Why does my cat get aggressive when I'm inhaling loudly?

Question

Recently I've realized that my cat gets very nervous, and even aggressive, if she hears me snorting loudly several times, even when she's a long way away from me.

If I start doing so, she immediately becomes more alert, moving fast from one place to another and, if I keep it doing for a while, she comes running towards me and tries to sit on me sniffing over my face and even putting her paw on my mouth.

She's never been in a conflict with another cat and of course we've never beaten her nor used any physical punishment over her. What might be the reason for this behavior?

---- EDIT 1 ----

Additional things about that I'm sure of: The position of her ears are straight, but when this happens she adopt a tense body posture.

---- EDIT 2 ----

Last night my girlfriend and I did some tests and, definitely, she finally gets very angry. When I started snorting she started being very active, running from one place to other, and even something she had never done before: rolling while face up on the floor. When I continued doing so, she started jumping from one chair to another and after awhile came over to me and I got a good chunk taken out. So, definitely, yes she gets aggressive and now I really doubt it's concern is what she feels.

Now that I have done this experiment, I determined some more physical details: the ears, as I said, were straight all the time except when she came to bite me, then she put her ears backwards. Her tail was in a "normal" position all the time she was jumping around, but when she attacked me, she raised her hackles.

I didn't want to stress her more so I didn't made any further try but definitely she doesn't like hearing me snorting.

Answer 1

So, cats can be fairly vocal animals and many of their vocalizations have some meaning with respect to how they may respond. The ones that indicate a level of aggression include:

• Growl, which is usually low-pitched, harsher, and short in duration and mouth is open. Is usually an antagonistic sound.
• Hiss, which is usually open-mouthed and has visible teeth.
• Snarl, which is very similar to a growl, but higher pitched.

If your snorts (or the aftermath of them) sound like the above to her, it could be taken as aggression by her and so she could react accordingly. If you're conscious of this and see her reacting, then some steps to try are:

1. Stop the activity.
2. Try to vocalize a murmur (kind of like a purr) sound with your mouth closed.
3. Provide some visual clues that you're not antagonistic such as slow blinking which is sign of relaxation in a cat.
4. Reward her with a treat if she calms down.

Basically, this is calming the situation and teaching her that when this happens, you're not being aggressive.

Do not:

1. Make sudden moves or try to grab her.
2. Open your eyes fully.
3. Keep your mouth open.

The above are seen as aggressive and will exacerbate the situation.