What does the place theory of pitch?
The place theory of pitch perception suggests that different portions of the basilar membrane are sensitive to sounds of different frequencies. More specifically, the base of the basilar membrane responds best to high frequencies and the tip of the basilar membrane responds best to low frequencies.
Who proposed the place theory of pitch perception?
Hermann Ludwig Ferdinand von Helmholtz
A theory of pitch perception first proposed in 1865 by the German physiologist, physicist, and mathematician Hermann Ludwig Ferdinand von Helmholtz (1821–94) according to which the perceived pitch of a tone depends on the position or place on the basilar membrane of the auditory receptors that transmit nerve impulses.
What is an example of place theory?
The place theory of hearing is used to explain how we distinguish high-pitched sounds that possess a frequency that exceeds 5,000 hertz. For example, a sound that measures 6,000 hertz would stimulate the spot along the basilar membrane that possesses a characteristic frequency of 6,000 hertz.
What is frequency theory of pitch?
a late 19th-century theory specifying that pitch is coded by the rate at which action potentials are generated by auditory neurons within the basilar membrane of the ear.
What is the problem with the place theory?
The biggest problem of the place theory is that it fails to identify the pitch of a stimulus with missing fundamental. According to Helmholtz’s theory, it is impossible to perceive a pitch when there is no spectral peak at the position along the basilar membrane which corresponds to the frequency of the pitch.
What is ITD and ILD?
The information embodied in interaural time differences (ITDs) and interaural level differences (ILDs) (a) allows listeners with normal hearing (NH) to locate sound sources on the horizontal plane, and (b) has a significant role in generating high levels of speech recognition in complex listening environments, for …
What is the difference between the temporal theory and the place theory of pitch?
Two rival theories have slugged it out over the years: ‘place theory’, in which pitch is determined by which neurons are active, and ‘temporal theory’, in which pitch is determined by how the neurons are active, specifically in terms of their temporal firing patterns.
How do we locate the source of sounds?
Humans use two important cues to help determine where a sound is coming from. These cues are: (1) which ear the sound hits first (known as interaural time differences), and (2) how loud the sound is when it reaches each ear (known as interaural intensity differences).
What is interaural attenuation?
the reduction in intensity, at one ear, of an acoustic stimulus presented to the other ear canal as the sound is transmitted through the head; for air conduction, the reduction approximates 35 dB, but for bone conduction, it is 10 dB or less.
What is interaural delay?
Interaural Time Delays For example, a sound on the right side will arrive at the right ear a short time before it arrives at the left ear, while a sound from directly ahead will arrive at the ears at the same time.
Where does ITD occur in the brain?
ITD sensitivity in the mammalian brain arises in the medial superior olive (MSO) in the auditory brainstem where cells are sensitive to microsecond differences in the arrival time of inputs from the two ears.
What is masking plateau?
In clinical masking, the plateau is a state in which the non-test ear (NTE) is completely masked by the noise and tone is heard only by the test ear (TE). At least 15 to 20 dB of plateau width is needed to obtain valid threshold.