Flashcards in Spinal Cord-- Ascending Systems Deck (15)
Function(s) of the Dorsal Column Pathway (DCP)
(1) 2 point discrimination
(2) Vibration sense
What is Proprioception?
The ability to consciously sense positioning of a limb even with no visual stimulation. It is due to the perception of muscle spindle and Golgi tendon receptors.
What type of fibers make up the dorsal column pathway?
Important receptor types affiliated with the DCP
(1) Meissner's Corpuscle
(2) Pacinian Corpuscle
(3) Ruffini Ending
(4) Joint Receptor
(5) Neuromuscular Spindle
(6) Golgi Tendon Organs
Information below T6 is found
Medially in what is called the fasciulus gracillis
Information above T6, including the head, is found
Laterally in the fasciculus cuneatus
Where second order fibers pile up after exiting the gracile and cuneate nuclei
How does the nervous signal end up at the opposite end from which it began?
Crosses the medulla at the internal arcuate fibers
Area 312 (broddman's area)
Somatosensory cortex. It handles afferent information
What area is in front of the central sulcus?
Area 4, which controls motor functions. It has efferent information.
What part of the body has its sensory towards the midline of the parietal cortex? Towards the lateral end?
From midline to lateral end:
Feet, hands, some head (minimal as CNV mainly handles this), large area for lips.
General path for dorsal column pathway
(1) Enters dorsal root
(2) 1st synapse- nucleus cuneatus/gracilis
(3) 2nd synapse- VPL (after traveling via medial lamiscus)
(4) 312 area
Dorsal spinocerebellar and ventral spinocerebellar tracts register...
Loss of Tabes dorsalis
Issues with dorsal column pathway
Positive if person requires vision in order to stand steadily. Said to be positive for patients with dorsal column injury. Negative for cerebellar ataxia.