Week 6 - Sensation & Perception 2 Flashcards
What is sound caused by?
Vibrations
Wave frequency =
Pitch
Wave amplitude =
Loudness
Wave complexity =
Timbre
The human ear is sensitive to mechanical vibration from what frequency (Hz)?
20-20,000Hz
Explain the Place Theory of pitch perception
Our perception of sound depends on where each component frequency produces vibrations along the basilar membrane.
For high pitch, hairs in specific areas of the basilar membrane activate specific regions in the primary auditory cortex
Explain the Frequency Theory of pitch perception
The frequency of the nerve impulses corresponds to the frequency of a tone, which allows us to detect its pitch.
For low pitch, the rate of action potentials signals frequency of sound wave (up to 100Hz)
Explain the Volley Theory of pitch perception
Groups of neurons of the auditory system respond to a sound by firing action potentials slightly out of phase with one another so that when combined, a greater frequency of sound can be encoded
Combinations of action potentials slightly de-synchronised collectively signal the frequency of sound wave/
What is Conductive hearing loss?
Problems in the outer/middle ear
What is Sensorineural hearing loss?
Problems in the inner ear, auditory nerve and auditory cortex
3 causes of hearing loss
genetic
disease/injury
age-related
What is the relationship between olfaction and gustation?
They work together to enhance liking or disliking some foods
Olfaction is what?
smell
Gustation is what?
taste
Olfaction is like the lock and key analogy, why?
Because olfactory receptors code for one odour
How many odours can humans identify?
2000-4000
What types/groups of people are considered to have better olfaction? (3)
young people
females
non-smokers
What are the 4 main gustations? and what is the extra 5th one that has recently been added?
Sweet Sour Bitter Salty Umami
Smell and taste converge on parts of what system?
limbic (orbitofrontal cortex, amygdala)
What is the Somatosensory System?
Specialised receptors within the skin detect physical stimuli from the external environment eg temp and pain
What are the 3 classes of skin receptors?
Pressure - “mechanoreceptors”
Temperature - “thermoreceptors”
Pain - “nociceptors”
What is the Phantom Limb illusion?
A vivid sensation that a missing limb is still present
How can Phantom Limb pain be relieved?
With a mirror box