Chapter 1 Psychobiology Flashcards
What two parts is the Central Nervous System (CNS) comprised of?
Brain and Spinal Cord
What are the two divisions of the Peripheral Nervous System?
Autonomic and Somatic
What are the divisions of the autonomic nervous system?
Sympathetic and Parasympathetic
How many neurons are in the cerebral cortex?
12-15 billion
How many neurons are in the cerebellum
70 billion
How many neurons are in the spinal cord?
1 billion
What two types of cells comprise the human nervous system?
neurons and glia
What are neurons?
Highly specialized cells that possess electrical excitability, They function to process and transmit cellular signals.
What is a motor neuron?
- Receives excitation through its dendrites and conducts impulses along its axon to a muscle
- Neurons that carry outgoing information from the brain and spinal cord to the muscles and glands
- Efferent
- Soma is in the spinal cord
What is a sensory neuron?
Specialized at one end to be highly sensitive to a particular type of stimulation, such as light, sound or touch. neurons that carry incoming information from the sensory receptors to the brain and spinal cord: Afferent.
What is an interneuron/intrinsic neuron?
A neuron that carries nerve impulses from one neuron to another.
- dendrites and axons are completely contained within a structure
What are local neurons?
Neurons that have short axons, only exchange information with close neighbors, and do not produce action potentials.
What are Glial cells?
Greek for “glue”, glial cells provide support and protection for neurons. HSIFDCCC
• hold in place and surround
• supply nutrients & oxygen
• insulate
• form myelin
• destroy & remove decay & debris
• clearance of neurotransmitters & prevent toxic build-up
• can release certain neurotransmitters (e.g., glutamate)
• crucial to development (synaptic plasticity & genesis)
What is the glia to neuron ratio in cerebral gray matter?
3 glial cells for every 2 neurons.
What are the Glia cell types?
Astrocytes, Schwann Cells, Microglia, Oligodendrocytes, and Radial Glia (ASMOR)
Astrocytes are a type of glial cell that…
- synchronize the activity of the axon by wrapping around the presynaptic terminal and taking up chemicals released by the axon
Schwann cells are…
Glia in the PNS that build the myelin sheath that surrounds the axon of some neurons.
Microglia are….
Glia that remove waste material and other microorganisms that may be harmful to the neuron.
Oligodendrocytes are….
Glia in the CNS that build the myelin sheath that surrounds the axon of some neurons.
Radial Glia are….
Glia that guide the migration of neurons, & the growth of axons & dendrites during embryonic development.
Camilo Golgi (1843-1934)
Invented the neuronal cells staining procedure using silver chromate fixed to the neuronal membrane.
Santiago Ramon y Cajal (1852-1934)
Used Golgi’s cell-staining technique to develop the “neuron doctrine”.
- demonstrated that the individual cells comprising the nervous system remained separate but connected to each other by small zones [later called, synapses]
What are Purkinje cells?
Purkinje cells carry information primarily about body movement
- are aligned like dominos forming a 2-D grid
- cell outputs permit comparison of ongoing movement and sensory feedback derived from it
- thus, generates an error correction signal that can modify occurring movements
What are dendrites?
Dendrites are branching fibers lined with synaptic receptors.
- responsible for bringing in information from other neurons
- Dendrites - Sensory