Physiology of Vestibular, Olfactory, and Gustatory Systems PDF

Equilibrium, Smell & Taste Nurfitri Bustamam, SSi, MKes, MPdKed. Learning Objectives Explain how the receptors in the semicircular canals detect rotational acceleration & how saccule & utricle detect linear acceleration List the major sensory inputs that provide the information that...

Equilibrium, Smell & Taste Nurfitri Bustamam, SSi, MKes, MPdKed. Learning Objectives Explain how the receptors in the semicircular canals detect rotational acceleration & how saccule & utricle detect linear acceleration List the major sensory inputs that provide the information that is synthesized in the brain into the sense of position space  Name the five major taste receptors & signal transduction mechanisms in these receptors  Outline the pathways by which impulses generated in taste receptors reach the insular cortex Nurfitri Bustamam 2 Learning Objectives  Describe the basic features of the neural elements in the olfactory epithelium & olfactory bulb  Describe signal transduction in odorant receptors  Outline the pathway by which impulses generated in the olfactory epithelium reach the olfactory cortex Nurfitri Bustamam 3  Equilibrium Mendeteksi percepatan linier: - utrikulus horizontal - sakulus vertikal Mendeteksi percepatan anguler: - canalis semisirkularis horizontal (lateral) sagital (anterior) vertikal frontal (posterior) Nurfitri Bustamam 4 Nurfitri Bustamam 5 Utriculus & Saculus Otoconia: 3-19 µm, if terlepas dari otolith membrane  abnormal deflection when head change position (benign paroxysmal positional vertigo/BPPV) Nurfitri Bustamam 6 Nurfitri Bustamam 7 Canalis Semisirkularis Nurfitri Bustamam 8 Canalis Semisirkularis Nurfitri Bustamam 9 Nurfitri Bustamam 10  (Ganong 2019) Nurfitri Bustamam 11 Nurfitri Bustamam 12 Nurfitri Bustamam 13 Nurfitri Bustamam 14 Nystagmus: refleks utk menjaga fiksasi penglihatan, tdd komponen lambat & cepat Nurfitri Bustamam 15  Nystagmus a) Komponen lambat (vestibulo-ocular-reflex)/VOR Reseptor: vestibuler Aferen: N.VIII Pusat: oculomotor nuclei Eferen: N.III, N.IV, N.VI Efektor: otot penggerak bola mata (berlawanan arah rotasi) b) Komponen cepat (stretch reflex) Otot bola mata teregang muscle spindle kontraksi (searah rotasi) Nystagmus umumnya horizontal, tetapi dpt pula vertikal (kepala miring) atau berputar (kepala tertunduk) Nurfitri Bustamam 16 Nurfitri Bustamam 17 Nurfitri Bustamam 18 Nurfitri Bustamam 19 Caloric Stimulation Perbedaan suhu  konveksi  gerakan cupula  nystagmus & nausea Nurfitri Bustamam 20 Nurfitri Bustamam 21 Caloric Stimulation Water 40oC (warm) & 30oC (cold) in external auditory meatus Temperature difference  convection currents in endolymph  motion of cupula Healthy subjects  COWS (Cold water nystagmus is Opposite side, Warm water nystagmus is Same side) Unilateral lession in vestibular pathway  nystagmus or absent on the side of lesion Nurfitri Bustamam 22 Spatial Orientation Nurfitri Bustamam 23 Nurfitri Bustamam 24 Nurfitri Bustamam 25  Motion Sickness  conflicting information into vestibuler & other sensory systems Nurfitri Bustamam 26  Aviation Gymnastic Equipment Nurfitri Bustamam 27  BARANY ROTATION TEST Nurfitri Bustamam 28  BARANY ROTATION TEST Barany introduced a routine clinical test that involves observation of the post-rotatory responses after a patient is spun around several times in specially designed swivel chair. post-rotatory nystagmus, abnormanalities in standing & walking, falling, and a past-pointing error can be obeserved Nystagmus The eyes remain fixed on their original point of focus, so that they must diverge slowly towards the left to compensate for rotation of the body to the right. When the limit to which the eyes can be rotated laterally is exceeded, they snap quickly back to the right and select a new point of fixation. These alternate slow and quick movements of the eyes are called nystagmus. Nurfitri Bustamam 29  Falling The subject would be expected to fall towards the side of flexion, which in the case of post-rotatory reflexes would be in the same direction as the rotation. However, since proprioceptors in the trunk & limbs are still functioning, he may over-correct this tendency and stagger over towards the extended side. Past Ponting Error Occurs when the subject with eyes closed is instructed to repeatedly extend his arm to touch an object directly in front of him, successive movement will deviate in the direction opposite to his sensation of vertigo. (Wiggers 1955: 171-174) Nurfitri Bustamam 30 Nurfitri Bustamam 31  Vertigo: sensasi berputar tanpa ada putaran yg sesungguhnya Meniere’s disease: fluid imbalance in inner ear (vestibular apparatus & cochlea), simptom: vertigo, loss of hearing, ringing in the ears Nurfitri Bustamam 32 TASTE = GUSTATION Nurfitri Bustamam 33  Taste bud tdd: - basal cells - Sel tipe 1&2 (sustentacular cells) - Sel tipe 3 (gustatory receptor cells) Nurfitri Bustamam 34  Sel tipe 1, 2 & 3 memp. microvili yg menjulur ke pori pengecap (taste pore) Tiap taste bud diinervasi 50 serat saraf Tiap serat saraf menerima input dari  5 taste bud Sel basal berdiferensiasi mjd reseptor yg baru, reseptor diganti secara continue, dg half life 10 hari  continuous replacement Ada 10.000 taste bud pada dewasa muda dan jumlahnya akan berkurang sejalan dg usia Jika n. sensorik dipotong, taste bud yg diinervasinya akan berdegenerasi. Namun, jika saraf tsb beregenerasi sel-sel di sekitarnya akan mjd taste bud Taste bud (fungiform & vallate papillae) tdpt pd mucosa epiglottis, palate, pharynx & lidah Nurfitri Bustamam 35  Physiology of Taste Pd manusia ada 5 basic taste: sweet, sour, bitter, salt Taste bud tsb tdk berbeda dlm histologi Asam: - H+ menstimulasi reseptor - as.organik lbh terasa asam dari as. mineral (diduga karena asam organik lbh cepat masuk ke sel) Asin: - Na+ sel - beberapa senyawa organik juga terasa asin Manis - sukrosa, maltosa, glukosa, glyseral, as. aspartat - sacharin & aspartane (pemanis buatan) Nurfitri Bustamam 36  Pahit: quinine sulfate, nicotine, morphine, caffeine, strychnine, magnesium, amonium & calcium Umami Japanese scientists  “meaty” or “savory” (gurih) Stimulated by L-glutamate and nucleotides Monosodium glutamate (MSG), added to foods as a flavor enhancer, confers an umami taste to foods. Nurfitri Bustamam 37 Nurfitri Bustamam 38 Nurfitri Bustamam 39 (Constanzo 5th ed.) 40 Nurfitri Bustamam 41 Nurfitri Bustamam 42 Intensity discrimination: perbedaan konsentrasi hingga lbh dari 30% baru disadari Variation & after-effect PTC (Phenylthiocarbamide) pd populasi Caucasian: 70% merasakan asam + 30% tasteless Miraculin (taste modifier protein) makes acid taste sweet Nurfitri Bustamam 43 Nurfitri Bustamam 44 Nurfitri Bustamam 45  Tes waktu sirkulasi: op disuntik suatu zat timbul respons merasa pahit di lidah, mekanisme: zat di sirkulasi sel kelenjar ludah sekresi rasa pahit Nurfitri Bustamam 46  Taste pathways Serat saraf sensorik dari taste bud di: - 2/3 anterior lidah lewat n. VII - 1/3 posterior lidah lewat n. IX - di luar lidah lewat n. X Nurfitri Bustamam 47 Nurfitri Bustamam 48 Nurfitri Bustamam 49 Abnormalities in Taste Detection  Ageusia & Hypogeusia  Dysgeusia/parageusia  Altered in serotonin & Norepinephrin level (anxiety /depresion altered taste threshold  Zinc or vit B3 deficiency  Damage glossopharyngeal nerve  Neurological disorders: multiple sclerosis, bell palsy  Poor oral hygiene, smoking  Aging, drug: captoptril, cisplatin  Theraphy: improved oral hygiene & zinc supplementation Nurfitri Bustamam 50  Supertaster: increased number of fungiform papillae on their tounge Nurfitri Bustamam 51  SMELL  Flavor (cita rasa)  Trigger the memory  Aroma theraphy  Conditional Reflex (Refleks bersyarat) Nurfitri Bustamam 52  Macrosmatic animals: dog Microsmatic animals: human (area 10 cm2 ) Olfactory mucous membran mengandung supporting cells, progenitor, 10-20 juta reseptor, mucus (dihslkan oleh Bowman’s gland) Fisiologi penciuman: reseptor hy berespons dg zat yg bersentuhan dg olfactory epitelium & larut dlm mucus Nurfitri Bustamam 53 Nurfitri Bustamam 54 Nurfitri Bustamam 55 Nurfitri Bustamam 56 Nurfitri Bustamam 57  Signal Transduction Nurfitri Bustamam 58 Nurfitri Bustamam 59  (Constanzo 5th ed.) Nurfitri Bustamam 60 Pathway Nurfitri Bustamam 61 Nurfitri Bustamam 62  Ambang reseptor thd suatu zat berbeda-beda, manusia dpt membedakan 2000-4000 jenis bau Kemampuan manusia membedakan intensitas bau kurang (berbeda 30% baru disadari) Nurfitri Bustamam 63  Arah bau ditentukan oleh waktu molekul odoriferus ke nostril Strong odors adalah zat yg relatif tinggi kelarutannya pd air & lemak Odorant binding protein: concentrate & transfer molekul odoriferous - N I: bau enak  salivasi, bau tidak enak  nausea - stimulasi ujung saraf bebas  N V: inisiasi bersin, lakrimasi, dan menahan napas Sniffing (meningkatkan aliran udara ke reseptor) Adaptasi cepat Nurfitri Bustamam 64 Abnormalities in Odor Detection  Anosmia: inability to smell  Hyposmia/hypesthesia: diminished olfactory sensitivity  simple nasal congestion/nasal polyps,  damage olfactory nerve due to fractures of the cribiform plate/head trauma,  tumors (neuroblastoma/meningiomas)  respiratory tract infections Nurfitri Bustamam 65 Abnormalities in Odor Detection  Hyperosmia: oversensitive to smell pregnant women  Dysosmia: distorted sense of smell  sinus infections, partial damage olfactory nerve, poor dental hygiene  THERAPHY  Antibiotic  Surgery  Corticosteroid Nurfitri Bustamam 66  The Smell Survey by A.N. Gilbert & C.J. Wysocki. National Geographic 1987; 172(4): 514-525 Nurfitri Bustamam 67 Tujuan: mdptkan informasi fisiologi & perilaku manusia 6 sampel: - adrostenone (sweat) - isoamyl acetate (banana) - galaxolide (musk) - eugenol (cloves) - mercaptans (gas) - rose (floral) Could you smell it? Did you correctly identify odor? Ada 1,5 juta data yg masuk dirandom 26.200 (US) & 100.000 (di luar US) Nurfitri Bustamam 68  di US 35% subjek anosmia thd androstenone, 29% anosmia thd galaxolide  Kemampuan menghidu pd wanita lbh baik dari pria  Lingkungan (geografis & tempat bekerja) mempengaruhi kemampuan menghidu Nurfitri Bustamam 69 Nurfitri Bustamam 70 - merokok mempengaruhi kemampuan menghidu - kemampuan menghidu bau tdk enak dari mercaptant (gas odor) dipengaruhi usia Nurfitri Bustamam 71 Terima Kasih