Cranial nerves and chapters 10 and 11 exam

What are the cranial nerves?

Twelve pairs of nerves that supply the head, neck, and shoulders.

What is the function of the Olfactory nerve (CN I)?

It carries sensory information related to smell from the nose to the temporal lobe.

What happens if the Olfactory nerve is damaged?

It may cause loss of the sense of smell (anosmia) and loss of taste.

What type of information does the Optic nerve (CN II) carry?

Visual information from the eye to the primary visual cortex of the occipital lobe.

What happens if the Optic nerve is damaged?

It can cause diminished vision or blindness in the affected eye.

What is the main role of the Oculomotor nerve (CN III)?

It controls most movements of the eyeball, eyelid, and pupil size.

What are possible effects of damage to the Oculomotor nerve?

It may affect pupillary response, cause ptosis, and might dilate and fix pupils under severe compression.

What does the Trochlear nerve (CN IV) assist with?

It helps with the movement of the eyeball by innervating an extrinsic eye muscle.

What can damage to the Trochlear nerve lead to?

Inability to rotate the eye properly or double vision.

What is the function of the Trigeminal nerve (CN V)?

It has three branches that supply the facial region and innervate chewing muscles.

What are the symptoms of Trigeminal nerve damage?

Loss of sensation and impaired movement of the lower jaw, as well as severe facial pain called trigeminal neuralgia.

What does the Abducens nerve (CN VI) control?

It controls lateral eye movement by innervating one extrinsic eye muscle.

What happens if the Abducens nerve is damaged?

It prevents lateral rotation of the eye.

What is the role of the CN VII?

It controls facial expressions, stimulates saliva and tears, and provides taste sensations.

What condition is associated with Facial nerve damage?

Bell’s palsy, indicated by absence of facial expression on the affected side.

What type of information does the CN VIII carry?

It carries auditory and equilibrium information from the inner ear to the brain.

What are the effects of Vestibulocochlear nerve damage?

It can lead to loss of hearing or balance, and dizziness (vertigo) due to middle ear infection.

What does the Glossopharyngeal nerve (CN IX) handle?

It carries taste sensations from the posterior tongue and aids in swallowing.

What can occur if the Glossopharyngeal nerve is damaged?

Loss of the gag reflex, increasing the risk for choking.

What is the function of the Vagus nerve (CN X)?

It supplies structures in the tongue, pharynx, larynx, and many thoracic & abdominal organs.

What severe consequences can arise from Vagus nerve damage?

Hoarseness, impaired swallowing, diminished digestive motility, and potential fatality if both nerves are damaged.

What muscles does the Accessory nerve (CN XI) supply?

It supplies the sternocleidomastoid and trapezius muscles.

What is the effect of damage to the Accessory nerve?

It results in inability to shrug shoulders and rotate the head.

What does the Hypoglossal nerve (CN XII) control?

Movement of the tongue affecting speaking and swallowing.

What occurs when the Hypoglossal nerve is damaged?

The tongue deviates toward the injured side.

What are the two main types of sense organs?

Special sense organs and general sense organs.

What are the functions of general sense organs?

They are responsible for pain, temperature, touch, and pressure.

What type of receptors respond to painful stimuli?

Nociceptors.

What are proprioceptors responsible for?

They provide information about the position or movement of different body parts and changes in muscle length or tension.

What are the three triggers identified for pain?

Tissue injury, oxygen deficiency, and tissue deformation/stretching.

What is referred pain?

Pain felt as if it is coming from an area other than the actual site of origin, due to shared sensory nerve pathways.

What is the sclera?

The tough outer coat of the eye, also known as the 'white' of the eye.

What is the function of the cornea?

It is the transparent part of the sclera that focuses light and is known as the 'window' of the eye.

What are rods and cones?

Photoreceptors located in the retina; rods are responsible for night vision and cones for color vision.

What happens during a detached retina?

It is no longer nourished by the blood supplied by the choroid layer, which can lead to blindness.

What is a common consequence of excessive intraocular pressure?

Glaucoma, which can reduce blood flow to the retina and cause retinal degeneration.

What is presbyopia?

The decreased ability to focus on close objects due to loss of elasticity of the lens with age.

What are the sensory functions of the ear?

Hearing and equilibrium.

What is the role of the Eustachian tube?

It connects the middle ear with the throat and equalizes pressure across the tympanic membrane.

What are taste buds?

Chemoreceptors responsible for detecting taste sensations.

What is required for olfactory receptors to detect odors?

Odor-causing chemicals must be dissolved in the watery mucus lining the nasal cavity.

What is the photopupillary reflex?

The reflex that regulates the amount of light entering the eye by constricting or dilating the pupil.

What is the PERRLA assessment?

Pupils Equal, Round, Reactive to Light and Accommodation.

What visual disorder is caused by an irregularity of the cornea or lens?

Astigmatism.

What are the components of the inner ear involved in balance?

The vestibule and semicircular canals.

What are the two main divisions of the nervous system?

Central Nervous System (CNS) and Peripheral Nervous System (PNS).

What are the three functions of the nervous system?

Sensory, integrative, and motor functions.

What types of cells are found in the nervous system?

Neurons and glia.

What is the function of sensory neurons?

They conduct impulses to the spinal cord and brain.

What is the primary purpose of glia in the nervous system?

To support and protect neurons.

What characterizes multiple sclerosis?

Myelin loss in central nerve fibers, leading to communication disruption between the brain and body.

What is a reflex arc?

A neural pathway that controls a reflex action.

What is the role of neurotransmitters?

They allow communication between neurons.

Differentiate between myelinated and unmyelinated neurons.

Myelinated neurons are insulated with myelin, while unmyelinated neurons lack this insulation.

What is a synapse?

The junction where impulses are transmitted from one neuron to another.

What are autonomic nervous system divisions?

Sympathetic and parasympathetic divisions.

What occurs during the fight-or-flight response?

Increased heart rate, dilation of blood vessels in muscles, and reduced activity in non-essential functions.

What part of the brain is involved in muscle coordination?

The cerebellum.

What is hydrocephalus?

A condition caused by the accumulation of cerebrospinal fluid in the brain.

Describe the role of the thalamus in the brain.

It acts as a relay for sensory and motor signals to the cerebral cortex.

What are the major coverings of the central nervous system?

Dura mater, arachnoid mater, and pia mater.

What are three hearing disorders?

otosclerosis, otitis, and tinnitus

Explain otosclerosis?

abnormal bone growth in the middle ear which leads to hearing loss

Explain otitis?

inflammation of the middle ear causing pain and potential hearing loss

Explain tinnitus?

a condition with ringing in the ears

Explain presbycusis?

age related hearing loss due to changes in the inner ear and auditory nerve

what is the differences between tinnitus and meniere disease?

Tinnitus is ringing or buzzing in the ears while Meniere's disease are episodes of hearing loss, tinnitus, and vertigo due to inner ear abnormalities

Oligodendrocytes form myelin sheaths around _____ axons.

CNS (central nervous system)

PNS myelin is formed by what kind of cells?

Schwann cells

what is acetylcholine?

stimulates the muscles and transmits nerve signals

define catecholamines

are neurotransmitters that include dopamine, norepinephrine, and epinephrine, which are involved in regulating mood, sleep, and responses to stress.

What are endorphins?

the feel good chemical aka a natural pain relief

define nitric oxide

helps with blood vessel dilation and nerve signaling

What is Parkinson’s is caused by what?

low levels of dopamine in the motor control areas

what is bradykinesia and what is it a symptom of?

slow movement, a symptom of Parkinson’s disease