Neuroanatomy Module: Somatosensory Pathways

What is the primary characteristic that distinguishes general functional components from special functional components of peripheral nerves?

Their specific functions devoted to a particular organ or group of muscles

Which of the following structures is embryologically derived from the body wall or somatic mesoderm?

Dermis of the skin

What is the term for nerve cell fibers that transmit impulses towards the CNS from the periphery?

Afferent

What is the term for a collection of nerve cell bodies in the PNS?

Ganglion Signup and view all the answers

Which of the following is an example of a visceral structure?

GI tract Signup and view all the answers

What is the primary difference between somatic and visceral nerves?

Their embryological origin of tissue or body part being innervated Signup and view all the answers

What is the term for a bundle of nerve fibers with common origin and termination in the CNS?

Nerve Tract Signup and view all the answers

What is the term for nerve cell fibers that transmit impulses away from the CNS towards the periphery?

Efferent Signup and view all the answers

Which of the following is NOT a component of the pathways for general somatic sensation?

Basal ganglia Signup and view all the answers

Which tract system is responsible for transmitting sensation from the body to the thalamus?

Anterolateral (Spinothalamic) Tract System Signup and view all the answers

What is the role of the dorsal root ganglion in the pathway for general somatic sensation?

It transmits sensory information from the periphery to the central nervous system Signup and view all the answers

Which pathway is involved in the direct and consensual corneal blink reflexes?

Trigeminothalamic tract Signup and view all the answers

What is the function of the ventral posterolateral nucleus of the thalamus?

It relays sensory information from the thalamus to the primary sensory cortex Signup and view all the answers

Which pathway is involved in unconscious proprioception?

Spinocerebellar tract Signup and view all the answers

Which type of receptor is responsible for detecting specific chemicals in the blood?

Chemoreceptor Signup and view all the answers

What type of stimulus do mechanoreceptors respond to?

Excess pressure or deformation Signup and view all the answers

Which type of receptor is responsible for mediating slow pain?

Nociceptor Signup and view all the answers

What is the effect of stimulating the motor nucleus of CN VII in the direct corneal blink reflex pathway?

Ipsilateral eye will close Signup and view all the answers

What type of receptor is responsible for detecting itch sensations?

Prurireceptor Signup and view all the answers

What is the function of the carotid body in the context of blood gas detection?

Responds to decreased blood pH or acidosis Signup and view all the answers

What is the type of receptor that responds to extreme temperatures?

Thermoreceptor Signup and view all the answers

What is the afferent arm of the direct corneal blink reflex pathway?

CN V1 (Ophthalmic) Signup and view all the answers

What is the afferent arm of the indirect corneal reflex pathway?

Same as the direct corneal blink reflex Signup and view all the answers

What is the function of the medial longitudinal fasciculus in the indirect corneal reflex pathway?

Transmitting signals from the spinal nucleus to the contralateral facial motor nucleus Signup and view all the answers

What is the result of stimulating the right cornea in the indirect corneal reflex?

Both the right and left eyes blink simultaneously Signup and view all the answers

What is the purpose of checking for the direct and consensual corneal blink reflexes in a neurological examination?

To assess the function of both the trigeminal and facial nerves Signup and view all the answers

What is the result of a lesion at a particular part of the reflex arc?

Failure to elicit one or both reflexes on either eye Signup and view all the answers

What is the role of the spinal nucleus of CN V in the indirect corneal reflex pathway?

It gives rise to axons that cross the midline to the contralateral facial motor nucleus Signup and view all the answers

What is the function of the contralateral facial motor nucleus in the indirect corneal reflex pathway?

It innervates the contralateral orbicularis oculi Signup and view all the answers

What can be identified by checking for the direct and consensual corneal blink reflexes on both eyes?

The most likely location of a lesion in a patient Signup and view all the answers

What kind of sensory receptor is typically found in the skin?

Free Nerve Ending Signup and view all the answers

Where is the location of the VPM of the Thalamus?

Just above the lip of the Sylvian fissure (left side) Signup and view all the answers

What type of sensation is affected in V.J.'s right face, arm, and leg?

Pain, temperature, and light touch Signup and view all the answers

Which tract is responsible for transmitting pain and temperature information from the face?

Ventral Trigeminothalamic Tract Signup and view all the answers

What is the function of the Spinal Nucleus of CN V?

To transmit pain and temperature information from the face Signup and view all the answers

What is the significance of V.J.'s 2-point discrimination test result of 15 mm on the tip of her right index finger?

It indicates decreased sensation in her right hand Signup and view all the answers

Which pathway is responsible for transmitting vibration sense from the right hand?

Dorsal Column Medial Lemniscus Signup and view all the answers

Where is the Gasserian Ganglion located?

In the trigeminal nerve Signup and view all the answers

What is the function of the Lateral Spinothalamic Tract?

To transmit pain and temperature information from the body Signup and view all the answers

What is the significance of V.J.'s intact direct and consensual corneal reflex?

It indicates normal function of her trigeminal nerve Signup and view all the answers