Repetitive behaviors, such as a young child rubbing their feet together, often cause concern for parents who may search for connections to conditions like Autism Spectrum Disorder (ASD). This specific action is known as a motor stereotypy and is frequently observed in infants and toddlers. It is important to separate common, benign developmental habits from genuine developmental concerns. Understanding the context, frequency, and accompanying behaviors provides clarity on whether this movement is a normal self-soothing action or an indication of a broader issue. This article explains the context for feet rubbing and the actual indicators used by clinicians for an ASD diagnosis.
The Short Answer: Feet Rubbing and Autism
Feet rubbing, in isolation, is not a diagnostic indicator for Autism Spectrum Disorder (ASD). While repetitive movements are included in the diagnostic criteria for ASD, this specific behavior is common across all children and is rarely the sole reason for a developmental evaluation. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) lists “stereotyped or repetitive motor movements” as a potential symptom, but the presence of just one action is insufficient for a diagnosis.
This behavior is considered a simple motor stereotypy. It only becomes a potential concern when it is highly frequent, intense, and occurs alongside significant deficits in social communication and interaction. Clinicians rely on a comprehensive pattern of behaviors, not an isolated action, to identify a developmental difference. This movement is widely accepted as a form of self-soothing or self-stimulatory behavior, often called “stimming.”
Typical Reasons for Repetitive Motor Behaviors
Repetitive motor behaviors in infants and toddlers are a normal part of development. These movements, which include feet rubbing, body rocking, or leg kicking, serve important functions as self-regulatory behaviors that help the child process their environment and manage their internal state.
A primary reason for feet rubbing is sensory exploration and feedback. The repetitive friction provides tactile stimulation and pressure input, which can be calming or pleasurable to the nervous system. This action allows the child to discover their body parts and understand how they interact with the world. The rhythmic motion activates pressure receptors in the skin, often triggering a relaxation response, making it a common habit when resting or falling asleep.
Another function is self-soothing, particularly during periods of transition or overstimulation. When a child is tired, anxious, or overwhelmed, the rhythmic movement provides predictable, steady input that helps regulate their emotions and nervous system. These early repetitive movements are also a form of motor practice. For most children, these simple stereotypies naturally decrease in frequency as they develop more complex motor and self-regulation skills.
Core Indicators of Autism in Early Childhood
A diagnosis of Autism Spectrum Disorder requires evidence of persistent deficits across two core areas of functioning, extending far beyond an isolated repetitive movement like feet rubbing.
Social Communication and Interaction Deficits
The first area involves persistent deficits in social communication and interaction across multiple contexts. This includes a lack of social-emotional reciprocity, such as difficulty with back-and-forth conversation or reduced sharing of interests and emotions. Children may also show nonverbal communication differences, such as limited use of gestures, poor eye contact, or difficulty understanding body language. A lack of joint attention, where the child does not follow an adult’s gaze or point to share an object of interest, is a particularly telling early sign. These social differences represent pervasive challenges in connecting with others.
Restricted and Repetitive Behaviors (RBBs)
The second core area involves restricted, repetitive patterns of behavior, interests, or activities (RBBs). While simple motor stereotypies fall under this umbrella, the behaviors indicating ASD are typically more complex and pervasive. These include an insistence on sameness, such as extreme distress at minor changes in routine or rigid thinking patterns. Highly restricted, fixated interests that are abnormal in intensity or focus are also common. The RBBs also encompass sensory differences, such as hyper- or hypo-reactivity to sensory input, like indifference to pain, an adverse response to specific textures, or a visual fascination with spinning objects.
When to Consult a Pediatrician
While the isolated act of rubbing feet together is almost always benign, certain contexts warrant professional consultation regarding any repetitive behavior. A pediatrician should be consulted if the behavior is accompanied by significant developmental delays in other areas. This includes a noticeable delay in meeting language milestones, such as not using single words by 18 months or two-word phrases by two years of age.
Consultation is also suggested if the repetitive behavior is so intense or frequent that it interferes with the child’s ability to engage in daily activities, play, or learning. For example, if the foot rubbing prevents the child from exploring toys or participating in social interactions, it may be impeding development.
Parents should also seek an evaluation if they observe a regression of previously acquired skills. This involves a child losing words they once had or discontinuing social behaviors, such as waving or responding to their name. These combined factors, rather than the simple presence of foot rubbing, form the basis for a developmental screening and early intervention referral.