Peripheral Somatosensory System
generally explain the three neuron pathway of the somatosensory system?
1st order neuron: brings info from sensory receptors into the spinal cord
2nd order neuron: conveys information between the spinal cord or brainstem to the thalamus
3rd order neuron: conveys info from the thalamus to the cerebral cortex
This phenomenon, often associated with chronic pain conditions, describes an amplification of neural signaling within the central nervous system, leading to increased sensitivity to pain stimuli.
What is central desensitization?
The cell bodies of spinal LMNs are located in the __________ of the spinal cord.
ventral horn
This type of pain persists beyond the expected time of healing and is often associated with chronic conditions, while this other type of pain arises as a result of tissue damage or injury and typically resolves once the underlying cause is treated.
What is chronic pain? What is acute pain?
This syndrome results from a hemisection of the cord. Below the level of the lesion, voluntary motor control, conscious proprioception, and light touch are lost ipsilaterally; nociceptive and temperature sensation is lost contralaterally.
What is Brown-Sequard Syndrome?
what test is used to distinguish between cerebellar ataxia and sensory ataxia?
Romberg Test
Presented as recurrent episodes. Must last 4 to 72 hours. Have at least of the two following characteristics: unilateral location, pulsating quality, moderate or severe pain intensity, and be aggravated by or cause avoidance of routine physical activity such as walking. In addition, must be accompanied by at least one of the following: nausea, vomiting, photophobia, or phonophobia (sensitivity to light and sound, respectively)
What is a migraine?
A group of muscles innervated by a single spinal nerve is referred to as?
a myotome
Phantom pain is categorized as what type of pain?
chronic secondary (neuropathic pain)
What level and above requires a ventilator for a complete spinal cord lesion?
What is C4
this term is known as the dysfunction or pathology of one or more peripheral nerves
what is neuropathy?
if you stub your toe, the information will travel on the ______ pathway to let you know thelocation (toe), size (front corner of your toes), and intensity (hit your toehard) of the cause of the pain
high accuracy
This type of reflex is a muscle contraction in response to a quick stretch
Phasic stretch reflex
is the increased pain in response to a nociceptive stimulus and is due to sensitized responses of neurons in the nociceptive system
hyperalgesia
Lesions above T6 level prevent most of the spinal cord from receiving signals from the brain that inhibit sympathetic activity, as a result there will be an increase in blood pressure from the vasoconstriction. Other symptoms include sweating above the lesion and a pounding headache. This is known as...
What is autonomic dysreflexia?
this joint receptor is located in the joint capsule and is a tonic receptor that signals the extremes of joint range and respond more to passive than to active movement
what is Ruffini's endings?
this column carries information about pain, temperature and crude touch
what is the anterolateral system?
This spinal tract facilitates lower motor neurons to control bilateral postural, antigravity, and gross limb movement muscles of the entire body
what is the reticulospinal tract?
characterized as tenderness of muscles and adjacent soft tissues, stiffness of muscles, and aching pain, widespread pain that does not follow dermatomal or peripheral nerve distributions resulting from abnormal pain processing due to central sensitization
what is fibromyalgia?
UMN lesions occur in the motor pathways of the central nervous system (CNS), including the brain and spinal cord. UMN lesions typically result in Muscle hypertonia, paresis, spasticity, clonus, Babinski’s sign.
LMN lesions occur at or below the level of the anterior horn cell in the spinal cord or in the peripheral nerves. Symptoms typically include flaccidity, decreased or absent reflexes, and atrophy.
these type of fibers produce much less force and are smaller than the counterpart fibers. the purpose is not to produce force, but to provide sensation.
what are intrafusal fibers.
these are our two conscious relay pathways
the dorsal column medial lemniscal pathway and the spinothalamic tract of the anterolateral system
Responsible for conveying signals from the brain to the spinal cord, these neurons play a key role in initiating and modulating voluntary movements.
What are upper motor neurons?
this pain system processes the motivational-affective and cognitive-evaluative aspects of pain; it uses a divergent pathway
what is the slow medial nociceptive pathway?
Which of the following best describes the role of stepping pattern generators (SPGs) in locomotion?
A) SPGs are specialized neurons located in the spinal cord responsible for generating rhythmic motor patterns involved in walking and running.
B) SPGs are sensory receptors in the lower limbs that provide feedback to the brain about the position and movement of the legs during locomotion.
C) SPGs are clusters of neurons in the brainstem that regulate the timing and coordination of muscle contractions during voluntary movements.
D) SPGs are structures in the cerebellum that integrate sensory information and coordinate muscle activity to maintain balance and stability during walking.
A) SPGs are specialized neurons located in the spinal cord responsible for generating rhythmic motor patterns involved in walking and running.