approaches brain to stimulate you (feelings, pain, etc)

Efferent Neurons (motor neurons) PNS

send signals from the central nervous system to the peripheral nervous system, FROM BRAIN AND SPINAL CORD, exits brain so you can initiate action

PNS: Somatic Nervous System (skeletal)

includes skeletal muscle movements and 5 senses, conscious and voluntary movements, brain sending signals to muscle to move

PNS: Autonomic Nervous System

controls involuntary activities, makes sure you breathe, heart is beating, stomach is digesting, bodily functions you need to survive → homeostasis, provding stability

ANS: Sympathetic Division

fight or flight response
what gets your body mobilized and ready for action, making your heart beat, faster, eyes dilate, and increases your breathing

slows down digestion so energy can go where it’s needed

ANS: Parasympathetic Division

rest and digest
Slows your heart rate, increases digestion, and helps you focus on saving and storing energy

Neurons

basic functional unit of the nervous system

communicates by using electrical impulses and chemical signals to send information throughout the body

Cell

Soma: where the nucleus is! → contains genetic material that allows neurons to function
Dendrites: receive chemical information from adjacent neurons through its receptor sites to another neuron down the axon fiber

Axon Fiber: carries a signal away from the soma and out through the neurons terminal branches → transmits signals (protected by glial cell/schwann cell)

Schwann Cell

around axon fiber

produces myelin sheath that covers axon and protects it from being damaged
increases how fast action potential can travel down the axon

Myelin Sheath

protects axon
there are gaps in it that are known as NODES OF RANVIER → continuing action potential into AXON TERMINAL (endpoint)

where neurotransmitters are released into synaptic gap and cent to receiving neuron

nociceptors

pain receptors in skin
Afferent neurons send pain signals to the spinal cord into interneurons connecting sensory neurons to motor neurons (afferent and efferent), which causes muscles to move due to pain → reflex arc

Interneurons

neurons within brain and spinal cord
communicate internally and connect the sensory neurons to motor neurons, also known as efferent neurons

Glial Cells

all over the brain!

insulate neurons to speed up transmission and facilitate communication

neural transmission

all or nothing principle!!!

a neuron will only fire if the threshold is met
minimum amount of stimulation required for a neuron to fire and send an action potential → starts with DEPOLARIZATION

Depolarization

positive sodium ions flow into the neuron making the inside of the cell more positive allowing electrical charge to move along the axon into next neuron

Refractory Period

after neuron fires signal

brief period where neuron can’t fire again because it has to recharge and return to its resting state where it has a stable negative internal charge

Axon Terminal

where the signal is converted and sent to another neuron through a small pocket of space between the axon terminal of one neuron and the dendrite of another
tiny space: synapse

Chemical Synapses

uses neurotransmitters, chemical messengers that sends messages through the nervous system

Electrical Synapses

messages that need to be sent quickly and immediately

Synaptic Space

neurotransmitters diffuse through synaptic gap to deliver their messages

narrow space between two neurons
presynaptic terminal of one neuron and the postsynaptic terminal of another

Presynaptic Terminal (axon terminal of the neuron)

converts electrical signal to a chemical one and then sends neurotransmitters into synaptic gap

Postsynaptic Terminal

when neurotransmitters are accepted in the dendrite of the receiving neuron

through this process, they unbind with the receptors, some destroyed some reabsorbed

Reuptake

the transmitters are left in the synaptic gap are taken back and REABSORBED

Excitatory Neurotransmitters

when neurotransmitters bind to receptors it gets excited sometimes

increase likelihood that a neuron will fire an action potential

Inhibitory Neurotransmitter

Will decrease likelihood that a neuron will fire action potential

Hyperpolarization

when inside of neuron becomes more negative. moving neuron farther away from its threshold or intensity level needed for action potential

Multiple Sclerosis

when myelin sheath (protection) is damaged, resulting in the disruption of the transmission of electrical signals
- muscle weakness
- coordination problems
- fatigue

Myasthenia Gravis

autoimmune disorder that affects the communication between nerves and muscle
antibodies block or destroy acetylcholine receptors (enables bodily function things) preventing muscle contraction and causing muscle weakness and fatigue

Endocrine System

slower moving compared to nervous system
helps regulate different biological processes in body

Adrenaline

Epinephrine helps with the body’s response to high emotional situations and helps form memories
expands our air passages in the lungs and redistributes blood flow
fight or flight response

Leptin

balance our energy by supressing hunger
signals that the brain has stored enough fat, reducing someone’s appetite

Ghrelin

hunger hormone

signals to brain that we are hungry

helps promotes growth hormones

Melatonin

produced by the pineal gland in the brain and helps regulate sleep-wake cycles, circadian rhythm
Helps promote sleep and is typically more prevalent in the evening

Oxytocin

produced in the hypothalamus and released by the pituitary gland
love hormone → promotes feelings of affection and emotional bonding

Psychoactive Drugs

substances that purposefully alter an individuals perception, consciousness, or mood, these drugs can broken down into different categories!

Stimulants

excite and promote neural activity
give individuals energy, reduce a person’s appetite, and cause them to become irritable

Depressants

drugs that reduce neutral activity in an individual, these drugs case drowsiness, muscle relaxation, lowered breathing, and death if overdose

Hallucinogens

marihuana, peyote, and LSD
cause individuals to sense things that aren’t actually there

reduce individuals motivation and lead them to panic

Opioids

depressant! but have their own category due to addictive nature
give an individual pain relief
DRUGS INFLUENCE TRANSMITTERS INSIDE BODY

Agonist Drug

increases effectiveness of neurotransmitters by mimicking it and enhancing their effects or boosts production of transmitter itself

Can block the reuptake process, leading to an increase in neurotransmitter levels in the synapse since the excess isn’t reabsorbed

Ex: anti-anxiety medication

Antagonist Drug

decreases the effectiveness of a neurotransmitter
block them from being released from the presynaptic axon terminal or block the intended neurotransmitter from binding
Ex: medication for schizophrenia that blocks dopamine receptors
alcohol: blocks the release of glutamate, which acts as a depressent

Brain Plasticity

ability to change and adapt even after its injured, rewires itself and forms new neural connection or strengthen existing ones

helps learn new skills, recover from damage, or adjust to new experiences,

brain stem

medulla oblongata, pawns, midbrain
connects the brain to spinal cord which transmits messages between brain and body

medulla

located just above the spinal cord and below the pond

controls autonomic functions such as heart rate, blood pressure, breathing, and digestion, things we don’t think about!

the pons

on top of the brain stem

connects different parts of nervous system: cerebrum and cerebellum
important role in sleep and dreaming, regulating REM

Cerebellum (little brain)

located at the base of the brain in the back, controls muscle movement, balance, and some forms of procedural learning

Damage can lead to uncoordinated or clumsy movement

procedural learning

long-term memory that involves learning how to perform tasks or actions through repetition and practice often without conscious awareness

Reticular Activating System

bundle of nerves that run through the brainstem, neurons that extend from brain stem up to the hypothalamus and other areas of the brain, filters incoming sensory information and alerts to important signals

regulates arousal and consciousness
controls sleep-wake cycle and general alertness

Brain’s Reward Center

neurotransmitters, dopamine to create that feeling, reinforces behaviors and mental processes

makes an individual feel satisfaction and pleasure

limbic system

between brain stem and cerebral cortex
includes thalamus, hypothalamus, hippocampus, and amygdala
emotion, memory, learning, and motivation

thalamus: limbic system

what receives sensory information, except for smell, and sends that information to the right areas of the brain

Ex: if you hear a sound, information → auditory cortex to be interpreted

Hypothalamus: limbic system

helps maintain homeostasis
controls hunger, thirst, body’s temperature, sexual behavior

regulates endocrine system by signaling the pituitary gland

Pituitary Gland

releases hormones that affect growth, our metabolism, and other glands throughout the body

Hippocampus: limbic system

key role in forming long-term memories, not storing

Amygdala: limbic system

involved in emotion, especially fear and aggression

helps you respond in emotional situations and form emotional memories

Cerebral Cortex

outer layer of the brain

left and right hemispheres → connected by the corpus callosum, thick band of neural fibers that allows communication

frontal, parietal, temporal, occipital lobes → higher order thinking, sensory processing, decision making, voluntary movement

Occipital Lobes

back of the brain
process visual information; everything you see is interpreted here

Temporal Lobe

forward in brain, just above ears
process sounds and help with language comprehension, understand words

TEMPORAL LOBE: Wernicke’s area

responsible for language and comprehension

if damaged, not able to produce meaningful speech

Parietal Lobes

regions that help your brain organize and make sense of information
information from different senses is brought together which allows you to make sense of the world in a more complete way

Parietal Lobes: Somatosensory Cortex

processes touch, pressure, pain, and temperature from the body
better understanding of where your body is in space
interprets what you’re touching