Sensory receptors Flashcards
What are ‘slowly adapting’ receptors?
- ‘Tonic’ receptors
- Respond to prolonged stimulation
- Maintain firing but decrease rate throughout duration
What are ‘rapidly adapting’ receptors?
- ‘Phasic’ receptors
- Respond at the beginning and end of stimulus
What is divergence?
One primary neuron activating more than one secondary neuron
What is convergence?
Many primary neurons onto one secondary order neuron
Why are inhibitory neurons important?
- Ensure the signal in the most active neuron is propagated
- Strong, sharp, time-specific signal
What is stimulus intensity determined by?
Response amplitude of receptor (receptor potential) and the firing rate of action potential
What is a receptive field?
- A region of skin innvovated by the terminals of one receptor neuron
- Different areas of the body have different sizes of receptive field
- Larger stimulus, more RF activated, more receptor potentials
What is the labelled line code?
- Codes for modality of a stimulus
- Nerves which use the SAME physiological principles
- Able to generate DIFFERENT sensations, depending on were in the CNS the neurons connect to and where their receptors are found
- Each receptor type is connected to a specific line of communication
- Makes connections with specific parts of the CNS
3 steps of stimulus processing?
1) Physical stimulus received
2) Transduction into electrical signal in the PNS
3) Evoke perception or conscious experience in the the CNS
What receptors involved in prorprioception?
Muscle spindles
What receptors involved in taste and smell?
Chemoreceptors
What receptors involved in pain and temperature?
Free nerve endings
What receptors involved in hearing and balance?
Mechanoreceptors
