Lecture 17 Hearing Flashcards
Animals with ___________ eyes that have fields which significantly overlap afford good stereoscopic depth perception.
frontal
Animals with __________ eyes have poor stereoscopic depth perception (but gain a more panoramic view).
lateral
In the familiarization period, how do infants perceive a larger version of the same toy they had previously seen?
they perceive the larger object as being closer because they relied on familiar size to judge distance
infants develop the ability to use shadows to guide depth perception at approximately ________ months.
7
What is the physical definition for sound?
pressure changes in the air or other medium
What is the perceptual definition for sound?
the experience we have when we hear
Describe the 2 processes that allow loud speakers to produce sound.
- CONDENSATION (compression): diaphragm of speaker moves OUT, PUSHING air molecules together
- RAREFACTION (expansion): diaphragm of speaker moves IN, PULLING the air molecules apart
- the cycle of this process creates alternating high and low-pressure regions that travel through the air
What are pure tones?
tones which create changes in air pressure that can be described by a single sine wave
What is the basic building block of sounds?
pure tones
What is frequency?
number of cycles within a given time period
What is one Hz in terms of cycles and seconds?
one cycle/second
What is perception of pitch related to in terms of physical aspects of sounds?
frequency
What is tone height?
increase in pitch that happens when frequency increased
What is amplitude?
difference in pressure between high and low peaks of wave
What is perception of amplitude known as?
loudness
Which scale is used as a measure of loudness?
decibel (dB) scale
The decibel scale relates the ________ of the stimulus with the psychological experience of _______________.
amplitude; loudness
Both pure and complex tones are __________ tones.
periodic
What are periodic tones?
tones in which the waveform repeats
What are periodic complex tones?
consist of a number of pure tones called harmonics
What is the fundamental frequency? what is another name for it?
the repetition rate; aka first harmonic
What are higher harmonics?
multiples of the fundamental frequency
What are frequency spectras?
plot of the harmonics of a complex sound
What is the frequency of the first harmonic?
200 Hz
What is the frequency of the second harmonic?
400 Hz
What is the frequency of the third harmonic?
600 Hz