the brain

evolutionary perspective

human behavior, emotions are shaped by natural selection to enhance survival and reproduction

natural selection

• things that lead to an organism

• increase survival and reproduction

• will be what is passed to next gen

heredity

• passing on of physical/mental characteristics genetically from one gen to another

nurture

biological inheritances

• influence on physical, behavioral, mental traits

nurture

• external factors

• family interactions + education + environment

eugenics

used genetics and evolutionary perspective to discriminate others

twin studies/family/adtoption

• 50% - 70% intelligence genetic

• 25% - 50% variation in personality is in genetics

• 25% - 50% genetic nature

• 50% - 75% environmental

neural networks

• networks of nerve cells that integrate sensory input and motor output

• 100 billion neurons

nerves

bundle of neurons that form a cable

nervous system

body’s electrochemical communication system/circut

• pulling info together

• thousands of connected nerve cells communicating throughout the brain

central nervous system

• brain, spine in center

brain

billions of neurons organized in neural networks to connect the brains diff regions

• controls everything in body by neural networks

spinal cord

• connects peripheral nervous system to brain

• carries messages between brain and body

reflex arc

one sensory, interneuron, and motor neurons is involved

peripheral nervous system

nerves that connect brain + spinal cord to rest of body

somatic nervous system

controls muscles/voluntary movements

sensory neurons/afferent nerves

carry messages to brain

motor neurons/efferent nerves

tells muscles + glands what to do

autonomic nervous system

messages to/from internal organs, monitoring processes like breathing, heart rate, digestion

sympathetic nervous system

arouses body to mobilize action

• fight/flight response

parasympathetic nervous system

calms the body

neuron

one of two types of cells in nervous system

glial cells (glia)

provides structure, insulation, communication, and waste transportation

• keeps neurons running smoothly

• aids in homeostasis

cell body

• nucleus, directs manufacture of substances that neuron needs for growth + maintenance

dendrites

treelike fibers projecting from a neuron, which receives into that moves it to the neurons cell body

axon

part of neutron that takes info away from the cell body to other cells

myelin sheath

layer of fat cells that encases most axons

• speed up transmission of nerve impulses

resting potential

inactive neuron, voltage between inside + outside axon wall

threshold

once impulse reaches certain level of intensity, “fires”

action potential

wave of positive electrical charge that goes down the axon

all or nothing principle

happens completely or not at all, moves all the way down axon without losing intensity

depolarization

shifts electrical charge distribution so the cel is less negatively charged compared to environment

refractory period

recovery time that neuron needs between action potentials

• during ts period, neurontransmitters can be fired

synapse (synaptic gap/space)

tiny spaces between neurons and gap between neurons that synapses create

synaptic vesicles

stored chemicals called neurotransmitters

neurotransmitters

chemical substances stored in tiny sacs

receptor site

received chemical signals from neurotransmitters

reuptake

neurotransmitter is absorber by sending neuron

excitatory neurotransmitters

move neuron closer to firing

inhibitory neurotransmitter

making it fire less likely

dopamine

motivation + reward

• tiktok

serotonin

sleep mood emotions

• depression

norepinephrine

excites heart rate, sleep, controls alertness

• also linked to depression

glutamate

excitatory neurotransmitter

• involved w memory

• too much overstimulates brain - can lead to migraines

GABA (gamma-aminobutyric acid)

inhibitory neurotransmitters

• valium increases levels to decrease anxiety bc it inhibits neurons from firing

endorphins

shields body from pain, increases feelings of pleasure

substance P

pain, immune response

• oversupply can lead to chronic pain

• P IS FOR PAIN

acetylcholine

learning, memory, muscle action

• curable - inhibits acetylcholine so you can’t move

• botox

agonist

excited by mimicking neurotransmitters or blocks reuptake

antagonist

inhibits particular neurotransmitters release or blocks its effect

reuptake inhibitors

drugs that prevent neurotransmitters from reabsorbing by presynaptic axons

multiple sclerosis

chronic disease affecting nerve system where immune system attacks protected sheath that covers nerve fibers

• causes communication problems between brain + body

myasthenia gravis

chronic autoimmune disease affected neuromuscular junction (neuron activates muscle to contract) and produces weakness of muscles

pitutitary gland

pea sized gland beneath the hippocampus

master gland

controls growth and regulates master gland

hormones

chemical messengers produced by glands that regulate various bodily functions.

adrenaline

stress hormone, epinephrine

produced by adrenal glands

released in bloodstream

fight/flight response

leptin

signals hypothalamus that body has enuff fat stored to function normally

leptin levels are high enuff, appetite is inhibited

ghrelin

produced by stomach, stimulates hunger

hunger hormone, increases food intake, and promotes fat storage

melatonin

hormone, regulates sleep/wake cycles

oxytocin

hormone produced by hypothalamus released by pituitary

mothers bonding with children after birth

stimulants

physcoactive drugs that speed up ur body

caffeine

coffee in da morning

worlds most wideley used drug

withdrawls: headaches, apathy, lethargy, and concentration difficulties

cocaine

euphoric feeling for 15-20 min

rush depletes brains supply of dopamine/serotonin/norepinephrine after so ur depressed

deppressants

drugs that slow down mental and physical activities 

alchohol, barbituates, tranquillizers

alcohol

slows down brain activity, reaction time, judgement

loosen up after a few drinks, reduced motor skills

effects: body weight, amount consumed, metabolized alcohol, tolerance, women affected moar

barbiturate

sleep aid

decreases central nervous system activity

hallucinogens

pyshcoactive drugs, causes distortions

weed/pot, acids

marijuana

cannabis, distorted

spontaenous ideas, sensitivity to senses

impair attention/memory

LSD: pleasurable or disturbing perceptions

opioids

narcotics, pain killers

very addictive, depressed nervous system

neurotransmitters - endorphins

amphetamines

boosts energy, stay awake lose weight

increases super focus

adderal, college 

withdrawl syndome

discomfort/stress that follows discontinuing of a drug

plasticity

brain somewhat plastic/flexible

ability to rewire damaged part of brain

EEG

ELECTRICAL activity

records brain waves and sends signals to computer 

CAT/CT

special brain x ray

info collected by computer to reveal strokes, tumors, or injuries

PET scan

based on metabolic changes in brain related activity

MRI

magnetic field around body + using radio waves to make photos of persons brain tissue + chemicals

fMRI

detects activity and brain function, shows blood flow as well

hindbrain

lowest portion of the brain

controls basics to keep us alive

cerebellum

“little brain”

muscle movements, coordination

medulla

where spinal cord enters skull

basic life functions, cant live without it

breathing and heart rate

pons

bridge connecting cerebellum and brain stem

in hindbrain

sleep and dream

brain stem

stem in the brain area

includes much of the midbrain + hindbrain

controls breathing and heart rate

midbrain

located between the hindbrain and the forebrain

retiuclar formation

REWARD CENTER

alertness, sleep/wake cycles,

forebrain

brains largest divison + forward part

cerebral cortex

outer layer responsible for mental functions

thalamus

sends brain messages to where they need to be

hypothalamus

controls hunger and thirst

limbic system

associated with memory and emotion

amygdala

alomond shaped structure inside brain

control fear

hippocampus

storage of memories

corpus callosum

band of nerve fibers that join two parts of the brain together (left and right)

somatosensory cortex

touch and body sensations

motor cortex

voluntory movements

prefrontal cortex

frontal lobe: responsible for decision making, reasoning, and personaility

brain lesioning

expierementally destroy brain to study behavior after removal

aphasia

impairment of langauge

brocas area

left hemisphere damage

impair speaking

kinda like alzheimers

wernicke area

impair understanding

i say words but dont mean any of them

split brain research

my brain is split and i cant communicate between 2 sides

CAT MAZE BLINDFOLD ABUSE STOP