Consciousness and Aphantasia.

 

Some 97% of us can recall to consciousness -- can visualize -- a loved one’s face or the best meal or they’ve ever had or a  painting. But 3% of us do not have the ability to form a conscious image from semantic memory stored in the brain. This phenomena is is known as aphantasia.

Have you not watched a book adaptation on film or TV, and felt disappointed when a scene wasn’t quite how you’d pictured it? Or perhaps a character looked nothing like you had imagined them to look?

Now imagine watching the adaptation with no recall of mental imagery of what you read in the book. That is aphantasia.

 Yet people with aphantasia have intact spatial imagery ability; they have the ability to represent the size, location and position of objects in relation to each other. They can look at shapes to work out if they are the same shape rotated or different shapes as shown by the drawing in the image above.  

Test subjects with aphantasia were shown the image on the left and asked to make a drawing of it as they were viewing it. A typical result is the "From Perception" image they created in the center image on the right which contain a great deal of sensory information about shapes, objects and colors. But when asked to draw the image from memory, the image in the center on the left was the result. Typically theswe drawing contained on a few shapes in the same relative positions. 

Then the test subjects were asked to view a drawing of the scene shown as a line drawing of objects and shapes in it "From Perspective ", their drawings "From Memory" contained a great deal more of the objects and locations they previously saw  "From Perspective ". 

Once again, consciousness does not always present reality as a whole. In the case of aphantasia, conscioiusness from memory presents reality very than from reality. And, not only that, consciousness presents different aspects of of reality. In this case, the quale of color is completely missing and memory of objects is greatly impaired. A bed is represented in space as a series of line. 

The cause of aphantasia is the physical misconfiguration of neural cells in the brain which appears to be genetically linked to defects in the DNA that runs in families. And so it is that consciousness, once again,  is all about chemistry of the brain. No chemistry, no brain. No brain, no consciousness.