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

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Chapter 4
study. All cases of mirror-touch synaesthesia were confirmed on the visual-tactile
spatial congruity paradigm described previously (Banissy and Ward, 2007; also see
Chapter 1 and Chapter 2 of this thesis for a description of the task).
In addition to this, twenty-five synaesthetes (22 females and 3 males, mean
age ± Std. Error = 43.96 ± 3.38 years) experiencing other forms of synaesthesia
(minimally grapheme-colour synaesthesia) but not mirror-touch synaesthesia took
part. These synaesthetes acted as a synaesthetic control group and demonstrated test-
retest consistency of ≥ 85% for letters, numbers and other verbal stimuli. The
synaesthete control group were included to ensure that any differences in empathy
were not due to a general feature of synaesthesia.
Materials and Procedure
All participants completed the Empathy Quotient (Baron-Cohen, Richler,
Bisarya, Gurunathan, and Wheelwright, 2003; Baron-Cohen and Wheelwright, 2004).
The EQ is a self report scale designed to empirically measure empathy. As noted
previously, empathy is a higher order construct and has been theorised as having two
main strands: (i) cognitive empathy – predicting and understanding another’s mental
state by using cognitive processes (i.e. role / perspective taking), and (ii) affective
empathy – experiencing an appropriate emotional response as a consequence of
another’s state (Baron-Cohen and Wheelwright, 2004; Preston and de Waal, 2002).
The EQ was developed to measure both cognitive and affective components of
empathy, has been validated on both clinical and control groups (Baron-Cohen et al.,
2003), and it has been shown to distinguish between these groups (Baron-Cohen et al.,
2003; Baron-Cohen and Wheelwright, 2004). In addition to this, the EQ has been
validated on measures of concurrent validity (Lawrence, Shaw, Baker, Baron-Cohen,
and David, 2004) and has been shown to have high test-retest reliability over 12