The Brain and the Nervous System Flashcards
dendrites
the little feelers that receive information
axon
carries output to other neurons
axon terminals
the end of the axon that actually puts the info into the synapse
synapse
the junction between two nerve cells, which is a minute gap through which information
excitatory synapses
make the postsynaptic neurons more likely to fire
inhibitory synapes
make the postsynaptic neurons less likely to fire
base line for neuron fire
-55mV
A neuron in resting state
is polarized
negative on the inside, positive on the outside (difference of -70mV)
Action Potential
the movement of the positive from the outside to the inside creates energy which allows the neuron to fire
White matter
myelinated, created for long distance communication, the highways of the brain.
grey matter
un-myelinated, short distance communication, the neighbors of the brain
the average human has _____ neurons in their brain
30-100 billion
the average human has _____ synapses in their brain
500 trillion
Acetylcholine
motor control over muscles
norepinephrine
arousal, fight or flight response, attention
serotonin
emotional states and impulsiveness, dreaming
dopamine
reward and motivation, motor control over voluntary movement
GABA
inhibition of action potentials, anxiety reduction
glutamate
enhancement of action potentials, learning and memory
endorphins
pain reduction, reward
transcranial magnetic stimulation
scientists can use TMS to study the effects of temporary brain damage, it disrupts brain activity by activating all neurons at once with a magnet
electroencephalography
shows the electrical activity of large populations of neurons with high temporal precisions
PET and fMRI
reveals which brain locations are particularly active at any moment in time by recording where blood flow is in the brain
spinal cord
coordination of reflexes; carries sensory information to the brain and motor signals away from the brain
brain stem
an extension of the spinal cord
controls functions associated with survival such as heart rate, breathing, and swallowing
cerebellum
essential for coordinated movement and balance
limb coordination
compensation of eye position for head movement
thalamus
the sensory gateway to the brain
receives almost all incoming sensory info before that information reaches the cortex
hypothalamus
regulation of bodily function
- fighting
- fleeing
- feeding
- fornification
hippocampus
the formation of memories and mental maps
amygdala
emotional responses and processing emotional information
basal ganglia
planning and production of movement
also learning to associate actions with consequences
cerebral cortes
the outer layer of gray matter
occipital lobe
vision
primary visual cortex
temporal lobe
hearing, memory
primary auditory cortex
frontal lobe
thought, planning, movement, actions, both abstract and simple
thinking and action become more abstract as you move further and further forward in your frontal lobe
prefrontal cortex
abstract action
primary motor cortex
concrete action
parietal lobe
touch, spatial relations, attention to the environment
primary somatosensory cortex
basic sensation
corpus callosum
a massive bridge of millions of axons that connects the hemispheres
right hemisphere
better with spatial realtionships
left hemisphere
better with language
3 principles of evolution by natural selection
- traits vary between individuals in a population
- some individuals in a population survive and reproduce at a higher rate than others because of specific traits
- traits get passed on to offspring
