A&p Chapter 14 Brain And Cranial Nerves

Front 1

What are anatomical terms for the “folds” and “valleys” of the cerebral cortex?

Back 1

Gyri=folds. Sulci=grooves. Longitudinal fissure separates cerebral hemispheres. Cortex is the surface layer of gray matter. Nuclei is deeper masses of gray matter. Tracts are bundles of axons, white matter.

Front 2

What are the different lobes of the cerebral

cortex, and what some basic functionsascribed to each?

Back 2

i. Frontal: voluntary motor functions, planning,

mood, smell, and social judgement.

ii. Parietal: receives and integrates sensory

information.

iii. Temporal: areas for hearing, smelling,

learning, memory, emotional behavior.

iv. Occipital: visual center of the brains

Front 3

Discuss brain injuries and the typical deficits found with injury to parietal lobes?

Back 3

Parietal Lobe injuries: right hemisphere causes contralateral neglect syndrome, and left hemisphere (dominant hemisphere in 95% of people) causes Wernicke’s aphasia which is problems with comprehension of spoken language.

Front 4

Discuss brain injuries and the typical deficits found with injury to temporal?

Back 4

Temporal lobe injuries (inferior occipitotemporal cortex): inability torecognize objects (agnosia) and inability to recognize faces (prosopagnosia)

Front 5

Discuss brain injuries and the typical deficits found with injury to frontal?

Back 5

Problems with personality, inability to plan and execute appropriate behavior.

Front 6

Discuss brain injuries and the typical deficits found with injury to occipital lobes?

Back 6

Issues with vision

Front 7

What brain regions are associated with emotions and reward?

Back 7

The prefrontral cortex controls expression of emotions. Form in hypothalamus and amygdala (fear, anger, pleasure, love, etc.),and behavior is often learned by rewards and punishments or responses ofothers.

Front 8

What functions will be abnormal with damage to the hippocampus?

Back 8

It is important for memory. Damage to the hippocampus can cause aninability to acquire new memories and may cause problems with retrieving old memories. Acetylcholine is an importantneurotransmitter in the hippocampus.

Front 9

What type of memory deficit first presents in patients with Alzheimer’s disease and what are the classic pathological findings of Alzheimer’s brains upon autopsy (grossly and histologically)? What neurotransmitter is affected during life?

Back 9

Early stages show memory loss for recent events. Some of the findings from pathophysiology iscerebral atrophy, neuronal noss in areas that connect with the hippocampus,cholinergic neurons are lost. A drug,Aricept (donepezil), is a cholinesterase inhibitor (doesn’t cure thedisease). Beta amyloid plaques and neurofibrillary tangles.

Front 10

What are the main functions of the basal

ganglia?

Back 10

The basal ganglia are deep nuclei in the cerebralhemispheres. Their main function is to influence motor activity by modulating the cerebral cortex, influences cognitive and emotional functions. Basalganglia pathology manifests primarily as motor dysfunction.

Front 11

What type of tremor is associated with Parkinson’s disease?

Back 11

Resting tremor: 4 to 6 hertz and often pill rolling

Front 12

What movement characteristics are present in Parkinson's other than resting tremor?

Back 12

*Bradykinesis: slowness of movements and difficulty initiating movements

*Rigidity: cogwheel type

*Gait instability: festinating gait with trouble starting and stopping

*Masked face: smooth and expressionless

Front 13

What basic drug treatment is offered to patient’s with Parkinson’s disease. What neurotransmitter is decreased in this pathology?

Back 13

Parkinson’s disease is a loss of dopamine that decreases thalamocortical excitation.

Pharmacological treatment with L-dopa which crosses the BBB

Front 14

Loss of pigmentation in the substantia nigra is indicative of what disease process?

Back 14

It is indicative of a loss of dopaminergic neurons—related to Parkinson’s.

Front 15

What main function does the thalamus perform?

Back 15

The thalamus is the oval mass of gray matter that protrudes into lateral ventricle and 3rd ventricle of the brain. It serves as a sensory relay region receiving nearly all sensory information on its way to cerebral cortex,except olfactory (smell), relays signals from cerebellum to motor cortex.

Front 16

Which sense does not project through the

thalamus on way to the cortex?

Back 16

Olfactory (smell)

Front 17

Where is the hypothalamus and what are the

basic functions associated with this region of the brain?

Back 17

The hypothalamus is in the walls and floor of the 3rd ventricle. Its functions are hormone secretion,autonomic NS control, thermoregulation, food and water intake (hunger andsatiety), sleep and circadian rhythms, memory (mammillary bodies), and emotional behavior.

Front 18

Where is the medulla oblongata located and what are it most important functions?

Back 18

It is located below the midbrain and pons. There are four important functions. (1) Cardiac centeradjusts the rate and force of the heart, (2) vasomotor center adjusts bloodvessel diameter, (3) respiratory centers control rate and depth of breathing,and (4) reflex centers for coughing, sneezing, gagging, swallowing, vomiting,salivation, sweating, and movements of tongue and head.

Front 19

Where are the cardiac, vasomotor, respiratory centers of the brain located?

Back 19

In the medulla oblongata.

Front 20

What are the functions of the cerebellum?

Back 20

Evaluation of sensory input (coordination of locomotorability, spatial perception), time keeping center (predicting movement of objects), distinguish pitch and similar sounding words, and planning and scheduling tasks.

Front 21

What signs are present when the cerebellum is damaged?

Back 21

Cerebellar damage has ipsilateral consequences. Some signs are ataxia—uncoordinated, clumsygait. Dysmetria—abnormal overshoot or undershoot. Dysrhythmia—abnormal rhythm and timing of movements. Dysdiadochokinesia—patientcannot perform rapidly alternating movements.

Front 22

What is a stroke?

Back 22

A stroke or cerebrovascular accident (CVA) is thesudden death (infarction of brain tissue caused by ischemia). Cerebral ischemia can be produced by atherosclerosis, thrombosis, or a ruptured

aneurysm.

Front 23

Describe only to the detail presented in class the blood supply to the brain.

Back 23

The brain receives blood from vertebral arteries and internal carotid arteries. Problems arise when one or more of these vessels become occluded by atherosclerosis. Cardiologists monitor the carotid arteries by ultrasound.

Front 24

What results from a stroke?

Back 24

The effects of a CVA range from unnoticeable to fatal,depending on the extent of tissue damage and the function of the region of the brain that is damaged. Recovery dependson the ability of neighboring neurons to take over the lost function and on the extent of collateral circulation to the regions of the brain.

Front 25

Which side of the brain is likely affected in a stroke in which speech and language are affected?

Back 25

Middle cerebral artery strokes cause contralateralhemiplegia—paralysis on the opposite side. The dominant hemisphere strokes affect speech and language. In about 95% of people, regardless of handedness,the left hemisphere is dominant.

Front 26

What is left neglect and what side of the brain is affected?

Back 26

The non-dominant hemisphere stroke causes neglectsyndrome—usually left neglect. Some

forget the left side when performing daily

functions, shaving, eating, etc.

Front 27

What substances freely diffuse through the blood brain barrier?

Back 27

It is permeable to lipid soluble materials,

alcohol,oxygen, carbon dioxide, nicotine, and anesthetics.

Front 28

What affect does this barrier have on drug

delivery to the CNS?

Back 28

Diseases of the brain must be treated with drugs that can cross the blood brain barrier. For example, in Parkinson’s disease, a disease in which brain dopamine is reduced, treatment can’t be with dopamine because it can’t cross the BBB. They treat it with L-dopa which is a precursor that can cross the barrier.

Front 29

What and where is the dura mater?

Back 29

Outermost, tough membrane, outer periosteal layer against bone, where separated from inner meningeal layer forms dural venous sinuses draining blood from brain, supportive structures formed by dura mater(falx cerebri, falx cerebelli, and tentorium cerebelli, epidural space is filled with fat in the low back (epidural anesthesia during childbirth)

Front 30

What is meningitis?

Back 30

It is the inflammation of the meninges from bacterialor viral invasion of the CNS through the nose and throat. Signs include high fever, stiff neck,drowsiness, and intense headache. It can progress to coma. It can cause swelling of the brain, cerebral hemorrhaging, and sometimes death within hours of onset of symptoms. You diagnose it by examining the CSF by lumbar puncture (spinal tap). Treatments for bacterial are IV antibiotics.

Front 31

Which is typically more serious bacterial or viral meningitis?

Back 31

Viral usually resolves on its own unless it is

severe. The bacterial form is more serious.

Front 32

Describe an epidural bleed.

Back 32

The dura mater has its own blood supply (separate from the brain). An epidural hemorrhage isusually caused by trauma to the temple. Blood collects between the bone of the skull and the periosteal layer of dura. It slowly separates the periostealdura from the bone. It is an emergency situation. (Lens shaped accumulation of blood)

Front 33

Describe a subdural bleed.

Back 33

Blood from torn veins fills the potential space between the dura and the arachnoid mater. It typically occurs in older individuals because the brain is atrophied and has more space between the brain and the arachnoid—it puts strain on veins from the brain to dural venous sinuses. It is slow and insidious—it may be a trivial injury with or without loss of consciousness. (Crescent shaped hemorrhage)

Front 34

What tissue and cells produce cerebrospinal

fluid?

Back 34

CSF is produced by choroid plexus. CSF is a clear and colorless liquid that fills ventricles and subarachnoid space. The brain produces and absorbs about 500mL/day (choroid plexus creates by filtration of blood).

Front 35

What is the function of CSF and what are the consequences of obstruction to the flow of CSF?

Back 35

Some functions of CSF are it floats the brain so it is neutrally buoyant, cushions from hitting inside of skull, and chemical stability (rinses away wastes).

Front 36

Where is CSF normally reabsorbed back into the venous blood?

Back 36

It escapes through the 4th ventricle to surround the brain. It is absorbed into venous sinus by arachnoid villi.

Front 37

What are the functions ascribed to regions of the brain that lack a blood brain barrier? What is the downside to this blood brain barrier?

Back 37

The 3rd and 4th ventricles are breaks in the barrier where the blood has direct access. They monitor glucose, pH, osmolarity and is a route for HIV virus to invade the brain.

Front 38

What is the basic function associated with the olfactory nerve?

Back 38

Responsible for sense of smell, damage causes impaired sense of smell (anosmia), damage can come from occupational solvents like acetone.

Front 39

What is the basic function associated with the optic nerve?

Back 39

Provides vision, damage can cause blindness in visual field

Front 40

What is the basic function associated with the oculomotor nerve?

Back 40

Controls eye movement, opening of eyelid,

constriction of pupil, focusing—damage causes drooping eyelid (Ptosis), dilated pupil,double

vision, difficulty focusing and inability to move eye in certain directions

Front 41

What is the basic function associated with the trochlear nerve?

Back 41

It controls one muscle for eye movement (superior oblique muscle)—damage causes double

vision and inability to rotate eye inferolaterally

Front 42

What is the basic function associated with the tri-geminal nerve?

Back 42

Provides sensory innervation to face (touch, pain, andtemperature) and muscles of mastication—damage produces loss of sensation and impaired chewing.

Front 43

What is the basic function associated with the abducens nerve?

Back 43

Provides for eye movement via one muscle (lateralrectus muscle)—damage results in inability to gaze laterally

Front 44

Describe 3rd nerve palsy

Back 44

An injury to the oculomotor nerve causes affected eye to look down and out, unopposed action of the lateral rectus and superior obliquemuscles, eyelid closed on affected side, pupil is fixed and dilated.

Front 45

Describe 4th nerve palsy

Back 45

It is trochlear palsy. The affected eye looks upward when patient is asked to stare ahead. The patient suffers from diplopia. The patient tilts their head downward away from affected eye to compensate.

Front 46

What is tri-geminal neuralgia?

Back 46

(aka tic douloureux) It is the most common cranialneuralgia, characterized by attacks of excruciating pain over the distribution of one or more of the branches of the trigeminal nerve. Carbamazepine is regarded by most as the medical treatment of choice—it stabilizes inactivated sodium channels.

Front 47

What is 6th nerve palsy?

Back 47

Injury of the abducens nerve causes a lateral gaze deficit. In the top photo, the patientis looking straight ahead. In the bottom photo, they are looking to the right. Notice the right eye can’t move past the midline of the orbit.

Front 48

What is the basic function associated with the

facial nerve?

Back 48

Innervates the muscles of facial expression, salivary glands and tear, nasal and palatine glands. It provides the sensory taste on anterior 2/3 of tongue. Damage produces a sagging of facial muscles and disturbed sense of taste.

Front 49

What is the basic function associated with vestibulocochlear nerve 8?

Back 49

Innervates structures that provide hearing and sense of balance—damage produces deafness, dizziness, nausea, loss of balance and nystagmus. Some pharmaceuticals are ototoxic (aspirin and some antibiotics)—they irreparably damage hair cells in the cochlea (organ in the inner ear for hearing).

Front 50

What is the basic function associated with

glossopharyngeal nerve?

Back 50

Controls swallowing, salivation, gagging, control of BP and respiration, sensations from posterior 1/3 of tongue, and damage results in loss of bitter and sour taste and impaired swallowing.

Front 51

What is the basic function associated with vagus nerve?

Back 51

Swallowing, speech, regulation of viscera, slows heartrate, promotes peristalsis of gut, damage causes hoarseness or loss of voice,impaired swallowing and fatal if both are cut

Front 52

What is the basic function associated with

accessory nerve 11?

Back 52

It innervates two muscles that control the head, neck,and shoulder movement—damage causes impaired head, neck, shoulder movement, andhead will turn towards the injured side

Front 53

What is Bell's palsy?

Back 53

The most common facial nerve disorder,

spontaneous onset over hours or days, gradual recovery usually follows, it has an unknowncause (possibly viral or inflammatory), about 80% of patients recover in 3 weeks, treatments include corticosteroid anti-inflammatory drugs, often the oral anti-viral drug acyclovir is used, but has little evidence of efficacy.

Front 54

What is acoustic neuroma or acoustic

schwannoma?

Back 54

Cerebellopontine angle, slow growth over years, it is benign but occupies space, tinnitus (ringing in ears), hearing loss and vertigo, but may cause facial paralysis due to compression of facialnerve.

Front 55

What is deviation of uvula?

Back 55

When there is an injury to cranial nerve X, on examination of the oral cavity, the uvula will

deviate to the opposite (normal)side. Also, the palatoglossus muscle elevates the lateral margin of the tongue, but it won’t contract on the affected side.

Front 56

What is spinal accessory nerve innervation of trapezius?

Back 56

Damage to central nerve 11 may cause trapezius muscle atrophy and shoulder droop

Front 57

What is the basic function of hypoglossal nerve 12?

Back 57

Controls the tongue movements for speech, food manipulation and swallowing—if both are damaged, you can’t protrude tongue—if one side is damaged, the tongue deviates towards the injured side (ipsilateralatrophy).

Front 58

What is hypoglossal nerve injury?

Back 58

Due to actions of the tongue muscles, an injury tothis nerve causes the protruded tongue to point toward the side of the nerve damage

Front 59

Which cranial nerves have parasympathetic fibers associated with them?

Back 59

Oculomotor, facial, glossopharyngeal, and vagus nerves. These fibers carry special sensory input fromthe eye for vision and from the ear for

hearing.