Conference News Update

The child was evaluated one month after locomotor training and then annually for four years. With the help of a rolling walker, he walks independently and can achieve speeds of nearly twothirds of a meter per second. Without further training, he learned to pedal a tricycle, crawl, climb stairs, and swim. He reported improved bladder sensation and attended elementary school full time without a wheelchair.

But, despite his functional improvements, his lower extremity motor score never changed—he remains unable to perform isolated leg joint movements even though he walks full time. “The idea is that there may be a small subset in the spinal cord injury population who can benefit from training and whom we have not identified, and the reason we have not identified them is that the traditional way isn’t informing us,” Dr. Behrman said. “These are all severely injured kids. Just think across the lifespan of a child who may be 3, or 6, or 10 years old at the time of injury, what a difference it would make if he or she could regain a fraction of mobility.

Even better trunk control means quite a bit—pushing a wheelchair or sitting behind a desk more comfortably can be very important.”

Children who participated in the studies were assessed before and after locomotor training for sensory and motor function, gross motor skills, ambulation, and crawling. Lab-based tests were used to evaluate the integrity of connections between the motor cortex and spinal cord, as well as between the subcortical structures and the spinal cord. The recovery of such function may be associated with the integrity of these neural structures and poses a new means of predicting walking recovery in the most severely injured children.

The results suggest that locomotor training and walking recovery may be linked to the development of other rhythmic, reciprocal lower extremity tasks that together promote healthy growth and development.

“This doesn’t mean all kids with these severe injuries can improve from this intervention, but there is likely a subpopulation that can regain mobility, whether walking or trunk control,” Dr. Behrman said. “Our aim is to provide clinicians with a means to identify who may benefit among the population with spinal cord injury and thus predict who will respond.”

Mental Introspection Increases as Brain Areas Begin to Act in Sync

Researchers have shown with use of fMRI why behavior in children and young adolescents veers toward the egocentric rather than the introspective. According to the investigators, the five scattered regions in the brain that make up the default-mode network (DMN) have not started working in concert in youngsters ages 6 to 9. These areas light up in an fMRI scan, but not simultaneously. The DMN is only active when the mind is at rest and allowed to wander or daydream. This network is believed to be key in how people introspectively understand themselves and others and form beliefs, intentions, and desires through autobiographic memory. By ages 10 to 12, these diffuse regions start functioning together as a unit, and at ages 13 to19, they act in concert, as in adults.

“These results suggest that children develop introspection over time as their brains develop,” said Stuart Washington, PhD. “Before then they are somewhat egocentric, which is not to mean that they are negatively self-centered, but they think that everyone views the world in the same way they do. They lack perspective in that way.”

Previous research has suggested that the DMN is not well synchronized in many patients with autism, and this may explain the perceptions that many of these individuals express in testing—a viewpoint that is also seen in younger children who do not have autism, Dr. Washington said.

The research team enrolled 42 participants—10 individuals were ages 6 to 9; 12 were ages 10 to 12; nine were ages 13 to19; and 10 were ages 22 to 27. The investigators’ goal was to study the development of functional connectivity between the anterior and posterior nodes of DMN across the four age groups.

They gave the participants a task to perform, but the researchers were interested in recording brain activity that took place after the task was over, when the patients were told to rest. In the group of children ages 6 to 9, the researchers saw the same kind of lack of synchronicity seen in older autistic children, Dr. Washington said.

The older participants in this study were, the more that the DMN functioned in sync, reaching a plateau in adulthood, he said. Significant differences were noted between children and adolescents and between children and adults, he added. “These increases in functional connectivity coincide with introspective mental activity that has been shown to emerge during adolescence,” Dr. Washington commented.