How the brain controls drawing and handwriting

And why tracing is a very bad idea

First a practical activity

Lets explore, in a practical way, how movements are controlled by the brain interacting with the joints and muscles of the arm and hand. 
 
For the activities you will need:
Several sheets of A4 paper
A pen or pencil
A black permanent marker pen

Experienced hand writers can write a sentence without needing visual guidance 

On a sheet of paper, write the following sentence, first with your eyes open, and then with them closed:  The sun is shining today.
 
Most likely your handwriting is much the same as usual with your eyes closed.  The words are probably well spaced as well. 
 
handwriting sentence with eyes closed.jpg
 

This is because fluent and efficient handwriting is produced with minimal need for visual feedback. 

 
Now produce two lines of handwriting with your eyes closed: Today the sun is shining but we are expecting it to rain tomorrow.. 
 
Handwritng 2 lines with eyes closed.jpg
 
Take a look at what you have written. Most probably each word is quite well formed.
 
Does your writing starts to slope one way or the other? Was it difficult to tell when you have reached the edge of your paper and also where to start the next line?
 
Visual monitoring of handwriting is important for positioning of the handwriting on the page and keeping the writing in a straight line. 
 

Letters are formed by a series of strokes 

Use a black permanent marker and copy the following letters: a, o, h, m. Write them large - about 3 cm high. 
strokes and letters.jpg
 
Now turn your paper over and take a look at the letters. You will notice that each letter has several small spots. These spots mark the place where the pen has slowed down on the paper between each of the small movements (strokes) that make up the letter.
strokes and letters reverse side.jpg
 
Each stroke is a separate movement with a beginning and an end. The small spots you see on the letters mark the points in the movement where the pen slows down at the end of one stroke and before initiating the next stroke.

Letters are formed by a series of small movements called strokes.

The pattern of movements (strokes) needed to form a letter are stored in the brain as a motor plan. 

The motor plans (also referred to as representations)  for each letter contain information about the  relative length, direction and sequence of the strokes needed to form the letter. 

In fluent handwriting the movements are pre-planned and carried out without the need for visual monitoring or feedback from the muscles. In fact research has shown that after the first few months of handwriting young children not only pre-plan letters, but have started to pre-plan whole syllables. 

The equivalence factor: writing big or small uses the same motor plan

Take a sheet of paper and turn it sideways. First sign your name at the top of the paper in your usual size.  

Next sign your name so large that it spans the width of the paper.  To do this you probably kept your fingers still and moved your hand across the paper using shoulder and elbow movements. 

Below there is an example of a signature written both small and large.  They look pretty much the same yet  the small signature was written using finger muscles and the large one was written using shoulder / elbow movements. 

This is because I have used the same, very well learned motor plan to control the actions, but have increased the size of the letters by sending signals to a different sets of muscles.

Learning to print letters is all about learning the motor plan for the letter

Learning to write a letter is a process of learning the relative length, direction and sequence of the strokes that form the letter and storing this information in the brain as a motor plan.e. 

When a letter is well learned  seeing an example of the letter (grapheme ) or hearing the letter (phoneme) will call up the motor plan for writing the letter.  
 
With repeated the practice the link between seeing, hearing or thinking about a letter becomes more direct, efficient and faster and requires no attention.  
 
When learners have acquired the motor plan for a letter they are able to write the lit without hesitation.  Learners who have not developed a direct link between the letter and the motor plan will hesitate before writing a letter.  

How tracing changes movement strategy

Below is an example of a circle drawn freehand 
Tracing a circle.jpg

And here is the circle I drew by tracing over the free hand circle. Notice the many changes in direction. Looking at the reverse side of the paper you can see the many stops indicating how I drew the line as a series of segments.

Tracing a circle 2.jpg   Tracing a circle 1.jpg

Tracing letters inhibits learning the motor plan

Many handwriting workbooks provide young children with outlines of letters to trace.  The outlines often have arrows to indicate the direction of the stroke. 

tracing letters worksheet.jpg

It is important to remember that learning to write letters starts with learning the motor plan for the letters and being able to fluently link the successive strokes to form the letter.  Once the child has mastered linking the strokes, the next step is to learn to moderate the movements to produce a letter of particular size. This takes quite bit of practice before a child can plan and control the movement so that the letter fits neatly between predetermined line. 

However when a letter is drawn within the confines of an outline, the motor strategy is very different. The child draws a series of short segments and visually monitors the actions to keep between the lines. 

Roan (Gr R, second term) has learned the correct stroke patterns for the majority of the letters of the alphabet, but has not yet learned to moderate the size of the letters. It is interesting that she does have quite good spacing between the letters which means that she is able to pre-plan the letter and select the correct start position for each letter. 

R-6y-alphabet_1.jpg

Here you see my efforts to trace a letter. The lines are not fluent. Because the shape of the letters differs from my usual pattern I need to my movements repeatedly to fit between the lines.

tracing letters_1.jpg

This has two negative consequences. The first is that the child starts to rely on visual monitoring of the writing actions. The other is that the child does not learn the motor patterns for writing the letter.

Children with good graphic skills do not seem to be negatively influenced by tracing practice. They learn the motor plan despite the tracing practice.  However for a child with poor graphic skills tracing letters has negative consequences. This is particularly true for children who tend to rely on visual monitoring of their drawing actions. 

Below is an example of a worksheet and letter tracing completed by a 6 year old in kindergarten. She in fact has quite fluent letter writing abilities, but this example shows how tracing the letter produces a jagged line as she attempts to conform to the outline of the d.

R dippy duck worksheet.jpg

For an alternative approach to teaching letter formation  Teaching handwriting - a stroke based approach  

Bibliography

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