Earlier I told Tristan that although I wanted to reblog his post on split-brain perception and language, I was too bummed about the state of my thesis to have the heart to do it.  After working on my thesis draft for several hours straight, I feel like I’ve regained some composure and can once again appreciate the beautiful things in life, like neuroscience.  While it is 2:30 am on Wednesday here in Colorado, I’m sure that it is still Neuroscience Tuesday somewhere in the world.   So here we go: Split-brain surgeries- and later, experiments- are almost exclusively conducted on patients with severe epilepsy (makes you wonder if there’s a confound, what with their brains being extensively fried, but I digress…).  It’s interesting to compare a split-brain’s right and left hand productions (corresponding respectively to the left and right hemispheres) to the drawings made by patients with right and left hemisphere damage (see this post, for example). In patients with brain damage, the site of the lesion results in different types of visuospatial deficits.  Damage to the right hemisphere (causing left hemisphere dominance) results in the ability to notice detail but an inability to appreciate the whole.  In left hemisphere-damaged patients (right hemisphere dominant) there is a sense of the whole shape, but the details are omitted. A similar pattern can be seen in the split-brain patient’s drawings, above.  In the “left hand/right hemisphere” column of the split brain patient, you can see that the patient is trying to account for the 3-D shape.  In the “right hand/left hemisphere” the shapes are less accurate.  However, notice that the “right hand/left hemisphere” house has more windows, and notice that in the drawing of the cube, the patient tried to draw the inscribed triangle that is visible in the “example” cube.  The left hemisphere is noticing those details, but is still unable to incorporate them into a larger, coherent whole.   Cool.

Earlier I told Tristan that although I wanted to reblog his post on split-brain perception and language, I was too bummed about the state of my thesis to have the heart to do it.  After working on my thesis draft for several hours straight, I feel like I’ve regained some composure and can once again appreciate the beautiful things in life, like neuroscience.  While it is 2:30 am on Wednesday here in Colorado, I’m sure that it is still Neuroscience Tuesday somewhere in the world.  

So here we go:

Split-brain surgeries- and later, experiments- are almost exclusively conducted on patients with severe epilepsy (makes you wonder if there’s a confound, what with their brains being extensively fried, but I digress…).  It’s interesting to compare a split-brain’s right and left hand productions (corresponding respectively to the left and right hemispheres) to the drawings made by patients with right and left hemisphere damage (see this post, for example).

In patients with brain damage, the site of the lesion results in different types of visuospatial deficits.  Damage to the right hemisphere (causing left hemisphere dominance) results in the ability to notice detail but an inability to appreciate the whole.  In left hemisphere-damaged patients (right hemisphere dominant) there is a sense of the whole shape, but the details are omitted.

A similar pattern can be seen in the split-brain patient’s drawings, above.  In the “left hand/right hemisphere” column of the split brain patient, you can see that the patient is trying to account for the 3-D shape.  In the “right hand/left hemisphere” the shapes are less accurate.  However, notice that the “right hand/left hemisphere” house has more windows, and notice that in the drawing of the cube, the patient tried to draw the inscribed triangle that is visible in the “example” cube.  The left hemisphere is noticing those details, but is still unable to incorporate them into a larger, coherent whole.  

Cool.