Notes Flashcards
Study of the nervous system
Neurology
- uses millions of sensory receptors to monitor changes occurring both inside and outside the body.
- it processes and interprets the sensory input and makes decisions about what should be done at each moment
- it dictates a response by activating the effector organs, our muscles or glands.
3 overlapping functions
- Sensory input
- integration
- motor output
Cell body- central section, Dendrites- filament like extension that acts as receiving units of impulses (electrical or chemical), Axons -long filament extension that transmits the impulse then passes onto the next dendrite
Neurons- Specialized cell made up of 3 parts.
Small gap between axon and dendrite
synapse
non-nervous tissue that surrounds and supports neurons
neuroglia
chains of neurons and the surrounding neuroglia
Nerves
- a _____ is a nerve cell
2. a ______ is a collection of axons in the PNS
- neuron
2. nerve
- consists of brain and spinal cord (dorsal cavity)
- part of the nervous system outside the CNS, consists mainly of the nerves that extend from the brain and spinal cord. Nerves in PNS are ganglia (areas where the cell bodies of neurons are clustered)
2 anatomical parts
- Central nervous system
- peripheral nervous system
signals are picked up by sensory receptors located throughout the body and carried by nerve fibers of the PNS into the CNS. These nerves detect pain, pressure, heat, nd texture.
Sensory ; afferent
Signals are carried away from the CNS by nerve fibers of the PNS to innervate the muscles and glands, causing these organs either to contract or to secrete.
Motor ; efferent
Consists of the structures external to the ventral body cavity - (skin, skeletal musculature, bones, etc.)
Somatic body region
mostly contains the viscera within the ventral body cavity; (digestive tube, lungs, heart, bladder, etc)
Visceral body region
- senses from skin
- kicking knee reflex
- stretched stomach, senses from inside organs
- heart beating, lungs and diaphragm, digestive movement
4 subdivisions of 2 regions for the nervous system
- Somatic sensory
- Somatic motor
- visceral sensory
- visceral motor
-also called “encephalon” ; outward appearance is wrinkled, combination of elevations and furrows
Brain
The elevations of the brain
gyri
The furrows of the brain
Sulci
name used to describe the outer portion of the brain because of its color.
-intellectual activity mostly resides here
gray matter
inner portion of the brain.
- reflex and instinctual behaviors arise here.
white matter
Right/left Lateral (Atrium) (upper) ; Right/left ventricle (lower)
4 open spaces inside the brain
Membranes that surrounds the CNS ; made up of 3 layers
Meninges
Outer most layer of the meninges
Dura mater
between the dura and Pia layers that is filled with cerebrospinal fluid. Acts as shock absorber for the brain and spine.
Subarachnoid space
Inner most layer of the meninges
Pia Mater
Cerebrum, cerebellum, and brain stem
3 subdivisions of the brain
largest portion of the brain. logic, reasoning and memory are ongoing functions here. 2 equal portions called hemispheres.
Cerebrum
Long medial fissure that separates the two hemispheres
longitudinal fissure
area near the floor of the cranial cavity where the two hemispheres are held together
corpus callosum
named for their proximity to cranial bones. Defined by smaller fissures.
Frontal, parietal, occipital, temporal
Four lobes of the cerebrum
Smallest portion of the brain. posterior and inferior part of the cranial cavity. Also divided by left and right hemispheres but no more subdivisions. Muscle coordination and balances comes from here.
Cerebellum
Most inferior part of the brain, below cerebrum and anterior to the cerebellum. Acts as relay center for impulses between brain and spinal cord. 3 important areas ______ controls ; respiration, heart rate, blood pressure.
Brain stem
Midbrain, pons varolii, and medulla oblongata
Brain stem’s 3 segments
center area of the brain. Divided into 2 sections; thalamus and hypothalamus
Diencephalon
Under the cerebrum and associated with the 3rd ventricle. thought to be related to special sense impulses (hearing, sight, touch, taste, pain)
thalamus
between thalamus and mid-brain. Small but important area. associated with pituitary gland, and regulation of horomones. Diuretic effect, body temp, circadian rhythms, and appetite.
hypothalamus
Attached to inferior end of brain stem and stays within the vertebral canal. “solid” portion extends from the foramen magnum of the occipital bone to near the second lumbar vertebra.
spinal cord
the end of the second lumbar to the coccyx is non-nervous tissue, essential Pia mater
film terminal
- In spinal cord, _____ matter makes up outside of cord.
2. In spinal cord, ____ matter forms “H” shape at the center of the cord.
- White
2. Gray
2 groups of nerves in the PNS
- Spinal nerves
2. cranial nerves
5 groups of spinal nerves in the PNS
- Cervical-brachial plexus
- thoracic plexus
- lumbar plexus
- sacral plexus
- coccygeal
Horsetail appearance of the nerves in the spinal cord
cauda equine
- olfactory - some
- optic - say
- ocolumotor - marry
- trochlear - money
- trigeminal - but
- abducens - my
- facial - brother
- vestibulocochlear - says
- Glossopharyngeal - bad
- vagus - business
- spinal accessory - marry
- hypoglossal - money
12 cranial nerves
