What does it mean to cross midline anyway? Your child’s midline is an imaginary vertical line down the body that divides it into two halves (a left and right side). When therapists refer to crossing midline, we are talking about children’s ability to use their arms and legs to reach across that line to the opposite side of the body. Children should be able to do this skill by 3-4 years old. If your child does not cross midline, you might notice him or her switching hands while completing activities such as drawing. Your child might also rotate his or her trunk to compensate for not being able to reach to the other side.
So why is it important to cross midline? When a child cannot cross midline, it means that the right and left sides of the brain are not communicating with each other efficiently. This prevents the brain from learning to coordinate movements properly. Furthermore, children who can’t cross midline may have trouble establishing a hand dominance (whether they’re right-handed or left-handed). Children should have a clear hand dominance by the time they’re 5-6 years old. When children switch hands to perform tasks, both hands get equal fine motor practice, so one hand doesn’t become stronger than the other. Children without a strong hand dominance often have trouble with handwriting, as they have two hands with mediocre strength and fine motor skills instead of one really strong hand and a weaker helper hand. It also makes it hard for children to perform activities that require bilateral coordination (using both sides of your body together for the same task). For example, the child might have trouble holding a piece of paper with one hand while cutting out a circle with the other hand. These kids tend to have difficulty reading as well, because they might have trouble using their eyes to track across midline. Difficulty with midline crossing doesn’t only affect academic work. When children can’t cross midline, they might have trouble doing functional skills like brushing their hair, trying their shoes, or buckling their own seatbelt. Furthermore, they might have difficulty doing larger, gross motor movements like kicking a ball, skipping, and swinging a baseball bat. So what can you do if you notice that your child doesn’t cross midline?
Here are some activities to try at home:
- During play activities, encourage and/or help your child to reach for objects on the left side of the body with the right hand and objects on the right side of the body with the left hand.
- Have your child bring his right elbow to his left knee. Then switch and have him bring his left elbow to his right knee.
- Have your child touch her right foot with her left hand and her left foot with her right hand.
- Toe Taps- have your child cross the right leg over the left leg, tapping his right foot on the outside of the left foot. Try the same thing on the other side.
- Have your child try to draw a large infinity symbol (looks like a sideways 8) with only one hand and without rotating his trunk. Or, have your child drive a toy car in the same pattern on the floor.
- Try playing sports like baseball, tennis, soccer, and hockey at home. Don’t have the right sports equipment? Improvise! Try using a pool noodle (cut in half) as a baseball bat and a balloon as the baseball.
Most importantly, make it fun! Play is how children learn best, so don’t make these activities a chore.