Recommandé
Contenu connexe
Tendances
Tendances (20)
Similaire à OLFU_CAS SPECIAL SENSE_PART 1
Similaire à OLFU_CAS SPECIAL SENSE_PART 1 (20)
Dernier
Dernier (20)
OLFU_CAS SPECIAL SENSE_PART 1
- 1. Special Sense CHEMICAL SENSE: taste & smell THE EAR: hearing & balance THE EYE & VISION ARMIN PERPUSE, M.D Internal Medicine (Adult Disease Specialist) Department of Anatomy
- 2. Chemical Sense : TASTE & SMELL Receptors for smell and taste complement each other and respond to many of the same stimuli CHEMORECEPTORS • Receptors for taste and olfaction • Responds to chemicals in solution
- 3. OLFACTION -Sense of smell -Occurs in response to airborne molecules (odorants) OLFACTORY RECEPTOR CELLS: -400 functional receptors -Can bind multiple types of odorants -Neurons equipped with olfactory hairs. -These multiple combinations of odorants and receptors allows us to detect an estimated 10,000 different smells. -The threshold for the detection of odors is extremely low, so very few odorants bound to an olfactory neuron can initiate an action potential OLFACTORY HAIRS -long cilia that protrudes from nasal epithelium.
- 7. HYPOSMIA reduced ability to detect odors. ANOSMIA complete inability to detect odors. PAROSMIA change in the normal perception of odors, such as when the smell of something familiar is distorted, or when something that normally smells pleasant now smells foul. PHANTOSMIA sensation of an odor that is not present.
- 8. Taste buds and the Sense of Tast
- 9. TASTE? Taxare TO TOUCH TO ESTIMATE TO JUDGE Taste is mainly a function of the taste buds in the mouth, but it is common experience that one’s sense of smell also contributes strongly to taste perception.
- 14. PHANTOM TASTE PERCEPTION a lingering, often unpleasant taste HYPOGEUSIA Reduced ability to taste. AGUESIA Total loss of ability to taste. True taste loss, however, is rare. DYSGUESIA is a condition in which a foul, salty, rancid, or metallic taste sensation persists in the mouth. Accompanied by burning mouth syndrome, a condition in which a person experiences a painful burning sensation in the mouth. Although it can affect anyone, burning mouth syndrome is most common in middle- aged and older women.
Notes de l'éditeur
- The receptor for taste and olfaction are classified as CHEMORECEPTORS because they respond to chemicals in solution. Five types of taste receptors have been identified, but the OLFACTORY RECEPTORS (for smell) are believed to be sensitive to a much wider range of chemicals.
- OLFACTION -Sense of smell -Occurs in response to airborne molecules (odorants) -The only major sensation that is relayed directly to the cerebral cortex without passing through the thalamus OLFACTORY RECEPTOR CELLS: -400 functional receptors -Can bind multiple types of odorants -Neurons equipped with olfactory hairs. -continuously bathed by a layer of mucus that are secreted by underlying glands. -These multiple combinations of odorants and receptors allows us to detect an estimated 10,000 different smells. -The threshold for the detection of odors is extremely low, so very few odorants bound to an olfactory neuron can initiate an action potential OLFACTORY HAIRS -long cilia that protrudes from nasal epithelium.
- OLFACTION -Sense of smell -Occurs in response to airborne molecules (odorants) OLFACTORY RECEPTOR CELLS: -400 functional receptors -Can bind multiple types of odorants -Neurons equipped with olfactory hairs. -continuously bathed by a layer of mucus that are secreted by underlying glands. -These multiple combinations of odorants and receptors allows us to detect an estimated 10,000 different smells. -The threshold for the detection of odors is extremely low, so very few odorants bound to an olfactory neuron can initiate an action potential OLFACTORY HAIRS -long cilia that protrudes from nasal epithelium.
- When the olfactory receptors are stimulated by chemicals dissolved in the mucus, they transmit impulses along the OLFACTORY FILAMENTS, which are bundled axons of olfactory neurons that collectively make up the OLFACTORY NERVES (CN I). The CN I conducts the impulses to the olfactory cortex of the brain. Then Odor is interpreted. The olfactory pathways are closely tied into the limbic system (emotional-visceral part of the brain), thus olfactory impressions are long lasting and very much part of our memories and emotions.
- It includes the olfactory bulbs, hippocampus, hypothalamus, amygdala, anterior thalamic nuclei, fornix, columns of fornix, mammillary body, septum pellucidum, habenular commissure, cingulate gyrus, parahippocampal gyrus, limbic cortex, and limbic midbrain areas.[4] The limbic system supports a variety of functions including emotion, behavior, motivation, long-term memory, and olfaction.[5] Emotional life is largely housed in the limbic system, and it has a great deal to do with the formation of memories.
- The word TASTE comes from the latin word, TAXARE, which means “TO TOUCH, ESTIMATE, OR JUDGE” When we taste things we are in fact testing or judging our environment in an intimate way, and the sense of taste is considered by many to be most pleasurable of our special senses. The TASTE BUDS, or specific receptors for the sense of taste, are widely scattered in the oval cavity. Taste is mainly a function of the taste buds in the mouth, but it is common experience that one’s sense of smell also contributes strongly to taste perception.
- The dorsal tongue surface is covered with small peg-like projections or PAPILLAE The taste buds are found on the sides of the large round CIRCUMVALLATE PAPILLAE and on the top of the more numerous FUNGIFORM PAPILLAE. Taste buds are also distributed throughout other areas of the mouth and pharynx, such as on the palate, the root of the tongue and the epiglottis. FILIFORM PAPILLA Only papila has NO TASTE BUDS, only GUSTATORY CELLS (CELL that activates or stimulates your CN)
- 4 basic modalities of taste are sensed acutely in particluar regions of the tongue SWEET – tip BITTER – back SALTY – OVER MOST of the tongue SOUR – sides
- The most common taste disorder is phantom taste perception: a lingering, often unpleasant taste even though there is nothing in your mouth. People can also experience a reduced ability to taste sweet, sour, bitter, salty, and umami—a condition called hypogeusia [hy-po-GYOO-zee-a]. Some people can’t detect any tastes, which is called ageusia [ah-GYOO-zee-a]. True taste loss, however, is rare. Most often, people are experiencing a loss of smell instead of a loss of taste. In other disorders of the chemical senses, an odor, a taste, or a flavor may be distorted.Dysgeusia [dis-GYOO-zee-a] is a condition in which a foul, salty, rancid, or metallic taste sensation persists in the mouth. Dysgeusia is sometimes accompanied by burning mouth syndrome, a condition in which a person experiences a painful burning sensation in the mouth. Although it can affect anyone, burning mouth syndrome is most common in middle-aged and older women.