Nervous system Anatomy Flashcards
Causes of Lesions to the Nervous system
- traumatic
- vascular
- degenerative
- neoplasms
- inflammation
- immunologic disorders
- metabolic disorders can cause damage
Rostral
- toward the head
and - anterior
Caudal
- toward the tail or coccyx
- posterior
dorsal
- superior to the brain
- posterior to the spinal cord
Ventral
- inferior to the brain
- anterior to spinal cord
Dura mater
- “tough covering”
- outermost
- two layers
Arachnoid
- spider like
- middle layer
pia mater
- soft covering
- innermost
Nervous system regions
- cerebrum
- brainstem and cerebellum
- spinal region
- peripheral NS
Somatic nervous system
- innervates cutaneous and MSK structures
Autonomic nervous system
innervates viscera
Special sensory system
innervates visual, auditory, vestibular, olfactory, and gustatory (taste) structures
Neurons functions
- receives information
- processes information
- generates an output by releasing neurotransmitters
Function of the Nucleus:
- Control center
- contains the neuron’s genetic material,
- directs the metabolic activity of the neuron
Function of the Golgi apparatus
package NT
Neuron soma (cell body)
Not as a function but rather what they are called
- usually located in groups
- gray matter (integration occurs)
- in PNS called ganglia
- in CNS = nucleus or cortex
bundles of myelinated nerve fibers
- white matter
- in PNS = nerve, nerve cord, nerve trunk, ramus
- in CNS = tract, fascicles, peduncle, column, lemniscus
Nerve
-a bundle of neurons that convey signals between the brain, spinal cord, and other parts of the body
Ramus
-Branch of a spinal nerve.
Tract
Tract-A bundle of axons with the same origin and a common termination
Fasciculus/fasciculi
- A group of axons with the same function traveling together in the CNS
Peduncle
-band of white matter joining different parts of the brain
Column
White matter in the lateral and anterior spinal cord
Lemniscus/lemnisci
A bundle of myelinated axons with the same function travelling together in the CNS
Astrocytes
- largest most numerous glial cells
- found throughout CNS
- connect neurons and capillaries
- pathway for migrating neurons in early CNS development
- communicate with other astrocytes and neurons
- essential in cleaning/regulated and maintaining stability of extracellular environment
Microglial cells
- distributed throughout CNS mostly in grey matter
- Small glial cells with long, branched, antler-like processes. “Hang out” at rest, with their branches sticking out to monitor extracellular fluid. Continually sample extracellular environment for indicators of damage.
- 1º immune effector cells of CNS. Are activated after CNS damage (injury, infection, disease). Draw in their branches, divide, and “head over” to affected neurons. Clean up debris from dying cells. Essential for normal healing
- first line of immune defense against damage or infection
- normally function as phagocytes after injury, infection, disease
Spinal cord functions
- to convey information between neurons in periphery and the brain
- processes some information
What are spinal nerves connected to the spinal cord by
a dorsal root (sensory) and a ventral root (motor)
What is the dorsal root ganglion
- bodies of sensory neurons
- pseudo unipolar
- SAD DAVE (Sensory = Afferent = Dorsal, Dorsal Afferent Ventral Efferent)
What marks the transition from the spinal to peripheral region
- axons attached to the cord are within the spinal region until the exit the IV foramen
- where the spinal nerve splits into ventral and dorsal rami
Brain stem region
- midbrain
- pons
- medulla
Cerebellum
Function: coordinate movement
Attached to posterior brain stem by 3 fiber bundles
- Superior peduncle
- Middle peduncle
- Inferior peduncle
Cranial nerves and where they arise in the Nervous system (CNS or PNS)
- Olfactory = CNS only
- Optic = CNS only
- Oculomotor = midbrain
- trochlear = midbrain
- Trigeminal = pons
- Abducens = pons
- Facial = pons
- Vestibulocochlear = Pons
- Glossopharyngeal = medulla
- Vagus = medulla
- accessory = medulla
- hypoglossal = medulla
Cranial nerves and sensory vs motor function
- Some Say Marry Money But My Brother Says Big Brains Matter More
Cerebrum
- Cerebrum consists of diencephalon and cerebral hemispheres.
- Basal ganglia is additional gray matter WITHIN white matter of hemispheres.
- These nuclei surround thalamus.
- Part of a motor control circuit.
Diencephalon
- hypothalamus: maintains body temperature, metabolic rate, and homeostasis
- thalamus: relays information to cerebral cortex
- epithalamus: regulates pituitary and adrenal glands
- subthalamus: involved in motor control
Cerebral hemispheres: lobes
- frontal: voluntary motion, initiation or movement, judgement
- temporal: sound and hearing
- parietal” body ischemia/position in space
- occipital: vision
Cerebral hemispheres: medial view limbic lobe
- limbic system
- emotions
- deep traumatic memories
Cerebral Sulci
Plus types
- groove
- Longitudinal fissure: Divides right & left hemispheres
- Central sulcus: Divides frontal & parietal lobes
- Lateral sulcus: Separates temporal lobe & frontal lobe
- Parietooccipital sulcus: Divides parietal & occipital lobes
- Cingulate sulcus: Divides limbic lobe
White matter deep to the cortex
- Corpus callosum: huge commissure connecting most areas of cerebral cortex. Age-related declines cause deficits in interhemispheric communication- ↓ bimanual coordination. (Larsen)
- Anterior commissure: smaller commissure connecting R and L temporal lobe cortices. (See slide 40)
- Corona radiata
Internal capsule: axons projecting between cortical and subcortical structures
Corona Radiata
- fibers from subcortical structures to cerebral cortex
- fibers from cerebral cortex to subcortical structures
- all fibers in corona radiate pass through internal capsule