Copyright © 2007 Pearson Education, Inc Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The General Senses General versus Special Senses General senses— Temperature Pain Touch Pressure Vibration Proprioception本體感覺. Receptors throughout the body Special senses—Smell, taste, vision, balance, and hearing. Receptors located in sense organs感覺器官 (e.g., ear, eye). Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Receptors and Receptive Fields The General Senses Receptors and Receptive Fields 受體 Figure 9-1

The General Senses Pain Definitions Nociceptors痛覺感受器—Receptors for tissue damage to lead to the sensation of pain Fast (prickling) pain—Localized pain carried quickly to the CNS on myelinated axons Slow (burning) pain—Generalized pain carried on slow unmyelinated axons Referred pain轉移痛—Perception of pain in a part of the body not actually stimulated Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The General Senses Referred Pain Figure 9-2

The General Senses Temperature Thermoreceptors detect temperature change Free nerve endings Found in dermis, skeletal muscle, liver, hypothalamus Fast adapting (adaptation) Cold receptors greatly outnumber warm receptors Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The General Senses Touch, Pressure, and Position Mechanoreceptors機械性感受器—Receptors that respond to physical distortion of their cell membranes. Tactile觸覺 receptors—Sense touch, pressure, or vibration Baroreceptors壓覺—Sense pressure changes in walls of blood vessels, digestive organs, bladder, lungs Proprioceptors巴式感受器—Respond to positions of joints and muscle Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The General Senses Tactile Receptors Fine touch or pressure receptors Highly detailed information about a stimulus Crude touch or pressure receptors Poorly localized information about a stimulus Important types: root hair plexus毛根叢 tactile disks精細觸覺感受器 tactile corpuscles精細觸覺和壓覺感受器 lamellated corpuscles大型感受器 Ruffini corpuscles壓力和紐力感受器 Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Tactile Receptors in the Skin The General Senses Tactile Receptors in the Skin Figure 9-3

The General Senses Baroreceptors Provide pressure information essential for autonomic regulation Arterial blood pressure Lung inflation Digestive coordination Bladder fullness Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The General Senses Proprioceptors本體感覺受器 Monitor joint angle, tension in tendons and ligaments, state of muscular contraction Include: Muscle spindles Golgi tendon organs Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The General Senses Chemical Detection Chemoreceptors化學受器 respond to chemicals dissolved in body fluids that surround them and monitor the chemical composition of blood and tissues Chemicals that can be sensed include: Carbon dioxide Oxygen Hydrogen ion Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Smell Olfactory Organs嗅覺器官 Olfactory epithelium嗅覺上皮 Olfactory receptor cells Neurons sensitive to odorants Supporting cells Basal (stem) cells Olfactory glands Mucus-secreting cells

The Special Senses—Smell The Olfactory Pathways Axons from olfactory receptors penetrate cribriform plate of ethmoid bone Synapse in olfactory bulb Olfactory tract projects to: Olfactory cerebral cortex Hypothalamus Limbic System The Olfactory Organs Figure 9-6(b)

The Special Senses—Taste Taste (Gustatory) Receptors味覺 Taste buds味蕾 Found within papillae on tongue, pharynx, larynx Contain gustatory cells, supportive cells Taste hairs (cilia) extend into taste pores Sense salt, sweet, sour, bitter Also sense umami味精, water Synapse in medulla oblongata Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Taste Gustatory Receptors Figure 9-7(a)

The Special Senses—Taste Gustatory Receptors Figure 9-7(b)

The Special Senses—Taste Gustatory Receptors Figure 9-7(c)

The Special Senses—Vision Accessory Structures of the Eye Eyelids (palpebra) 眼瞼and glands Superficial epithelium of eye Conjunctiva結膜 Lacrimal淚 apparatus Tear production and removal Extrinsic eye muscles Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision The Lacrimal Apparatus Lacrimal gland淚腺 produce tears Bathe conjunctiva Contain lysozyme to attack bacteria Tears drain into nasal cavity Pass through lacrimal canals淚管, lacrimal sac淚囊, nasolacrimal duct鼻淚管 Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision The Accessory Structures of the Eye Figure 9-8(a)

The Special Senses—Vision The Accessory Structures of the Eye Figure 9-8(b)

The Special Senses—Vision Extrinsic Eye Muscles Move the eye Six muscles cooperate to control gaze Superior上 and inferior下 rectus直 Lateral外 and medial 內rectus Superior上 and inferior下 oblique斜

The Special Senses—Vision Fibrous tunic纖維膜 Sclera捷膜 Dense fibrous connective tissue “White of the eye” Cornea角膜 Transparent Light entrance Vascular tunic血管層 Iris虹膜 Boundary between anterior and posterior chambers Ciliary body捷狀体 Ciliary muscle and ciliary process Attachment of suspensory ligaments Choroid脈絡膜 Highly vascular Neural tunic(Retina)網膜層 Outer pigmented part Absorbs stray light Inner neural part Detects light Processes image Communicates with brain

The Special Senses—Vision Functions of the Vascular Tunic Provide a route for blood vessels Control amount of light entering eye Adjust diameter of pupil瞳孔 Secrete and absorb aqueous humor Adjust lens水晶體 shape for focusing Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision The Sectional Anatomy of the Eye Figure 9-10(b)

The Special Senses—Vision The Pupillary Muscles Figure 9-11

The Special Senses—Vision The Sectional Anatomy of the Eye Figure 9-10 (c)

The Special Senses—Vision Organization of the Retina Photoreceptor layer Bipolar cells雙極細胞 Amacrine無足細胞, horizontal cells水平細胞 modify signals Ganglion cells節細胞 Optic nerve (CN II) Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision Retinal Organization Figure 9-12(a)

The Special Senses—Vision Retinal Organization Figure 9-12(b)

The Special Senses—Vision Retinal Organization Figure 9-12(c)

The Special Senses—Vision The Aqueous Humor Secreted by ciliary processes into posterior chamber Flows into anterior chamber Maintains eye shape Carries nutrients and wastes Reabsorbed into circulation Leaves at canal of Schlemm許萊母氏管 Excess humor leads to glaucoma青光眼 Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision Eye Chambers and the Circulation of Aqueous Humor Figure 9-14

The Special Senses—Vision The Lens Supported by suspensory ligaments Built from transparent cells Surrounded by elastic capsule Lens and cornea focus light on retina Bend light (refraction) Accommodation changes lens shape Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision Focal Point, Focal Distance, and Visual Accommodation Figure 9-15(a)

The Special Senses—Vision Focal Point, Focal Distance, and Visual Accommodation Figure 9-15(b)

The Special Senses—Vision Focal Point, Focal Distance, and Visual Accommodation Figure 9-15(c)

The Special Senses—Vision Focal Point, Focal Distance, and Visual Accommodation Figure 9-15(d)

The Special Senses—Vision Focal Point, Focal Distance, and Visual Accommodation Figure 9-15(e)

The Special Senses—Vision Image Formation Figure 9-16(a)

The Special Senses—Vision Image Formation Figure 9-16(b)

The Special Senses—Vision Visual Abnormalities Figure 9-17(a)

The Special Senses—Vision Visual Abnormalities Figure 9-17(b)

The Special Senses—Vision Visual Abnormalities Figure 9-17(c)

The Special Senses—Vision Visual Abnormalities Figure 9-17(d)

The Special Senses—Vision Visual Abnormalities Figure 9-17(e)

The Special Senses—Vision Visual Physiology Photoreceptors—Cells specialized to respond to photons, packets of light energy Two types of photoreceptors Rods Highly sensitive, non-color vision In peripheral retina Cones Less sensitive, color vision Mostly in fovea, center of macula lutea Site of sharpest vision Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision Photoreceptor Anatomy Outer segment Discs with visual pigments Light absorption by rhodopsin視紫 Opsin視蛋白酶 + retinal視網膜 Inner segment Synapse with bipolar cell Control of neurotransmitter release Effect on bipolar cells Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

The Special Senses—Vision The Structure of Rods and Cones Figure 9-19

The Special Senses—Vision The Visual Pathway Ganglion cells axon converge at optic disc Axons leave as optic nerve (CN II) Some axons cross at optic chiasm視神經交叉 Synapse in thalamus bilaterally Thalamic neurons project to visual cortex Located in occipital lobes Contains map of visual field

Equilibrium and Hearing Sensory Functions of the Inner Ear Dynamic equilibrium Static equilibrium Hearing Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing Anatomy of the Ear External ear外耳 Pinna (auricle)耳壳 External acoustic canal外耳道 Tympanic membrane (eardrum)鼓膜 Middle ear中耳 Auditory ossicles耳骨 Connect tympanic membrane to inner ear Auditory tube耳咽管 Connection to nasopharynx鼻咽管 Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing Anatomy of the Inner Ear Vestibule前庭 Membranous sacs Utricle球狀囊 Saccule橢圓囊 Receptors for linear acceleration, gravity Semicircular canal半規管with ducts Receptors for rotation Cochlea耳蝸 with cochlear duct耳蝸管 Receptors for sound Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing Receptors of the Inner Ear Hair cells毛細胞 Mechanoreceptors Stereocilia on cell surface Bending excites/inhibits hair cell Information on direction and strength of mechanical stimuli Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing The Anatomy of the Ear Figure 9-22

Equilibrium and Hearing The Structure of the Middle Ear Figure 9-23

Equilibrium and Hearing The Anatomy of the Ear Figure 9-24(a,b)

Equilibrium and Hearing The Anatomy of the Ear Figure 9-24(c) PLAY The Ear: Ear Anatomy

Equilibrium and Hearing Semicircular ducts Connect to utricle Contains ampulla with hair cells Stereocilia立體纖毛 contact cupola Gelatinous mass distorted by fluid movement Detects rotation of head in three planes Anterior, posterior, lateral ducts Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing Equilibrium (continued) Saccule球囊 and utricle橢圓囊 Hair cells cluster in maculae聽斑 Stereocilia contact otoliths耳石 (heavy mineral crystals) Gravity pulls otoliths Detect tilt of head Sensory axons in vestibular branch of CN VIII Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Head in horizontal position Figure 9-25(e) 1 of 4 Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing The Cochlea and the Organ of Corti Figure 9-26(a)

Equilibrium and Hearing The Cochlea and the Organ of Corti Figure 9-26(b)

Figure 9-27 1 of 7 Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing Auditory Pathways Hair cells excite sensory neurons Sensory neurons located in spiral ganglion Afferent axons form cochlear branch of vestibulocochlear nerve (CN VIII) Synapses in cochlear nucleus in medulla Neurons relay to midbrain Midbrain relays to thalamus Thalamus relays to auditory cortex (temporal lobe) in a frequency map Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings

Equilibrium and Hearing Pathways for Auditory Sensations Figure 9-28

Aging and the Senses Impact of Aging on Sensory Ability Gradual reduction in smell and taste sensitivity as receptors are lost Lens changes lead to presbyopia (loss of near vision) Chance of cataract increases Progressive loss of hearing sensitivity as receptors are lost (presbycusis) Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings