Somatic Senses

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Somatic Senses

• General Sensory System

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Sensation

• Define
• Stimulus Type
• Sensory Organ
• Sensory Receptors
• Exteroceptors
• Interoceptors
• Proprioceptors
• Receptor Potential
• Transduction
• Pathway
• Response
• Adaptation

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Somatosensory Receptors

• Nocireceptors
• Thermoreceptors
• Mechanoreceptors
• Tactile
• Baroreceptors
• Proprioceptors
• Chemoreceptors

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Somatosensory Exteroceptors
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Somatic Sensory Modalities

• Discriminative Touch
• Pressure, Vibration, Texture
• Rapidly Adapting
• Meissners Corpuscles
• Pacinian Corpuscles
• Slowly Adapting
• Merkel Disks
• Pain and Temperature
• Free nerve endings
• Fast Pain A Fibers
• Slow Pain C Fibers
• Ruffini corpuscle heat
• Krause corpuscle cold
• Proprioception
• Muscle Spindle
• Golgi Tendon Organ

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Pseudounipolar Neuron
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Ascending Sensory Tracts
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Crossing Over
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General Somatosensory Pathway
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Ascending Sensory Spinal Cord Tract Information

• Touch and Pressure
• Discriminative
• Dorsal Columns Fasciculus Group
• Crude
• Anterior Spinal Thalamic
• Pain and Temperature
• Lateral Spinal Thalamic
• Proprioception
• Length Posterior Spinocerebellar
• Force Anterior Spinocerebellar

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Sensory Cortex
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Sensory Homunculus
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Association Areas
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Touch and Pressure
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Meissners Corpuscles
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Pacinian Corpuscles
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Merkel Disks
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Posterior Dorsal Columns
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Sensory Receptors Pain
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Sensory Receptors Temperature
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Proprioception
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Histology of Proprioceptors
Golgi Tendon Organ
Muscle Spindle Fibers
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Experiments

• Discrimination tests
• Location
• Density
• Threshold
• Adaptation

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Testing Fields for Pressure
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Depth and Threshold
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Receptor Potentials
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Receptor Testing Variations
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Temperature
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Somatosensory Responds to

• Contact with foreign objects
• Warning
• Feedback
• Development
• Changes in temperature
• Warning
• Heat regulation
• Avoid Damage

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Dermatomes

• Skin region monitored
• Sensory receptors
• Spinal Nerve pair maps the body
• CN V supplies face

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Cranial Nerves with Somatosensory

• CN V
• Ophthalmic Br.
• Maxillary Br.
• Mandibular Br.
• CN X
• ANS parasympathetic for pain

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Reflex Response
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Pain and Temperature Reflex
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Reflex Testing
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Motor Response from Higher Centers
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Descending Motor Tracts

• Corticospinal
• Lateral
• Anterior
• Corticobulbar
• Vestibulospinal
• Tectospinal
• Recticulospinal
• Rubrospinal