Spinal tracts Flashcards
(64 cards)
What is the purpose of different segments in the spinal cord?
They have different workloads.
What is the reason for cervical and lumbar enlargement in the spinal cord?
They have extra inputs and outputs and required to manage sensory and motor.
What protection does the spinal cord have?
Meninges.
What is the purpose of thin connective tissue in the spinal cord?
Anchors the spinal cord to the area of the coccyx.
What is the general overview of the CNS?
Ascending sensory pathways into the brain, descending motor pathways to the body (away from the brain).
What are sensory pathways?
Carry info from sensory receptors to the brain.
Which info reaches the cerebral cortex?
The conscious.
Which info doesnt reach cerebral cortex?
The unconscious (eg moving leg)- carry to the cerebellum.
What are the unencapsulated nerve endings?
Free nerve endings, tactile discs, hair receptors.
What are free nerve endings?
Pain, heat and cold. Found in epithelia and connective tissues.
What are tactile discs?
Light, touch, texture, edges and shapes. Found in stratum basale.
What are hair receptors?
Movement of hairs, found around the hair follicle.
What are the encapsulated nerve endings?
Tactile corpuscles, Krause end bulbs, lamellated corpuscles, Ruffini corpuscles, muscle spindles, Golgi tendon organs.
What are tactile corpuscles?
Light, touch and texture. In palms, eyelids, nipples, genitals.
What are Krause end bulbs?
Similar to tactile corpuscles, in mucous membranes.
What are lamellated corpuscles?
Deep pressure, stretch, tickle, vibration. Found in joint capsules, breasts, genitals.
What are Ruffini corpuscles?
Heavy touch, pressure, stretching of skin, joint movements. In dermis and joint capsules.
What are muscle spindles?
Muscle stretch. Found in skeletal muscles near tendon.
What are Golgi tendon organs?
Tension on tendons and found in tendons.
Which sensory receptors help understand the position of movement of muscles and joints?
Ruffini corpuscles, muscle spindles and Golgi tendon organs.
What is the meaning of decussation?
Crossing of nerve fibres (cross the midline of the body).
What is the process of the generic sensory pathway?
-The 1st order neuron (sensory cell body in the dorsal route ganglion) -2nd order neuron (cell body in the dorsal grey matter).
-3rd order neuron (cell body in the thalamus)- decussates and is like a distribution centre- the sensory info is sent here and directed where to go).
How do these pathways travel?
Through action potentials (APs).
Where is the 1st order neuron in the spinothalemic pathway?
Cell body in the dorsal route ganglia.