Chap 3 - Anatomy and Research Methods Flashcards
CNS
brain
spinal cord
central nervous system
PNS
connects brain and spinal cord to rest of the body
- somatic nervous system
- autonomic nervous system
peripheral nervous system
somatic nervous system
consists of axons conveying messages from sense organs to CNS and from CNS to muscles
autonomic nervous system
controls heart, intestines, and other organs
Has some cell bodies w/in brain or spinal cord or in clusters along the sides of the spinal cord
ventral
towards the stomach
dorsal
towards the back
spinal cord
part of the CNS found w/in spinal column
Communicates with the sense organs and muscles, except those of the head
Bell-Magendie law
entering dorsal roots carry sensory information and exiting ventral roots carry motor information
dorsal root ganglia
Cell bodies of the sensory neurons are located in clusters of neurons outside the spinal cord
spinal cord is comprised of:
Grey matter
White matter
Each segment sends sensory information to the brain and receives motor commands
Grey matter
located in the center of the spinal cord and is densely packed with cell bodies and dendrites
White matter
composed mostly of myelinated axons that carries information from the gray matter to the brain or other areas of the spinal cord
autonomic nervous system
sends and receives messages to regulate the automatic behaviors of the body (heart rate, blood pressure, respiration, digestion, etc.)
- sympathetic nervous system
- parasympathetic nervous system
sympathetic nervous system
network of nerves that prepares the organs for rigorous activity:
- Increases heart rate, blood pressure, respiration, etc. (“fight or flight” response)
- Comprised of ganglia on the left and right of the spinal cord
Postganglionic axons of the parasympathetic nervous system mostly release ________ as a neurotransmitter.
acetylcholine
The sympathetic nervous system mostly uses _______.
norepinephrine
3 major divisions of the brain:
- hindbrain
- midbrain
- forebrain
Hindbrain
located at the posterior portion of the brain
Hindbrain structures, the midbrain, and other central structures of the brain combine and make up the:
brain stem
Medulla
Located just above the spinal cord and could be regarded as an enlarged extension of the spinal cord
- Responsible for vital reflexes such as breathing, heart rate, vomiting, salivation, coughing and sneezing
Cranial nerves
allow the medulla to control sensations from the head, muscle movements in the head, and many parasympathetic outputs to the organs
Pons
Lies on each side of the medulla (ventral and anterior)
- Along with the medulla, contains the reticular formation and raphe system
- Works in conjunction to increase arousal and readiness of other parts of the brain
Cerebellum
Structure located in the hindbrain with many deep folds
- Helps regulate motor movement, balance, and coordination
- Also important for shifting attention between auditory and visual stimuli
reticular formation
- Descending portion is one of several brain areas that control the motor areas of the spinal cord
- Ascending portion sends output to much of the cerebral cortex, selectively increasing arousal and attention
raphe system
sends axons to much of the forebrain, modifying the brain’s readiness to respond to stimuli
Midbrain
- Tectum
- Superior colliculus / inferior colliculus
- Tegmentum
- Substantia nigra
Tectum
roof of the midbrain
Superior colliculus and Inferior colliculus
processes sensory info
Tegmentum
contains nuclei for cranial nerves and part of the reticular formation
Substantia nigra
gives rise to the dopamine-containing pathway facilitating readiness for movement
Forebrain
most anterior and prominent part of the mammalian brain and consists of two cerebral hemispheres
- Consists of the outer cortex and subcortical regions
- Outer portion is known as the “cerebral cortex”
- Each side receives sensory information and controls motor movement from the opposite (contralateral) side of the body