2

In this video (around 9:45 into it), the narrator says one effect of being limited to the left hemisphere of the brain was that, without noticing it, one will lose the ability to describe the right side of someone's face. I don't know what to call such a phenomenon, so I can't find any evidence of this, although [1] looks like a promising place to start.

Can those limited to the left side of their brains only describe the left half of one's face?

Sklivvz
  • 78,578
  • 29
  • 321
  • 428
Jacob
  • 149
  • 4
  • 1
    I think you are talking about [Hemispatial Neglect](http://en.wikipedia.org/wiki/Hemispatial_neglect), also known as _Unilateral Neglect_. I remember reading about it in one of [Oliver Sacks'](http://en.wikipedia.org/wiki/Oliver_Sacks) books. – Oliver_C Dec 12 '12 at 10:25
  • [Here is a clip](http://www.youtube.com/watch?v=ADchGO-0kGo) from a __BBC documentary__ about this phenomenon. – Oliver_C Dec 12 '12 at 10:32

1 Answers1

4

Can those limited to the left side of their brains only describe the left half of one's face?

In the diagram below you can see that the left side of each retina (which, due to inversion by optics of the eye, receives the right side of the field of view) is connected to the left hemisphere of the brain. However you would think that a person with right hemisphere damage could just direct their gaze to bring both sides of the subjects face into view on the left side of their retina.

nerve connections

However the problem is real. See Hemianopsia, Hemispatial Neglect and Fresnel prisms--their value in the rehabilitation of homonymous hemianopsias

a stroke affecting the right parietal lobe of the brain can lead to neglect for the left side of the visual field, causing a patient with neglect to behave as if the left side of sensory space is nonexistent (although they can still turn left). In an extreme case, a patient with neglect might fail to eat the food on the left half of their plate,


From Scholarpedia

enter image description here

Eye movements during visual search in an individual with left-sided neglect attempting to find letter Ts among Ls. Red dots show fixations and yellow lines depict saccadic eye movements from one fixation to another.


Footnote:

This is a partial answer, I don't know any sources that answer whether damage to one occipital lobe invariably leads to hemispatial neglect.

RedGrittyBrick
  • 24,895
  • 3
  • 100
  • 111