Synesthesia Flashcards
(29 cards)
Topographical representations
brain mapping
synesthesia
joining of the senses
when one sensory stimulus evokes two or more specific, consistence, involuntary concurrent perceptual experiences
e.g number 4 brings to mind the feeling of blue, shapes elicit textures
motor homunculus
The motor homunculus is a visual representation of the body parts mapped onto the motor cortex in the brain
primary motor cortex
- size of each body part in this map reflects how much motor control and precision that part needs
e.g hands are large and legs are small (not needed in as precise movements)
sensory homunculus
body’s skin surface are mapped onto the primary somatosensory cortex in the brain.
size of body part on map represents how sensitive that part is e.g libs and finger tips are large, thigh is small
visual cortex retinotopic map
organised based on location of sensory field on retina, map onto visual cortex
neurons with receptor fields closer together on retina have cell bodies closer together in the cortex
Grapheme–color synesthesia
people automatically and consistently see colors when they view letters or numbers
common synesthesia types
one directional relationship
grapheme to colour
tone to colour
taste to touch
visual motion to sound
lexical to gusatory (goes both ways)
first test of synesthsia found generalised finding of…
links established with creativity and cognitive ability - caused lots of artists presenting with synesthsia
trigger stimulus
inducer
something that elicits something else
e.g SOUND elicits taste
response stimulus
concurrent
- the response to the inducer
e.g sound elects TASTE
how many people have it
0.1% - 4% of the population
more women than men
left handed people are more likely to have it
adventitious synesthsia
acquired synesthsia - e.g through medication, sensory deprivation, brain injury
induced synesthsia
synesthesia-like experiences that are intentionally brought about — usually through training, hypnosis, or psychoactive drugs.
does synesthesia saty consistent throughout life
yes it is consistent
e.g 7 is red
(will always be red)
pairings are concurrent - waht does this mean
person experiences both elements e.g shape triggers sounds both are perceived
how could have early childhood expericnes lead to synesthesia
- fridge magnets
- subject colours in primary school
associative vs projective synesthesia
Associative
- feel it in their mind
- e.g graphene colour synesthesia 7 = red
projective synesthesia (less common)
- concurrent in external space
- felt like they were looking at it
e.g writing a 7 in pencil, but see it as red
Nikola Tesla
tesla was known for his imagery - he never drew plans for his inventions, he just visualised then built them
he also struggled with people saying words and he ould visualise htat thing - would struggle to figure out if it was present itself, cause it was so vivid in his mind - he had to reach out to see it
bouba and kiki example
Rounded object bouba
Spikey one is kiki
this is because of the harsh point and sounds kiki
rounded and smooth and curved words is bouba
synesthesia with brain imaging
two different brain areas are active
- blindfolded synesthestic people and presented with spoken words - activaton of speech areas and visual cortrext (not seen in controls)
- another example present grapheme get activity in v4 (colour) and v8 (grapheme perception)
proving that synesthesia is not from experience
a congenitally colour blind person having grapheme colour synesthiesisa
and a different colour blin person having music colour synesthesia
ERP in sysnesthiec people
ERP seen in v4 100-150ms after seing a grpaheme or hearing sound
stroop test
faster on congruent (word matched colour), slower on incongruent (saying the ink colour not the word)
stroop test with synesthesia
say ink colour of numbers - easier for use byt people with synesthesia might have difficuwlty as they might be seeing two colours (one that it is represetned in their head vs what is on the pape)
