Lecture 11 Flashcards
gustation
taste
olfaction
smell
chemosenses
senses that detect chemicals
smell and taste
uses of taste and smell
prevent ingestion of toxins, avoid danger
social effects of smell- pheremones
core tastes
sweet, sour, salty, umami, bitter
what receptors does each taste bud cell contain?
receptors for each of the 5 core tastes
what causes a sweet taste?
sugars and artificial sweeteners
- fructose, glucose
- aspartame, saccharin
what causes a sour taste?
all acids
what causes a bitter taste?
no unique chemical class
-quinine, caffeine, peptide, phenols
what causes a salty taste
salts like table salt (NaCl) or NH4Cl, KCl
what causes an umami taste?
mono sodium glutamate, inosine 5’ - monophosphate, guanosine 5’ monophosphate
what are ‘super tasters’?
people with more papillae and taste buds
can detect ‘tasteless’ substance PROP
what is the suggested sixth taste?
starch
why may starch detection be important?
for detection as a slow release form of energy
how many types of molecule can smell differentiate between?
10,000 types
what is smell limited by?
our memory for what they indicate
classification for smells?
no satisfactory classification of odours
two routes for smell
orthonasal and retronasal
orthonasal
via inhalation
retronasal
during chewing/ swallowing
how many different types of olfactory receptor?
350
how many different types of olfactory receptor?
350
what do receptors of similar types project to
the same ganglion
how many chemicals can we discriminate (smell)
1 trillion
effect of attention on smell
sniffing
automatic attention
effect of labelling on smell
same odour will smell worse if labelled as a body odour rather than cheese
effects of learning
expert wine tasters identifying wone odours
top down effects on smell
attention, effect of labelling, effect of learning
the proust effect
vivid memories bought back by particular smells
close linkage between smell and what part of the brain (related to memory)
limbic system (emotion)
what is flavour a combination of? what else influences it?
gustation and olfaction
Texture, pain, sound, vision
how is the tongue represented in the somatosensory system
well represented
what does chilli act on:
pain receptors on teh tongue
what tastes can partially supress chilli?
best: sweet and sour liquids
salty intermediate
bitter not effective
when do foods taste crunchier and fresher?
when the sound is amplified of the high frequencies increased
when is food rated less sweet and salty?
in the presence of background noise
how does art inspired dishes impact tastiness ratings
increased ratings
what is multisensory perception
generated several independent energies, which are simultaneously detectable by different types of sensory detector
what do multisensory receptive fields refer to?
a single neuron that responds to more than one modality
what does the orbitofrontal cortex respond to?
taste and smell
what does the posterior parietal cortex respond to?
touch, vision and audition
what does multisensory integration do/ allow?
1) allows the detection of weak stimulus in another modality
2) can make sense of an ambiguous modality in another modality
3) can alter the quality of a stimulus in another modality
why is ventriloquism important?
an example of how visual information can influence where in space we perceive a sound source (multisensory integration)
what is the McGurk effect? what does it demonstrate?
if you watch lips moving make a gaga sound and hear baba, perceive baba
visual information is affecting the sound that you hear
rubber hand illusion
tactile input and visual input differ
a persons own hand may feel as if its in the location of a rubber hand
kinaesthesia- illusion of speed and explanation
70mph initially feels faster than 10 minutes later
Nervous system turns down the ‘gain’ on steady-state inputs
what is the effect of painted/ raised lines on a road?
increased awareness of speed via vision and audition
multisensory approach
what is synaesthesia?
stimulation of a particular type which always leads to another perceptual experience
how many people have synaesthesia?
1 in 200
what can training to experience genuine synaesthesia lead to?
an increase in IQ
