Introduction To Nervous System Flashcards
The Nervous system
An exquisite and complex information processing system
Inout—-> analysis—> Outputs
Consists of an input that could be either external (Sensory) or Internal (Hormonal)
The Neuron
Electrical cell of the nervous system
Axon soma dendrites
Embryonic Development
The anterior end of the neural tube gives rise to three primary brain vesicles
Prosencephalon—> forebrain
Mesencephalon—> midbrain
Rhombencephalon—> hindbrain
Secondary brain vesicles of the forebrain (prosencephalon)
Telencephalon
Diencephalon
Telencephalon
The adult brain structures : cerebrum—> cerebral hemisphere (cortex, white matter, basal nuclei) hippocampus
Adult neural canal regions: Lateral ventricles
Functions of Telencephalon
Thinking,learning,memory,consciousness
Definition of Basal Nuclei
Collection of nuclei that modulate motor functions of cerebral cortex
Hippocampus’s role?
Plays an important role in memory and spatial learning
Diencephalon
Adult brain structures: (thalamus,hypothalamus,epithalamus), retina
Adult neural canal region: third ventricle
Function of the Thalamus
Sensory relay
Function of Hypothalamus
Homeostasis
Cerebellar Divisions
Cerebrocerebellum: lateral hemisphere
Spinocerebellum: Vermis, Intermediate hemisphere
Reticular Formation
Contain loosely organized interconnected collection of neurons and fibers called reticular formation
Floculo-nodular lobe
Vestibulocerebellum
Secondary brain vesicles of the midbrain(Mesencephalon)
Mesencephalon
Secondary brain vesicles of the forebrain( Rhombencephalon)
Metencephalon
Myelencephalon
Brain stem respiratory centers
Pneumotaxic area
Apneustic Area
Rhythmicity Area
Cranial Nerves
Olfactory nerve (CN I)
Optic nerve (CN II)
Oculomotor nerve (CN III), Trochlear nerve (CN IV), Trigeminal nerve (CN V), Abducens nerve (CN VI), Facial nerve (CN VII), Vestibulocochlear nerve (CN VIII)
Glossopharyngeal nerve (CN IX)
Vagus nerve (CN X) Accessory nerve (CN XI)
Hypoglossal nerve (CN XII).
Pons
- Contains somatic motor neurons that control nucleus
- Nucleus for CN V
- Nucleus for CN VI
- Nucleus for CN VII
- Receives somatic sensory information from the face,scalp,mouth, and nose ( portion of the nucleus for CN V)
Medulla
-Nuclei of CN IX and X
- The medulla contains somatic motor neurons that innervate the:
- Nucleus of CN XI
- Nucleus of CN XII
Spinal cord
Most caudal region in the CNS
Gray Matter ( Spinal Cord)
Dorsal Horns
Ventral Horns
Lateral Horns (only in thoracic and lumbar regions)
- sympathetic neurons
Dorsal root (Spinal) ganglia
- Contain cell bodies of sensory neurons
White Matter (Spinal Cord)
- Consists mostly of ascending (sensory) and descending (motor) tracts
- Transverse tracts (commissural fibers) cross from one side to the other
- Tracts are located in three white columns (funiculi on each side- dorsal (posterior), lateral
Peripheral Nervous System
- Nervous structures outside the brain and spinal cord
-Nerves allow the CNS to receive information and to take action - Functional components of the PNS
- Sensory inputs and motor outputs categorixed as somatic or visceral
- sensory inputs also classified as general or special
PNS Afferent Division
Afferent (sensory) division
- Somatic afferent fibers
- Visceral afferent fibers
Afferent ( sensory) division
Transmits impulses from receptors to the CNS
Somatic afferent fibers
Carry impulses from skin, skeletal muscles, and joints
Visceral afferent fibers
Transmit impulses from visceral organs
PNS Efferent Division
Motor (efferent) division
- Somatic
- Autonomic
Motor (efferent) division
Transmits impulses from the CNS to effector
Somatic efferent fibers
Provides conscious control of skeletal muscles
Autonomic fibers
Regulates smooth muscle, cardiac muscle, and glands
