Recap:

I have been concentrating recently, on trying to express my feelings through my watercolor studies. The closest I’ve come to attaining this goal was in a recent post (Adjusting). I had just experienced a major disappointment and was trying to feel better by painting a cheery picture. I was giving the paint-how-you-want-to-feel theory a try. The first phase worked: I created a picture with bright colors, which had an overall cheerful look. However, after the ‘second coat’ of paint, otherwise known in watercolor circles as ‘glazing’, my composition had an entirely different look. It looked the way I actually felt. I invite the reader to take a look at this post to get the full effect.

Today I would like to talk about illustration.  A quick look at Wikipedia yields the idea that an illustration is a depiction or representation of something seen, remembered or imagined. Illustrations are often used to simplify relationships among things that would be very difficult to do with words. To put it in terms of today’s parlance, illustration is akin to ‘data visualization’.

Altogether different topic

At the moment I am involved with another project, writing and editing an introductory neuroanatomy text with Andrew Lautin, M.D.. In the opening sections of our book, we follow the development of the neural tube from the closure of the neural groove, to the formations of the major flexures, invaginations and outpocketings that occur.

One major organizational principle of the neural tube was discovered early in the 19th century, independently by Sir Charles Bell, an anatomist and Francois Magendie, a physiologist. They found that the ventral (anterior) spinal nerve roots were responsible for motor functions and dorsal (posterior) roots were responsible for sensory functions. In the late 19th century (1888), Wilhelm His discovered that the neural tube was organized into district longitudinal regions along its entire length: a floor plate; roof plate; and lateral plates. The lateral plates were divided into a dorsal, or sensory, zone and a ventral, or motor, zone. His found a furrow that separated these two zones, which he called the sulcus limitans.

Back to illustration:

The illustration below represents the junction between the motor and sensory zones of the neural tube. I chose to use colors which are opposite to each other on the color wheel (the complementary colors, blue and orange) to indicate that the function on either side of the border (sulcus limitans), are opposite to each other (motor being the opposite of sensory). Although this is a trivial example of visualizing the difference between dorsal and ventral sides of the nascent central nervous system (CNS), I am trying to think of how to proceed from here to depict the CNS at more advanced stages.

Illustration – Sulcus Limitans
9″x12″ 140# Cold Pressed Watercolor Block