Franz Gall
created pseudoscience of phrenology
corpus callosum
thick band of tissue connecting brain hemispheres, made of axons
phrenology
mapping out personality by head (noggin) features
neurons
nervous system cells that send messages (communicate electrically but chemically between each other)
sensory neurons
register stimulation through 5 senses
interneurons
interpret info, transfer to motor
motor neurons
movement in response
cell body
holds nucleus, controls neurons
axon
tail-like structure covered in myelin sheath (fatty, protects neurons) transfers action potential from cell body to axon terminal
vesicles
at the end of axon, pouch like structures that contain neurotransmitters
neurotransmitters
chemical messages released from one neuron and absorbed by others and translate into specific behaviors, 250 in the human body
acetylcholine
must be released for muscle contraction, learning/memory
dopamine
fine tuned motor functions, focus/concentration, learning/pleasure (low levels ADHD, high levels schizophrenia)
serotonin
everyday wellbeing (mood), sleep and appetite (low levels depression)
endorphins
painkiller, evolutionary adaptation (painkilling drugs mimic endorphins)
substance P
pain, tells your body to stop something
norepinephrine
alertness, arousal (low levels depressive episodes)
gaba
inhibitory, blocks other neurotransmitters (low levels seizures, tremors, insomnia)
glutamate
exitory, leads to others being released (high levels migraines, seizures)
agonists
increase/mimic effects of a neurotransmitter (ex: stimulants)
antagonists
decreases/blocks effects of neurotransmitters (ex: alcohol, ecstasy)
reuptake
recycling process for neurotransmitters, certain meds block reuptake (ex: Adderall blocks reuptake of dopamine)
neuralplasticity
ability for increased efficiency after practice on a cellular level (dendrites grow closer to axon terminals for ease)
somatic nervous system
skeletal/involuntary, consciously manipulates your body
autonomic nervous system
involuntary, things you can’t control
sympathetic nervous system
part of autonomic system, arousal (ex: pupil dilation, increased heart rate, fight/flight)
parasympathetic nervous system
soothes you (ex: breathing and heart slows, prepares for sleep)
endocrine system
glands releasing hormones
pituitary gland
growth hormones, working during sleep and controlling other glands
thyroid glands
control metabolism
parathyroid glands
regulates calcium
adrenal glands
fight/flight, sympathetic activation
pancreas
regulates blood sugar with insulin
ovaries
releases egg monthly, releases estrogen
lesion
tissue destruction
EEG
measures electrical activity in the brain (action potentials)
PET scan
measures temperature of different areas of the brain indicating the warmer (more active) and colder (less active)
MRI
soft tissue scan
FMRI
works like an MRI and a PET scan
brain stem
medula, tells heart to beat, lungs to breathe, etc.
pons
coordinates movements, alertness/arousal
reticular formation
bundle of nerves running through brain stem and pons, scans sensory info to see if stimulus is important
thalamus
“traffic director” of sensory messages to proper brain area
cerebellum
coordinates motor function, insulates brain stem, muscle memory
hypothalamus
in charge of the endocrine system (metabolism, homeostasis, basic emotions)
limbic system
middle brain/memories and emotions
hippocampus
short term memory, 7 ± 2 pieces of info can be in short term, assembles long term memory
amygdela
assesses stimuli to determine if it’s a threat and if so triggers fear/aggression
cerebral cortex
takes up 1/3 of our brain, 2/3 of neurons in cortex
glial cells
support cells for neurons
occipital lobe
back of brain, visual processing
parietal lobe
sensory cortex
temporal lobe
auditory processing
frontal lobe
motor function (left and right motor cortexes), cognitive abilities
free association areas
within frontal and temporal lobes, no role in motor/sensory function, just cognitive