Here's something self-indulgent from a while back

[yvannairie]

(Reposted from Tumblr)

Sparkbonded mechs can eventually learn to “ride along” each other’s sensory feed, even over long distances. It’s most likely to occur when one of them is in recharge (lack of other input), and the other one awake, so most don’t realise that’s what’s happening b/c at first the differences in sensory input parsing leads to an incoherent, dreamlike experience.

Over time, sparkbonding causes various subsystems to synch up, which will make the sensory experiences easier to parse, and may even lead to “phantom limb”-like sensations whle awake, especially between bonded pairs of different frame types and classes. The sensation source is rarely aware of the connection – for some people it can lead to feeling like they’re being watched, but even that is usually hard to distinguish from the general mutual “awareness” typical of a sparkbond. (Subsystem synch-up itself is actually a widely-known and understood phenomenon. Past a certain level of synch the difference is flatly detectable in vital functions to the point where it's regularly used as a diagnostic tool. )

Sensation transfer while awake is rarer, but it’s known to occur with sudden spikes in sensory or system activity, and the frequency at which they happen has a rough correlation with the percentage of system synch-up the bonded pair is experiencing. Data compression artefacting and junk data synch while in recharge (”dream sharing”) is considered a separate phenomenon from sensory transfer, and is a lot more common even among newly-bonded pairs.

(A lot of the literature about sparkbonding from the Golden Age has gone missing by the time the civil war starts and sparkbonding has been elevated to have this quasi-mythical status, but after the war th research picks back up and a lot of the superstitions start getting cleared up mostly due to an ample amount of cross-frame-class-and-type bonds to use as test cases. There still doesn't seem to be a clear rule as to what causes it, although some highly unscientific theories about attachment and 'missing' your partner have been floated >v>)