Senses Flashcards
How is emotional response to smell achieved
connection to limbic system
what is the location of receptors responsible for sense of taste
tongue, mouth and pharynx
What re the basic taste sensations
sour, bitter, sweet, salt, umami
What is the best place to recognise sweet and salty
tip of the tongue
What is the best place to recognise bitter and sour
posterior tongue and soft pallet
What nerves supply TASTE sensation to the tongue
A=> CN VII and P=> CN IX
What nerves supply sensation to the tongue
o Anterior 2/3 => branch of CNV
what nerves supply motor neurons to the tongue
CN XII
what are the bony labyrinths, what are they filled with
semicircular canal, cochlea, vestibule=> perilymph
what are the membranous labyrinths, what are they filled with
semicircular duct, cochlear duct sacs=> utricle and saccule; endolymph
What are the components of balance system
vestibule with utricle and saccule connected to semicircular canales and ducts
what are the three chambers of cochlea
scala media, vestibuli (upper) and tympani (lower)
what is the point of connection between scala tympani and vestibuli known as
helicotrema
What is the pathway for sound conduction in the inner ear
oval window => wave in the scala vestibuli=> wave in scala media => tectoral membrane moves=> movement of stereocilia and opening of mechanoreceptors=> K+ influx=> hair cell depolarisation => Ca influx in basal membrane => neurotransmitter release => hyperpolarisation by release of K+ to perilymph
What is the difference between perilymph and endolymph
endolymph is high in K (140 mM) and perilymph is low in K+
How is the pressure relapsed
through round window
how are different frequencies of sound detected
high frequency/pitch => stimulation form the base, low frequency stimulation from the apex
How is volume of the sound detected
greater number of action potentials in larger number of axons
what antibiotics are ototoxic
Aminoglycosides
what are causes of sensory hearing lose
age, loudness, genetic, rubella, drugs, trauma (temporal bone)
Name genetic defects associated with hearing loss
“o DFN – X-linked – Hair cell defect
o DFNA – Autosomal dominant – Tectorial membrane proteins
o DFNB – Autosomal recessive – Gap junction proteins
“
What is tympanometry
measurement of mobility of tympanic membrane
What is ABR
Auditory brainstem response => measures propagation of auditory stimulus in the brain via electrodes
what is otoacoustic emission
Emission of sound from the ear via efferent system
What is autography
plot of sensitivity against frequency
What is a name given to visual inspection of the ear
otoscopy
what is the pathway of neural conduction of sound
afferent neuron => cochlear nucleus=> decussation => superior olivary nucleus=> inferior colliculus=> medial geniculate body => primary auditory cortex of temporal bone
