MRCS neuroanatomy Flashcards
where do the neurons of the corticobulbar tract terminate ?
The neurones terminate on the motor nuclei of the cranial nerves. Here, they synapse with lower motor neurones, which carry the motor signals to the muscles of the face and neck.
First order neurons carry signals from where to where in the DCML pathway ?
From the peripheral nervous system to the medulla oblongata
Which branch of the trigeminal nerve provides sensory innervation to the lower eyelid?
Maxillary
Which developmental component of the central nervous system is the substantia nigra located within?
Midbrain
how does the hypothalamus send neurotransmitters to the pituitary gland ?
hypophyseal portal vessels.
what two hormones are released by the posterior pituitary gland ?
ADH (responsible for control of blood osmolarity), and oxytocin (involved in parturition and milk secretion).
what is the function of the choroid plexus ?
production of CSF
The medial reticulospinal tract arises from what part of the brainstem ?
Pons
what structure separates the cerebrum from the cerebelli ?
tentorium cerebelli,
what lobe of the cerebrum is the primary auditory cortex located ?
Temporal lobe
True or false
The vestibulocochlear nerve has motor function
False
It is purely sensory
The vagus nerve provides motor innervation to what structures ?
- Pharynx
- Larynx
- Soft palate
what symptoms occur following Injury to the anterolateral system ?
impairment of pain and temperature sensation - this sensory loss will be contralateral
the middle cerebral arteries are a continuation of what artery ?
The internal carotid artery
what nerve supplies general sensory innervation and special taste sensation to the posterior 1/3rd of the tongue ?
the glossopharyngeal nerve.
what are the terminal branches of V1 ?
V1 - ophthalmic nerve
Branches
1. Frontal
2. Lacrimal
3. Nasocialliary.
List the sensory branches of CN IX
PLT
Pharyngeal branch - It innervates the mucosa of the oropharynx.
Lingual branch – provides the posterior 1/3 of the tongue with general and taste sensation
Tonsillar branch – innervates the palatine tonsils.
Vertebral arteries arise from which artery ?
Subclavian
The trigeminal nerve provides innervation to muscles from which pharyngeal arch?
First
what are the two types of ascending tracts ?
conscious tracts and unconscious tracts
define fasciculus
bundle - could be of nerves or muscles
what is the function of the corpus collosum
white matter structure connecting the two hemispheres.
In a stroke that damages the UMNs for CN XII - what would be the clinical signs ?
a lesion to the upper motor neurones for CN XII will result in spastic paralysis of the contralateral genioglossus.
This will result in the deviation of the tongue to the contralateral side.
what is the first motor branch of the facial nerve ?
nerve to stapedius.
how does the vestibulocochlear nerve exit the cranium ?
Via the internal acoustic meatus
Which part of the ear does the glossopharyngeal nerve innervate ?
The tympanic branch of the glossopharyngeal nerve innervates the middle ear, internal surface of the tympanic membrane and the Eustachian tube.
Prolactin is under tonic inhibition by what hormone ?
DOPAMINE
At what level does the spinal cord terminate in adults ?
L1 - L2
How does an abducens nerve palsy present ?
The eye held in fixed adduction at rest
what symptoms would occur following damage to the DCML pathway in the spinal cord ?
Ispilateral loss of proprioception and fine touch.
This is the course of what cranial nerve ? and what muscle does it pierce ?
Hint - crosses the internal and external carotid
- Hypoglossal nerve
- pierces the genioglossus
The parasympathetic fibres of the facial nerve are carried by what nerves ?
- Greater petrosal nerve
- Chorda tympanii
Which white matter tract is located immediately lateral to the putamen?
External capsule
what is the ansa cervicalis ?
a loop of nerves that is part of the cervical plexus. From the ansa cervicalis, nerves arise to innervate the omohyoid, sternohyoid and sternothyroid muscles - the infra hyoid muscles
The corticobulbar tracts provide innervation to the musculature of which region of the body?
Head and neck
what structure is both inferior and anterior to the pituitary gland
Sphenoid sinus
which nerves are involved in the corneal reflex ?
the ophthalmic nerve acts as the afferent limb
The facial nerve is the efferent limb,
what is the anatomical course of the right vagus nerve ?
passes anterior to the subclavian artery and posterior to the sternoclavicular joint, entering the thorax.
which cranial nerve innervates the stylopharyngeus ?
glossopharyngeal nerve
what is the function of the ventricles ?
production, transport and removal of cerebrospinal fluid, which bathes the central nervous system.
what are the functions of the temporal lobe ?
Memory and language
In the basal ganglia, what structures from the Neostriatum ?
Caudate nucleus and putamen
Before the facial nerve terminates as the 5 terminal motor branches, there are three motor branches - what are these ?
- Posterior auricular nerve
- nerve to digatrsric
- nerve to stylohyoid
describe Brown-Séquard syndrome
hemisection (one sided lesion) of the spinal cord. This is most often due to traumatic injury, and involves both the anterolateral system and the DCML pathway:
DCML pathway – ipsilateral loss of touch, vibration and proprioception.
Anterolateral system – contralateral loss of pain and temperature sensation.
It will also involve the descending motor tracts, causing an ipsilateral hemiparesis.
List the input nuclei of the basal ganglia
- Caudate nucleus
- Putamen
what is the primary (lemniscal pathway)
this is the main pathway through which auditory information reaches the primary auditory cortex (A1).
What hormone stimulated prolactin release ?
Thyrotrophin releasing hormone
what are the nuclei in the thalamus that receive signals from the optic nerve ?
lateral geniculate nucleus (LGN)
The oculomotor nerve provides motor and __________ innervation to the eye muscles.
parasympathetic
which nerve forms the oesophageal plexus ?
The vagal trunk which is a branch of the vagus nerve