The brain is made up of two hemispheres. Very roughly speaking, parts of the left hemisphere are involved in moving the right side of your body and seeing things in the right field of vision. Likewise, parts of the right hemisphere are involved in moving the left side of your body (e.g. left arm or left leg) and seeing things in the left field of vision.
On the Magnetic Resonance Imaging (MRI) scan of my brain, white spots could be seen in the (right) internal capsule which is deep in the brain and contains a bundle of nerves or “wires”. These wires send signals between the brain and, for example, the limbs (for movement) and send information from your eyes to your brain (for vision). The internal capsule is a common area to be affected in patients who have had a “stroke” (CVA; cerebrovascular accident) which is why a stroke was my initial diagnosis, and not multiple sclerosis (MS). I couldn’t move my left arm or left leg because the damage in the right side of my brain prevented motor (movement) signals getting to my left limbs. Even the left side of my face couldn’t move. I could not see anything on the left side through both eyes because sensory (visual) signals were not getting through the wires in the brain. In other words, I could only see the right side through my right eye, and the right side through my left eye. Confused yet?! Each eye can only see the right side. This is called hemianopia.
I could see the right visual field but couldn’t see anything in the left visual field. Imagine a clock split into two halves, I could see the numbers 12 round to 6 on the right half, but the left-hand side of the clock did not exist. People have asked me why I just don’t turn my head round to see the left side. This does sound pretty logical to me too but it doesn’t matter if I turn my head, my eyes still refuse to move to the left and that side simply does not exist for me. Similarly, when I read, I often miss the first few letters of each word. This has its funny side because, as a counsellor/therapist, I am often shocked when, instead of reading the word “therapist”, I see the word “rapist”!
The left side, however, is NOT black like the image above and I am therefore not aware of the fact that I am missing something. The strange thing is that I forget that the left side even exists! This is called hemineglect. I totally neglect the left side of my body, the left side of my visual field and no matter how many times I tell myself to remember, I still forget to pay attention to the left side. This is why I cannot ever cross the road without a zebra crossing or traffic lights. If I am walking, I have to continuously remember to lift my left leg but often trip or stumble because, in that split second, I forgot to lift it.
Finally, I only see the right side of people’s faces and the right side of their body. This means that I don’t see people waving at me with their right arm (which is on my left side!) and often don’t recognise them at all, especially if they are in a busy environment. When I look in the mirror, I only see the right side of my own face and haven’t seen the left side for years! I wonder if that side has less wrinkles?!
Next time, I shall talk about myelin, the fatty coating around the neural wires in our brain and possible ways to help it repair itself. If you liked this, be sure to subscribe. It’s free and you will have access to my weekly blogs. If there are specific areas of interest that you would like me to write about, please comment or write a question and I’ll do my very best to answer. I would love to hear from you!