Sensation Flashcards
What the two broad classes of sensations?
- General - tactile, thermal, pain and proprioceptive
2. Special - smell, taste, vision, hearing and equilibrium/balance
What are the 4 events that occur to process sensation?
STGI
- stimulation of sensory receptors
- transduction (conversion) of the stimulus
- generation of nerve impulse
- integration of sensory input
Classification of sensory receptors: microscopic structure
- Free nerve endings
- Encapsulated nerve endings
- Separate cells
FES
Classification of sensory nerve endings: receptor location and activating stimuli
- Exteroceptors - external stimuli, e.g. hearing, touch
- Interoceptors - monitor internal env. e.g. muscles, blood vessels
- Proprioceptors - info about body position/location) e.g. muscles, inner ear
Classification of sensory receptors: type of stimulus deteced
- Mechanoreceptor - mechanical stimuli (touch)
- Thermoreceptor - temperature
- Nociceptor - potentially dangerous events
- Photoreceptor - light
- Chemoreceptor - chemicals in mouth, nose (taste)
- Osmoreceptor - osmotic pressure
MTNPCO
What are somatic sensations? Give one example
arise from stimulation of sensory receptors located in skin
mouth, vagina, anus, muscles, tendons, joints, inner ear
What are the 4 modalities of somatic sensation?
Tactile
Thermal
Pain
Proprioceptive
TTPP
What is the 1st order somatic sensory pathway?
conducts impulses from somatic receptors to the brain stem or spinal cord
What is the 2nd order neuron somatic sensory pathway?
conduct impulses from brain stem or spinal cord to thalamus (cross over to opposite side of body)
What is the 3rd order neuron of the somatic sensory pathway?
conduct impulses from thalamus to cerebral cortex
List one sensation that the posterior column-medial lemniscus pathway registers.
Touch
Pressure
List one sensation that the anterolateral pathway registers.
Tickle
Temperature
Pain
