Somatic Sensation Flashcards
What is a somatic sense?
Mechanoreceptors (touch, pressure, vibration)
Nociceptors (pain)
Thermoreceptors (temperature)
Chemoreceptors (chemicals)
What is a ‘special’ sense?
Vision, hearing, balance, taste, smell
Each have a localised organ or structure associated with their reception
What is a mechanoreceptor?
Stimulated by physical forces that distort the plasma membrane
Nerve endings contain mechanically gated ion channels
What are nociceptors?
Noxious stimuli trigger perception of pain
Widespread receptors
Usually free nerve endings
What is signal transduction?
Sensory receptors have a specialisation that makes them sensitive to a particular stimulus. The process of converting a stimulus of one form is a signal transduction
What is a receptive field?
Endings of any single receptor spread over a restricted area. Neuron only stimulated when stimulus is presented within the area its receptors are located in
What is phasic receptor?
Normally silent, respond briefly to change
Fast adapting
What is a tonic receptor?
Continually active to reflect background level of stimulation
AP frequency changes when stimulus intensity changes
Slow adapting
What are the four types of information coding?
Modality (type)
Intensity (strength)
Duration (period)
Location (place)
If you increase stimulus what happens to AP frequency?
Increased stimulus increases AP frequency
Stronger stimuli can also activate more receptors and AP in more sensory axons
