Somatic Senses

General Sensory System

Sensation

Define Stimulus Type Sensory Organ Sensory Receptors

Exteroceptors Interoceptors Proprioceptors

Receptor Potential Transduction Pathway Response Adaptation

Somatosensory Receptors

Nocireceptors Thermoreceptors Mechanoreceptors

Tactile Baroreceptors Proprioceptors

Chemoreceptors

Somatosensory Exteroceptors

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

Pseudounipolar Neuron

Ascending Sensory Tracts

Crossing Over

General Somatosensory Pathway

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

Sensory Cortex

Sensory Homunculus

Association Areas

Touch and Pressure

Meissners Corpuscles

Pacinian Corpuscles

Merkel Disks

Posterior [Dorsal] Columns

Sensory Receptors: Pain

Sensory Receptors: Temperature

Proprioception

Histology of Proprioceptors

Muscle Spindle Fibers

Golgi Tendon Organ

Experiments

Discrimination testsLocation DensityThresholdAdaptation

Testing Fields for Pressure

Depth and Threshold

Receptor Potentials

Receptor Testing Variations

Temperature

Somatosensory Responds to:

Contact with foreign objectsWarningFeedbackDevelopment

Changes in temperatureWarningHeat regulation

Avoid Damage

Dermatomes

Skin region monitored

Sensory receptors Spinal Nerve pair

maps the body CN V supplies face

Cranial Nerves with Somatosensory

CN V Ophthalmic Br. Maxillary Br. Mandibular Br.

CN X ANS

parasympathetic for pain

Reflex Response

Pain and Temperature Reflex

Reflex Testing

Motor Response from Higher Centers

Descending Motor Tracts

Corticospinal Lateral Anterior Corticobulbar

Vestibulospinal Tectospinal Recticulospinal Rubrospinal