unit 5 : organization of the nervous sytem Flashcards
what does the brain do?
sensation/perception, movement, maintain the internal environment, tells time, preservation of the species, adaptation
divisions of the nervous sytem
central and peripheral nervous systems
central nervous system
brain + spinal cord
peripheral nervous system
autonomic nervous system (sympathetic and parasympathetic nervous system) + somatic nervous system
enteric nervous system
one of the main divisions of the autonomic nervous system and consists of a mesh-like system of nerves that governs that function of the GI tract
- it can act independently of the sympathetic and parasympathetic nervous systems, although it may be influenced by them
the nervous system develops from
the neural crest cells of the ectoderm, the surface layer of embryonic tissue
neural crest cells will differentiate into separate groups of neurons
these groups include sensory neurons of cranial nerve ganglia, dorsal root ganglia, autonomic ganglion cells of the sympathetic and parasympathetic nervous system. in addition, these cells become endocrine cells
brain ventricular system
a series of connecting hollow spaces called ventricles that are filled with cerebrospinal fluid.
- consists of two lateral ventricles, the third ventricle, and the fourth ventricle
forebrain
telencephalon
- cerebral hemispheres
- amygdala
- hippocampus
- basal ganglia
- septum
diencephalon
- thalamus
- hypothalamus
hindbrain
cerebellum, pons, medulla
brain stem
diencephalon
- thalamus
- hypothalamus
midbrain
hindbrain
- cerebellum
- pons
- medulla
dermatome
an area of skin that is mainly supplied by a single spinal nerve, each nerve relays sensation from a particular region of skin to the brain
vertebrae
cervical, thoracic, lumbar, sacral, and coccygeal segments
gray matter
made up largely of cell bodies, whereas the white matter is made up of fiber tracts that ascend and descend to and from the brain.
the gray matter contains
the cells of the spinal cord
the white matter contains the
axon/fiber pathways
medulla oblongata
responsible for autonomic functions ranging from vomiting to sneezing.
- contains the cardiac, respiratory, vomiting, and vasomotor centers and theregore deals with the autonomic functions of breathing, heart rate, and blood pressure
pons
notable for containing nuclei of the reticular formation, which plays a crucial role in maintaining behavioral arousal and consciousness, and also is important for having several areas that control the changes in physiological variables that occur when we move from arousal to sleep and sleep to arousal
- major crossing of fibers from one side of the brain to the other
cerebellum
important for the control of complex, coordinated behaviors
- has two hemispheres and a structure called the vermis
- the middle parts, including the vermis are important for smoothing out of movements.
- the lateral parts are important for coordinating skilled movements that involve sequences of behavior in real time - like learning to make a bank shot in basketball
- also involved in teh acquisition of motor skills
the acquisition of complex motor skills requires
numerous reciprocal connections between the cerebellum and motor contex
tegmentum
ventral and below the cerebral aqueduct
periaqueductal gray
lies adjacent to the cerebral aqueduct and is important for pain perception. it is a source of neurons that make opiate-like neurotransmitters called endorphins and contains receptors that bind endorphins and other opiate like substances.
sources of efferent cranial nerves and terminal nuclei of afferent cranial nerves
Cranial nerves are the nerves that emerge directly from the brain, in contrast to spinal nerves. 10 of the cranial nerves originate in the brainstem. Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck. The motor nuclei are located ventrally (as in the spinal cord) while the sensory nuclei are located dorsally (also as in the spinal cord)
thalamus
top of the brainstem and is one of the largest collections of nuclei in the brain
- processes the information and then passess it on to the appropriate primary sensory cortex for further processing