Neuro Part 1 (Gross Structure of Brain, Spinal Cord, and Vasculature of the CNS)

kdw750's version from 2015-07-26 21:41

Frontal Lobe (Lecture 3)

Question Answer
primary motor cortexprecise individual muscle contractions in the performance of movement, located in the precentral gyrus and the anterior paracentral lobule
prefrontal cortexreactions to present situation based on past experiences, planning and execution, judgment, responsibility, personality and emotion, located on the remaining frontal cortex
premotor cortexpreperation for movement (postural adjustments in the proximal limb musculature), located in the posterior frontal gyri
supplemental motor cortexorganize or plan the sequence for muscle activation, located on the medial superior frontal gyrus
frontal eye fieldsvoluntary conjugate eye movements, anterior to the premotor cortex
motor speech areainvolved with the generation of proper pattern of signals to the speech musculature for meaningful speech, located in the opercular and triangular portions of the inferior frontal gyrus

Parietal Lobe (Lecture 3)

Question Answer
primary somatosensory cortexdiscrimination and localization of somatosensory info (conscious propioception discriminative touch, pressure, pain and temp), recognition for size, shape and texture of objects, located in the precentral gyrus and posterior paracentral lobule
secondary somatosensory cortexless discrimitatve aspects of the somatosensory info
somatosensory association cortextouch localization, memory of the somatic environment and spatial awareness, stereogenesis, graphesthesia, located in superior parietal lobule and precuneus
language arealanguage comprehension, interpretation, integration and formulation of language, located in supramarginal and angular gyri

Temporal Lobe (Lecture 3)

Question Answer
primary auditory cortexauditory reception, located in transverse temporal gyri
auditory association cortexinterpretation of auditory info like tones, loudness, sound modulation, timing as in music and recognition of sounds, located in superior temporal gyrus
wernicke's arealanguage comprehension like interpretation, integration and formulation of language, located in superior temporal gyrus
primary olfactory cortexreception of odors, located in uncus of parahippocampal gyrus
olfactory association cortexidentification of odors, located in uncus of parahippocampal gyrus

Occipital Lobe (Lecture 3)

Question Answer
primary visual cortexvisual reception, located in calcarine sulcus
visual association cortexrecognition of objects, perception of color and depth, and other complex aspects of vision, located above and below the primary visual cortex

Limbic Lobe (Lecture 3)

Question Answer
process sensoryinfo from the environment like sights, sounds, taste and smell, evokes feelings and emotions which promote survival and reproduction

Regions of the Brainstem

Question Answer
dorsal surface of the midbrainsuperior and inferior colliculus, CN 4
dorsal surface of the ponssuperior, middle, and inferior cerebellar peduncles, 4th ventrical, and facial colliculus
dorsal surface of the medulladorsal median sulcus, dorsal intermediate sulcus, dorsal lateral sulcus, fasiculus cuneatus, cuneate tubercle, 4th ventricle, and obex
ventral surface of the midbraincerebral peduncles, CN 3
ventral surface of the ponspontine protuberance, CN 5-8
ventral surface of the medullaantero median sulcus, antero lateral sulcus, pyramidal decussation, pyramids, CN 9-12, inferior olive, postolivary sulcus

Functional Components of Each Cranial Nerve (Lecture 6) (afferent = sensory/ carries, efferent = motor/ supplies)

Question Answer
SVEsupplies skeletal muscles of pharyngeal arch origin
GVEsupplies smooth muscles, cardiac muscles, and glands
GSEsupplies skeletal muscles of somatic origin
GSAcarries general somatic senses (touch, pain, temp, pressure)
GVAcarries general senses from viscera
SSAcarries special senses of vision, hearing, and equilibrium (eye and ear)
SVAcarries special senses of smell and taste (nose and tongue)

Symptoms of a Lesion of Each Cranial Nerve (Lecture 6)

Question Answer
SVELoss of motor to the muscles of mastication (muscles of facial expression)
GVELoss of parasympatheric innervation of the lacrimal, submandibular, and sublingual glands (glandular secretion)
GSALoss of sensory to the area around the external auditory meatus
SVALoss of taste to the anterior two-thirds of the tongue

Describe the internal anatomy of the spinal cord

Question Answer
internal anatomythe spinal cord has white mater on the outside with a butterfly shaped gray mater on the inside. The gray matter has a dorsal and ventral horn with different functions in each area, DAP (dura mater, arachnoid mater, and pia mater)

Draw a cross section of the spinal cord including the dorsal and ventral roots, spinal nerve, and the dorsal and ventral rami. Label all components of the white and gray

Describe the following

Question Answer
complete spinal cord transectionboth the ascending and descending pathways are severed. Sensory loss below level of injury, bilateral UMN weakness, possible LMN weakness at the level of lesion
hemicord section(brown sequard)common causes is penetrating injuries, MS and lateral compression from tumors. Damage to the corticospinal tract=ipsilateral UMN weakness. Interruption of posterior columns=ipsilateral loss of vibration and joint position sense. Interruption of anterolateral system=contralateral loss of pain and temp sensation (sensoy loss is often below level of lesion)
posterior cord syndromecommon causes includes trauma, extrinic compression from posteriorly located tumors, MS, vitamin B deficiency, and tabes dorsalis (slow degeneration of nerves in dorsal column). It is the interruption of posterior columns=vibration and joint postion sensory loss below level of lesion. ataxia gait. a larger lesion=lateral corticospinal tract
anterior cord syndromecommon causes includes trauma, MS, and anterior spinal artery infarct. Its damage is at the anterior horn=LMN deficit at level lower of lesion. Interruption of lateral corticospinal tract, anterolateral system, descending pathways controlling sphincter function
central cord lesioncan be a small or large lesion. common causes for a small lesion includes spinal cord contusion, post traumatic syringomyelia (rear ended in a car accident), and intrinsic spinal cord tumor. It has damage to spinothalmic fibers crossing in anterior commisure, Interruption of one or more adjacent bilateral = classic cape distribution. A large lesion is commonly caused by spinal cord loss of pain and temp sense. lesions of lower cervical or upper thoracic cord is called thecontusion, post traumatic syringomelia, and intrinisic spinal cord tumor. It has damage to the anterior horn cells=LMN deficits at level of lesion. Interruptions of lateral corticospinal tract=UMN signs, interruptions of posterior columns=loss of vibration and joint position sense, compression of anterolateral system from medial surface=complete pain and temp loss below lesion (sacral sparing

Differences between a radiculopathy and a peripheral neuropathy

Question Answer
Radiculopathy locationinvolved with the spinal root so it can be either motor or sensory issue depending on the root.
Radiculopathy symptomssharp or chronic pain, sensory or motor loss, weakness, and diminished reflexes. Pain radiates down the dermatome of the affected nerve root. for example if the posterior root is involved then pain and sensory loss in the distribution of the posterior root. If the anterior root is involved then weakness in the muscles innervated by the anterior root and possible reflex involvement. If the spinal nerve is involved then both motor and sensory is involved
Radiculopathy causespressure on the spinal cord, intervertebral disc disease can cause herniation and spondylolyis. This cause lack of blood supply and compression to the spinal root. Trauma, diabetes, epidural metastases, nerve sheath tumors and herpes zoster also can cause radiculopathy
Radiculopathy typesherniation of L4-L5 disc impinges on L5 (inferior #)
Peripheral neuropathy locationis a spinal nerve or rami disorder so it is both sensory and motor loss. It involves the axon or myelin or both. Spinal nerves either directly from peripheral nerves or combine to form peripheral nerves. They contain GSA,GSE, and GVE
Peripheral neuropathy symptomsweakness and sensory loss in a single or multiple peripheral nerves. It would show variable autonomic signs. diminished reflexes. common in diabetics
Peripheral neuropathy causescan be caused by extrinsic compression like a cast or laceration. It can be caused intrinsically from entrapment of bone or connective tissues
Peripheral neuropathy typesmononeuropathy (femoral, sciatic, fibular, radial, median, ulnar, axillary) diabetic peripheral neuropathy-due to compromised vascular supply. symptoms include painless parethesiase beginning in feet and lower legs, impairment of propioception, diminished reflexes, burning sensations in the feet. Loss of sensation in the feet means that sores or injuries may go unnoticed and may become ulcerated

Describe the vertebral arteries and the structures they vascularize

Question Answer
vertebral arteriesarise from the subclavian artery. the vertebral a. and the internal carotid arteries are the two sources of blood to the brain. The vertebral artery courses through the transverse foramen’s of upper 6 cervical vertebrae, through the foramen magnum and then give off branches before continuing on as basilar artery
4 major branches of the vertebral arteryPosterior inferior cerebellar artery (PICA), posterior and anterior spinal artery, and medullary artery.
posterior inferior cerebellar arterysupplies blood to inferior surface of the cerebellum and part of medulla. It gives rise to the posterior spinal artery
posterior spinal arteryvascularizes part of the spinal cord.
anterior spinal arterysupplies blood to the other part of the spinal cord.
medullary arteryvascularirzes part of the medulla

Describe the internal carotid arteries and the structures they vascularize

Question Answer
internal carotid arteriesbranch off the common carotid a, it ascends in the superior portion of the neck. It goes through the carotid canals, cavernosus sinus, pierces the dura mater and enters the middle cranial fossa next to the sella turcia, where it divides into middle and anterior cerebral a., the other branch it gives off is the posterior communication branches which is an anastomotic connection between the internal carotid a and poster cerebral a.
middle cerebral arterysupplies the lateral surface of frontal, parietal, temporal, and occipital lobe
anterior cerebral arterysupplies the medial surface of the frontal and parietal lobes

Describe the vasculature supply to the spinal cord

Question Answer
vasculature supply of the spinal cordcomes from the anterior and posterior spinal arteries
anterior spinal arteriessupplies blood to the anterior white column, central portion of the lateral column, and most of the gray matter except for the tips of the posterior horn.
posterior spinal arteriessupplies blood to posterior white columns, peripheral portion of the lateral columns, and the tips of the dorsal horns