Predicting inner speech use in autism spectrum disorder: The roles of verbal ability and cognitive profile

Studies of inner speech use in ASD have produced

conflicting results. Lidstone et al., J Autism Dev

Disord (2009) hypothesised that Cognitive Profile (i.e.,

discrepancy between non-verbal and verbal abilities) is a

predictor of inner speech use amongst children with ASD.

They suggested other, contradictory results might be

explained in terms of the different composition of ASD

samples (in terms of Cognitive Profile) in each study. To

test this, we conducted a new analysis of Williams et al.’s,

J Child Psychol Psychiatry 48(1): 51–58 (2008) data on

inner speech use in ASD. This revealed verbal ability

predicted inner speech use on a short-term memory task

over and above Cognitive Profile, but not vice versa. This

suggests multiple factors determine whether children with

ASD employ verbal mediation.