Neurology Flashcards
What are the functions of the medulla oblongata
Vasomotor centre located here, controls a lot of autonomic life functions – heart rate, respiratory rate, blood pressure. The cardiovascular centre is here.
What are the functions of the pons?
Is latin for bridge, it is the bridge between the midbrain and the medulla. It relays signals between the midbrain and the medulla, which ultimately leads signals to the cerebral cortex.
What are the functions of the midbrain?
Involved in auditory signaling and relaying and has a role in eye movement.
What are the functions of the thalamus?
Part of the diencephalon. It is the final common pathway for sensory information, it is a sort of relay centre. It is not active whilst you are sleeping.
What are the functions of the hypothalamus?
Part of the diencephalon. Has a neural and portal system connecting it to the pituitary gland. It is a neuroendocrine organ and is in charge of a lot of homeostasis. It produces ADH and oxytocin which is then released from the posterior pituitary. It releases GnRH, Thyrotropin releasing hormone, Corticotropin releasing hormone, Growth hormone releasing hormone.
What are the functions of the pituitary gland?
Posterior pituitary releases Oxytocin and Vasopressin/ADH
Anterior pituitary releases prolactin, TSH, FSH, LH, Corticotropin hormone, GH
What are the functions of the cerebellum?
Unconscious proprioception, it is the executive centre for movement. It regulates your movement. Size matters here.
What are the functions of corpus callosum?
Connects the two cerebral hemispheres.
What are the functions of the ventricles?
Produce CSF
Part of the circulation system of the CSF, cushions the brain.
Within each ventricle is a choroid plexus that contains ependymal cells which produce CSF.
What are the functions of internal capsule?
Houses axons of motor neurons
Contains all the pathways that allow information to be transferred between the cerebral cortex and the spinal cord, brain stem and subcortical structures (thalamus etc.).
What are the functions of the limbic system?
Emotion, behaviour, motivation, long-term memory
What are the main lobes of the brain and what do they do at large?
Frontal lobe: site of primary motor cortex, site of higher thinking/cognition, involved in personality
Parietal lobe: site of primary sensory cortex, involved in processing sensory information regarding parts of the body as well as interpreting visual information, language and mathematics.
Temporal lobe: holds the primary auditory cortex, high level auditory processing
Occipital lobe: visual processing, contains the primary visual cortex
Where are the primary motor and sensory cortices?
Primary motor cortex: pre-central gyrus, in frontal lobe anterior to central sulcus.
Primary sensory cortex: post-central gyrus, in parietal lobe posterior to central sulcus.
Where are Wernicke’s and Broca’s areas? What sort of aphasia would result due to a lesion in each of these areas?
Broca’s aphasia is an expressive aphasia – can understand and interpret speech but cannot make words to reply.
Wernicke’s aphasia is a receptive aphasia – can talk fluently but make no sense, cannot make coherent replies
What branches of the circle of Willis mainly arise from the internal carotid arteries?
Middle cerebral arteries and Anterior cerebral arteries.
What branches of the circle of Willis mainly arise from the Vertebral arteries which then form the Basilar artery?
Posterior cerebral arteries
What arteries do vertebral arteries arise from?
Subclavian arteries
Blood from the superior saggital sinus, inferior sagittal sinus and great cerebral vein drain into the confluence of sinuses and then what major vein?
Internal jugular vein
Between what layers of the dura mater is the superior sagittal sinus?
The superior sagittal sinus is between the periosteal and meningeal layers of the dura mater
What sort of cellular junctions comprise the blood brain barrier?
Tight junctions
What is the name of the structures that make CSF?
Choroid plexuses
What are some of the main functions of CSF?
Protects, nourishes brain, removes metabolites, contains chemical messengers, it’s composition is similar to blood plasma, only that it has significantly less protein in it. High levels of protein in CSF can be indicative of infection.
Describe how CSF is circulated in the ventricular system.
CSF is produced in the choroid plexus(es)
It goes from the lateral ventricles to the 3rd ventricle via the interventricular foramen. From the 3rd ventricle it enters the 4th ventricle via the cerebral aqueduct. From the 4th ventricle it enters the subarachnoid space via the central canal, from the subarachnoid space it enters the venous system via subarachnoid granulations in the superior sagittal sinus.
What are the two cranial nerves that originate in the cerebrum?
Olfactory and optic nerves originate in the cerebrum.
What are the two cranial nerves that originate in the midbrain?
Oculomotor and trochlear nerves originate in the midbrain.
What are the four cranial nerves that originate in the pons?
Trigeminal, Abducens, Facial and Vestibulocochlear nerves originate in the pons.
What are the four cranial nerves that originate in the medulla?
Glossopharyngeal, Vagus, Accessory and hypoglossal originate in the medulla.
What are the two cranial nerves that are purely sensory?
The olfactory and optic cranial nerves are the only two cranial nerves that are purely sensory in function.
How does the superior oblique muscle move the eye?
The superior oblique moves the eye downwards and internally rotates it. A palsy to the trochlear nerve which innervates the superior oblique muscle would lead to an upwards and outwards facing eye.
What would a palsy in the 6th cranial nerve look like?
The 6th cranial nerve is the abducens nerve which innervates the lateral rectus muscle, which abducts the eye away from the midline. A palsy in the 6th cranial nerve would therefore result in an eye that is unable to be abducted past the midline.
SO4LR6
What are the 3 sensory branches of the trigeminal nerve called? (the dermatomes on the face) What motor function does the trigeminal nerve fulfill?
Opthalmic, Maxillary and Mandibular branches. It innervates the muscles of mastication.
Describe the motor, sensory and taste innervation of the tongue.
Motor: all motor innervation of the lingual muscles is by the hypoglossal (CN XII) nerve, apart from the palatoglossus muscle which receives vagal innervation (CN X).
Sensory and taste to the posterior 1/3 of the tongue is by the glossopharyngeal nerve (CN IX).
Sensation to the anterior 2/3 of the tongue is by the lingual branch of the trigeminal nerve (CN V).
Taste to the anterior 2/3 of the tongue is by the lingual branch of the facial (VII).
At what vertebral level does the spinal cord end and what does it form at this point?
Spinal cord ends at L1-L2 vertebral level and forms the conus medullaris, then the cauda equina.
There are two enlargements of the spinal cord, what are these enlargements called and what arises at these enlargements?
Cervical and lumbar enlargements. The brachial plexus arises at the cervical enlargement and the sacral and lumbar plexi arise at the lumbar enlargement.