10-sensory And Motor Systems Flashcards
Sensation vs perception
Sensation = detection of changes in external or internal environment Perception = conscious awareness and perception of sensations
Sensory – is one unique type of sensation (pain, touch, vision, hearing)
Modality
In the process of sensation, – of stimulus involves converting energy from stimulus into graded potential
Transduction of stimulus
*think conduction
– order neurons carry sensory impulses from PNS to CNS
First order neurons
Last step of sensation
Integration of sensory input by cerebral cortex
3 types of sensory receptors by location
- Exteroreceptors - at or near external surface of body
- Interoreceptors - in blood vessels, visceral organs, muscles and nervous system
- Proprioceptors - muscles, tendons, joints, inner ear for body position and movement
6 types of sensory receptors classified by stimulus
- mechanoreceptors : deformation, stretching, bending of cells
- thermo receptors
- nocireceptors : pain
- photoreceptors
- chemoreceptors
- osmoreceptors: osmotic pressure of bodily fluids
Rapidly adapting receptors for
Pressure, touch, smell
Slowly adapting receptors for
Pain, proprioception (body position), blood chemical levels
4 modalities of somatic sensations
Tactile
Thermal
Pain
Proprioceptive sensations
Subdivisions of Tactile sensations
Touch, pressure, vibration, itch, tickle
Thermal sensations are conducted thru
Free nerve endings
Types of pain sensations
Superficial and deep somatic pain
Visceral pain - internal organs
What is referred pain
Visceral (organs) pain perceived in skin overlying affected organ
Proprioception end
Bin rotation web
Name the 3 components of proprioceptive sensations
- Muscle spindles located in skeletal mm measure muscle length/stretch and more precise movement = more muscle spindles
- Tendon organs - measure muscle tension
- Joint kinesthetic receptors - artiularbcapsules capsules or synovial joints sense joint position and movement
What relays info from somatic sensory receptors to the primary somatosensory area in the cerebral cortex and cerebellum
Somatic sensory pathways
Ascending somatic sensory pathway is set of 3 neurons
First order - impulse from somatic receptor to CNS
Second order neuron-cross over in spinal cord (spinothalamic tract) or brain stem, then carry impulse to thalamus (on opposite side)
Third order - impulse from thalamus to postcentral gyrus on same side
Relay stations where ascending neuron synapse
Thalamus, brain stem, spinal cord
The primary – area is in cerebral cortex of parietal lobe
- each region receives sensory input from different part of body
- receive input from opposite side
Somatosensory area
Primary – area is in cerebral cortex of precentral gyri of frontal lobe
Primary motor area
The – – – pathways are descending somatic motor pathways from brain to synapse with lower motor neurons
Upper motor neuron pathways
Describe the 3 pathways to relay info from brain to effectors
Lateral corticospinal pathway: hands and feet; decussate at medulla oblongata
Anterior corticospinal pathway: trunk and proximal limb; decussate at spinal cord levels
Corticobulbar : head! bulb = head
– – is increase in axon terminals in presynaptic neurons and increase in dendrites of post synaptic neurons
Intensive learning
