ch3 Flashcards
neuroanatomy
study of parts and functions of neurons
neurons
individual nerve cells that make up the nervous system
dendrites
root like parts of the cell that grows out the body. makes synaptic connections with other neurons.
cell body/soma
contains the nucleus and other vital parts of the cell
axon
wire like structure that stretches from the cell body and leads to the terminal buttons
myelin sheath
fat that covers the axon of the neurons
terminal buttons
branched ends of axon that contains neurotransmitters
neurotransmitters
chemicals in terminal buttons that allow neurons to communicate. fits into receptor cites (dendrites)
synapse
space between terminal buttons of neuron a and dendrites of neuron b
threshold
(in ch3) minimum amount needed for a neuron to fire
action potential
when a neuron sends info (electric potential charges) down the axon.
all or nothing principle
states that a neuron either fires or it doesn’t. no in between
inhibitory neurotransmitters
prevents neurons from firing
excitatory neurotransmitters
encourages cells to fire
nervous system
made up of 2 sets of neurons (since neurons can only fire 1 direction)
one set fires towards the brain, the other fires from the brain towards the body
afferent/sensory neurons
takes info from nerves to brain
interneurons
takes info once it reaches the brain/spine and directs it to other parts of the brain or efferent neurons
efferent neurons
takes info from the brain to the rest of the body
central nervous system (CNS)
consists of the brain and spinal cord. located in the skull and vertebrae
peripheral nervous system (PNS)
all other nerves not encased in bone (divided into somatic and autonomic nervous system
somatic nervous system
controls voluntary muscle movements
autonomic nervous system
controls autonomic functions (heart lungs, internal organs). and is divided into the sympathetic and parasympathetic nervous systems
sympathetic nervous systems
controls the body;s response to stress (flight or flight). slows down other functions (like digestion) to conserve energy
parasympathetic nervous system
slows down sympathetic nervous system after sttress
reflexes
reactions that are not being controlled by the brain
accidents
method of studying the brain. major accidents that damage the brain and cause certain behaviors can be cross-referenced to pre-accident behaviors
lesions/lesioning
removal/destruction of the brain (lobotomies)
electroencephalogram (EEG)
machine that detects brain waves (and how it changes)
computerized axial tomography (CAT/CT scan)
uses x-ray cameras to take a 3d picture of the brain and turns it into a detailed 3d image.
magnetic resonance imaging (MRI)
gives a detailed 3d image using magnetic fields
positron emission tomography (PET scan)
measures how much of a chemical a part of the brain is using
(used to see what parts of the brain are most active during certain tasks.)
functional MRI (fMRI)
combines MRI (magnetic fields) and PET (chemical detection) scans
can show brain structure & blood flow during certain tasks
hindbrain
located at top of spinal cord & controls basic biological functions. contains medulla, pons, and cerebellum
medulla
controls blood pressure, heart rate & breathing.
pons
located above medulla, connects hindbrain with midbrain and forebrain and is used when making facial expressions
midbrain
above spinal cord but below forebrain. coordinates muscle movements & sensory info.
reticular formation
net-like connection of cells in the midbrain. controls arousal & ability to focus.
if this does not function, then you will fall into a coma
forebrain
largest part of the brain. Controls thought & reason. contains the thalamus. hypothalamus. amygdala, and hippocampus
thalamus
located on top of brain step. receives sensory signals & sends them to other part of the forebrain
hypothalamus
located next to thalamus. responsible for metabolic functions (hunger, thirst, body temp, libido, endocrine system)
amygdala & hippocampus
hippocampuses are the arms surrounding the thalamus, and the amygdala are located at the ends of each arm.
The hippocampus is important for memory (it redirects memories to parts of the cerebral cortex), and amygdala is important for experiencing emotion.
cerebral cortex
wrinkled surface of the brain. is 1 mm of densely packed neurons that gradually connect with each other as you grow.
has 8 different lobes (4 in each hemisphere)
(frontal lobe, parietal love, temporal lobe, occipital lobe)
hemispheres
cerebral cortexes are divided into left & right hemispheres
left hemisphere
gets sensory info and controls the right half of the body
right hemispheres
gets sensory info and controls the left half of the body
brain lateralization/hemisphere specialization
for there to be specializations in function in different hemispheres
frontal lobe (location + function)
located behind the eyes, and plays a major role in memory, abstract thought, and directing the thought process
motor cortex (location + function)
vertical strip behind the frontal lobe. controls voluntary movement.
the top of the body is controlled by the bottom of the cortex and vice versa
parietal lobes (location + function)
located behind frontal lobes. contains sensory cortex/somatosensory cortex.
sensory/somatosensory cortex (location + function)
vertical strip behind the motor cortex. receives incoming touch sensations from the body.
the top of the cortex receives info from bottom of the body, and vice versa.
occipital lobes (location + function)
located at back of brain. processes messages from eyes (retinas). the left half of the retina is processed in the left occipital lobe, and vice versa.
temporal lobe
processes sound sensed by the ears. ears turn sound into neural impulses, where they are interpreted by the auditory cotices.
wernicke’s area
processes written & spoken speech
brain plasticity
brain is slightly elastic. parts of the brain can adapt to perform other functions if parts of the brain are damaged. The younger a person is, the more likely this is to happen.
endocrine system
system of glands that secrete hormones that affect some biological processes.
controlled by hypothalamus
adrenal glands (autonomic nervous system)
produces adrenaline, which triggers fight or flight.
ovaries/testes
produces sex hormones
