W1.1 - Intro to Neuroscience

what is embodied cognition

our experience of being a person in the world is built on our sensory and motor experiences

what is the basic purpose of neurons?

to integrate and relay information from neurons in a neural circuit

most synapses are (chemical/electrical)

chemical

where can axons synapse?

cell bodies and dendrites

how many neurons are there in the human brain

86 billion

what is convergence

the number of inputs to a single neuron

what is divergence

the number of targets of a single neuron

how to neurons communicate?

via secretion of neurotransmitters

how do neurotransmitters modify electrical properties of the target cell?

by binding to receptors

projection neurons extend to (local/distant) neurons while interneurons extend to (local/distant) neurons

distant, local

what is the role of glial cells?

important for repair and support of neurons

true or false: glial cells do not produce their own signals

true

are there more neurons or glial cells?

glial cells

what are the 7 main glial cell functions?

maintain ionic environment; modulate nerve signal rate; control uptake/metabolism of neurotransmitters; scaffolding; aid recovery; interface brain and immune system; facilitate convective flow of interstitial fluid

what are the 3 types of glial cells

astrocytes, oligodendrocytes, microglial cells

where are astrocytes located

only in the CNS

what is a key function of astrocytes

maintaining chemical environment for neuronal signaling and forming the BBB

what cell works overtime during a TBI to try to keep things functional

astrocytes

________ lay myelin down for the CNS while ________ lay myelin down for the PNS

oligodendrocytes, schwann cells

oligodendrocytes can serve _____ neuron at a time, and damage causes _____ effects

>1, diffuse

schwann cells can serve _______ neuron at a time, and damage causes ______ effects

1, local

oligodendrocytes and schwann cells are subtypes of what cell?

glial cells

where are microglial cells derived from

hematopoietic precursor cells

microglial cells are similar to what immune cell?

macrophages

what are the 2 types of neural stem cells in the adult brain

subset of astrocytes and oligodendrocyte precursor cells

where can you find subsets of astrocytes?

near the ventricles

where can you find oligodendrocyte precursor cells?

throughout the white matter

interneurons only participate in ___ aspects of circuitry

local

what is the difference between extracellular recording and intracellular recording?

extracellular is near the cell of interest, intracellular is inside the cell of interest

extracellular recording is useful for detecting __________ while intracellular recording is useful for detecting _______

temporal patterns, smaller graded changes

in the knee-jerk reflex, the afferent neurons are ________ neurons

sensory

neurons at rest generate a (positive/negative) resting membrane potential

negative

when talking about electrical charge of a neuron, we are always referencing the _______ charge

inside

what 3 things need to be in place to have an electrirc potential?

difference in ion concentration; selectively permeable membranes; concentration gradient maintained by active transport

why do we have equilibrium with a concentration gradient?

because the electric potential opposes it and holds it steady

action potentials are (self/non-self) regenerating spikes of electrical activity

self

how do we convey information along a neuron?

via an action potential

how is the intensity of a stimulus conveyed in an action potential

in the speed of the AP

a bigger stimulus will result in (slower/faster) action potentials

faster

what is the typical resting potential of a neuron

-65mV

what is the typical threshold of a neuron

-50mV

hyperpolarization brings the neuron (closer to/further from) an action potential, while depolarization brings the neuron (closer to/further from) an action potential

further from, closer to

what are the 3 types of neuronal electrical signals?

receptor, synaptic, and action potentials

how are receptor potentials different from action potentials?

amplitudes are graded in proportion to the magnitude of the stimulus

how are synaptic potentials different than action potentials?

the amplitudes vary according to number, strength, and previous amount of synaptic activity

at rest, the cell is more permeable to _______ and relatively impermeable to ________

potassium, sodium