Lecture 1 - Brain Cells Flashcards
White matter (inside) in brain is composed of
Axons
Gray matter (outside) in brain is composed of
Cell bodies
In the spinal cord the grey matter is where
Inside
In the spinal cord white matter is where
Outside
Action potentials are the conversion of what
Electrical signal to chemical signals
Motor neurons could be located where
Spinal region
Pyramidal cells could be located where
Cortex & hippocampus
Purkinjee cells could be located where
Cerebellum
Role of astrocytes (3)
- Provide nutrients from blood (which is important for BOLD signal in fMRI
- Maintain ion balance
- Send signals to neurons and other glia
What forms the myelin around neurons in the CNS
Oligos
Why is myelination important
- Limit plasticity
- Crucial for brain development
- Limits water diffusion — can be seen with diffusion tensor imaging
When does myelination occur
Post-natal
What causes the whitening in appearance of the infant brain in diffusion images between the ages of 3 months and 6 months?
Increase of myelination of axons that occurs through development
If action potentials are “all or none,” how does the nervous system code differences
in the strength or intensity of a sensory stimulus?
Action potentials of a neuron all have the same amplitude – neurons convey info about the strength or intensity of different sensory stimuli through their firing rate
2 types of glial cells
Astrocytes
Oligodendrocytes
