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Physiology 1Physiology 1

Sensory SystemsSensory Systems

Sensory information; how the brain Sensory information; how the brain gets info about the environmentgets info about the environment

Five SensesFive Senses–– Touch Touch –– SightSight–– HearingHearing–– TasteTaste–– SmellSmell

Sensory SystemsSensory Systems

Sensation = sensory information reaching Sensation = sensory information reaching the brain.the brain.Perception = sensory information reaching Perception = sensory information reaching consciousnessconsciousness

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Sensory receptorsSensory receptors

Respond to changes in the internal or Respond to changes in the internal or external environment with changes in external environment with changes in neural activity.neural activity.Are not the same as chemical receptorsAre not the same as chemical receptors

Skin layersSkin layers

Stratum Stratum CorneumCorneum = = dead epitheliumdead epitheliumStratum Stratum LucidumLucidum = = wax layerwax layerStratum Stratum granulosumgranulosum= pigments= pigmentsStratum Stratum SpinosumSpinosum = = desmasomesdesmasomes bound bound togethertogetherStratum Stratum BasaleBasale = = dividing basal dividing basal epitheli mepithelium

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Sensory receptors in skinSensory receptors in skin

Free nerve endingsMerkel’s diskMeissner’s corpusclePacinian corpuscleHair follicle receptors

The physical nature of sensory The physical nature of sensory receptors.receptors.

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Information contained in sensory Information contained in sensory receptor outputsreceptor outputs

DurationDurationIntensityIntensity

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Sensory MappingSensory Mapping

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The visual systemThe visual system

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Organization of the retinaOrganization of the retina

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Color VisionColor Vision

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The Brain actively pursues making The Brain actively pursues making sense out of its environmentsense out of its environment

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Some tasks are inherently easier Some tasks are inherently easier for the brain to do than others.for the brain to do than others.

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HearingHearing

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Vestibular systemVestibular system

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TasteTaste

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