nerves and neurons Flashcards
Biological psychology/ behavioral neuroscience
psychological processes on behavior and learning based on biology
Neuroscience
Branch of life science that deals with structure and function of neurons, nerves, and nervous tissue
first doctor who theorized neuroscience, what the theory was, and how they studied it
- Santiago Ramón y Cajal
- nervous system was made up of individual cells
- studied slides of brain tissue
cells
- is the nervous system’s building block
- Each cell has a special purpose, function, and therefore, structure
nucleus
the “brain” of the cell that contains its genetic material (DNA)
Cell body
also known as the soma, the part of the cell that contains the nucleus
Cell membrane
the semipermeable membrane enclosing the cell
neurons
basic cell that makes up, receives, and sends messages within the nervous system
Characteristics of the neuron:
- Messengers of the body
- Make up 10% of the brain
- Have special structures apart from other cells
dendrite
- Branch-like structures that receive messages from other neurons
- Attached to cell body/soma
Soma
- cell body of the neuron containing the nucleus and responsible for maintaining life of the cell
- Generally clump together near the spinal cord
axon
- tubelike structure that carries the neural message to other cells
- Allows neural messages to travel throughout the body
2 types of cells in the brain
- glial cells
2. radial glial cells
glial cells
- cells that provide support for neurons to grow on and around
- deliver nutrients to neurons, produce myelin to coat axons, clean up waste products and dead neurons, influence information processing, and, during prenatal development, influence the generation of new neurons
- Structures on which neurons develop and work, and that hold the neurons in place
myelin
a layer of fatty substance that coat axons of neurons to insulate, protect, and speed up the neural impulse
Radial glial cells
- guide migrating neurons to form outer layers of brain
- Extend from inner to outer areas like spokes of a wheel
2 types of glial cells that produce myelin
- Oligodendrocytes
2. Schwann cells
Oligodendrocytes
glial cells that produce myelin for the central nervous system
Schwann cells
glial cells that produce myelin for neurons of the peripheral nervous system
nerves
bundles of axons that are coated in myelin which travel together throughout the body
why do myelin-coated axons bundle together?
The axons form a cable that is much stronger and less vulnerable to breakage than a single wire alone
how does the myelin sheath speed up the neural message?
I. When the electrical impulse (neural message) travels down the axon, it “jumps” between nodes where axon is accessible
II. Nodes of Ranvier: small spaces on the axon not covered in myelin
III. This “jumping” allows the neural message to travel faster
What happens when the myelin sheath is damaged?
Multiple sclerosis (MS)
Multiple sclerosis (MS)
a disease where the myelin sheath is destroyed (possibly due to immune system), leading to diminished or complete loss of neuron functioning
early symptoms of MS
fatigue, changes in vision, balance problems, numbness, tingling, muscle weakness in limbs
