Pattern detection in autism research

Monday, 21 May, 2012

People with autism face numerous challenges in daily life. For example, a child with autism may experience difficulties in social interactions and playtime activities or some difficulty in verbal and non-verbal communication. In some cases, self-injurious behavior is one of the challenges a person with autism and his or her care-givers and parents face. It is a really disturbing behavior which can have serious consequences. There is a lot of information on the internet about how to cope with self-injurious behavior, but still there is a lot unknown. Researchers are searching for indicative behaviors, treatments, and other factors that help people, parents, and society deal with this dangerous behavior. In this blog, a study is presented which adds to our understanding of how to do behavioral research. It’s about a method which goes beyond trigger response behavior analysis and which stretches research boundaries.

T-pattern analysis

New insights into self-injury behavior are presented by Sandman et al. 2012. T-pattern analysis allowed them to reveal temporal patterns associated with self-injurious events. They used a method for detecting non-linear, real-time patterns: T-pattern analysis with Theme™.

  • Theme is a software package for pattern detection in sequential data and was originally developed for the analysis of social interactions. Its algorithms are based on relationships in the order and timing of behaviors. These relationships are critical in any goal directed action. Thus the time structures detected by Theme often reflect the purpose of behavior. Instead of the traditional strategy to examine how events influence target behavior, their findings suggest that the focus should be to examine how a target behavior influences the emergence of more global patterns of events and behaviors over longer periods of time (Magnusson, 2000).


Self-injury behavior

Self-injurious behaviors are associated with numerous manifestations, including autism (Sandman 2009a). Sandman et al. (2012) explain that there are two dominant views about the mechanisms motivating self-injury behavior (from cutting, hitting, or biting themselves to banging their head against solid objects resulting in broken bones). The first is the behavioral view in which it is stated that self-injury behavior is a response to environmental or social stressors. The second view indicates that self-injury behavior is mostly motivated by an underlying biological disturbance either in pain and pleasure system or in the dissipation or generation of arousal. The purpose of Sandman’s study was to determine if self-injury behavior was nested in complex behavioral networks and to determine the influence of its occurrence on the organization of behavioral-environmental interactions.

Observe behavior throughout the day

Thirty-two participants were observed by research staff during a ‘normal’ day and behavioral and environmental events were recorded using a handheld computer assisted observational system (The Observer®). The influence of self-injury behavior on patterns in behavior was compared with behavior patterns during sessions without self-injury behavior.

Unique patterns

With this approach, Sandman et al. discovered that there are non-linear networks emerging during sessions where self-injury behaviors occurred. The patterns became more in number and more complex compared to a session without self-injury behavior. So it became more likely to observe a pattern during a session with self-injury. However, these environmental-behavioral patterns weren’t repeated within and between participants, they were unique from participant to participant and from session to session.

New approach to studying self-injury behavior

The authors put forward that self-injury behavior may serve a general structuring function on behavioral patterns, rather than influencing the contents of any particular type of pattern. Therefore, not the events that influence self-injury behavior, but the global patterns of events and behavior over longer periods of time should be studied, using more advanced tools such as Theme to analyze the behaviors over time. Sandman et al. explain that their results suggest that it is not just a behavior in response to avoidance or escape. Self-injury behavior contributes to complex organized behavioral-environmental patterns.

  • Sandman, S.A.; Kemp, A.S.; Mabini, C.; Pincus, D.; Magnusson, M. (2012). The role of self-injury in the organization of behaviour. Journal of Intellectual Disability Research56 (5), 516-526.
  • Magnusson M. S. (2000) Discovering hidden time patterns in behaviour: t-patterns and their detection. Behavior Research Methods, Instruments,& Computers32, 93–110.