Understanding perceptual judgment in autism spectrum disorder using the drift diffusion model.

Abstract

Objective: Two-alternative forced-choice tasks are widely used to gain insight into specific areas of enhancement or impairment in individuals with autism spectrum disorder (ASD).Data arising from these tasks have been used to support myriad theories regarding the integrity, or otherwise, of particular brain areas or cognitive processes in ASD. The drift diffusion model (DDM) provides an account of the underlying processes which give rise to accuracy and reaction time distributions, and parameterises these processes in terms which have direct psychological interpretation. Importantly, the DDM provides further insight into the origin of potential group differences in task performance. Here, for the first time, we used the DDM to investigate perceptual decision making in ASD.Method: Adults with (N = 25) and without ASD (N = 32) performed an orientation discrimination task. A drift diffusion model was applied to the full RT distributions. Results:Participants with ASD responded more slowly than controls, the groups did not differ in accuracy. Modelled parameters indicated that: (i) participants with ASD were more cautious than controls (wider boundary separation); (ii) non-decision time was increased in ASD; and (iii) the quality of evidence extracted from the stimulus (drift rate) did not vary between groups.Conclusions: Taking the behavioural data in isolation would suggest reduced perceptual sensitivity in ASD. However, DDM results indicated that despite response slowing, there was no evidence of differential perceptual sensitivity between participants with and without ASD.Future use of the DDM in investigations of perception and cognition in ASD is highly recommended.

Autistic Traits in the Neurotypical Population do not Predict Increased Response Conservativeness in Perceptual Decision Making

“…The orientation discrimination was similar to that performed in Pirrone et al (2017) and Pirrone et al (under review). The task consisted of a sine wave grating stimulus with a spatial frequency of 4 cycles per degree, windowed by a Gaussian spatial envelope to have a diameter of 10 degrees.…”

“…We used three classical perceptual 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 F o r P e e r R e v i e w 5 tasks: an orientation discrimination task similar to the one used in the studies cited above; a motion discrimination task; and an attention7cuing task. The choice of the orientation task is motivated by the fact that this experimental paradigm was adopted by Pirrone et al (2017) and Pirrone et al (under review) for our previous investigations of decision making in autistic adults and children.…”

“…One difference with the studies of Pirrone et al (2017) and Pirrone et al (under review) is that here, for the orientation and motion experiment we also added speed and accuracy instructions, meaning that participants were instructed either to be fast or to be accurate, depending on the specific experimental block. This manipulation allowed us to test whether any potential differences in response criterion between low and high AQ scorers are consistent across speed and accuracy instructions, or whether potential differences in response criterion are specific only for one type of instruction, or whether the ability to flexibly adjust response criterion between the two instructions correlate with AQ scores.…”

Error monitoring in decision‐making and timing is disrupted in autism spectrum disorder

“…Based on previous findings [e.g., De Jonge et al, , Wallace & Happe, but see Pirrone et al, ], we did not expect significant differences between the perceptual decision‐making and timing performances of ASD and TD participants. In line with the ERN findings suggesting differences in error‐related processing and impaired metamemory and math error awareness in individuals with ASD [Cooper et al, ; Grainger et al, ; Grainger et al, ; Sokhadze et al, ], we expected disrupted error‐monitoring in children with ASD in the decision‐making and timing tasks.…”

Oscillatory entrainment mechanisms and anticipatory predictive processes in Autism Spectrum Disorder (ASD)

“…While not a specific focus of the current study, it is notable that the ASD group was significantly slower overall in both cued and uncued conditions. It bears emphasizing that this was not a modest difference but was found to be over 100ms, and that RT slowing in cognitive tasks is common in ASD across a range of tasks (Brandwein et al, 2013;Van der Hallen et al, 2015;Pirrone et al, 2017;Pirrone et al, 2020), and, among other changes in neuromotor functions, might represent motor control deficits in individuals with ASD (Morrison et al, 2018).…”