Sensory Physiology. Sensation State of external/internal awareness Stimulus Receptor Nerve impulse to brain.

Sensory PhysiologySensory Physiology

SensationSensation

State of external/internal awarenessStimulusReceptorNerve impulse to brain

Characteristics of SensationsCharacteristics of Sensations

Projection– Phantom Pain

AdaptationAfterimagesModality

ReceptorsReceptors

DendritesGenerator potential

Receptors according to Receptors according to stimulus locationstimulus location

ExteroceptorsEnteroceptors = VisceroceptorsProprioceptors

Receptors according to Type Receptors according to Type of Stimulusof Stimulus

MechanoreceptorsThermoreceptorsChemoreceptorsPhotoreceptorsNociceptors (pain)

Cutaneous SensationsCutaneous Sensations

Receptor Fields– Two point discrimination/threshold– Lateral inhibition

Cutaneous SensationsCutaneous Sensations

Tactile sensations– Meissner’s corpuscles = Touch corpuscles– Hair root plexus– Free nerve endings

Cutaneous SensationsCutaneous Sensations

Pressure sensations– Pacinian corpuscles

Thermal sensations– Free nerve endings

Pain sensation– Free nerve endings– Referred pain

Proprioceptive Sensations = Proprioceptive Sensations = Kinesthetic SenseKinesthetic Sense

Muscle spindles = Intrafusal fiber– Stretch receptors

Tendon organs = Golgi tendon organs– Contraction receptors

Misc. joint receptors

SPECIAL SENSESSPECIAL SENSES

OlfactionOlfaction

Receptors in upper nasal mucosaOlfactory nerveOlfactory bulbOlfactory tractTemporal lobe of cerebral cortex

GustationGustation

Taste buds are receptorsTaste poreLiquidTaste zones

GustationGustation

Sensory nerve fibers– Facial– Glossopharyngeal– Vagus

Brain stemThalamusParietal lobe of cerebral cortex