Anatomy of the Cranial Nerves and Nuclei Flashcards
Label the inferior view of the Cranial Nerves
Label the anterior view of the brainstem
Label the posterior view of the brainstem
Where is the Olfactory Nerve located and where is its nucleus?
At what level of the brain are the following cranial nerves located?
III Oculomotor
IV Trochlear
VI Abducens
XII Hypoglossal
Label the diagram for the Oculomotor centres
Edinger-Westphal Nucleus (pregnaglionic parasympathetic nucleus)
Oculomotor nucleus (somatic motor nucleus)
Identify the Nuclei of the Oculomotor Nerve
ORANGE
Edinger-Westphal Nucleus (pregnaglionic parasympathetic nucleus)
RED
Oculomotor nucleus (somatic motor nucleus)
Label the diagram for the Tochlear nucleus
Identify the Trochlear Nucleus
Label the Abducens Nucleus
Identify the Abducens Nucleus
Label the diagram of the hypoglossal nucleus
Identify the hypoglossal Nucleus
Label these Cranial Nerves
Label the diagram of the Spinal Accessory Nerve
List the Functions of the Trigeminal Nerve
Functions:
- Somatosensation of face: discriminative touch, vibration sense, pain, temperature
- Proprioception associated with chewing (TMJ, muscles of mastication, teeth
- Motor control: muscles of mastication, tensor tympani, mylohyoid, ant. belly of digastric, tensor veli palatini
Label the diagram of the Trigeminal Sensory Nuclei
Describe the Trigeminal Nucleus and its parts
The sensory nucleus of the trigeminal forms a long column of neurons that stretches from the midbrain down to the upper 2 segments of the cervical spinal cord. It has 3 parts, separated by function.
What is the function of the Mesencephalic Nucleus?
Trigeminal Nerve Proprioceptive information from teeth and jaw arrive at the mesencephalic nucleus. Proximity to motor nucleus offers obvious advantages in terms of jaw reflexes.
The mesencephalic nucleus is very unusual, it is the only site in the CNS where the cell bodies of the primary afferent neurons live inside the CNS. It is essentially a ‘retained’ sensory ganglion.
What is the function of the Pontine Trigeminal Nucleus (Principal Nucleus)
Trigemnial Nerve discriminitive touch & vibration
What is the function of the Spinal Nucleus?
Trigeminal Nerve Pain and Temperature
Identify Trigeminal Nerve Nuclei
Describe the function of the Facial nerve
- Motor (muscles of facial expression, stapedius).
- Parasymp. innervation to pterygopalatine and submandibular ganglia.
- Taste (anterior 2/3 of tongue via c. tympani).
Describe the function of the Glossopharyngeal nerve
- Tactile sense, pain and temperature sense from the posterior tongue pharyngotympanic tube and upper pharynx.
- Taste (posterior 1/3 of the tongue).
- Parasympathetic fibres to the otic ganglion (parotid gland).
- Motor (one muscle: stylopharyngeus)
Describe the function of the Vagus Nerve
- Tactile sense, pain and temperature sense from the pharynx, larynx, trachea, oesophagus and thoracic and abdominal viscera.
- Taste (epiglottis)
- Parasympathetic innervation to ganglia serving thoracic and abdominal viscera.
- Motor (striated muscle of the pharynx and larynx) (cranial accessory contributes to this function).
Label the diagram of the Facial Nerve Nuclei
Label diagram of the Glossopharyngeal Nuclei
Label the component of the Vagus nerve nuclei
What is the function of the Solitary Nucleus?
CNs VII, IX, X
taste and visceral sensory information
What is the functio of the Superior and Inferior Salivatory nuclei?
CN VII and IX
parasympathetic efferents to ganglia of salivary glands and pterygopalatine ganglion
What is the function of Nucleus Ambiguus?
CN’s IX and X (and cranial part of XI)
motor efferents to muscles of pharynx, larynx and upper oesophagus
Label the diagram of the Solitary Nucleus
Identify the location of the solitary Nucleus on the sections
Identify the Location of Nucleus Ambiguus
Lower Pons / Upper Medulla
What is the corticobulbar tract?
The corticobulbar tract is the part of the pyramidal tract that is motor to cranial nerves.
This includes fibres to the motor nuclei of CN’s V, VII, X, and XII.
Label the diagram of the corticobulbar tract
What is the reticular formation?
The reticular formation is a network of loosely aggregated cells with cell bodies, axons and dendrites intermingling in the central core of the brainstem. It is distinct from the long pathways (like
the medial lemniscus, or the corticospinal tract)
and the specific distinct cell groups (like cranial nerve nuclei).
What is the function of the reticular formation?
The reticular formation includes centres that:
- Integrate cranial nerve reflexes.
- Participate in conduction and modulation of pain.
- Influence voluntary movement.
- Regulate autonomic activity.
- Integrate some basic functions, like respiration and
sleep.
•Activate the cerebral cortex: major component of the Ascending Reticular Activating System (a medial bilateral lesion of the brainstem reticular formation at or above the upper pons causes irreversible coma).
