## 3 Theorical Study: SMMs of Autistic Children  
People with ASD display nonfunctional, restricted, repetitive, and stereotyped patterns of activity known as Stereotypical Motor Movements (SMMs) [4]. SMMs have an impact on autistic children's functioning, inhibit skill development, and provide challenges to social integration in school and community settings [22]. The severity of ASD determines the intensity and frequency of SMMs, which might lead to self-injury in certain situations. Furthermore, they are not constant across time in the same person [4]. Table 1 categorizes several types of stereotypic behaviors based on their origins [23]. According to [9; 22], SMMs have a role in ASD diagnosis in addition to speech and socialization examination. The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) covers the following characteristics for diagnosing SMMs: (1) severity level (mild, moderate, or severe), and (2) association with another medical condition [9]. Mild SMMs can be readily repressed by distraction or sensory stimulation, but moderate behaviors need special precautions and behavioral changes because of their frequency. Both mild and moderate activities do not cause self-harm. Severe autistic behaviors, on the other hand, need continuous monitoring and prophylactic actions to avert significant harm [9]. Children with severe autism are sensitive to a wide range of internal and external stimuli and situations, such as stress, loud environments, sensory isolation, and other people's behavior [5]. Individuals thus have a number of acute SMMs, which can develop into Meltdown Crises, in which they become drowsy or lose control of their actions until an outside behavioral intervention is given [8]. The aggressive and furious behaviors of the autistic child experiencing the Meltdown crisis include hitting themselves, punching others, bashing their hands against the floor, placing themselves on the floor, rolling quickly, and more as seen in Table 1. \begin{table}
\begin{tabular}{c c c} \hline \hline
**SMM** & **Description** & **Sample from Public** \\ \hline
**Face** & \
\begin{tabular}{c} Grimacing, lips or tongue movements, opening the \\ mouth, mouth stretching, sucking objects \\ \end{tabular} &
\begin{tabular}{c} \\ \\ \end{tabular} \\ \hline
**Head and neck** & Head tilting, shaking, nodding, hair twirling, \\ headbanging, neck stretching & \\ \hline
**Trunk** & Body rocking, spin, spinning or rotation of the \\ entire body & \\ \hline
**Arm OR leg** & \
\begin{tabular}{c} Arms flapping, bilateral repetitive movements \\ involving the arms and hands such as crossing the \\ arms on the chest, and tapping one’s feet \\ \end{tabular} &
\begin{tabular}{c} \\ \\ \end{tabular} \\ \hline
**Arm OR leg** & \
\begin{tabular}{c} Arms flapping, bilateral repetitive movements \\ involving the arms and hands such as crossing the \\ arms on the chest, and tapping one’s feet \\ \end{tabular} &
\begin{tabular}{c} \\ \\ \end{tabular} \\ \hline
**T  
\end{table} 
Table 1: SMMs: descriptions and samples from public images. In clinical practice, several approaches for evaluating SMMs in ASD are employed, including caregiver interviews, caregiver surveys, and observational methods. (1) The Child Autism Rating Scale (CARS) [5] is a paper-and-pencil rating scale designed to differentiate autistic children's behaviors based on their severity and frequency from other problems based on general impressions and non-specific observations. (2) The Repetitive Behavior Scale-Revised (RBS-R) [24] is a questionnaire created for child caregivers to score child behavior based on a restricted number of pre-defined categories such as body rocking, hand flapping, and so on. (3) Video-based techniques [25] include analyzing the child's activities by watching video recordings of the encounter and manually offline coding them by an expert. Despite its dependability, this procedure is laborious and time-consuming; hence, it is not generally utilized.