Superior estimation abilities in two autistic spectrum children

Abstract

Anecdotal reports of superior estimation abilities in autistic individuals (e.g., Sacks, 1985) have never been confirmed empirically. We present here case studies of 2 children with autistic spectrum diagnoses and report remarkable abilities in estimation for several quantifiable dimensions. K.T. and G.T. were tested at 9 years of age for estimation of rank, numerosity, time, weight, length, surface, distance, and precise enumeration for small numbers. Their performances were compared to those of 6 age- and IQ- matched comparison children. K.T. demonstrated a superior level of performance in estimating rank (e.g., which set has larger numerosity?) but his performance in other tasks was average. G.T. displayed outstanding performance in estimating numerosity, time, weight, surface, length, and distance, with average performance in other tasks. These results show that certain autistic spectrum individuals may develop superior and highly specialized abilities in estimation. We discuss these findings in relation to the role of "veridical mapping" in the development of special ability (Mottron, Dawson, & Soulieres, 2009; Mottron, Dawson, Soulieres, Hubert, & Burack, 2006a). Veridical mapping is the detection of isomorphism within a code, between two codes, or between one code and isomorphic elements of the world. Within this framework, it is proposed that estimation abilities, like absolute pitch, rely on the ability to map a verbal code with a specific magnitude of a psychophysical dimension.

Veridical mapping in the development of exceptional autistic abilities

“…AP is consistently observed among savant autistic musicians (e.g. Miller, 1999;Sloboda et al, 1985;Young and Nettelbeck, 1995) and frequently co-occurs with other types of savant abilities such as 3-D drawing, mental computation, and superior estimation abilities Heaton et al, 2008b;Mottron et al, 1999;Soulières et al, 2010). Conversely, autistic features are also observed in AP possessors, indicating a non-random link between the two conditions.…”

“…For example, his estimation of the elapsed time between 15 and 95 s displayed a deviation rate between 1.1% and 3.3%, around one-tenth the deviation rate of IQ-matched TD children. His parents reported that he spent hours estimating the surfaces of rectangles and circles, and determining time in relation to the size of projected shadows (Soulières et al, 2010). When questioned about the mechanisms he used to perform these calculations, G.T.…”

Diminished Whole-brain but Enhanced Peri-sylvian Connectivity in Absolute Pitch Musicians

“…Interestingly, there are several reports of superior pitch processing and AP abilities in ASD patients. (Soulieres et al, 2010;Brenton, Devries, Barton, Minnich, & Sokol, 2008;Heaton, Davis, & Happe, 2008;Bonnel et al, 2003;Brown et al, 2003;Heaton, 2003).…”

Designing a “better” brain: insights from experts and savants

“…We know that individuals with autism are less susceptible to some illusions (Walter et al, 2009; Mitchell et al, 2010), and that they process information in a less holistic way (Nakahachi et al, 2008), for example paying more attention to details, which can result in savant skills such as extreme memory for detail and speed in counting objects (numerosity) (Soulieres et al, 2010). We also know that some savant skills can be artificially induced in normal individuals, for example by low-frequency repetitive transcranial magnetic stimulation (Snyder et al, 2006; Boggio et al, 2009; Snyder, 2009) or transcranial direct current stimulation (Chi and Snyder, 2012).…”