The Nervous System Flashcards
What functions are carried out by the parietal lobe of the brain?
Integration of sensory afferents
Discrimination between different types of stimuli and localising intensity of stimulus
Involved in the ability to manipulate objects in space
Which anatomical structure demarcates the boundary between the frontal and parietal lobes?
The central sulcus
What are the functions of the occipital lobe of the brain?
Primary visual cortex
Dreams are developed and processed
What functions are undertaken by the temporal lobe of the Brain?
Responsible for hearing and interpretation of speech and hearing
What are the functions of the cerebellum of the brain?
Associated with movements that are grouped for the performance of selective responses requiring specific adjustments.
Maintains posture and muscle tone
What comprises the brainstem?
Midbrain
Pons
Medulla oblongata
What are the functions of the brainstem?
It is a relay tract area for the motor and sensory systems.
Cranial nerves arise here to supply motor and sensory innervation to the face and neck
Controls cardio-respiratory systems
How many cervical vertebrae are there?
7
How many thoracic vertebrae are there?
12
How many lumbar vertebrae are there?
5
How many sacral vertebrae are there?
5 fused vertebrae
How many bones make up the coccyx?
3-5
What is the fluid called that circulates around the brain and spinal cord?
Cerebrospinal fluid (CSF)
What information passes through the dorsal root of the spinal nerve?
Sensory afferent fibres of spinal nerves
What information passes through the ventral root of the spinal nerve?
Motor efferent fibres leaving from the ventral grey horn
What is the white matter of the spinal cord primarily composed of?
Myelinated axons
What is the grey matter of the spinal cord primarily composed of?
Unmyelinated neurons and supporting glia
What is contained in the dorsal root ganglion?
It is composed of the cell bodies of afferent neurons
What is a nerve plexus?
A collection of nerves that supply specific body regions
What does the brachial plexus supply?
Motor and sensory innervation to the upper limbs
What is the spinal origin of the brachial plexus?
C5-T1
Does the brachial plexus form part of the central or peripheral nervous system?
PNS
What is a dermatome?
A dermatome is a unilateral area of skin innervated by the sensory nerve fibres if a single spinal nerve
In total, how many spinal nerves are there?
31 pairs
What is the clinical significance of the dermatomes?
They can give an indication of the level of spinal cord where damage may be. A lesion of just a single spinal nerve however would rarely give numbness over that area due to overlap of innervation?
How many pairs of cranial nerves are there?
12
Do the cranial nerves form part of the CNS or PNS?
PNS
Where do cranial nerves arise from?
Brain and brain stem
Generally, what do the cranial nerves supply?
Head and neck structures as well as the gut, heart and respiratory system
Is the brain a part of the CNS or PNS?
CNS
Is the spinal cord part of the CNS or PNS?
CNS
What is the function of myelin?
Electrical insulation to allow faster conduction along a nerve
Which cells form myelin in the PNS?
Schwann cells
What is contained in the lateral ventricles of the brain?
Cerebrospinal fluid
What two major blood vessels provide the blood supply to the brain?
Internal carotid arteries and vertebral arteries
Where does venous blood from the brain drain to?
Internal jugular veins
From what vertebral levels does the sympathetic nervous system arise?
T1-L2
What are the origins of the parasympathetic nervous system?
Cranial nerves 3,7,9 and 10
S2-4
What is the cauda equina?
The lower end of the spinal cord that terminates as nerve roots
In an adult, at what level will the spinal cord terminate?
L2
What is the clinical relevance of knowing where the spinal cord terminates?
A sample of cerebrospinal fluid can be taken after the cord terminates.
What is the function of the corpus callosum?
Communication between the left and right hemispheres
What is the function of the thalamus?
It is the relay centre for motor and sensory fibres
What is the function of the hypothalamus?
To maintain homeostasis
What are the functions of the nervous system?
Communication Regulating internal events Organising behaviour Information storage (memory) Sensations, perceptions, emotions
What are the two main types of cell in the nervous system?
Neurons
Glia cells
What is myelin and where does it come from?
Myelin is a fatty tissue and is an outgrowth of glial cells
What kinds of cells form myelin in the PNS?
Schwann cells
What kinds of cells form myelin in the CNS?
Oligodendrocytes
What is the purpose of a myelin sheath around a neuron?
The sheath is electrically insulating so allows the effect to travel the length of the neuron more quickly
Astrocytes are a type of glial cells. What do they do?
Involved in nutrient supply to the CMS join to blood vessels on one side and neurons on the other to perform this function
Microglia are a type of glial cells. What do they do?
They have a role on phagocytic defence
Epedymal cells are a type of glial cells. What do they do?
Involved in the production of many substances such as cerebrospinal fluid which cushions and protects the brain
What part of the neuron receives information?
The dendrite
What is the name of the little notches on the myelin sheaths which allow for faster transmission of nerve signals?
Nodes of Ranvier
How do somatic nerves differ structurally from visceral nerves?
Somatic nerves are continuous whereas visceral nerves have two nerves on exit
What brain structures comprise the forebrain?
The cerebrum (telencephalon) and the thalamus and hypothalamus (diencephalon)
What structures comprise the midbrain or mesencephalon?
Pons
Medulla oblongata
Cerbellum
The brainstem is included in which part of the brain?
Hindbrain or rhombencephalon
What is the function of the frontal lobe of the brain?
Executive functions
Longterm memory
What is the function of the parietal lobe of the brain?
Integration of sensory functions
What is the function of the occipital lobe of the brain?
Visual processing
What is the function of the temporal lobe of the brain?
Auditory processing
In the spinal cord, sensory nerves travel at the ventral end and motor nerves travel at the dorsal end. T/F?
False - sensory nerves are dorsal
Motor nerves are ventral
Where are the cell bodies of primary sensory neurons contained?
Dorsal root ganglia
How many cervical spinal nerves are there?
8
How many thoracic spinal nerves are there?
12
How many lumbar spinal nerves are there?
5
How many sacral spinal nerves are there?
5
How many coccygeal spinal nerves are there?
1-3
Name the first three cranial nerves?
Olfactory
Optic
Oculomotor
Name the fourth, fifth and sixth cranial nerves.
Trochlear
Teigeminal
Abducens
Name the seventh, eighth and ninth cranial nerves.
Facial
Vestobulocochlear
Glossopharyngeal
Name the tenth, eleventh and twelfth cranial nerves?
Vagus
Spinal accessory
Hypoglossal
What are the basic functions of the sympathetic nervous system as opposed to the parasympathetic nervous system?
Sympathetic - flight or fight response
Parasympathetic - rest and digest
What would be the signs of damage to the afferent pathway of a tendon reflex?
Loss of reflex and associated sensory loss
What would be the signs of damage to the efferent pathway of a tendon reflex?
Loss of reflex and muscle paralysis
What is a myotome?
A group of muscles supplied by a specific spinal root
What are the effects on tone, power and reflexes of a lower motor neurone lesion?
Decreased tone
Decreased power
Hyporeflexia
What are the effects on tone, power and reflexes of an upper motor neurone lesion?
Increased tone
Decreased power
Hyperreflexia
