Recent research has shown reliability in robotic therapies for improvement in core impairments of autism. To improve the efficiency of communication using robots, this study evaluates the effectiveness of three different stimuli in a robotic intervention for children with autism spectrum disorder. Three different reinforcement stimuli presented in least-to-most (LTM) order introduced in this therapy using NAO robot are: visual (color variation), auditory and motion cues. The therapy was tested on 12 ASD children, 4 out of 12 children fall under mild category whereas 8 fall under the minimal category of autism. The experimentation was conducted for 2 months. Total 8 experiments were conducted with 1 trial per week. Total 12 cues were given per trial, 4 cues corresponding to each category. In total 96 cues were given per subject, 32 cues from each category. The results indicate a general trend for linking a particular autism category with the most effective stimulus for that category. It can be concluded that visual cue (color variation) is the most effective reinforcement stimulus for children with minimal autism as 8 out of 8 i.e., 100% were more responsive to visual cues whereas for children with mild autism category, 3 out of 4 i.e., 75% are more receptive towards the motion stimulus. The parameters used for assessment were joint attention and the time eye contact is maintained. Single factor ANOVA was used for the statistical analysis of results with alpha is 0.05 and p-value 0.0342, F value is 3.7456 and F critical value is 3.2834. The test was performed on 96 (8x12) trails in total, therefore ensuring the significance and reliability of our results.

This research article presents a preliminary longitudinal study to check the improvement in multi-human communication of children with Autism Spectrum Disorder (ASD) using a standardized multi-robot therapy. The research is based on a 3 step framework: 1) Human-Human Interaction, Stage-1 (HHI-S1), 2) Human-Robot Interaction, Stage-2 (HRI-S2), and 3) Human-Human Interaction, Stage-3 (HHI-S3). All three stages of the therapy consist of two command sets: 1) Controls commands and 2) Evaluation commands (auditory commands, visual commands, and combination of both). The concept of multiple robots is introduced to help multi-human communication and discourage isolation in ASD children. The joint attention of an ASD child is improved by the robotic therapy in stage 2 considering it as a key parameter for a multi-human communication scenario. The improvement in joint attention results in better command following in a triad multi-human communication scenario in stage 3 as compared to stage 1. The proposed intervention has been tested on 8 ASD subjects with 10 sessions over a period of two and a half months (10 weeks). Each session of human-human interaction (stage 1 and 3) consisted of 14 cues whereas 18 cues were presented by each robot for human-robot interaction (stage 2). The results indicate an overall 86% improvement in the social communication skills of ASD children in case of a multi-human scenario. Validation of results and effectiveness of the therapy has been further accomplished through the use of the Childhood Autism Rating Scale (CARS) score.

Autism spectrum disorder (ASD) affects a variety of social skills in children. One of the most important social skills that are affected by ASD is the ability to pay attention; ASD introduces unnecessary temporal delays in the attentional behavior of children toward external stimuli. This research focuses on identifying the effect of different social stimuli from robotic agents to assess the attentional behavior of children with ASD. Latencies in shifting attention and the number of attentions paid to a stimulus are defined as indexes of attentional behaviors for children with ASD. Nine children with ASD (seven males and two females, mean: 7.57 ± 2.57 years) that had minimal to no symptoms of autism participated in this study. Two robotic agents presented visual, speech, and motion social stimuli to the participants. Regarding social stimuli, a significant effect on the latency in shifting attention ( $\chi ^{2}(2)=9.55$ , $\text {p} = 0.008$ ) and the number of attentions paid ( $\chi ^{2}(2)=9.56$ , p = 0.008) was observed in children with ASD. The speech stimulus captured the children’s attention faster than the visual and motion stimuli in terms of latency in shifting attention and the number of attentions paid. Moreover, significant positive correlations were found for some pairs of stimuli among visual, speech, and motion stimuli for latencies in shifting attention, as well as the number of attentions paid using Pearson’s correlation analysis. This study contributes to the literature in terms of the impact of robotic stimuli on the attentional behavior of children with ASD.