The vision is lost in halves that are contralateral to the posterior cerebral artery that is affected.

视野缺失会受影响的大脑后动脉的对。

Now, normally damage to brain tissue results in weakness on the contralateral side, so, the Kernohan’s notch causes a false localizing sign.

通常情况下，脑部损伤造成的肌肉无力占对，所，Kernohan切迹会导致假性局灶征象。

So that means that each facial nerve contains motor information for the lower face coming from the contralateral motor cortex, and motor information for the upper face coming from both motor cortices.

也就是说，每条面神经包含两种运动信号：1.控制下半脸的运动信号，来自对运动皮质；2.控制上半脸的运动信号，来自双运动皮质。

This causes paralysis of only the lower half of the face on the contralateral side as the lesion, since the upper half of the face is still receiving some information from the ipsilateral motor cortex.

这类病损只会导致对下半脸瘫痪，因为上半脸仍然能接收一些来自同运动皮质的信号。