Figure 4.2 The staging of autistic deWcitsplay are among those eVects. The nativist theory-theory is that mind-
reading capacitygrows out ofthese earlier capacities, or at least that its
growth presupposes them. Baron-Cohen (1995) has suggested that this
process of maturation towards the mature theory involves three precursor
modules, an Intention Detector (ID), an Eye Direction Detector (EDD),
and a Shared Attention Mechanism (SAM). (It may be that ID is the
realiser of Wellman’s simple-desire-psychology, and that SAM is the
realiser of desire–perception psychology.) There is also some evidence of a
dedicated neurological system for the mind-reading module, involving a
circuit of interconnecting neural pathways (Baron-Cohen and Ring,
1994a: the circuit links the orbito-frontal cortex with the superior tem-
poral sulcus and the amygdala).
The so-called ‘executive function’ deWcits listed in the table above are
experimentally tested on such tasks as the Towers of Hanoi. This involves
transferring a set of discs of various sizes from one of three pegs to another,
one disc at a time, without ever having a larger disc sitting on top of a
smaller disc. Solving the task involves thinking about the positions of the
discs a few moves ahead. Autistic subjects are much worse at this task than
normal children, regularly repeating the same fruitless moves over and
over again (OzonoVet al., 1991; Harris, 1993). This is taken to indicate a
problem with the planning of actions which derives from diYculties with
hypothetical and/or counterfactual reasoning – reasoning about what will
Developmental studies 97