Sensory motor inhibition as a prerequisite for theory-of-mind: A comparison of clinical and normal preschoolers differing in sensory motor abilities

After distinguishing between neocortical abilities for executive control and subcortical sensory motor skills for proprioceptive and vestibular integration, we compare a sample of 116 normal preschoolers with a sample of 31 preschoolers receiving occupational therapeutical treatment. This is done in an experimental design controlled for age (mean: 49 months), sex, SES, linguistic abilities, and intelligence. Inhibition and theory-of-mind are measured with test batteries. Results show that children having deficits in sensory motor inhibition are less competent in conflict inhibition and in theoryof-mind. Regression analyses reveal that in the clinical sample conflict inhibition is a significantly stronger predictor of theory-of-mind than in the control group. These results point at a basic sensory motor inhibitory ability as a prerequisite for the development of theory-of-mind.