sense organs: the ear the eye and other sense organs Flashcards
what is sound?
sound is a cycle of compressing and reacting molecules (think of slinky being stretched out and in)
- compression upper wave 0-180 degrees
- rarefraction lower wave 180-360 degrees
THE EAR
what are the two ways to describe a sound wave?
frequency and amplitude
what is frequency?
how often a cycle repeats itself and how often we get a full cycle
- all sound travels the same distance in given period of time
high frequencies = more squiggles and shorter wave length
low frequencies = less squiggles and longer wave length
how is frequency measured?
frequency is measured in hertz
hertz = cycles per second
what is amplitude?
how high the curves and waves go up - measures the intensity of sound
high intensity = high squiggles
low intensity = low squiggles
SOME HIGH FREQ AND HIGH AMP MIGHT NOT BE HEARABLE (how we can hear these sound but lupker cant)
how is amp/intensity measured?
measured in decibels
deca = 1/10th of something
- distance between two (10 and 20) and other two decibels (20 and 30) - not the same intensity
- goes up 10x the intensity between each pair (larger one 10x the lower one)
what is a phase?
specific point of time in a sound wave cycle
- measures where in the cycle is in the sound wave at a given point in time
what can happen when you have 2 pure tones with the same frequency? (in phase and out of phase)
in phase
- pressure changes are the same
- amplitude = sum of 2 tones
out of phase
- one reaches min at the same time the other reaches the max
- amplitude = difference between 2 tones
what is a wavelength?
distance between the first peak and the second peak (cycle)
- from max to min to max pressure
what is pitch?
whether we are expecting a high or lone not or tone
- normal ind hears 20 - 20 000 hertz
what is a pure tone?
sound that consists of one single frequency
- eg. tuning fork
what is timbre and complex sounds?
complex sounds that have additional psych properties
interaction of many diff sound waves of diff frequencies and phases that add and subtract from each other to create new sounds
- can tell diff when same note is being played on a diff instrument - each produce diff wave forms
what was Fourier’s idea about complex sounds?
any continuous periodic waveform can be represented as the sum of simple pure tones with right wavelengths, phases and amps
- eg. having diff glasses filled with diff amounts of water
ORGANS OF THE EAR
what is place theory?
for each freq of sound that enters ear activates diff parts of the basil membrane
basil membrane - place of max stim on membrane
1. low freq - travels longer and peaks later
2. high freq - travels shorter and peaks earlier
BETTER FOR HIGH PITCH
how to do a place theory test?
what is the frequency theory?
pitch is determined by how many times there are spike potentials traveling up the auditory nerve which indicates the frequency of the tone that was sent
eg. 1000h tone activates and vibrates the BM 1000 times
how do u do a freq theory test?
- present stream of white noise by pulsing on and off repeatedly
- activate all places in BM
- pulse BM certain amounts of time
- how ever many pulses there are will be the how many hertz of the tone or what the tome will be
what is the volley principle?
where neurons act in groups to be able to process higher pitch sounds
- when one is reloading or resting between spike potentials, the neighbouring will be firing
what are the colour after effects?
when u stare at one colour for a long time and move to a white area or sheet - you see the opposing colour to that original colour as the original colour is fatigued
what is the trichromatic theory?
underlines the idea that the 3 types of colour receptors that are visible on the spectrum that correspond to blue, green and red can produce any perception of a hue from our colour spectrum
- primary colours in light - blue, green and red all can combine to make all colours
- if all colours are used at the same intensity - WHITE LIGHT WILL BE PERCEIVED
what is opponent process theory?
idea that there are 4 primary colours which are yellow, blue, green and red in which they create 3 opposing systems including black and white
- blue and yellow
- red and green
- black and white
- only can detect one of the opposing colours at a time as one supresses the other
what is a dichromat?
ind who is deficient in the idea that one of their 3 cones do not work
- when ind is deficient in red or green - tend to not see either of these colours as they both overlap
what is a monochromat?
ind who is totally colour blind and can inly see the world in black white and grey tones
what is the range of nanometers(wavelengths) that we can perceive without sensitivity?
what is the nonometers for blue and red colours?
we can perceive colours between 380-760 nm
blue = short wavelengths and high freq (400nm)
red = long wavelengths and low freq (700nm)
what is radiance?
how much light and energy the light source is producing
what is illuminance?
how much light is hitting an object
- depends on the distance the light source is from the object
what is luminance?
how much light is leaving or coming off of the object
what is retinol luminance?
how much light from the object hits the retina
what is reflectance?
the ratio from the illuminance hitting the object to the the luminance coming off the object
what is a beat?
2 tones that are close in frequency
what is a beat?
2 tones that are close in frequency
what are the 2 things that need smell to be to enter the neurons?
has to be volatile = molecules from substance must evaporate to form vapor that can be inhaled
water soluable = be able to get through excess mucus to smell better and reach cilia
what is the system of smell?
-odour mol go up nasal to reach olf. epith.
- has to get through the mucus first to reach the ends of the cilia so the odour mol can latch on
- odour molecules fire and send signals to the olfactory tract so it can turn into electrical impulses to send signal of what smell there is to your brain
what is the quality of smell?
there are 6 primary odours(henning)
- fruity, flowery, foul, burnt, resinous, spicy (placed on prism across from their opposites
- can combine up to 4 smells
- all 6 molecules can fit into a cilia (usually has 6-8 in each branch)
