Beliefs, attitudes, and old information about autism appear to need constant re-examination as new concepts, information, and treatment approaches continuously become available. In recent years professionals and parents have reflected about concepts such as inclusion and theory of mind and interventions ranging from holding therapy to manual signing. Movement differences has become a contemporary topic in the area of autism in the 1990's, although the neurobehavioral construct itself is referenced in pre-1990's medical chronicles. Present discussion of the topic with regard to individuals with autism represents a broadening of application and reflection beyond the original documented disability groups. The significant questions and possibilities presented by the topic of movement differences compel people with an interest in autism to engage in some personal re-assessment. This paper presents some basic information regarding the nature of movement differences and provides suggestions as to its functional application. Readers are urged to read full text discussions by Donnellan & Leary (1995), and Leary & Hill (1996), and to remember that movement difference is a construct and not a new disability category.
Recent widespread awareness of selected aspects of movement differences began with the publications and trainings of Rosemary Crossley (1980) and Doug Biklen (1990) on the technique of facilitated communication. The need for an assisted movement/emotional support technique (i.e., facilitated communication) arose from supposition. Later, direct confirmation occurred when selective nonverbal individuals indicated that they did indeed have difficulty initiating or sustaining independent coordinated motor movements. Controversy still surrounds the use of the facilitated communication technique in terms of consistent authentic authorship of messages. As part of the controversy, there has been speculation that many nonverbal individuals who were introduced to the facilitated technique may not have had a movement difference or a disturbance of the magnitude that prevented them from using more conventional and independently accessed augmentative means of communication (e.g., Liberator™, DynaVox®, non-commercial manual communication boards). There is no significant data to support or refute the prediction about prevalence. In comparison to dialogues and disagreements about facilitation as a technique, discussion about the more broadly defined construct of movement ability or difference has been less provocative. If anything, the new information has encouraged others to notice potential movement differences in individuals with autism that had been previously overlooked and to engage in pondering about new interpretations of human behavior.
The reframing of observations that derived from the facilitated communication movement, however, proved to be just the tip of the iceberg in the topic area of movement differences. Many neurologically based disorders such as Parkinson's and Tourette's appear to share symptoms that are also found in some individuals with autism. The neurobiological basis for autism per se, however, is not considered to be the causal agent for the movement difference symptoms that have been noted but there does seem to be some relationship. Selective examples of shared characteristics or symptoms include the following: repetitive movements, abnormal gait, abnormalities in muscle tone, lack of imitation, self injurious behavior, echolalia, and difficulty initiating, stopping or switching actions (Donnellan & Leary, 1995).
On a semantic basis one would guess that movement differences literally referred to observable motor movement patterns. Instead, movement differences, as described by Donnellan and Leary, and others, has a more figurative meaning. While the construct does include movement patterns or actions, it also encompasses posture, speech, perception, thought, attention, consciousness, motivation, memories, and emotion. Overlaid on each of these is the issue of volitional or voluntary control (Donnellan & Leary, 1995; Leary & Hill, 1996). The more figurative or metaphorical nature is evidenced by discussions of someone's internal mobility to cease thinking about a particular thought, to switch a perceptual focus, or to combine memories with new thoughts. Both Leary and Donnellan define movement differences through visual information displays and examples rather than through an exact dictionary-type of definition.
Recognizing Possible Instances of Movement Differences
Recognition of movement differences as a factor in observed behavior certainly will force rethinking in the area of behavioral analysis. It will no longer be possible to only hypothesize about the probable purpose or motivation for a given behavior. Since specific actions may not be under the individual's volitional control, there may be a mismatch between personal motivation and the action observable by others. There also may be a mismatch between a service provider's hypothesis about the intent or benefit of an action and the actual intent of the person with a movement difference. The mismatches can best be illustrated by some common examples. Movement differences may be a co- occurring factor or the sole factor behind the observed behavior in any of the illustrations and the hypothesized intent of the behaviors.