Brain-imaging maps show differences in blood flow (a measure of brain activity) between children with autism and typically developing children during right-handed finger sequencing (RHFS; red), left-handed finger sequencing (LHFS; blue) and the overlap between RHFS and LHFS (pink).  The upper maps show regions where typically developing children showed greater activation than did those with autism; the lower maps show regions where children with autism showed greater activation than the other children. (image courtesy of Daniel Simmonds)
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In Autism, Movements May Not Quickly Become Habit
By Faith Hickman Brynie
 June 26, 2009

As their parents can attest, children who have autism seldom excel at sports. Although often skilled in manipulating numbers or memorizing facts, these kids often prove clumsy and awkward in athletic pursuits.

Stewart H. Mostofsky, a pediatric neurologist at the Kennedy Krieger Institute in Baltimore, may have found a reason why. In a study published online in the April 23 issue of Brain, Mostofsky reports that the brains of children with autism appear to work differently when performing a simple motor task, compared with the brains of typically developing children.

Mostofsky’s research team used functional magnetic resonance imaging (fMRI) to create images of the brain’s motor-control regions while 13 typically developing children and 13 high-functioning children with autism, all ages 8 to 12, performed a series of finger taps. Before they went into the brain scanner, the children were trained to touch, in sequence, their index finger, middle finger, ring finger, and little finger to their thumb. While in the scanner, they alternated left- and right-hand finger tapping with periods of rest.

During the finger-tapping exercise, brain activity increased in the primary sensorimotor cortex, thalamus, cerebellum and supplementary motor area (SMA) in both groups of children. Those brain regions are known to be associated with movements. However, activity in the cerebellum increased less in the children with autism than it did in the typically developing children. The cerebellum is the part of the brain that “takes over” when movements become habitual or automatic.

In addition, the children with autism showed a comparatively greater activation of the supplementary motor area, a higher cortical region that exerts “top-down,” voluntary control over movements.

These findings suggest that children with autism have trouble shifting responsibility for movement from the effort-evoking region, the SMA, to the cerebellum, where automatic control can take over. That would mean that while typically developing children are better able to rely on habitual motor systems; children with autism must continue to rely on the willful control of movement.

"We know that structural differences in the cerebellum occur in autism, but we don’t know much about how they affect the brain’s functions,” says Greg Allen, an educational psychologist at the University of Texas, Austin, who specializes in the diagnosis of autism but was not involved in this research.

“This study makes an important contribution: It confirms that the functioning of the cerebellum is compromised in individuals with autism, even when they perform a relatively simple motor task,” Allen says. “It also begins to shed light on how cerebellar changes affect connectivity with other brain systems."

Mostofsky and his colleagues also investigated connectivity, the ability of various brain regions to communicate with one another. Many anatomical, behavioral and imaging studies have suggested that localized, small-area connections “overgrow”—form more connections than normal—in the brains of people with autism, while connections among distant regions “undergrow.” These differences are termed “local overconnectivity” and “long-distance underconnectivity.” [See Dana story, “Autism and Motor Skills: A Matter of White Matter?” November 2007]

Mostofsky found evidence of long-distance underconnectivity in the children with autism. He measured faulty long-tract connections among the sensorimotor cortex, thalamus, SMA and cerebellum. “Decreased connectivity may reflect poor coordination within the circuit necessary for automating patterned motor behavior,” he says.

Mostofsky’s work suggests that imaging the brain during the performance of motor tasks may offer a way to diagnose autism earlier and may also help researchers find associations between autism and specific genes. The same neural processes that explain impaired control of movements could help explain how deficits in social and communicative skills arise, he suggests. His team plans to continue the research, looking at activation and connectivity while children are learning a new movement.

Comments

Study raises more questions
Tracee Pickett

6/27/2009 9:54:25 PM

Excelling at Sports for children is an effort of co-ordination and team work. First of all co-ordination takes practice and practice for typical children often begin at an earlier age then those with autism. Team work is a component of communication. Parents of a child that have been diagnosed with autism are often mesmerized in their thinking process which mostly leads the parent to over helping the child to the point that the child does not learn to do for themselves or in some cases not knowing how to assist a child in learning as they had expected to do in the course of raising a typical child if there is such a typical child in the first place.

Under-helping children can have varied results, leading to a child that does everything capable for themselves to sometimes frustrating a child. And well, typical children are treated most often with greater expectations of typical outcomes with the effort of their parent’s teachings and of course others along the way giving instruction. Sometimes and even more often than not the expectations that parents have of the child who has autism, in the earliest part of development, the expectation can be less, and therefore the parent expects less and brings less information to the tables of their autistic children than they normally might otherwise.

Also, children with autism may process at different rates than children without autism, or even in a different way that seems to take longer perhaps. These time differences in learning are unclear as to the child’s capability because of the nature of the earliest: contact, education, understanding of care and interaction, and /or instruction of a child with autism. It may be that the child has not had enough practice with small motor skills or even large motor skills to reach that total co-ordination point. The total co-ordination point meaning their “Automatic Network”, referenced in the earlier article.

What is most interesting about the article is the discovery of the “brain’s activity increase in the primary sensorimotor cortex, thalamus, cerebellum and supplementary motor area (SMA) in both groups of children”. Although it is not clearly stated in this article what the supplementary motor area is, where it’s located, and what difference the increased automatic network has on it in effect exactly. Though the fact that there is an increase in these stated areas only means that there is improved connectivity in the brain and to increase that connectivity with more practice to relatively average levels of connectivity would seem vary beneficial to all children and the study concludes that it is a possibility / even if the child with autism takes a little more time in getting there…

This article did not take into account that some children, whether they have autism or do not have autism, have varied differences in the way they learn and process. There are children in the world that do not begin to make attempts at using there skills until they have first intellectually digested more information than others before they begin the practice of the activity. I have not seen many children like this but some.

Many instructors do not understand this process because often that is not the way they might have learned. Often this misunderstanding by instructors leads to labeling the child with a learning disability or even further titling them as low-functioning or high-functioning which then further reinforces our own thoughts as doctors, research scientist, and educators, that a child is absolutely just that, low-functioning or high-functioning, rather than understanding their process and the difference in individual learning. This reinforced verbal course then sets the mind into revoking the process that we might provide without the label. The label then can be a set back internally to that child and the professional or parent, emotionally inhibiting the natural process of that child’s ability to learn.

Certainly we begin to understand a child’s differences as we work with that child, and it certainly is helpful to know of visual impairments and hearing loss and perhaps unusual abilities and differences. But we must be very careful in the labeling and the reinforcement that the labeling might carry to all individuals. Automating patterns of motor circuitry is a pure outcome of function of repetition in the thinking process and the practice of that process, which concludes that there is a connective brain activity included in that and is one of the greatest outcomes of this study.

One area that is not covered in the research is the interest levels of the children to that activity or a sport? This is something that must be considered when creating such studies. Though, let’s get back to the automated pattern. The question is, how is that done? And how do scientists make these connections to what their research uncovers and how is it then applied by scientist without outside sets of knowledge from good instructors who might have more complete knowledge of the learning role and then of course others professionals that cross over into the many areas that these sciences cover? And we go back to how that is done?

Well, research has already told us that the practice of musical instruments increases automated patterns in the brain. It shows up in higher aptitude for mathematics, but it also increases automated motor repetition with small motor skills as there are also many activities to assist and enhance small motor skills. Large motor ability is achieved of course by larger motor activity. Kick ball, track and field, walking in the park, jumping, dance, actions in a gymnasium, swimming,… Are these areas being conclusively studied when we make attempts to discuss whether the brain has the ability to conduct automated responses when given ample opportunity to first: have enough time to individually learn and then practice those responses?

The most interesting part of the article is that there seems to be information about the way in which an autistic child hears as it would be related to tapping the fingers. If the activity of say drawing was used instead of tapping the fingers as tapping the fingers is often related to music rhythm, then are there differences in the way an autistic child might be hearing as we might first ask if the children can use their, studied areas or practice, to doodle the same image over and over and make sure the original study results in the same? Or is it just a function resulting from interaction, influence and studied practice? In further study of the actual components of the activity, we might uncover the area of which could be the main obstacle for children with autism and then more completely understand how to better instruct children with autism as well as children without autism.

My last interest is in the hypothalamus gland which I’ve read has some correlation to depression if injured. Although I’m not an expert in this area, my question to neuroscientists is, if these automated patterns show more brain connectivity, what happens when someone has increased automated activity then some how loses that or decreases the activity: could this cause the opposite to happen and then cause depression? That is, I guess, my question of the day. And to conclude my commentary, The Dana Foundation and its contributors make wonderful discoveries. I’d like to add, with more contribution to the neuroscience research through other areas like arts and teaching, one day the field of neurosciences could become a completed area of research, though with all the variables, it will be some book….