General somatic afferent system

Question 1

Describe the conscious perception pathway

Answer 1

1. Sensory receptors
   Different types of receptors are specialised to respond to specific stimuli
2. Peripheral nerve fibres
   Sensory information from receptors is transmitted to CNS through peripheral nerve fibres
   A-delta & C fibres are involved in transmitting pain & temperature
   A-beta fibres are responsible for touch
3. Dorsal root ganglia
   Cell bodies of peripheral sensory neurons are located in dorsal root ganglia alongside the spinal cord
   DRG neurons receive & integrate sensory signals before transmitting them to CNS
4. Spinal cord
   Sensory information enters spinal cord through dorsal roots
   Sensory signals are relayed to various regions
5. Ascending pathways
   Ascending pathways carry sensory information from spinal cord to high brain centres
   Including thalamus & cerebral cortex
   There are multiple ascending pathways:
   Spinothalamic tract is responsible for transmitting pain & temperature information
6. Thalamus
   Acts as relay station, receiving sensory information from ascending pathways & transmitting it to cerebral cortex
7. Cerebral cortex
   Sensory information reaches cerebral cortex where it is processed