Mirror-touch synaesthesia: the role of shared ... - UCL Discovery

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Colour Sensitivity: Total Error Score
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Chapter 3
Figure 3.1 Synaesthetes who experience colour outperformed individuals who do not
experience synaesthetic colour on a measure of colour perception (a). This pattern of
performance was shown by synaesthetes who experience colour only relative to nonsynaesthetic
controls and by synaesthetes who experience both colour and touch
relative to non-synaesthetic controls, but not by synaesthetes who experience touch
only relative to controls (b). Error scores are based on the deviation from the
expected ordering of hues. Superior colour performance is indicated by a lower error
score. * = p < .05.
Gratings Orientation Test
Figure 3.2 shows the average tactile discrimination thresholds for all subjects
on the gratings orientation test. Enhanced tactile discrimination is reflected in a lower
threshold value (in millimetres). Thresholds were calculated using the following
formula and provide an estimate of the grating level which would lead to a 75%
response level:
Group
g75 = glow + ((0.75 -plow)/(phigh - plow)) (ghigh - glow)
g = grating spacing
*
Touch-Synaesthetes
Dual-Synaesthetes
Colour-Synaesthetes
Non-synaesthetes