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

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CHAPTER 9: CONCLUSIONS
Chapter 9
In this chapter, the empirical findings from chapters 2-5 and 7-8 of this thesis are
discussed in a wider context. Chapters 2-5 addressed the prevalence, neurocognitive
mechanisms, and consequences of mirror-touch synaesthesia for perception and
social cognition. These findings are discussed in relation to previous research on
synaesthesia and future studies on the neurocognitive mechanisms of mirror-touch
synaesthesia are also described. Chapters 4 and 5 also used mirror-touch
synaesthesia to inform us about the role of sensorimotor resources in social
cognition. These findings were complemented by studies in chapters 7 and 8, which
investigated the impact of suppressing sensorimotor representations on the expression
recognition abilities of healthy adults. The findings from chapters 4, 5, 7 and 8 are
discussed in the context of research on social cognition and sensorimotor accounts of
social cognition.
9.1 Introduction
As noted in the introduction to this thesis, synaesthesia is a condition in which
one attribute of a stimulus (the inducer) triggers a conscious experience of another
attribute (the concurrent) not typically associated with the inducer. For example, in
grapheme-colour synaesthesia the letter ‘a’ may trigger synaesthetic experiences of
colours. A large body of synaesthesia research has focussed on grapheme-colour
synaesthesia, which is often reported as being one of the most common forms of the
condition (Baron-Cohen, Burt, Smith-Lailtan, Harrison, and Bolton, 1996; Rich,
Bradshaw, and Mattingley, 2005; Simner et al., 2006). More recently, a newly
documented form of synaesthesia has been described in which individuals experience
tactile sensations on their own body simply when observing touch to another’s body
(mirror-touch synaesthesia; Banissy and Ward, 2007; Blakemore, Bristow, Bird, Frith,
and Ward, 2005). The studies in the first five chapters of this thesis investigated the
neurocognitive and perceptual profiles of mirror-touch synaesthesia. In addition, the
role of sensorimotor simulation mechanisms in social cognition was examined by
using principles of neuropsychology (in the case of mirror-touch synaesthesia) and