Evaluating a Treatment Package for Chronic Hand Mouthing in a Child with Autism

Introduction

Hand mouthing is a common behavioral concern in individuals with autism spectrum disorder (ASD). This repetitive behavior can lead to physical harm, including tissue damage, infections, and interference with learning and social engagement. Traditional behavior management techniques, such as reinforcement-based strategies, may not always be effective, especially when the behavior is maintained by automatic reinforcement.

A recent study by Thakore, Kelly, Petursdottir, and Stockdale (2024) published in Behavior Analysis in Practice examines an intervention designed to reduce chronic, stereotypic hand mouthing in a 7-year-old child with autism. The study’s findings provide valuable insights into treatment approaches for behavior-resistant cases.

Understanding Hand Mouthing and Its Effects

Hand mouthing is a form of repetitive, self-injurious behavior in which an individual frequently places their hands in or near their mouth. It often serves as an automatically reinforced behavior, meaning the individual engages in it for self-stimulation rather than to obtain a social or tangible reward.

Risks Associated with Hand Mouthing

1. Physical Injury: Risk of infections, tissue damage, and calluses.
2. Skill Interference: Limits engagement in functional activities such as using utensils or engaging in fine motor tasks.
3. Increased Use of Restraints: If the behavior becomes severe, mechanical restraints like gloves or arm splints may be used, which can limit mobility and independence.

When conventional reinforcement strategies fail, behavior analysts must explore alternative intervention methods to reduce such behaviors effectively.

Overview of the Study

Participant and Setting

The study focused on a 7-year-old child named Bonnie who displayed persistent hand mouthing. Previous interventions, including reinforcement strategies and environmental modifications, had little to no effect on reducing the behavior. The treatment was conducted in a center-based autism program, allowing for controlled implementation and monitoring.

Initial Behavioral Assessments

Before designing an intervention, the researchers conducted a functional analysis (FA) to determine what was maintaining the behavior. The results indicated:

• The behavior was automatically reinforced, meaning it was self-stimulatory in nature.
• Attempts to use alternative reinforcement strategies (such as preferred items or social reinforcement) were ineffective.
• The behavior followed a repetitive sequence (e.g., chin touching before hand mouthing), which informed later treatment strategies.

The Treatment Intervention

Baseline Phase

During the baseline phase, Bonnie’s hand mouthing was observed without intervention. She consistently engaged in the behavior despite access to sensory items and reinforcement for alternative behaviors.

Initial Treatment Attempts

The team attempted a combination of traditional behavior management approaches, including:

1. Noncontingent Reinforcement (NCR): Providing constant access to alternative sensory stimuli to reduce the motivation for hand mouthing.
2. Differential Reinforcement of Alternative Behavior (DRA): Reinforcing alternative, appropriate behaviors while withholding reinforcement for hand mouthing.
3. Response Interruption and Redirection (RIRD): Physically or verbally redirecting Bonnie to an alternative activity whenever she engaged in hand mouthing.

Despite these strategies, Bonnie continued engaging in the behavior at high rates.

Modified Treatment Approach

Recognizing the need for a different approach, the researchers implemented a contingent protective equipment strategy alongside RIRD.

1. Use of Contingent Protective Equipment: Soft mittens were introduced to interrupt the behavior chain. Mittens were removed when Bonnie refrained from initiating hand mouthing.
2. Adjustments to RIRD: The team began interrupting at an earlier step in her behavior pattern (chin touching) rather than waiting for full hand mouthing to occur.
3. Intervention Fidelity: Throughout the study, observers ensured that treatment was implemented consistently and accurately.

Results and Key Findings

The combination of contingent protective equipment and modified RIRD led to a substantial reduction in Bonnie’s hand mouthing. Major findings included:

• Significant decrease in hand mouthing as compared to baseline and initial treatment attempts.
• Sustained reduction over time, indicating the strategy was effective beyond the initial implementation phase.
• Improved engagement in functional activities, as Bonnie spent less time engaged in self-injurious repetitive behaviors.

Social Validity and Quality of Life

Beyond reducing the behavior itself, treatment interventions should also improve an individual’s overall quality of life. This study’s findings suggest that the intervention:

1. Allowed More Independent Participation: With lower occurrence of hand mouthing, Bonnie could engage in more daily activities.
2. Decreased the Need for Constant Supervision: Caregivers and teachers could focus on facilitating skill acquisition rather than managing the behavior.
3. Offered Practical Treatment Modifications: The intervention proved feasible for use in a clinical setting without excessive reliance on restrictive strategies.

Implications for Clinical Practice

For behavior analysts working with clients who engage in automatically reinforced behaviors, this study highlights three key takeaways:

• Behavior sequences matter: Identifying the earliest point in a repetitive behavior chain allows for more effective intervention.
• Protective equipment should be used strategically: When reinforcement and redirection fail alone, contingent environmental modifications (such as mittens) may help disrupt entrenched behaviors.
• Treatment should focus on long-term skill development: Reducing problematic behavior is only part of the solution—promoting replacement behaviors and engagement in functional activities is equally important.

Final Thoughts

This study provides a compelling case for using contingent protective equipment alongside modified RIRD to treat persistent, treatment-resistant self-stimulatory behaviors in children with autism. By considering behavior chains, reinforcement contingencies, and protective strategies, behavior analysts can develop more effective interventions for their clients.

For those interested in reading the full study, you can find it here: https://doi.org/10.1007/s40617-024-00956-8.

By staying informed on emerging research, practitioners can continually refine their approaches to best support individuals with ASD.