Tuesday, July 8, 2008

I'll make conversation while monitoring for verbal clues


Given my stunning performance on the Cambridge Face Perception Task, the postdoctoral researcher at the Jamaica Plain Veterans Administration who is looking for prosopagnosics was eager for me to come to the lab. We reviewed my experience of face-perception difficulty and he decided to start off by checking some of skills that often accompany face perception difficulties: gender, age and attractiveness identification. This battery, The Philadelphia Face Perception Battery (pdf), also had an upright only face discrimination task (choose which of two choices was most similar to a target face). Surprise: I was normal on all 4 tasks.

The researcher later emailed me:

From the tests you've taken so far, it seems like you have a moderate form of prosopagnosia that is somewhat specific to facial identity. However, there are a couple tests that you were able to "beat", most likely through employing compensatory strategies.

The stategies were simple: I used skin tone, and fat/thin face shape. On the Philadelphia Battery, I only had to look at three faces and make one decision. In contrast, the CFPT is crazy hard, because on a single trial one is confronted with 7 faces: a target and 6 faces that have to be put in order. I now think that my problem with the CFPT was that there were so many faces that I couldn't pick out similar/differnet features. As I scanned across the row of faces, they all looked equally dissimilar to the target. Consistent with prosopagnosia, I showed no inversion effect (as noted in prior post).

My hypothesis is that my face perception abilties are good enough to process three faces at a time, but I break down under conditions of heavy cognitive demand.

Along these lines: I had some problems watching a DVD last night, La Guerre est finie. It was a black&white 1960s movie about anti-Fascist Communist revolutionaries scuttling back and forth between Spain and France, in French with English subtitles. I couldn't keep straight who was the main character vs. one of at least two other white mid-40s males with short black hair wearing a suit and tie. I've had this problem frequently before, but it seemed really acute in this particular movie. To figure out the political machinations I had to at least know who was the undercover agent from Spain vs. his friend in Paris. I just gave up and fortunately after this first half hour got used to his face and voice enough and the friend had receded in importance so only the main character was mostly in view, etc.

This fits the hypothesis of information overload. My face processing is exacerbated by on-going cognitive demands. The movie was black and white, so it was already a difficult person-detection task because of reduced cues for skin color, hair texture, clothing, AND I had to read subtitles so had less time to even look at the characters.

Yes, I'm mostly a single-channel processor. I dislike concurrent processing and turn off TVs, radios when I need to work, I find even a background babble of speech (like a TV in a distant room) annoying because it tugs at my attention (nonspeech is okay).

So... I have mild prosopagnosia compounded by poor concurrent processing, whaddaya think? And remind me of your name when we meet (smile).

10 comments:

Anonymous said...

I'm curious what happened next - only because I've been for the same tests. No doubt with the same researcher.

HumanProject said...

The researcher who tested me sees the next step as a training program. I would take home a laptop and spent 20-30 minutes per day repeatedly doing a face discrimination task which focuses not on the features, but on the distance between the features.

The idea behind this training is that the prosopagnosic is forced to focus on configuration of the whole face. One of my students worked as a research assistant in this lab last year and says that he did the training, and even though he has normal face perception, the training moved him into the superior range on tasks like the Cambridge Face Perception task.

The drawback of the training is: not everyone benefits from the training; and the training is long duration (daily for at least a month). So its a big commitment. I'm worried I would start the training and then get too busy and start missing days, which would screw up their protocol.

Anonymous said...

Interesting - he told me it was only 2-3 weeks, and seemed to think they'd had pretty good success with it so far.

I'm also a little nervous about the time commitment. I'm in a position which often barely allows me enough time or brain cells left to put my pants on in the morning. Curiosity always gets the better of me though, so I'd like to at least attempt it. When I discussed my time constraints with him, he didn't seem to think it was huge deal if I fell out of the study by not completing it. I could be wrong, but I got the impression he's having a tough time getting enough people together.

I also scored poorly on the CFPT, and was normal on the same four initial tests. I also pointed out the skin tone and fat-thin issue, after which I was also given a version of the PFPB where the faces had been made black and white, and he'd cut them out to make them the same shape.

This whole experience has me a little bit on edge. It has no real impact on my life, but there's something unsettling about going from weird to classifiably weird.

HumanProject said...

Dear anonymous,

Why not go ahead and do the VA face training study since the time commitment is actually pretty modest, as you noted (and what you say is probably the correct time, I probably had the study duration wrong due to using my brain cells to put on my pants).

It does seem like the you and I have similar profiles.

But what about this:

"This whole experience has me a little bit on edge. It has no real impact on my life, but there's something unsettling about going from weird to classifiably weird."

Learning one has a diagnosis sometimes brings an element of relief, as in: "I always knew there was something not quite right, and now the experts have confirmed my intuition, so rather than being uncertain, at least I have a label and can take action" etc.

But I also wonder why you feel having prosopagnosia has no impact on your life -- what about not recognizing people and all that?

BTW, go ahead and email me (see Profile) if that is more convenient for you.

Anonymous said...

I did shoot you a email, but since for all I know it got spammed, or was incoherent (I was holding my eyes open as I was writing it), here is the abridged version:

1. I'm sorry if I wasn't clear - I meant that the diagnosis does not affect my life. I know that prosopagnosia has, although I do think the degree is highly arguable.

2. I felt some relief at first, but I've effectively been told:
that a) I've been screwed up my whole life, b) I have a "disorder," which is a label I'm not excited about, and c) there's no cure.

3. There is no three, I just didn't think I could have a list with only two items.

Anonymous said...

Did you ever have head trauma?

HumanProject said...

Dear Anonymous,

I was in a serious motor vehicle accident at age 12 and spent 3 months in the hospital with multiple fractures; but a bed-side neurological exam in the days immediately afterward led to the conclusion of no neurological problems. It was 1975 and no brain scan or head x-ray was conducted.

About 5 years ago I had a long talk with my mother about whether I could have suffered brain injury during the 1975 accident that affected my personality in subtle ways; she maintains she never saw any post-accident difference. I definitely have some personal eccentricities but I've just had to accept these as my personality. The eccentricities are things like: I'm hyper-rational, a bit literal minded, don't feel much need to conform to social rules that don't make sense to me, crave intellectual stimulation, not good at social chit-chat, low tolerance for being bored, novelty-oriented, etc. These sound like normal personality variation, not head injury.

Its true that I don't remember being bad at face recognition as a child; my first strong anecdote of not recognizing someone is an incident at 17.

I've been thinking about writing a blog entry about the 1975 accident because I'm a biker and the old accident was a biking accident but I have amnesia for the accident itself and most of two weeks following the accident

But could closed-head injury cause the mild prosopagnosia I have? Although I'm a university professor and researchers in my dept do fMRI research I have never had a scan myself.

What do you think?

Dan said...

And now for the bright side of prosopagnosia: you'll never turn to god because you saw Jesus on a slice of toast.

HumanProject said...

Dan,
Ha ha, thanks for the chuckle.

Since I am an atheist, the pattern-making centers of my brain aren't drawn to images of that particular folk hero.

But keep the prosopagnosia humor coming! There must be a website on this somewhere.... SNL should do a skit; like the old Pat routine.

Anonymous said...

Very interesting. Closed head trauma is a notable cause of prosopagnosia, perhaps the most common. The very subtle personality traits you describe are also seen after CHI, and can extend to other areas as well...
A plain CT would show if there was some damaage- but what to do with such knowledge? You are clearly happy and bright.