Perception: Synaesthesia Flashcards
What evidence is there suggesting the physical world is not the same as the perceived world?
- perception illusion = visual, auditory illusion
- Rubrics cube = showing a shadow even tho there isnt one :O
What is multi-sensory perception?
Process by which information from difference sense is brought together
What are the advantages of Mulit-sensory perception?
- more efficient + accurate vs processing each sense separately
- enables us to establish a single coherent perspective of the world
What are some examples of multi-sensory perception - gone wrong?
- Colour influence taste
- red wine = fruity - Sounds influence hardness
- crunchy sound = more hard - Vision influences sound
- let me put my glasses on
- McGurk Illusion
What is the McGurk illusion?
“ba” = ears
“Ga” = eyes
= “da”
- superimposition of the 2 sounds
When there is ambiguity between what the eyes and ears hear, what does the brain do?
- fuck it up
- but in a sophisticated way
What did Calvert et al in 1997 find suggesting a link between vision and auditory mulitsensory perception?
- fMRI
- showed silently looking at moving lips activated the auditory part of the brain
What is synaesthesia?
- concrete perceptual xp
= not imagined/ memory association - Elicited by stimuli in the external environment or by internal thoughts
= not hallucinations which occur spontaneously - automatic and cannot be suppressed
= unlike thinking/ imagining
What are 3 explanations for what potentially causes synaesthesia?
- Developmental synaesthisia
- Increased interactivity of the different brain regions
- Acquired synesthesia
What did Baron-Cohen et al in 1996 find about developmental synaesthesia?
- runs in families
- has a genetic component
- equally common in m + f
- present throughout the lifespan
- often triggered bu linguistic stimuli (letters, numbers, words etc)
What did they find similar across people with synesthesia?
- a natural propensity for hyper connectivity
- eg colour + letter perceptions
What did Hanggi et al in 2011 find challenging the idea of synesthesia being caused due to hyper connectivity?
- there seems to be greater connectivity in most regions of the brain vs just the synesthesia areas
In what ways can synesthesia be acquired?
- sensory deprivation
- pharmacologically triggered
- effects are temporary
What are the different ways in which science can prove synesthesia is real?
- look for high internal consistency
- Functional imaging studies
- Synesthesia stroop task
How can looking for high internal consistency prove synesthesia exist?
- “what colour is c”
- should be consistent over time is synesthesic
What did Nunn et al in 2002 find supporting the use of fundtional imaging to study synesthesia?
- structural connectivity
- eyes closed,
- listen to spoken words
Syn = coloured ares more lit up vs control - even if control trained or imagining colour
What is typically found when people with synesthesia are asked to do the stroop task?
- syn = colour do not override the actual colour BUT slows down their response since their is conflict in their head about what they see
= measure reaction time
= supports its automatic
Why should we care about synesthesia?
- can help relate to ‘normal’ cognition
- link between vision + touch
- number-space synaesthesia
What did Blakemore et al find in 2005 supporting the link between vision and touch?
- watching somebody else being touched activated our own somatosensory cortex
- but not when object being touched
- score higher on empathy
Explain the number-space synesthesia
- numbers are in spatial arrays
- Small no = LEFT
- Big no = RIGHT
What did Dehaene et al in 1993 find supporting the existence of number-space synesthesia?
- all seem to be faster at responding to small numbers w/ left etc
