Hearing & Distinguishing Specific Heartbeats

[Flyndaran]

I always took most examples of hearing heartbeats in fiction as euphemisms for detecting life. Like Wolverine's low grade psychic abilities referred to as smelling... even for things that are impossible to smell.

[JCurwen3]

Originally Posted by Flyndaran

I always took most examples of hearing heartbeats in fiction as euphemisms for detecting life. Like Wolverine's low grade psychic abilities referred to as smelling... even for things that are impossible to smell.

Sometimes they hear them well enough to know whether a specific person is there (an individual's heatbeat, measured on an EKG, is close to unique), or use their hearing of the heart rate to detect lies or stress (the latter most notably recently on both Alphas and The Vampire Diaries). Definitely goes beyond the ability to detect life (beyond, and yet below too, as it would miss any organisms without beating hearts - which includes all plants and insects and single-cells, as well as even some humans that have been given recently developed pulseless heart transplants). Plus it almost always goes hand in hand with being able to hear all super-faint sounds (or else it isn't presented as "hearing" at all but rather a life or blood sense).

[Flyndaran]

Except that simply hearing a heart beat will not allow all those super abilities.
A trained polygraph expert needs a whole suite of measurements to get a best of 70% accuracy for detecting lies.
Individuals heartbeats aren't so individual that simply hearing for a minute would allow one to identify people. EKGs require hours to detect some problems, and no doctor I've heard of can identify an individual from those, and they are far more detailed than a simple lub dub hearing.

It's the issue of giving a character one almost plausible ability, before doing the math, and then tacking on a whole suite of super abilities that almost sound like they could grow out of the first, again before doing the math and analyzing it fully.

The character may believe what he's sensing is the target's heartbeat, but that might be correct.

[jeff_wilson]

Originally Posted by Flyndaran

Except that simply hearing a heart beat will not allow all those super abilities.

The reception would need to be upgraded until the character of the heartbeats were detectable, like being able to hear someone speak clearly instead of just being able to hear noises with speech cadence.



When does Wolverine smell the unsmellable?

[BaHalus]

Ok, it really is seeming that is not a ability that can be build as acute hearing alone, but discriminatory hearing would not be enough?

Discriminatory smell is not enough to do a wolverine-like detection and identification?

[vierasmarius]

Originally Posted by BaHalus

Ok, it really is seeming that is not a ability that can be build as acute hearing alone, but discriminatory hearing would not be enough?

Discriminatory smell is not enough to do a wolverine-like detection and identification?

In general, I'd say no. My approach would be to build it as Detect and Discriminatory Sense as Alternative Abilities to each other. You build powers based on their mechanical effect, not their in-setting justification.

[white33]

Originally Posted by Flyndaran

Except that simply hearing a heart beat will not allow all those super abilities.
A trained polygraph expert needs a whole suite of measurements to get a best of 70% accuracy for detecting lies.
Individuals heartbeats aren't so individual that simply hearing for a minute would allow one to identify people. EKGs require hours to detect some problems, and no doctor I've heard of can identify an individual from those, and they are far more detailed than a simple lub dub hearing.

It's the issue of giving a character one almost plausible ability, before doing the math, and then tacking on a whole suite of super abilities that almost sound like they could grow out of the first, again before doing the math and analyzing it fully.

The character may believe what he's sensing is the target's heartbeat, but that might be correct.

That's a non-argument and completely besides the point.
It's not an issue of the heartbeats themselves being all that distinguishable, but of the character's sense being so incredibly accurate he can distinguish them in such a manner.
Also, i don't think we're necessarily going for pinpoint realism here... The trait can be built, or it cannot, the concept is clear and solid enough, "reality" being flexible in this context.

As for OP's request, it's clearly supposed to be a relatively simple hearing based trait. Think of fiction, Superman for instance could easily accomplish such a feat(i'd guess he probably has at some point), and he does so because of his "super-hearing", not because of his exotic, weirdly specific and quite "meta" detecting "X" power...
So, to break this down, this trait has, IMO, 3 basic parts.
First you need to have hearing powerful enough to allow you to hear heartbeats in the fist place; Second you need to be able to filter and distinguish sounds in order to target what you want to hear(in this case, the heartbeats); Third, you need to somehow be able to detect and distinguish minute differences within the heartbeats you hear in order to draw conclusions from them.
The first and second part are generally easy to build in a number of ways, some already suggested in this thread, the third bit is the issue. Ideally, IMO, it should be built as a skill related to this "super-hearing" advantage, at least that's how i'd envision this working as a concept, but i'm not sure how to best simulate that, or to build this in a non-broken way, since making skills that work based on advantages/powers can be problematic.

[JCurwen3]

@Fred Brackin & NineDaysDead:
Thanks for those links, they are extremely helpful!
@Bruno:
Thanks for pointing me to the High Tech hearing table / rules. Much better / more helpful than the one in Basic Set. Also reminded me of some additional Sense Modifiers rules in Mysteries.

So I think I'm close to my goal.

Originally Posted by Flyndaran

Except that simply hearing a heart beat will not allow all those super abilities.
A trained polygraph expert needs a whole suite of measurements to get a best of 70% accuracy for detecting lies.
Individuals heartbeats aren't so individual that simply hearing for a minute would allow one to identify people. EKGs require hours to detect some problems, and no doctor I've heard of can identify an individual from those, and they are far more detailed than a simple lub dub hearing.

That may be true. But GURPS has a Detect Lies skill, and with enough points in that skill you can get a far better than 70% accuracy without (1) a polygraph or (2) the benefit of actually hearing that their heart rate increasing. Also, I've seen polygraph experts at work, and although the machine is very important, much of the time the polygraph expert is basically using intimidation / interrogation thinly veiled as an innocent line of questioning; they can seem a bit like mild bullies.

I thought for the ability to detect lies, I'd add Empathy (Sense Based, Hearing) to the build, which would give a +3 to Detect Lies and other relevant skills that would also make sense to get a bonus. To be good at it, they'd need to invest in Detect Lies, but the +3 would make it easier. On the other hand, without investing in that skill, based purely on their superior hearing they could at least hear that the heart rate had become faster... which could mean anxiety, lying, arousal, fear, other emotional state that gets the heart racing, they just physically exerted themselves... or they have some heart problems. Situationally, one could make inferences, of course without any necessary guarantee you're right.

It could be mildly useful, maybe, at quick on-the-spot medical diagnoses. Probably want limited Animal Empathy too if I want to make better guesses about animals based on their heart rate.

As far as identifying an individual's heartbeat from a crowd, I read a couple of papers today that discussed heartbeat characteristics as being unique (or pretty close to it) and possibly even being an identification biometric instead of or in addition to fingerprints. I'll try to find them again and post the links.

Of course, though, you're probably right about it requiring more than a minute to memorize an individual heart's signature, especially since the heart rate whilst studying the target might be significantly slower or faster than when you "listen" for them later; that wouldn't make it impossible, but it would make it more difficult. I guess I could add Reduced Time to Discriminatory Hearing to make it faster to memorize - maybe 60 times less to reduce normal memorizations to take a second and then a minute or a so to memorize heart signatures. Alternatively, I could have an -80% limitation on Photographic Memory for just sampling hearts... which I think would cover quick, effective memorization of heartbeat signatures. Or, I could go even simpler and call it a perk to memorize a heart's unique sound quickly, say, within a minute.

Originally Posted by Bruno

Parabolic Hearing will let you filter out ambient noise penalties at a 1:1 ratio <snip> EDIT: I misremembered, it halves effective distance. Still something to consider.

Parabolic Hearing vs Acute Hearing... what can Parabolic Hearing do that Acute Hearing can't (or does less effectively), and vice versa, and where do they overlap?

For instance, I think (just doing a casual look) that Parabolic Hearing might be better (cheaper) for hearing at a distance. It also seems to suggest that it can ignore background noise. To ignore, for instance, the -5 from traffic background noise would require 5 levels of Acute Hearing to cancel out, but I'm not sure what, if anything, Parabolic Hearing will do to that penalty, and at what level to ignore it.

I'm pretty sure things like hearing through barriers (like walls) can only be improved by Acute Hearing but not at all by Parabolic Hearing.

Basically, I guess I'm a bit confused when to use one and when to use the other to overcome the various penalties to hearing rolls.

[vicky_molokh]

Actually, the Hearing rules are still puzzling to me. Here's what I could gather:

Let's say Conversation has a volume level of 60dB 'at the muzzle'. That means that at 16 yards, a person can hear a conversation with a Hearing-4 roll. Add -5 for a busy street or -10 for fireworks.

So it requires Hearing 19 to have a 50/50 chance to hear a normal conversation in a busy street at 16 yards. And then an IQ roll to understand it. Harsh?

[JCurwen3]

Originally Posted by vicky_molokh

Actually, the Hearing rules are still puzzling to me. Here's what I could gather:

Let's say Conversation has a volume level of 60dB 'at the muzzle'. That means that at 16 yards, a person can hear a conversation with a Hearing-4 roll. Add -5 for a busy street or -10 for fireworks.

So it requires Hearing 19 to have a 50/50 chance to hear a normal conversation in a busy street at 16 yards. And then an IQ roll to understand it. Harsh?

No, that sounds about right and is consistent with the rules. About as harsh as reality... at least I think it sounds realistic (pretty unfamiliar with the actual realities of hearing at a distance and through background noise, but I assume that the hearing rules are at least loosely based on reality).

It's not clear to me though where the short list of background noise penalties (busy street -5, blaring TV -6, fireworks -10) came from, and why those things aren't in the table, listed with dB values and ranges. It would be awfully handy if there was deterministic way to pick any noise of a given dB and determine the penalty it gives to hearing another noise when it's background. For instance, it seems reasonable that a normal conversation would penalize the hearing roll to hear leaves rustling. What noises count as a -1 to -4 background noise penalty, and which fill the gap between -6 and -10? And then beyond?

And I'm also unsure when Parabolic Hearing would be better choice than Acute Hearing, and vice versa, what hearing penalties one can handle and the other can't, and where they overlap (at least, certainly, both will assist in hearing at a distance).