Caloric Test

[MudPhud20XX]

Alright, so some of you are familiar with the mnemonics COWS: cold opposite, warm same.

Can anyone please explain why this is the case?

So I get rough idea here:

When you stimulate the Lt. CN8 nuclues, you stimulate CN6 contralaterally and CN3 ipsilaterally and move your eyes to the Rt.

But why is this different when you stimulate the ears with warm water?

Also, has anyone done this? I don't think I would see this kind of reaction when I try to put cold/warm water in the patients' ears, I mean does this really happen?

---

Members don't see this ad.

 

[Miracoli]

WARM SAME direction of the FAST component of nystagmus

warm H20 in the RIGHT ear -->this is seen as if there is stimulation vestibular labyrinth in the right-->increase frequency of APs in the right CN8 and vestibular nucleus-->contraction of RIGHT medial rectus by RIGHT CN3 [ adduct the right eye] and LEFT lateral rectus by LEFT CN6 via MLF[abduct left eye]--> both eyes look to the LEFT(slow component of the nystagmus)
but the cortex realizes the head did not move to the right so left frontal eye field(FEF)--> right PPRF-->stimulation of right CN6 and left CN3 via MLF-->both eyes look to the RIGHT(Fast or corrective phase of the nystagmus)
Comprende?