TRACTS

Question 1

Corticobulbospinal FUNCTION

Answer 1

Descending
Modulates sensory input and spinal reflexes
Arises from parietal lobe

Question 2

Corticospinal PATHWAY

Answer 2

Motor cortex -> through IC -> down into midbrain cerebral peduncles -> medullary pyramids -> top of spinal cord to decussate -> form lateral and anterior corticospinal tracts

Question 3

Lateral Vestibulospinal FUNCTION

Answer 3

Posture and balance

Question 4

Lateral Vestibulospinal PATHWAY

Answer 4

Vestibular apparatus inputs –> Vestibular nuclei -> ipsilateral projection to antigravity muscles

Question 5

Reticulospinal FUNCTION

Answer 5

General arousal of spinal cord, autonomic control, drive to respiration

Question 6

Reticulospinal PATHWAY

Answer 6

Reticular formation -> bilaterally down cord

Connects neurones from respiratory and vasomotor centres in medulla with preganglionic neurons where they synapse for autonomic control

Question 7

Rubrospinal FUNCTION

Answer 7

Cerebellar commands carried to cord

Question 8

Rubrospinal PATHWAY

Answer 8

Input from cerebellum -> red nucleus in midbrain -> cord

Question 9

Tectospinal FUNCTION

Answer 9

Co-ordinates head and eye voluntary movements

Activating reflex movements of the head in response to visual and auditory stimuli

Question 10

Tectospinal PATHWAY

Answer 10

Superior colliculus/Optic tectum -> contralateral cervical spinal cord -> laminae 6-8

Question 11

Medial Vestibulospinal tract FUNCTION

Answer 11

DCML continuation
Mediates reflex co-ordination of the head and neck muscles with the extraocular eye muscles maintaining objects in view despite body movements

Question 12

Dorsal Spinocerebellar PATHWAY

Answer 12

Afferents from muscle spindles and Golgi tendon organ -> brainstem -> cerebellum inferior peduncle input
Ipsilateral

Question 13

Dorsal Spinocerebellar FUNCTION

Answer 13

Carries information from proprioceptors (joints, Golgi tendon organs and muscle spindles)

Question 14

Ventral Spinocerebellar PATHWAY

Answer 14

Crosses in spinal cord then crosses again in brainstem

- to cerebellum

Question 15

Ventral Spinocerebellar FUNCTION

Answer 15

Carries information about the state of reflexes in the cord

Question 16

Anterior/neo Spinothalamic tract

Answer 16

• decussation to anterior SPT
• innervate VPL and VPM nuclei of thalamus
• also VPI nucleus of thalamus
• also lateral nuclei of thalamus
• also somatosensory thalamus

Question 17

Anterior/Neo SPT -> central lateral nuclei of thalamus -> ?

Answer 17

• Anterior cingulate cortex (emotion/motivation)

- PF cortex and striatum -> cognitive function and strategy

Question 18

Anterior neo SPT -> VPL/VPM nuclei of thalamus -> ?

Answer 18

• somatosensory cortex -> localisation and physical intensity of stimulus

Question 19

Anterior SPT -> somatosensory thalamus ->

Answer 19

Secondary somatosensory cortex

Question 20

Anterior/neo SPT?

Answer 20

Discriminative aspects of pain

• reflex withdrawal
• first to be involved

Question 21

Lateral/Paleo SPT?

Answer 21

• mainly C fibres but some A-delta innervate projection neurons in lamina 1
• decussate posterior/medial parts of thalamus
• to mediodorsal nucleus and posterior thalamus

Question 22

Lateral/paleo SPT -> mediodorsal nucleus ->

Answer 22

ACC

Question 23

Lateral/SPT -> posterior thalamus ->

Answer 23

Anterior/rostral insula

emotion, quality, autonomic integration

Question 24

Lateral/paleo SPT Function

Answer 24

Second involved
Punishing aspects of pain
- say ouch it hurts

Question 25

What else does the lateral/paleo SPT project to produce unpleasant plain?

Answer 25

• limbic system

subjective sensations of pain and pleasure

Question 26

LST collateral projection significance?

Answer 26

Stimulated general arousal and focussing attention of painful region
- LST travels upwards projecting to reticular formation, PAG and amygdala

Question 27

What is the role of the different projections in collateral projections?

Answer 27

RF (arousing and alerting cortex)
PAG (descending pain modulation)
Amygdala (Limbic activation, visceral autonomic integration)