Nervous System 2 Flashcards
2 anatomic divisions
Central nervous system
Peripheral nervous system
Central nervous system
Brain
Spinal cord
Peripheral nervous system
Cranial nerves
Spinal nerves
2 functional divisions
Autonomic nervous system
Somatic nervous system
Autonomic nervous system
Sympathetic nervous system (consumes energy)
Parasympathetic nervous system (conserves energy)
Somatic nervous system
Initiation and control of voluntary movement
Pyramidal and extrapyramidal systems
Central nervous system consists of:
Spinal cord
Brain stem (medulla oblongata, pons, midbrain)
Cerebellum
Diencephalon
Cerebrum
Spinal cord
Divided into:
Cervical
Thoracic
Lumbar
Functions:
Receives and processes sensory information from skin, joints, and muscles of limbs and trunk
Carries down commands for motor movement to move and control the body from neck to the toes
Controls certain reflexes like knee jerk
Meningeal layers of the Brain:
Dura mater (subdural space)
Arachnoid mater (subarachnoid space, contains CSF)
Pic mater
Cerebral spinal fluid
Maintain constant exterior environment for neurons and glial
Mechanical cushion for brain during movement
Serves as part of lymphatic system/immune system and removes metabolic waste
Serves as route for certain types of hormones
The ventricles
CSF is connected with the 4 ventricles of the brain
Lateral ventricle
Third ventricle
Fourth ventricle
Cerebral aqueduct
Brain stem
Contains many clusters of specialized pathways that mediate the autonomic nervous system functions
Origin of cranial nerves
Brain stem functions
Receive sensory information from skin and muscles of the head
Provides motor control for head musculature
Relays sensory information from spinal cord to brain / vise versa
Regulates level of arousal and awareness through reticular formation
Brain stem: medulla oblongata
Mediates vital autonomic functions including digestion, breathing, and heart rate
Brain stem: pons
Relays motor input from cerebral hemispheres to cerebellum
Brain stem: midbrain
Coordinates many sensory and motor functions including eye movement and coordination
Cranial nerves: Olfactory and visual
I. Olfactory (S): smell
II. Optic (S): vision and visual acuity
III. Oculomotor (M): reaction to light, moves eyelids, visual tracking
IV. Trochlear (M): downward and lateral eye movement
VI. Abducens (M): lateral eye movement
Cranial nerves: CN V-Trigeminal
ANATOMIC DIVISIONS:
Ophthalmic branch
Maxillary branch
Mandibles branch
FUNCTIONAL DIVISIONS:
Sensory-carries cutaneous and proprioceptive sensation from skin, muscles, and joints of face and mouth
Motor-activates muscles of mastication
Cranial nerves: CN VII Facial nerve
Sensory-carried sensation from skin of external ear canal
Motor-activates muscles of facial expression
Autonomic activates:
Salivary glands
Lacrimal glands
Blood vessels of the cerebral cortex
Cranial nerves: CN VIII Vestibulocochlear nerve
Sensory (vestibular branch):
Conveys sensation of linear and angular/lateral acceleration
Cranial Nerves: CN IX Glossopharyngeal
Sensory-taste from posterior third of tongue / posterior palate and tonsillar fossae
Motor-innervates the stylopharyngeal muscle
Autonomic-innervates the parotid glands
Cranial Nerves: CN X Vagus nerve
Sensory-sensation from posterior pharynx, larynx, thoracic, and abdominal organs
Motor-innervates parts of the larynx and pharynx
Autonomic-innervates smooth muscle of the digestive system, lungs, blood vessels of the neck, thorax, and abdomen
Cranial nerve: CN XI Accessory nerve
Intrinsic muscles of the larynx, pharynx, and soft palate
Lateral movement and stability of the neck
Cranial nerve: CN XII Hypoglossal
Intrinsic muscles of the tongue
Cerebellum
Connected to brain stem via 3 peduncles (inferior, medial, and superior)
Modifies the force and range of movement
Diencephalon
Thalamus-processes most of the info reaching the cerebral cortex from the rest of the CNS
Gates sensory stimuli
Hypothalamus-regulates autonomic, endocrine, and visceral functions
