Flashcards in Levels of organisation in the nervous system Deck (53):
What is the nervous system divided into?
Central Nervous System (CNS)
Peripheral Nervous System (PNS)
What is the CNS divided into?
What is the PNS sub divisions?
Sensory (afferent) division
Motor (efferent) division
What is the sensory (afferent) division made up of?
Somatic sensory neurons
Visceral sensory neurons
What is the motor (efferent) division made up of?
Autonomic nervous system (involuntary)
Somatic nervous system (voluntary)
What are the 2 divisions of the Autonomic nervous system?
What is the spinothalamic pathway made up of?
What is grey matter?
High concentration of nerve cell bodies
What is white matter?
High concentration of nerve fibres/axons
Why is white matter white?
myelin gives the white appearance
What is ganglion?
Collection of nerve cells in CNS with particular function
What is a tract?
Nerve axons belonging to neurones of the same functional type (e.g. spinothalamic tract)
What is a pathway?
Collective set of neurons in conveying a signal from periphery to the cortex
What are spinothalamic neurons?
Long axon up to the brain terminates at the thalamus
What is the spinothalamic tract?
Sensory pathway from skin to the thalamus
What is the PNS formed of?
Afferent (sensory) and efferent (motor) nerve fibres
Where do the nerve fibres from the PNS emerge?
From brain and spinal cord and innervate every structure in the body
How many cranial nerves arise from the base of the brain?
What do these cranial nerves from the base of the brain innervate?
Head (including special sense organs)
Are cranial nerves specific?
Yes, some are purely sensory, some are purely motor
Where does the vagus nerve also innervate?
Some organs of the upper body e.g. heart
How many pairs of spinal nerves are there?
What do the spinal nerves innervate?
Remainder of the body
Where do afferent/sensory axons end?
Where do efferent/motor fibres end?
In effectors (muscle)
What are spinal nerves?
Elongation of the brain
What are spinal nerve dermatomes?
Skin areas innervated by a single spinal nerve
What do spinal nerves do before reaching the spinal cord?
Divide into Dorsal root and ventral root
What is the dorsal root?
Sensory (afferent) fibres (cell bodies= dorsal root ganglion)
What is the ventral root?
Motor (efferent) fibres (cell bodies= motonucleus)
What shape is the cross section of the spinal cord?
Butterfly shaped grey matter
What is the dorsal horn?
What is the ventral horn?
What is in the outer white matter?
Ascending and descending axons
What is the brain split into?
Brainstem and Forebrain
What is the Brainstem?
Most primitive part of the brain- vital function
Brain stem reticular formation e.g. arousal vs. sleep
What is the brainstem split into?
Hindbrain and midbrain
What makes up the hindbrain?
What makes up the midbrain?
What is the cerebellum?
Involved in motor control e.g. coordination and motor learning
What is the pons?
Largely white matter- connections between cortex and spinal cord, cortex and cerebellum
What is the medulla?
Relay nuclei for sensory pathways from spinal cord and cranial nerve and for descending pathways
Contains autonomic control centres
What is the tectum made up of?
Optic and auditory tectum
What is the optic tectum?
What is the auditory tectum?
What is the orientation reaction in the tectum?
Head and eye movements to foveate moving objects in peripheral visual field or look in direction of source of sound
What is the Forebrain?
Responsible for higher sensory, motor and cognitive functions
What makes up the forebrain?
What makes up the diencephalon?
Thalamus (relay nucleus)
What makes up the telencephalon?
What is the thalamus?
Group of sensory relay nuclei projecting to cortex
Pathways serving vision, audition, olfaction, taste and somatic
What is the hypothalamus?
Control of autonomic functions