CDIS 421: Neuroscience of
Communication (Ch. 1-7) (Answered)
191 Questions And Correct Answers,
100% Correct, Latest 2024/2025.
What are the fundamental activities of a neuron?
Receiving input - from dendrites + soma, categorizing inputs into excitatory or inhibitory
Integrating input - axon hillock generates the overall change in baseline electrical state of neuron —>
determines if action potential can be created
Form an output - signal transmitted across axon to the synapse.
What are bipolar neurons?
one axon and one dendrite
- found in retinal ganglion cells
What are pseudounipolar neurons?
- One axon and one single primary dendrite that attach to the cell body at the same point
- Found in afferent system of spinal/trigeminal nerves.
What are multipolar neurons?
1 axon and several dendrites
Most abundant
Motor neurons and interneurons
What is the difference between neurons and glial cells?
neurons: generate and transmit nerve impulses; may be inhibitory or excitatory
glial cells: provide supportive functions to neurons
What are the two functional groups of glial cells?
microglia, macroglia
What are microglia?
"sanitation workers" of the brain, part of immune sytem, recruited to sites of injury or infection and
function as phagocytes to get rid of debris and dead tissue
What are the types of macroglia?
astrocytes, oligodendrocytes, schwann cells
What are similarities and differences between oligodendrocytes and Schwann cells?
,They both produce myelin for axons, but oligodenrocytes produce them for the CNS and Schwann
cells produce them for the PNS.
What are astrocytes?
The most numerous type of glial cells and are most complex
- They regulate K+ concentration and glutamate in extracellular space.
- They create the blood-brain barrier (BBB)
What is the blood-brain barrier?
a filtering mechanism of the capillaries that carry blood to the brain and spinal cord tissue, blocking
the passage of certain substances.
- astrocytes are directly involved in this!
What are electrical synapses?
Gap junction between 2 nerve cells that require extremely rapid signal transmission (retina, olfactory
bulb, cortex, etc).
- Pre-synaptic and postsynaptic membranes are extremely close to each other.
- Received ions flow trough gap junction channels
- Less vulnerable to fatigue
- Signal transmission is multi-directional
What are chemical synapses?
Synaptic cleft where impulses are slowly transmitted in one direction by neurotransmitters
- Neurotransmitters are received by chemical receptors on post-synaptic membrane
- Vulnerable to fatigue
- Most abundant in the nervous system
- Flexible and adaptive in structure and function
What are 3 types of ion channels?
voltage gated, ligand gated, mechanically gated
What are ligand gated channels?
Ligand binds to channel, causing a change in its shape, opening the channel
What are voltage gated channels?
channels that open and close in response to changes in membrane potential
What are mechanically gated channels?
open and close in response to physical deformation of receptors
What is neural integration?
the process by which incoming inhibitory and excitatory postsynaptic potentials summate at the
axon hillock and determine if the net change in electric potential of the neuron can cross the firing
threshold of the axon hillock.
What is the difference between gray and white matter?
, Gray matter - Lacks myelin; it contains mostly cell bodies of motor neurons and interneurons.
White matter - Large amounts of myelinated axons.
What is white matter called in the PNS vs. CNS?
PNS - nerves
CNS - bundles of axons (tracts, fibers, pathways, peduncles, fasciculi, leminscus, capsule, commissure
What are the functions of the spinal cord?
- It links the periphery of the body to the nervous system
- Transmits ascending + descending info between the periphery to the CNS.
- Responsible for reflexive activity.
What is the purpose of spinal cord segmentation?
Allows a specific body region to be registered to sensory/motor tracts at a specific zone of the spinal
cord.
What are the 3 broad regions of gray matter in the spinal cord?
ventral horn, dorsal horn, intermediate zone
Why does the amount of spinal gray matter vary?
Each segment of the spinal cord innervates different numbers of muscles, which each have different
afferent sensitivities to an area of the body.
What are the regions of white matter in the spinal cord?
dorsal column (posterior fasciulus)
lateral fasciculus
anterior fasciculus
What types of axons does the dorsal column of spinal white matter consist of?
Ascending axons/tracts, mediating sensory inputs related to thermal, discriminative touch, and
proprioception.
What types of axons does the lateral fasciculi of the spinal white matter consist of?
Both ascending and descending tracts
What types of axons does the anterior fasciculi of the spinal white matter consist of?
Both ascending and descending tracts.
What are the 3 segments of the brainstem?
midbrain, pons, medulla oblongata
What is a dermatome?
A specific area of the body that supplies sensory info to a specific dorsal root in the spinal cord.
What is a myotome?
Communication (Ch. 1-7) (Answered)
191 Questions And Correct Answers,
100% Correct, Latest 2024/2025.
What are the fundamental activities of a neuron?
Receiving input - from dendrites + soma, categorizing inputs into excitatory or inhibitory
Integrating input - axon hillock generates the overall change in baseline electrical state of neuron —>
determines if action potential can be created
Form an output - signal transmitted across axon to the synapse.
What are bipolar neurons?
one axon and one dendrite
- found in retinal ganglion cells
What are pseudounipolar neurons?
- One axon and one single primary dendrite that attach to the cell body at the same point
- Found in afferent system of spinal/trigeminal nerves.
What are multipolar neurons?
1 axon and several dendrites
Most abundant
Motor neurons and interneurons
What is the difference between neurons and glial cells?
neurons: generate and transmit nerve impulses; may be inhibitory or excitatory
glial cells: provide supportive functions to neurons
What are the two functional groups of glial cells?
microglia, macroglia
What are microglia?
"sanitation workers" of the brain, part of immune sytem, recruited to sites of injury or infection and
function as phagocytes to get rid of debris and dead tissue
What are the types of macroglia?
astrocytes, oligodendrocytes, schwann cells
What are similarities and differences between oligodendrocytes and Schwann cells?
,They both produce myelin for axons, but oligodenrocytes produce them for the CNS and Schwann
cells produce them for the PNS.
What are astrocytes?
The most numerous type of glial cells and are most complex
- They regulate K+ concentration and glutamate in extracellular space.
- They create the blood-brain barrier (BBB)
What is the blood-brain barrier?
a filtering mechanism of the capillaries that carry blood to the brain and spinal cord tissue, blocking
the passage of certain substances.
- astrocytes are directly involved in this!
What are electrical synapses?
Gap junction between 2 nerve cells that require extremely rapid signal transmission (retina, olfactory
bulb, cortex, etc).
- Pre-synaptic and postsynaptic membranes are extremely close to each other.
- Received ions flow trough gap junction channels
- Less vulnerable to fatigue
- Signal transmission is multi-directional
What are chemical synapses?
Synaptic cleft where impulses are slowly transmitted in one direction by neurotransmitters
- Neurotransmitters are received by chemical receptors on post-synaptic membrane
- Vulnerable to fatigue
- Most abundant in the nervous system
- Flexible and adaptive in structure and function
What are 3 types of ion channels?
voltage gated, ligand gated, mechanically gated
What are ligand gated channels?
Ligand binds to channel, causing a change in its shape, opening the channel
What are voltage gated channels?
channels that open and close in response to changes in membrane potential
What are mechanically gated channels?
open and close in response to physical deformation of receptors
What is neural integration?
the process by which incoming inhibitory and excitatory postsynaptic potentials summate at the
axon hillock and determine if the net change in electric potential of the neuron can cross the firing
threshold of the axon hillock.
What is the difference between gray and white matter?
, Gray matter - Lacks myelin; it contains mostly cell bodies of motor neurons and interneurons.
White matter - Large amounts of myelinated axons.
What is white matter called in the PNS vs. CNS?
PNS - nerves
CNS - bundles of axons (tracts, fibers, pathways, peduncles, fasciculi, leminscus, capsule, commissure
What are the functions of the spinal cord?
- It links the periphery of the body to the nervous system
- Transmits ascending + descending info between the periphery to the CNS.
- Responsible for reflexive activity.
What is the purpose of spinal cord segmentation?
Allows a specific body region to be registered to sensory/motor tracts at a specific zone of the spinal
cord.
What are the 3 broad regions of gray matter in the spinal cord?
ventral horn, dorsal horn, intermediate zone
Why does the amount of spinal gray matter vary?
Each segment of the spinal cord innervates different numbers of muscles, which each have different
afferent sensitivities to an area of the body.
What are the regions of white matter in the spinal cord?
dorsal column (posterior fasciulus)
lateral fasciculus
anterior fasciculus
What types of axons does the dorsal column of spinal white matter consist of?
Ascending axons/tracts, mediating sensory inputs related to thermal, discriminative touch, and
proprioception.
What types of axons does the lateral fasciculi of the spinal white matter consist of?
Both ascending and descending tracts
What types of axons does the anterior fasciculi of the spinal white matter consist of?
Both ascending and descending tracts.
What are the 3 segments of the brainstem?
midbrain, pons, medulla oblongata
What is a dermatome?
A specific area of the body that supplies sensory info to a specific dorsal root in the spinal cord.
What is a myotome?
