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PENGLIHATAN PENGLIHATAN ( ( VISION VISION VISION VISION VISION VISION VISION VISION ) YETTY MACHRINA YETTY MACHRINA MILAHAYATI DAULAY MILAHAYATI DAULAY MILAHAYATI DAULAY MILAHAYATI DAULAY DEPARTEMEN FISIOLOGI DEPARTEMEN FISIOLOGI FAKULTAS KEDOKTERAN FAKULTAS KEDOKTERAN UNIVERSITAS SUMATERA UTARA UNIVERSITAS SUMATERA UTARA

PENGLIHATAN (( VISION )) - ocw.usu.ac.idocw.usu.ac.id/course/download/1110000121-special-senses-system/s… · Mata sebagai sumber informasi awal Apa-apa yang kita lihat dapat terekam

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  • PENGLIHATAN PENGLIHATAN ( ( VISION VISION VISION VISION VISION VISION VISION VISION ))

    YETTY MACHRINAYETTY MACHRINA

    MILAHAYATI DAULAYMILAHAYATI DAULAYMILAHAYATI DAULAYMILAHAYATI DAULAY

    DEPARTEMEN FISIOLOGIDEPARTEMEN FISIOLOGI

    FAKULTAS KEDOKTERAN FAKULTAS KEDOKTERAN

    UNIVERSITAS SUMATERA UTARAUNIVERSITAS SUMATERA UTARA

  • SPESIAL SENSE SPESIAL SENSE (Indra Khusus)(Indra Khusus)

    VISIONVISION

    HEARINGHEARING HEARINGHEARING

    SMELLSMELL

    TASTETASTE

    EQUILIBRIUMEQUILIBRIUM

  • Mata sebagai sumber informasi

    awal

    Apa-apa yang kita lihat dapat

    terekam sebagai satu memori

  • PROSES PENGLIHATANPROSES PENGLIHATAN

    Cahaya masuk melalui pupil refleks pupil

    Proses refraksi proses akomodasi

    Photoreseptor (retina)Photoreseptor (retina)

    N. Opticus

    thalamus

    Corteks cerebri area 17 Dan 18 (lobus occipitalis)

  • Function of the Major Componen Of Function of the Major Componen Of the Eyethe Eye

    EyelidsEyelids

    EyelashesEyelashes

    TearsTears

    CorneaCornea

    PupilPupil

    LensaLensa

    Vitreous HumorVitreous Humor

    ScleraSclera CorneaCornea

    Aqueous HumorAqueous Humor

    IrisIris

    ConjunctivaConjunctiva

    Cilliary BodyCilliary Body

    Suspensory Suspensory LigamentLigament

    ScleraSclera

    ChoroidChoroid

    RetinaRetina

    FoveaFovea

    Optic NerveOptic Nerve

    Optic DiscOptic Disc

  • TEARSTEARS

    Tears are produced Tears are produced continously by lacrimal continously by lacrimal glandgland

    Lacrimal gland lying at the Lacrimal gland lying at the upper lateral corner of upper lateral corner of upper lateral corner of upper lateral corner of under the eyelidsunder the eyelids

    Lacrimal gland innervate by Lacrimal gland innervate by ANS (parasympatis)ANS (parasympatis)

    Tears thTears thrrough out each ough out each time eyelids closetime eyelids close

  • Tears Flow

    Lacrimal gland

    Ductus Lacrimal

    Anterior surface

    Lacrimal canal

    Ductus nasolacrimalis

    Inferior concha

    Cavum nasi

  • Tears Function Tears Function

    ProtectionProtection

    Keep cornea wetKeep cornea wet Keep cornea wetKeep cornea wet

    Protect the eye Protect the eye from infectionfrom infection

  • AQUEOUS HUMORAQUEOUS HUMOR

    Aqueous Humor is clear liquid material Aqueous Humor is clear liquid material produced about 5ml/day by capillary produced about 5ml/day by capillary network witnetwork withinhin cilliary bodycilliary body

    It nourishes the cornea and lensaIt nourishes the cornea and lensa It nourishes the cornea and lensaIt nourishes the cornea and lensa It flows through the pupil and fills tha It flows through the pupil and fills tha anterior chamber. Drains into a venous anterior chamber. Drains into a venous canal between iris and cornea (canal of canal between iris and cornea (canal of schlemm) , enters the bloodschlemm) , enters the blood

    If there is a blokage in the drainage canal, If there is a blokage in the drainage canal, the excess will accumulate in the anterior the excess will accumulate in the anterior cavity, causing the pressure to rise call cavity, causing the pressure to rise call

  • PERGERAKAN OTOT MATAPERGERAKAN OTOT MATA

    M.Rektus

    M.Rektus superior M. Obliq inf

    M.Rektus

    medial

    M. Rektus inferior M. Obliq sup

    M. Rektus lat

  • Kerja otot luar mataKerja otot luar mata

    OtotOtot Kerja primerKerja primer Kerja sekunderKerja sekunder

    Rektur lateralRektur lateral

    Rektus medialisRektus medialis

    Rektus superiorRektus superior

    AbduksiAbduksi

    AdduksiAdduksi

    ElevasiElevasi

    Tidak adaTidak ada

    Tidak adaTidak ada

    Adduksi, intorsiAdduksi, intorsiRektus superiorRektus superior

    Rektus inferiorRektus inferior

    Obikus superiorObikus superior

    Oblikus inferiorOblikus inferior

    ElevasiElevasi

    DepresiDepresi

    IntorsiIntorsi

    EkstorsiEkstorsi

    Adduksi, intorsiAdduksi, intorsi

    Adduksi, ekstorsiAdduksi, ekstorsi

    Depresi, abduksiDepresi, abduksi

    Elevasi, abduksiElevasi, abduksi

  • Persarafan Otot Pergerakan Persarafan Otot Pergerakan MataMata

    MM. Obliqus inferior . Obliqus inferior

    M. Rektus M. Rektus superiorsuperior

    M. Rektus M. Rektus inferiorinferior

    N. III (okulomotorius)

    M. Rektus M. Rektus inferiorinferior

    M. Rektus M. Rektus medialmedial

    M. Obliqus superiorM. Obliqus superior

    M. Rektus M. Rektus laterallateral

    N. IV (trokhlearis)

    N. VI ( abducens)

  • Reflex pupil constriction occurs in bright light to Reflex pupil constriction occurs in bright light to decrease the amount of light entering the eye decrease the amount of light entering the eye The circular muscle contract (become shorten), The circular muscle contract (become shorten), pupil gets smallerpupil gets smaller

    Bright light Bright light circular muscle contractcircular muscle contractmiosis miosis

    Reflex pupil dilatasion occurs in dim light to Reflex pupil dilatasion occurs in dim light to allow the entrance of more light. The radial allow the entrance of more light. The radial muscle contract, pupil size is increasemuscle contract, pupil size is increase

    Dim light Dim light radial muscle contractradial muscle contractdilatasidilatasi

  • PUPIL REFLEXPUPIL REFLEX

    Pupil is controled by Pupil is controled by irisiris

    Iris contains 2 set of smooth muscle Iris contains 2 set of smooth muscle network :network :network :network :

    1.1. Circular muscle (ringlike fashion Circular muscle (ringlike fashion within the iris)within the iris)

    2.2. Radial muscle (like bicycle spokes)Radial muscle (like bicycle spokes)

  • Iris muscle is controlled by autonomic nervous Iris muscle is controlled by autonomic nervous system.system.Parasympatis innervate the circular muscleParasympatis innervate the circular muscleSympatis innervate the radial muscleSympatis innervate the radial muscle

    If light directed into the pupil, pupil will constrict If light directed into the pupil, pupil will constrict If light directed into the pupil, pupil will constrict If light directed into the pupil, pupil will constrict and pupil the also other eye (consensual light and pupil the also other eye (consensual light reflex). It because optic nerve fibers bring reflex). It because optic nerve fibers bring impuls to the optic nerve near the lateral impuls to the optic nerve near the lateral genuculate nucleus genuculate nucleus midbrainmidbrain ipsilateral ipsilateral EdingerEdinger--Westphal nucleus and contralateral Westphal nucleus and contralateral EdingerEdinger--westphal, cilliary gangglion N.III, westphal, cilliary gangglion N.III, sebagian dari ganglion ke ciliary bodysebagian dari ganglion ke ciliary body

  • ORGAN REFRACTIEORGAN REFRACTIE

    1.1. CorneaCornea

    2.2. LensaLensa

    The refractive ability of persons corneaThe refractive ability of persons corneaThe refractive ability of persons corneaThe refractive ability of persons cornea

    Always constan because the curvature ofAlways constan because the curvature of

    cornea never change. cornea never change.

    The refactive ability of the lens can be The refactive ability of the lens can be adjusted by chaging its curvature as adjusted by chaging its curvature as needed for near or far visionneeded for near or far vision

  • ACCOMODATIONACCOMODATION

    The ability to adjustThe ability to adjust

    Regulated by the cilliary muscleRegulated by the cilliary muscle

    Cilliary muscle is circular ring of smooth muscle Cilliary muscle is circular ring of smooth muscle attached to the lens by suspensory ligamentattached to the lens by suspensory ligament

    Normal eye :Normal eye :Normal eye :Normal eye :

    -- m. cilliary relax, suspensory lig. Is pulled, m. cilliary relax, suspensory lig. Is pulled, lens is flat for far vision (lens is flat for far vision (simpatissimpatis))

    -- m. cilliary contract, slackening the tension m. cilliary contract, slackening the tension in suspensory lig, lens is more convex and in suspensory lig, lens is more convex and stonger for near vision (stonger for near vision (parasimpatisparasimpatis))

  • Anatomy PemfokusanAnatomy Pemfokusan 233

  • PHOTORESEPTOR (PHOTORESEPTOR (retinaretina))

    Retina consist of three Retina consist of three layers :layers :

    1. outer segment (close to 1. outer segment (close to choroid)choroid)

    rodrodrodrod

    conecone

    2. 2. midlemidle segmensegmen

    Bipolar neuronBipolar neuron

    3. inner segment3. inner segmentGanglion cellGanglion cell

  • Ganglion axons Ganglion axons membentuk optik nervemembentuk optik nerve

    Titik di retina tempat keluarnya saraf Titik di retina tempat keluarnya saraf optikus dan lewatnya pembuluh darah optikus dan lewatnya pembuluh darah disebut disebut Diskus optikus (bintik buta)Diskus optikus (bintik buta)disebut disebut Diskus optikus (bintik buta)Diskus optikus (bintik buta)

    PadaPada foveafovea, cahaya yang masuk langsung , cahaya yang masuk langsung mencapai fotoreseptor tidak melalui lapisan mencapai fotoreseptor tidak melalui lapisan ganglion dan bipolar ok lapisan ganglion ganglion dan bipolar ok lapisan ganglion

    dan bipolar tertarik ke sampingdan bipolar tertarik ke samping

  • Pada fovea hanya ada sel Pada fovea hanya ada sel kerucut, sehingga titik ini kerucut, sehingga titik ini berfungsi untuk penglihatan berfungsi untuk penglihatan tajam.tajam.

    Daerah tepat disekitar fovea Daerah tepat disekitar fovea disebut disebut makula luteamakula lutea

    Pada makula lutea, sel Pada makula lutea, sel --sel sel Pada makula lutea, sel Pada makula lutea, sel --sel sel kerucut banyak, sehingga kerucut banyak, sehingga ketajaman daerah ini tinggi. ketajaman daerah ini tinggi. Namun tidak lebih besar Namun tidak lebih besar daripada fovea ok terdapat daripada fovea ok terdapat lapisan bipolar dan sellapisan bipolar dan sel--sel sel ganglion diatas makula.ganglion diatas makula.

  • OUTER SEGMEN OUTER SEGMEN

    Banyak mengandung fotopigmenBanyak mengandung fotopigmen

    Terdiri atas protein enzimatik yaitu opsin yang Terdiri atas protein enzimatik yaitu opsin yang berikatan dengan retinen (derivat vitamin A, berikatan dengan retinen (derivat vitamin A, red).red).red).red).

    Retinen = 1 di sel batang Retinen = 1 di sel batang

    3 di masing3 di masing--masing sel kerucut masing sel kerucut (sel merah,hijau, biru)(sel merah,hijau, biru)

    FOR COLOR VISIONFOR COLOR VISION

  • Photoreceptor Activity in the DarkPhotoreceptor Activity in the Dark

    The plasma membrane chemically channel of The plasma membrane chemically channel of photoreceptor respond to internal second photoreceptor respond to internal second massenger, massenger, cGMP. cGMP. BindBindiing cGMP + Nang cGMP + Na++

    channels keeps them open.channels keeps them open.

    When the is absence(stimulation), concentration When the is absence(stimulation), concentration of cGMP higher of cGMP higher NaNa++ channel open.channel open.of cGMP higher of cGMP higher NaNa++ channel open.channel open.

    Passive resultant inward NaPassive resultant inward Na++leak depolarize the leak depolarize the photoreseptor photoreseptor spread to synapitic terminal spread to synapitic terminal (where the photoreceptors neurotransmitter is (where the photoreceptors neurotransmitter is trored) trored) synaptic terminal voltage gated synaptic terminal voltage gated channels open channels open CaCa2+2+ entry entry trigger release of trigger release of neurotransmitterneurotransmitter from the synapticfrom the synaptic

  • Inhibitory neurotransmitter that srecreted

    by amacrine cells are gamma-

    aminobutyric acid, glycine, dopamine, aminobutyric acid, glycine, dopamine,

    acetylcholine, dolamine

    Photoreceptor inhibited of their adequate Photoreceptor inhibited of their adequate stimulus (hyperpolarized by light).stimulus (hyperpolarized by light).

    Excited absence of stimulation (depolarized Excited absence of stimulation (depolarized by darkness)by darkness)

  • No light

    Concentration cGMP

    Na+channels open in outer segmen

    Membran depolarization

    Spread to the terminal synaptic

    Ca2+ channels open

    Release neurotransmitter ((inhibitory neurotransmitter)

    Bipolar cells inhibited

    No action potential in ganglion cell

    No action potential propagation to visual cortex

  • Light

    Activation o fotopigment (rod and cone)

    Activation of transducin (G protein)

    cGMP

    Na+ channel closure

    Membran hyperpolarizasion (receptor potential)

    Spread to the terminal synaps

    Closure ca2+ channels

    Release inhibitory neurotrasnmitter

    Bipolar cell uninhibited

    Graded potential change in bipolar cell

    Action potential in ganglion cell

    Visual cortex in the occipital lobe of the brain

  • Benda (memantulkan cahaya)Benda (memantulkan cahaya)cornea cornea lensa lensa convergensi cahaya convergensi cahaya bayangan jatuh tepat di bayangan jatuh tepat di retina (fovea) retina (fovea) aktivasi fotopigmen aktivasi fotopigmen a a aktivasi transducin aktivasi transducin cGMPcGMP saluran Nasaluran Na++

    tertutup tertutup hyperpolarisasi membran hyperpolarisasi membran CaCa2+2+tertutup tertutup Penghambatan pelepasan Penghambatan pelepasan CaCa tertutup tertutup Penghambatan pelepasan Penghambatan pelepasan Neurotransmitter Neurotransmitter action potential action potential bipolar cell bipolar cell graded potensial pada cell ganglion graded potensial pada cell ganglion N. N. Opticus Opticus Optic disc Optic disc chiasma opticum chiasma opticum tractus geniculatus lateral di thalamus tractus geniculatus lateral di thalamus lobus lobus occipitalis area 17 occipitalis area 17 diasosiakan ke area 18diasosiakan ke area 18

  • Kiasma optikumKiasma optikum(Optic chiasma)(Optic chiasma)

    238

  • Visual deficits with Visual deficits with specific lesionsspecific lesions

    Leftt optic Leftt optic nervenerve

    Left eyeLeft eye Right eyeRight eye

    Optic Optic Optic Optic chiasmchiasm

    Left optic Left optic tract (or tract (or radiation)radiation)

  • VISUAL ADAPTATIONVISUAL ADAPTATION

    DARK ADAPTATIONDARK ADAPTATION

    -- Break down of photopigment during Break down of photopigment during exposure of sunlight fremendously exposure of sunlight fremendously exposure of sunlight fremendously exposure of sunlight fremendously decreases photoreceptor sensitivitydecreases photoreceptor sensitivity

    --As a result, the sensitivity of our eyes As a result, the sensitivity of our eyes gradually increase gradually increase u can see in the u can see in the darkdark

  • LIGHT ADAPTATIONLIGHT ADAPTATION

    As some of photopigment are rapidly As some of photopigment are rapidly brokendown by intense light, the brokendown by intense light, the brokendown by intense light, the brokendown by intense light, the sensitivsensitivIIty of the eye decreases and ty of the eye decreases and normal contras can once again be normal contras can once again be detected.detected.

  • CCOOLLOORR VISIONVISION

    Cone type = green, blue, redCone type = green, blue, red

    A wave length perceived as blue excite blue A wave length perceived as blue excite blue cone maximally does not stimulate red or cone maximally does not stimulate red or cone maximally does not stimulate red or cone maximally does not stimulate red or green cone at all.green cone at all.

    White is a mixture of all wavelength of lightWhite is a mixture of all wavelength of light

    Black is the absence of light.Black is the absence of light.

    We see the same color because we have We see the same color because we have the same type of cone.the same type of cone.

  • COLOR VISIONCOLOR VISION

    Color Color Percent maximum stimulationPercent maximum stimulation

    Visible spectrum

    Color Color perceivedperceived

    Percent maximum stimulationPercent maximum stimulation

    Red cones green cones blue conesRed cones green cones blue cones

    blueblue 00 0 0 100100

    greengreen 3131 67 3667 36

    redred 83 83 083 83 0

  • Visual fieldVisual field

    Visual field is field of view that can be Visual field is field of view that can be seen without moving the headseen without moving the head