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

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Chapter 4
is a growing body of evidence suggesting that individuals with autistic spectrum
disorder (ASD) have impaired activity in the action mirror system (Dapretto, Davies,
Pfeifer, Scott, Sigman, Bookheimer, and Iacoboni, 2006; Oberman, Hubbard,
McCleery, Altschuler, Ramachandran, and Pineda, 2005), which may lead to the
deficits in imitation and empathy observed in ASD (Iacoboni and Dapretto, 2006;
Oberman and Ramachandran, 2007; but see Southgate and Hamilton, 2008).
As discussed in preceding chapters, previous functional magnetic resonance
imaging findings indicate that synaesthetic tactile experiences in mirror-touch
synaesthesia are associated with hyperactivity in the same mirror-touch network that
is evoked by observed touch in non-synaesthete controls in which no overt tactile
experience is elicited (Blakemore et al., 2005). As such, mirror-touch synaesthesia
may offer a unique opportunity to explore the role that the tactile mirror system has in
empathy because it enables investigations into the relationship between heightened
sensorimotor simulation in the mirror-touch system and empathic sensitivity.
To address this possibility two experiments were conducted. In experiment 1,
the empathic abilities of ten mirror-touch synaesthetes were compared to a
synaesthetic and non-synaesthetic control group. In experiment 2, potential factors
which may contribute to heightened empathy were investigated by contrasting mirror-
touch synaesthetes with non-synaesthetic participants on empathy and personality
measures.
4.2 Experiment 1: Mirror-touch synaesthesia and empathy
Participants
Ten mirror-touch synaesthetes (6 females and 4 males, mean age ± Std. Error
= 37.6 ± 5.59 years) and twenty non-synaesthetic controls matched for age and gender
(12 females and 8 males, mean age ± Std. Error = 32.95 ± 3.24 years) took part in the