3 - Signals and Perception Flashcards
3 definitions of sensation
detection of stimulus’s signal
physical feeling due to body contact with something
different modalities
define transduction
converting sensory signal to electrical one at sensory receptors to be carried to the spinal cord (and brain)
what is sensory transduction
sensory stimuli converted to receptor potentials
what does not enough exposure to sensations do during nervous system development
leads to smaller brain and larger ventricles
perception depends on what two things
previous experience
attention
key chain of perception
sensory signal sensory receptor brain/spinal cord perception perceptual understanding behavioural response
what is sensation-perception
brain interprets a stimulus and perception of this stimulus can change
3 dimensions of sound
pitch/frequency
loudness
timbre
define loudness
degree to which condensations and refractions differ from each other
3 components of the outer ear
pinna concha and meatus/auditory canal
how does the outer ear provide protection
skin cells move outwards acidic earwax is antibacterial/fungal oily outward hairs preventing insects
what about the auditory canal protects the tympanic membrane
shape
depth
rigidity
how are signals close to human speech amplified
closed tube resonator which is a space for sound waves to echo and is open at the anti-node and closed to the tymp mem
4 components of the middle ear
tympanic membrane
ossicles
malleus
stapes
role of the ossicles
bones to join eardrum to cochlea for energy transmission
role of the malleus
a hammer transmitting vibrations through the incus and stapes to the cochlea
what is the cochlea and what does it do
inner ear part filled with fluid and connects receptors
how does the cochlea increase the signal’s amplification
less area from the tymp mem to the cochlea, increasing pressure
where is perilymph and endolymph
perilymph in outer corridor of cochlea
endolymph in Organ of Corti in the cochlea
what 3 things does the Organ of Corti have
tectorial membrane
auditory hair cells on the
basilar membrane
where are the stereocilia and what happens when there are sound waves
endolymph
tectorial and basal membrane move so stereocilia bend towards the tallest hair
what happens after the stereocilia bend
mechanically-gated Na+ channels open, Na+ moves in, depolarisation, Ca2+ channels open, Ca2+ enters, glutamate released by exocytosis
what happens when glutamate is released in the Organ of Corti
binds to AMPA receptors in the auditory nerve, producing an action potential
how is there protection in the inner
tensor tympani and stapedius muscles contract if there’s a loud sound so ossicles lock preventing sound transmission