system
Given the following post, respond as if you're commenting on Reddit:
human
[Doctor Who] Could an artificial intelligence beat a Silent's defenses?

Mainly, their ability to make anyone who's seen one forget about it as soon as they look away. Now because the Silents evolved this ability to piggy back off of other species, we know it is a biological function. So it evolved to work against the brains of other organic beings. It seems that the Silents affect the "recall" function of the brain's memory storage. They don't destroy the memory, but rather disrupt the retrieval of those memories. Once they're observed, all the memories of their race come back. This is known in psychology as "cued recall."

However, an artificial intelligence's memory works differently than an organic being's. Where memory in organics is a vague collection of chemicals, memory in computers holds a specific location on the drive, and is represented by a numeric sequence. If the memory drive could be accessed, then all the memories on it could be accessed. (Please, correct me if I'm wrong, I'm not that knowledgeable about computers, or neuroscience. This is my basic understanding though.) 

So, my understanding is that the Silents never evolved to deal with synthetic beings, making this a massive Achilles' heel for them. It worked fine on Earth, since humans weren't advanced enough to build an artificial intelligence, and the Silence would probably discourage them from doing so. However, any other advanced species they encounter would have an effective way of detecting them.

TL;DR K-9 is a dick for not warning the Doctor.
gpt
If an AI's memory is entirely mechanical or electrical (or similar) in nature and not biological, they would be immune. Remember, when the doctor inserted the "You should kill us all on sight." recording into the NASA broadcast, he made it clear that exact footage would endure for centuries and that humans would eventually and unknowingly drive the silents to extinction. That would mean every copy of the recording on video tape, then CD/Hard drives, the internet and other future recording device would "remember" the silent on screen. It's just data in a physical or electronic medium. 

For example, human cylons would be fully vulnerable to the memory loss, since their "parts" are organic. (well, most of them) A droid from Star Wars wouldn't. 

And who's to say K-9 never warned the doctor? It's not like he would remember it happening.