Sensory Function Flashcards
What is the function of sensory physiology?
Allows us to interact with the world around us and transduce/convert different types of energy into action potentials
Where is sensory information transmitted to?
The sensory cortex - central sulcus
What are nociceptors?
Noxious stimuli (generate pain)
What are proprioceptors?
Give information about body and limb position
What is the difference between rapidly adapting and slowly adapting sensory receptors?
Slowly adapting receptors continue to discharge as long as the receptor is stimulated
Rapidly adapting receptors don’t - discharge is reduced or may cease
Where do sensory neurones enter the spinal cord?
Dorsal horn of vertebrae
What is a receptive field?
The area of skin that once stimulated produces a response in a sensory neuron
What is the relationship between receptive fields and numbers of receptors?
Vary inversely
What does the two-point discrimination test measure?
Measure of tactile acuity
What are generator/receptor potentials?
Local graded changes in membrane potential
What nerve transports sensory information from the face?
Trigeminal nerve
Where do sensory neurons synapse?
Brainstem nuclei
What does the medial lemniscal tract sense?
Proprioception
Discriminative touch
Pressure and vibration sense
Sterognosis
What does the spinothalamic tract sense?
Pain
Temperature
Crude touch
Itch and tickle
Describe the organisation of the medial lemniscal tract.
Dorsal columns are first order neurons composed of large myelinated axons which enter the dorsal route
Travel up the cord in a highly organised pathway - somatotopic representation
Synapse in medulla on either of the dorsal column nuclei
Second order neurons (medial lemniscus) synapse in thalamus
