Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy > CNS Tissue Ch. 12 > Flashcards

CNS Tissue Ch. 12 Flashcards

1
Q

What are the two divisions of the nervous system?

A
  1. CNS (Central Nervous System) which contains A. The Spinal Cord, and B. The Brain
  2. PNS (Peripheral Nervous System) which includes A. The nerves, and B. Their ganglia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What and where is the CNS?

A

Central Nervous System consists of the brain and spinal cord, and they occupy the cranium and vertebral canal. (Dorsal Body Cavity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What and where is the PNS?

A

Peripheral Nervous System is outside of the CNS, and includes both spinal nerves and cranial nerves.
Peripheral nerves link all regions of the body to the CNS.
CRANIAL NERVES EXTEND FROM THE BRAIN and carry signals to and from the brain.
SPINAL NERVES EXTEND FROM SPINAL CORD and carry signals to and from spinal cord.
GANGLIA are clusters of neuronal cell bodies located outside of CNS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What and where is the CNS?

A

Central Nervous System consists of the brain and spinal cord, and they occupy the cranium and vertebral canal. (Dorsal Body Cavity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is Motor Output?

A

Motor (efferent) signals are carried away from the CNS by nerve fibers of the PNS to innervate muscles to contract and/or glands to secrete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is Sensory Input?

A

Sensory (afferent) signals picked up by sensory receptors throughout the body and are carried by nerve fibers of PNS to the CNS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What exactly does the Nervous System do then? (Big picture)

A

Processes and interpret SENSORY INPUT and makes decisions on what should be done- a process called INTEGRATION
Dictates a response by activating effector organs (muscles or glands, for example) to produce a MOTOR OUTPUT RESPONSE

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the regions that Sensory Input and Motor Output serve?

A

SOMATIC BODY REGION: structures external to the ventral body cavity, i.e. outer tube (skin, skeletal musculature, axial bones) and appendicular bones and muscles.

VISCERAL BODY REGION: contains viscera within the ventral body cavity, i.e. inner tube (digestive tube, lungs, heart, spleen, bladder, etc.) as well as smooth muscle and glands throughout the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Tell me about the neuron.

A

The human body contains billions of neurons.
They are the basic structural unit of the nervous system, they are large, complex cells.

They contain a cell body, and arm-like neuron processes (dendrites and axons) extend from cell bodies.

Conduct electrical impulses from one part of the body to another

Signals travel very rapidly and are transmitted along the plasma membrane in the form of nerve impulses (action potentials)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the types of nervous tissue cells?

A
  1. NEURONS - excitatory cells

2. NEUROGLIAL CELLS- non-conducting cells that wrap around, nourish, insulate, and protect the delicate neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the cell body of a neuron.

A

Size varies from 5-140 micrometers.
In most neurons, the plasma membrane of the cell body acts as a receptive surface that receives signals from other neurons!
Has a single nucleus surrounded by cytoplasm.
Cytoplasm contains all the usual organelles as well as CHROMATOPHILIC BODIES (NISSI BODIES) which are free clusters of rough ER and free ribosmes.
NEUROFIBRILS - bundles of intermediate filaments which form a network between chromatophilic bodies and prevent the cell from being pulled apart when subjected to tensile forces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where are these neuron cell bodies located?

A

Most neuron cell bodies are located in the CNS, however, there are clusters of cell bodies in ganglia in the PNS (peripheral nervous system).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the cell body of a neuron.

A

Size varies from 5-140 micrometers.
In most neurons, the plasma membrane of the cell body acts as a receptive surface that receives signals from other neurons!
Has a single nucleus surrounded by cytoplasm.
Cytoplasm contains all the usual organelles as well as CHROMATOPHILIC BODIES (NISSI BODIES) which are free clusters of rough ER and free ribosmes.
NEUROFIBRILS - bundles of intermediate filaments which form a network between chromatophilic bodies and prevent the cell from being pulled apart when subjected to tensile forces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are these cell bodies located?

A

Most neuron cell bodies are located in the CNS, however, there are clusters of cell bodies in ganglia in the PNS (peripheral nervous system).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are axons? (neuron process)

A

AXONS - The neuron only has one axon which originates from a cone-shaped region of the cell-body called the AXON HILOCK.
Axons have a uniform diameter throughout the length.
Axons are impulse generators and conductors.
They transmit impulses away from the cell body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are dendrites? (neuron process)

A

DENDRITES - Processes that extensively branch from the cell body.
They function as receptive sites for receiving signals from other neurons.
They transmit electrical signals toward the cell body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the length of an axon?

A

Neurons may be long or short. Axons of motor nerves innervating foot extend from lumbar spine and a single axon can be 3-4 feet long!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How is an axon structure supported?

A

Neurofilaments, actin microfilaments, and microtubules provide structural strength along length of axon.
This structural support aids in AXONAL TRANSPORT of substances to and from the cell body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Do axons branch?

A

Axons branch far less frequently than dendrites.
Axon branches develop at more or less 90 degree angles to develop axon collaterals.
Branches usually occur at the terminus of the axon and referred to as TERMINAL BRANCHES
The end in knobs called AXON TERMINALS, also called end bulbs or boutons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the difference between a neuron, nerve fiber, and nerve?

A

NEURON - Nerve cell
NERVE FIBER - long axon of neuron
NERVE - Collection of parallel running nerve fibers in the PNS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a nerve impulse?

A

Nerve impulses are generated where the axon extends from the axon hillock.
Nerve impulses are conducted along the axon to axon terminals.
Nerve impulses release neurotransmitters from axon terminals into extracellular space (synaptic cleft) where they excite or inhibit neurons or target organs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

So how do neurons interact with each other?

A

Two neurons are connected by a synapse.
Axon terminal of pre-synaptic neuron and the pre-synaptic membrane in the first neuron.
Neurotransmitters are spewed out from the first neuron through the SYNAPTIC CLEFT.
The 2nd neuron has a postsynaptic membrane (I think) and have a post-synaptic dendrite of post-synaptic neuron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is a synapse?

A

The synapse is the site at which neurons communicate.
Most synapses in the nervous system transmit information through chemical messengers. Signals pass across synapse in one direction.
PRESYNAPTIC NEURON - conducts signal toward a synapse.
POSTSYNAPTIC NEURON - transmits electrical signal away from a synapse.

Most synapses in the CNS function w/ both presynaptic (info-sending) and postsynaptic (info-receiving) neurons; synapses get info from certain neurons and pass the info on to other neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Give me some more detail on a synapse.

A

Synapses are elaborate cell junction.
SYNAPTIC VESICLES - on presynaptic side.
Synaptic vesicles are membrane bound sacs containing neurotransmitter chemicals that transmit messages across the synapse.
Mitochondria is abundant in axon terminals to provide energy for the secretion of neurotransmitters.
SYNAPTIC CLEFT - Separates the plasma membrane of two neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is a synapse?

A

The synapse is the site at which neurons communicate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Give me some more detail on a synapse.

A

Synapses are elaborate cell junction.
SYNAPTIC VESICLES - on presynaptic side.
Synaptic vesicles are membrane bound sacs containing neurotransmitter chemicals that transmit messages across the synapse.
Mitochondria is abundant in axon terminals to provide energy for the secretion of neurotransmitters.
SYNAPTIC CLEFT - Separates the plasma membrane of two neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the 3 structural classifications of neurons?

A
  1. Multipolar neurons: >2 processes; interneurons and motor neurons; 99% of neurons in body
  2. Bipolar neurons: 2 Processes; special sensory function
  3. Unipolar (pseudounipolar): 1 process; sensory function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is a multipolar neuron?

A

Multipolar neurons possess >2 processes.
Typically have many processes extending from the cell body with multiple dendrites and one axon.

Multipolar neurons make up >99% of neurons in the body
Some examples are interneurons and motor neurons!
Most are interneurons (association neurons) that conduct impulses within the CNS.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is a bipolar neuron?

A

Possess two processes that extend from opposite sides of the cell body; one is a fused dendrite and other is an axon.

  • Rare
  • It is found in some special sensory organs (like the inner ear, olfactory epithelium of the nose, retina of the eye).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is a unipolar neuron?

A
  • Possess one short, single process near the neuron cell body
  • This single process divides into two longer branches: one branch (axon) extends to the CNS (CENTRAL PROCESS) and one branch (“dendritic axon”) extends peripherally to the receptors (PERIPHERAL PROCESS)
  • Most start as bipolar neurons during development and are hence called pseudounipolar
  • Found in sensory ganglia of the PNS, where they function as sensory neurons
  • Common in dorsal root ganglia along spinal cord and the sensory ganglia of cranial nerves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the 3 functional classification of neurons?

A 
Functional classification is determined according to the direction the nerve impulse travels relative to the CNS
Three types of neurons:
1. Sensory neurons
2. Motor neurons
3. Interneurons
32
Q

What are sensory neurons (afferent neurons)?

A

Sensory neurons (afferent neurons): transmit impulses TOWARD THE CNS
-Virtually are all UNIPOLAR neurons
CELL BODIES ARE IN GANGLIA OUTSIDE THE CNS
- Short, single process extends from cell body and divides into
A. THE CENTRAL PROCESS (AXONAL): runs centrally into the CNS
B. THE PERIPHERAL PROCESS (“dendritic axon): extends peripherally to receptors

33
Q

What are motor neurons (efferent neurons)?

A
  • Motor neurons carry impulses AWAY FROM THE CNS to effector organs (muscles and glands)
  • Most motor neurons are MULTIPOLAR
  • CELL BODIES ARE WITHIN THE CNS
  • Form junctions with effector cells causing muscles to contract or glands to secrete
34
Q

What are interneurons (association neurons)?

A
  • Confined to the CNS… Most are multipolar
  • Lie between motor and sensory neurons
  • Integrate sensory input and motor output
  • May be a single neuron connecting sensory and motor neurons or one of a chain of CNS neurons
  • Link into chains that form complex neuronal pathways
  • Show great diversity in size and branching patterns
  • Interneurons make up 99.98% of the neurons in the body!!! Which reflects that vast amount of information processed in the human CNS
35
Q

What are the characteristics of neurons?

A
  • EXTREME LONGEVITY - can live and function for a longtime
  • MOST DO NOT HAVE ABILITY TO GO THROUGH MIOTIC DIVISION - Most fetal neurons lose their ability to undergo mitosis; neural stem cells are located in some areas of the CNS which can divide
  • HIGH METABOLIC RATE - require abundant oxygen and glucose; neurons die after five minutes without oxygen
36
Q

What are the supporting cells in the nervous system?

A

Neuroglial (glial) cells

37
Q

What are neuroglial cells?

A

-They provide supportive functions for neurons
-Cover nonsynaptic regions of neurons, insulating the neurons and keeping the electrical activites of adjacent neurons from interfering with each other!
-There are six types of supporting cells:
A. Four in the CNS
B. Two in the PNS

38
Q

What are the 4 types of CNS neuroglial cells?

A
  1. Astrocytes, the most common CNS type
  2. Oligodendrocyte cells have processes that form myelin sheaths around CNS nerve fibers
  3. Microglial cells are defensive types
  4. Ependymal cells line cerebral fluid filled cavities
39
Q

What are the two types of PNS neuroglial cells?

A
  1. Satellite cells surround neuron cell bodies

2. Schwann cells form myelin sheaths and surround axons

40
Q

Tell me a bit more about neuroglial cells in the CNS

A

They are non-nervous supporting cells.
They are smaller than neurons. They outnumber neurons 10 to 1.
Glial cells have branching processes and a central cell body
Make up half the mass of the brain
They can divide in mitotic division throughout life (most neurons are not able to do this)

41
Q

What are ependymal cells?

A

A type of neuroglial cell in the CNS.
They form a simple epithelium that lines the central cavity of the spinal cord and brain.
Ependymal cells are a fairly permeable layer between the cerebral spinal fluid and the tissue fluid that baths the cells of the CNS.
They bear cilia which help circulate the cerebrospinal fluid.

42
Q

What are microglial cells?

A

Microglial cells are the smallest and least abundant glial cell. They have elongated cell bodies with cell processes with many pointed projections.

Phagocytes - the macrophages of the CNS. They migrate to and engulf dead neuron and invading microorganisms.

They appear to support maturation of synaptic clefts. Microglial cells actually do not originate from nervous tissue, but they are derived from blood cells called MONOCYTES which migrate to CNS during embryonic and fetal stages.

43
Q

What is the structure of astrocytes?

A

Astrocytes are the most abundant glial cell type.
They have radiating processes with bulbous ends which cling to neurons and/or capillaries.
They extract blood sugar from capillaries for energy.

44
Q

What is the function of astrocytes?

A

Astrocytes sense neuron release of neurotransmitters. They regulate neurotransmitter levels by increasing uptake in regions of high neuronal activity.

Astrocytes signal increased blood flow through capillaries in active regions of the brain. They take up and release ions to influence ionic environment around neurons.

Astrocytes help synapses form in developing neural tissue. They produce molecules necessary for neural development (like brain-derived trophic factor). They also propagate calcium signals that may be involved in memory.

45
Q

What kind of axon is associated with unmyelinated axons in CNS?

A

The thinnest axons in CNS are unmyelinated, and covered by many long processes of glial cells (astrocytes)

46
Q

What are oligodendrocytes?

A

Oligodendrocytes are neuroglia in the CNS. They have fewer branches than astrocytes. They line up in small groups and wrap their cell processes around the thicker axons in the CNS.

Oligodendrocytes produce insulating coverings called MYELIN SHEATHS. A single oligodendrocyte may have multiple processes that coil around and myelinate several different axons. They also are involved in the Nodes of Ranvier.

47
Q

What are myelin sheaths (of the CNS)?

A

Myelin sheaths are produces by oligodendrocytes in the CNS and Schawnn cells in PNS. They surround thicker axons.

They are segmented structures composed of the lipoprotein MYELIN. Each segment of myelin consists of plasma membrane of a supporting cell rolled in concentric layer around the axon.

They form an insulating layer which prevents leakage of electrical current from the axon. They increase the speed of impulse conduction.

48
Q

What is multiple sclerosis?

A

The immune system attacks the myelin around axons in the CNS. The intensity varies widely among the affected… but more women have it than men. When men are effected, the disease develops quicker and is more devastating.

49
Q

What are the neuroglia in the PNS?

A
  1. Satellite cells - surround neuron cell bodies within ganglia
  2. Schwann cells - Surround axons in the PNS and form myelin sheaths around many of these axons.
50
Q

Describe Myelin Sheaths in the PNS

A

Myelin Sheaths in the PNS are formed by Schwann cells. For myelinated axons, each schwann cell contributes myelin to one axon. Each Schwann cell wraps in concentric layers around the axon to produce a tightly packed coil of membranes called the myelin sheath.

Neurilemma (Sheath of Schwann) is the outermost nucleated cytoplasmic layer of Schwann cells external to myelin sheath layers.

Nodes of Ranvier are gaps along axon between adjacted Schwann cells. Schwann cells develop during the fetal period and in the first year of post-natal life.

51
Q

What is the difference between thick and thin axons in the PNS?

A

Axons in the PNS have both thick and thin axons. Thick axons are myelinated, thin axons are unmyelinated and conduct impulses more slowly.

52
Q

Describe thin, unmyelinated axons in the PNS

A

Thin axons are unmeylinatd, and thus, conduct impulses more slowly. Schwann cells surround thing axons but do NOT wrap around in concentric rings and do NOT form a myelin sheath.
A single Schwann cell can surround multiple UNMYELINATED axons. Thin axons are found in portions of the autonomic nervous system and in some sensory fibers.

53
Q

Describe the nerves of the PNS

A

Nerves - cable-like structures in the PNS. They consist of numerous parallel axons wrapped in connective tissue. Nerves can contain both myelinated and unmyelinated sensory and motor nerve fibers (axons).

54
Q

What is the difference between a neuron, nerve fiber, and nerve in the PNS?

A

Neurons: nerve cells
Nerve fibers: long axons
Nerve Fascicles: groups of axons bound into bundles by connective tissue wrapping within a nerve.
Nerve: collection of nerve fibers running in parallel in the PNS.

54
Q

What is the difference between a neuron, nerve fiber, and nerve in the PNS?

A

Neurons: nerve cells
Nerve fibers: long axons
Nerve Fascicles: groups of axons bound into bundles by connective tissue wrapping within a nerve.
Nerve: collection of nerve fibers running in parallel in the PNS.

55
Q

What is gray matter in the spinal CNS?

A

It is gray-colored and surrounds hollow central cavities of the CNS.
It forms butterfly-shaped region in the spinal cord.
-Site where neuron cell bodies are clustered.
Dorsal half contains cell bodies of interneurons, ventral half contains cell bodies of motor neurons.
Primarily composed or neuronal cell bodies, dendrites, short, unmyelinated axons of interneurons, and neuroglia.

55
Q

Describe nerves in the PNS

A

Within a nerve, each axon is surrounded by Schwann cells.
1. Endonerium- Layer of delicate connective tissue covering the Schwann cells surrounding the axons.
2. Nerve fascicles - groups of axons bound into bundles by connective tissue wrapping called the perineurium.
3. Epineurium - Tough, fibrous sheath which surround nerve.
The connective tissue in a nerve also contain blood vessels that nourish the axons and Schwann cells.

56
Q

What is white matter in the CNS?

A

The myelin around the myelinated axons gives that white matter its color.
White matter is composed of bundles of many myelinated axons. TRACTS are bundles of axons passing between specific regions of the CNS.
Most of these axons either ascend from the spinal cord to the brain, or descend from the brain to the spinal cord.
White matter connects various grey matter areas (locations of nerve cell bodies) of the CNS to each other.

57
Q

What is the difference between gray matter and white matter of the CNS?

A

Grey matter is rich in neuronal cell bodies.
White matter lacks neuronal cell bodies.
Grey matter consists mainly of unmyelinated axons.
White matter contains predominantly myelinated axons.

58
Q

What is the relationship between the PNS and CNS?

A

The CNS and PNS are functionally interrelated.
The PNS is composed of axons of sensory (afferent) and motor (efferent) neurons bundled together as nerves.

Nerves of the PNS function as information pathways to and from the body periphery.
Afferent PNS fibers respond to sensory stimuli.
Efferent PNS fibers transmit motor stimuli from CNS to muscles and glands.

Neurons of the PNS synapse w/ neurons of the gray matter, creating a network of ramps that link the ‘roadways’ of the PNS w/ the superhighways of the CNS (white matter)

White matter pathways in the CNS are formed by long, myelinated axons that extend out from the gray matter.

59
Q

Positional relationship of white matter and gray matter

A

Throughout the CNS, the gray matter surrounds the hollow central cavity and is internal to the white matter.
In two regions of the brain (cerebrum and cerebellum) there is an additional thin layer of gray mater (cortex) located externally to the white matter.

60
Q

What are reflex arcs?

A

They are simple chains of neurons. They explain our simplest reflex behaviors. They determine structural plan of the nervous system.

Reflex arcs are responsible for REFLEXES- rapid involuntary automatic motor responses to stimuli.

Reflexes can be somatic (skeletal muscle) or visceral (smooth muscle, cardiac, or glands).

61
Q

What are the interneurons in the CNS?

A
  1. Gray matter interneurons:
    A. Process and receive sensory information.
    B. Direct information to specific CNS regions and/or cell bodies of motor neurons in ventral spine.
    C. Initiate appropriate motor responses.
  2. White matter interneurons:
    A. Transport information (sensory and motor) from one area of the CNS to another.
62
Q

Describe the integration center

A
  • In the simplest reflex arcs, the integration center is a single synapse (monosynaptic) between a sensory neuron and a motor neuron.
  • In more complex reflexes, the integration center involves MULTIPLE SYNAPSES (POLYSYNAPTIC)
63
Q

What are the five essential components to the reflex arc?

A
  1. Receptor - at terminal end of sensory nerve - site where stimulus acts
  2. Sensory neuron - transmits afferent impulses to the CNS
  3. Integration center - consists of one or more synapses in the grey matter of the CNS
  4. Motor neuron - conducts efferent impulses from integration center to an effector
  5. Effector - is muscle or gland cell that responds to efferent impulses by contracting or secreting
64
Q

Describe the integration center

A
  • In the simplest reflex arcs, the integration center is a single synapse (monosynaptic) between a sensory neuron and a motor neuron.
  • In more complex reflexes, the integration center involves MULTIPLE SYNAPSES (POLYSYNAPTIC)
65
Q

Monosynaptic Reflexes

A

The simplest of all reflexes with a sensory neuron and motor neuron. It has…

1 Synapse
1 Sensory neuron
1 Motor Neuron
0 Interneurons
Very fast!

Stretch reflexes include “knee-jerk” reflex and reflexes which help maintain equilibrium and upright posture. Stretch reflexes are the FASTEST of all body reflexes.

66
Q

Polysynaptic Reflexes

A

More common type of reflex

1 or more interneurons are part of the reflex pathway between the sensory and motor neurons.

MOST of the simple polysynaptic reflex arcs (such as a withdrawal reflex in response to a pricked finger) have a single interneuron between the sensory and motor neurons, and thus have two synapses and 3 neurons

67
Q

What is an example of a diverging circuit?

A

One presynaptic neuron synapses with multiple other neurons (divergence)

Stretch of a muscle stimulates numerous sensory neurons which synapse with 100-150 neurons in the spinal cord gray matter.
Some are motor neurons which directly innervate the stretch muscle and stimulate contraction.
Other examples are interneurons that act to inhibit the activity of the antagonistic muscle group.
Other examples are interneurons that project sensory info to the brain.

68
Q

What are the three neuronal circuits?

A
  1. Diverging circuits
  2. Converging Circuits
  3. Reverberating circuits
69
Q

What is a reverberating circuit?

A

One neuron in the circuit receives feedback from another neuron in the same circuit; a branch off the axon of one neuron circles back and synapses w/ previous neuron in the circuit.. involved in control of rhythmic activities (breathing).

70
Q

What is a converging circuit?

A

Many neurons synapse on a single postsynaptic neuron (covergence) and a single motor neuron may receive both excitatory/inhibitory messages.

71
Q

Example of parallel processing: withdrawal reflex

A

Withdrawal Reflex: a painful stimulus triggers nerve impulses in a sensory neuron, which initiate the withdrawal reflex.

Parallel Processing: simultaneously, the nerve impulses travel in an axon branch that extends into the spinal white matter and extends up to the brain as an ascending pathway

72
Q

What is serial processing?

A

(Input Processing)
Serial Processing: neurons pass a signal to a specific destination in sequence (in series along a single pathway from one neuron to the next)
-examples of serial processing include, a reflex arc or a long chain of interneurons carrying a sensory signal to the brain

73
Q

Example of parallel processing: withdrawal reflex

A

Withdrawal Reflex: a painful stimulus triggers nerve impulses in a sensory neuron, which initiate the withdrawal reflex.

Parallel Processing: simultaneously, the nerve impulses travel in an axon branch that extends into the spinal white matter and extends up to the brain as an ascending pathway

74
Q

Example of parallel processing: Integration in gray matter and voluntary motor response

A

Integration in gray matter: Multiple interneurons process the nerve impulses to localize the stimulus, identify its source, and plan a response

Voluntary motor response: A voluntary (non-reflexive) motor response is initiated in the cerebral gray matter and is transmitted down a descending fiber in the white matter to stimulate somatic motor neurons (like deciding to run cold water over a burned finger)

75
Q

Input Processing: Parallel Processing:

A
  • A single sensory stimulus results in multiple perceptions
  • Information from a single neuron is sent along two or more parallel pathways allowing a single sensory stimulus to result in multiple perceptions
  • Allows brain to rapidly evaluate stimuli and enables info to be processed and integrated along multiple pathways
  • When you see a dog approaching, there are multiple processing pathways triggered in parallel by the sensory visual stimulus including evaluation of shape, color, spatial location, movement, as well as memory from past experiences w/ dogs.

Anatomy (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions