Sensory & Motor Systems Flashcards
Why do the sensory and motor systems work?
Physics and nervous conduction (energy transfer and transformation)
What are the three steps of how the sensory and motor systems work?
Sensory input – integration – motor output
What are the 4 basic functions of sensory pathways? RTTI
Reception, transduction, transmission, and integration
Reception
Specialized receptors receiving external stimuli as some form of energy.
Something has to change in you when you sense a change in the environment.
Transduction
Stimulus is converted into electrical signal (via a change in membrane potential)
Transmission
Passage of electrical energy via neurons.
Taking the activated neuron and sending the signal to the brain.
Integration
CNS and ganglia receive electrical signals from neurons and perception occurs.
Perception (happens b/c of integration)
The brains construction of stimuli
Sensory input undergoes _________ and _______ as it is transduced.
Amplification and adaptation
Amplification
Strengthening of stimulus energy by cells in sensory pathways. Response can quickly be amplified.
Adaptation
Decrease in responsiveness to continued stimulation. Ex. ‘Forgetting’ your glasses are on your head
What are the 5 categories of sensory receptors based on?
The energy they transduce (sense)!
What are the 5 categories of sensory receptors and what do they detect?
Mechanoreceptors (touch)
Chemoreceptors (chemicals)
Electromagnetic receptors (light)
Thermo-receptors (temperature)
Nociceptors/pain receptors (extremes; a cut)
What 3 types of receptors are in the skin?
Mechanoreceptors, thermo-receptors, and pain receptors (nociceptors)
What kind of receptor is in the ears? Eyes?
Ears - mechanoreceptors mediate ‘hearing’
Eyes - electromagnetic receptors mediate vision
What kind of receptor is in the tongue? Nose?
Tongue - chemoreceptors associated with taste
Nose - chemoreceptors associated with smell
What is used by mechanoreceptors in order to generate an action potential?
Mechanically-gated ion channels!
Describe the pathway which sensory receptors in the skin sense a change. (Mechanoreceptors)
The membrane of the cells in the skin are squished when the skin is touched, which opens mechanically-mediated ion channels, this allows the ion to flow through, the start of an action potential!
Note - receptors deeper in the skin respond to more pressured touch, versus surface-level receptors
When you get to this slide, open the diagram of the ear and go over it!
Outer ear: auditory canal
Middle ear: Tympanic membrane, malleus, incus, stapes
Inner ear: Semicircular canals, auditory nerve, cochlea
Describe the pathway through the ear which sensory receptors sense a change. (Mechanoreceptors)
When air comes down the auditory canal, it shakes the eardrum, the eardrum shaking makes the middle ear shake (malleus, incus, and stapes), that shaking is then sent to the cochlea (inner ear).
Describe what happens once the vibration signal reaches the cochlea (inner ear). Whats inside the cochlea?
Inside the cochlea there are hair cells that start to move with the shaking vibration. When they bend in one direction, that stimulates the release of neurotransmitters, and when they bend in the opposite direction, they release less neurotransmitters.
This overall leads to a complex series of action potentials (different for different sound wavelengths) that fire in the next neuron.
How do fish ‘hear’?
They have a sense organ called the lateral line, that senses the water waves. They have hair cells like we do, that can ‘read’ the different vibrations in the water.
