Psychiatric Times June 1997 p.55
New Diagnostic Tool Measures Infant, Infant-Toddler Information Processing Philip Zelazo, Ph.D., remembers the year that saw a resurgence in the interest and popularity of infancy and infant development. It was 1958, when works by Daniel Berlyne of the University of Toronto and Robert Fantz of Case Western Reserve appeared on the scene and helped ignite that curiosity. "From that period on." Zelazo said, "people realized the potential for getting at processing visual and auditory information in young babies as a way of possibly measuring and evaluating mental retardation. People were aware...that conventional tests had poor predictive validity, meaning that they didn't tell you much about mental ability.'' This intrigued Zelazo, currently professor of psychology and associate professor of pediatrics at McGill University in Montreal, and head of the department of psychology at Montreal Children's Hospital. It also provided him with a field of research. He knew that once there was a method to predict mental development in young children in what he called a lawful way, it would be carried out to the point of changing clinical practice. Zelazo and colleagues believe they have come up with that method. Their diagnostic tool, called the Information Processing Procedure ( IPP), permits identification of intact mental ability in the face of pervasive developmental delays and autism. It also makes possible a differential diagnosis for children who do not speak, have severely immature social interactions, disruptive noncompliant behavior or immature object use. Zelazo explained: "The primary thing we try to do is evaluate whether the child has the capacity to create mental representations for events that they experience. both visual and auditory events. And more importantly, whether they do that at an age-appropriate rate." "Early assessment of mental ability in young children has been guided by sensory mode and theory. which means that intelligence is in the action. But research on the measurement of a child's capacity to create mental representations, for example, is a very different theoretical formulation." "That's now the approach I think is so important, particularly with respect to autism," Zelazo stated. And it's that research that provided the impetus for IPP's development. "What we're able to do is make a differential diagnosis to determine whether the child's delays on conventional tests are a function of slow mental ability or impaired processing," Zelazo said. "Or if there is intact processing, the implications are that the problems are experiential in origin, that they are peripheral, more on the level of expression. Now that's the hypothesis we've been after." Intact and Impaired Processors To test this theory, Zelazo did a study with Richard Kearsley of the Center for Behavioral Pediatrics and Infant Development at Tufts University School of Medicine. They took 44 families of children, all delayed on conventional tests, and provided a treatment designed to create compliance where there was noncompliance, and to foster and stimulate expressive language in the hope that those children could catch up if the intervention was aggressive and consistent. They found they could sort children into intact and impaired processors. Further, they could predict that intact processors would make greater improvement, because the treatment was designed to deal with the peripheral developmental delays-expressive delays. Also, they detected a problem on the expressive level for children with intact processing. They postulated that those children could, in principle, catch up because IPP was not varying their intelligence, but rather giving them the means by which to express their intelligence. "That was confirmed with 61% of the children in the intact processing group," Zelazo noted. "Sixty-one percent were able to catch up with this aggressive treatment designed to improve their compliance so they could then imitate, so they could then develop expressive language. "The other critical piece of information is that in the sample of lab children with autistic features, three out of four of the children had intact processing. The impaired processors did not make any substantial gains, in fact, their delays increased with age, so you could expect there was a central processing delay. These, I believe, are the truly mentally retarded children." A Differential Diagnosis The results of this study gave Zelazo what he had been seeking-a differential diagnosis. A diagnosis that was confirming what current research was postulating-that in autism there are both forms of etiology-some children have a biological basis for it and some have a psychiatric or psychological basis. "I think that our assessment procedure allows us to parallel that," Zelazo said. "It seems as though those children with impaired processing have some kind of biological limit, whereas those with intact processing have some sort of behavioral dysfunction that is seemingly as persistent as the biological. What I am suggesting is that there is something you can do about autism with early identification and treatment; our testing procedures allow us to identify which children will benefit most." Zelazo's IPP was recently discovered by George R. Niemann, Ph.D., president and CEO of Bancroft, a nonprofit corporation in Haddonfield, NJ., serving individuals with special needs. Niemann said, "We were actually looking for a way to predict whether or not we could be more successful with some of the treatment interventions we use with children with autism. Our work [at Bancroft] involves treating children with very challenging disabilities, and we needed a way to see whether or not we needed to improve what we were doing. In other words, to get more predictive validity to our technique."
Zelazo concluded: "What the IPP allows us to do is identify children who demonstrate strong mental abilities even though they cannot communicate. These children have the greatest potential to overcome autism."
|
