What mental abilities did you not know it was possible to lack?

Examples:

I was floored to learn that my wife, who is a thoughtful, intelligent, academically successful person, has no ability to visualize images in her head. When she closes her eyes, she always sees black and that’s it.

On the other hand, she posses true multitasking ability, which I did not realize existed. I had always assumed people who claimed to multitask we’re just switching between tasks every few seconds, but she can honest-to-God do two things (like watch TV and browse te web) at the exact same time and pay attention to both.

One of my nephews was severely abused in unspeakably ghastly ways and came out with brain damage. He is fundamentally incapable of grasping the concept that his behaviors affect how others treat him. Spank him for smashing a glass intentionally? He is sure You’re just being mean at that moment, so his behavior won’t change. Reward him for the (rare) good behavior? He thinks you’re just being nice at that moment, so that behavior will not be reinforced. It’s only a matter of time before he’s institutionalize since its very very difficult to take care of him, but that’s a story for another day.

Lack of knowledge of direction, as in north, south, etc.

Mrs. FtG is completely clueless in this regard. And I’m not talking about just driving in a strange area. At home, she has no idea what direction east is. She doesn’t even know what side of the house gets the morning sun. And we’ve lived here decades.

Once I get her to understand which way is east, she still doesn’t know which way is north. And then she’ll forget it all completely and won’t remember it the next time it comes up.

When I give her driving directions, I can’t say “turn north”, I have to say “turn right”, of course. But she can’t even understand how someone (like me) automatically knows where north is and prefers directions using the cardinal points.

Does echolocation count? I never knew humans could do it. I knew some people could get around fine with their ears but some can actually echolocate, they use clicking sounds and do it whilst they’re cycling or skate boarding, and you probably wouldn’t even know they were blind.

What?

Oh boy. In the upper midwest, where I’m from, lack of direction immediately marks you out as The Other. You can’t even hesitate when telling someone what side of your house that big maple is that needs surgery. They’ll know after half a second that you’re Different.

I’m not very good at visualizing things either. Not completely horrible, but pretty bad. Is your wife bad at recognizing people by sight? I am. I’m not great at fashion and design either.

She’s great at recognizing people by sight, and she has a very wide visual field. When I drive, I have to take my eyes off the road for an instant to read any signs but she can read them from her peripheral vision while focused on the car in frot of her, which I didn’t know was possible.

She has a good sense of fashion and design so she knows what’s good, but she’s eccentric so she’s not afraid to flout those rules and occasionally wear t-shirts or whatever.

Incidentally, I looked it up and about 3% of people have zero mental visualization ability like my wife, but it sounds like you do have a little bit. That is, not complete blackness.

Thanks for pointing out an example of a mental ability you didn’t know it was possible to have. I worded my title too negatively; both sides are perfectly acceptable.

If you’re referring to Human Echolocation, here’s one example. I’d never heard (giggle) of such a thing until I saw this. I hope the video isn’t a hoax.

http://www.wimp.com/seeingwithout/

I don’t mean her actual eyesight, but I think I’m not very good at it because I have a hard time keeping a mental picture of what the person looks like, if I haven’t seen them a lot of times. I hate it because it can be embarrassing when I should recognize someone and don’t.

I don’t have a problem recognizing what looks good or not, but I’m not very good at creating my own unique things because it’s hard to really visualize what the finished creation will look like.

NM

I thought it was something they made up for the Daredevil comics but apparently it is actually possible.

There’s apparently an aboriginal language that has no words for left, right, front, back, etc. You always have to use the words meaning north, south, east and west. Unless you know where you’re facing in relation to the cardinal points at all times, you can’t even give directions to the bathroom.

Hang on…

OK, here is a New York Times article that mentions it, it’s called Guugu Yimithirr:

(Interestingly, its other claim to fame, according to Wiki, is that it’s the source of the word “kangaroo”.)

How do we know they just don’t have words for north south east west and say left right in front behind instead?

The first group of directions is absolute, and the second is relative.

re echolocation, I discovered this independently, some years ago, when I was working in a big warehouse…and the lights went out. I really could get around by snapping my fingers and listening to the echoes.

I’ve met two sociopaths in my life, people who have no ability to demonstrate compassion or even understanding. I’ve also met a few autistic people, who, at least, are much more benign in their behavior. And I guess The Straight Dope has never had a shortage of people who lack the faculty for critical reasoning. (They usually end up pitted…)

Such things probably lie along spectra. Some people are “poor at cardinal directions.” Others are really, really bad at them, and a few are totally blind to them. Where does a personality quirk become a true disability?

(Depends on how many points you get for them, I guess…)

When it causes problems.

I think spanking a kid who has been severely abused could itself demonstrate a lack of a certain mental ability.

I’m always amazed by adults who seem to be unaware of elemental physical laws that most of us become aware of instinctively as children, like what will happen if you ride a bicycle off the tailgate of a pickup truck, or in what direction you will bounce if you jump onto a trampoline from a neighboring roof. Do these people also walk into things a lot, or fall off curbs or out of bed?

Yup. I know someone who does stuff like that all the damn time. I’ve also watched said person take a stubborn tab top off full a bottle of milk, while holding the bottle horizontal for a better grip…

It isn’t possible. She is moving her eyes to see the signs too. She maybe good at doing it very quickly, so her concentration on the road is not impaired significantly, and she may not be aware of moving her eyes, but she is doing so nonetheless. I can assure you that if your wife were to wear eye tracking apparatus while driving, these movements would be clearly revealed.

People’s visual fields do not vary very much (unless they have glaucoma or some other fairly serious eye disease, that restricts it), and no-one can see significant amounts of detail or color in peripheral vision (although we are quite good at detecting movement there). There are just not enough receptor cells out in the periphery of the retina. We all have to move our eyes to see things clearly.

People make saccadic eye movements (rapid jumps or flicks) about three times every second, on average, in order to bring stimuli of interest into focus at the fovea, the center of the retina where we do have detail and color vision. We are unconscious of of making the vast majority of them. (There are also several other types of eye movement, some of which are comparably frequent, and which are also mostly unconsciously made.)