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Young woman with amnesia unable to hold a single face in short-term memory… unless it’s Paris Hilton!

The headline above is not mine: it’s from the press release about this story. Turns out, as far as I can tell, it’s not just Paris Hilton, but any familiar face. Just as well: only being able to remember Paris Hilton sounds like a fate worse than death.
Here’s the press release, from Baycrest*:  http://news.baycrest.org/2011/11/young-woman-with-amnesia-unable-to-hold.html, and the original (not-yet-in-print) journal article:  http://www.sciencedirect.com/science/article/pii/S0028393211004817 (or at least the abstract: I can’t find an institutional access link – just ‘purchase PDF’ for the whole article. Maybe it’ll be more available once it’s appeared in the journal).
The press release, including a one-minute video of Nathan Rose. the lead researcher, talking about the case: (posted below: also visible at http://www.youtube.com/watch?&v=3a-NBUNve-4) gives quite a lot of information and explanation. Worth looking at the press release before reading the rest of this post, maybe.

I think there are two things interesting about this: one is that it seems to give new insight into hippocampus damage and how it relates to ‘short term memory’, ‘long term memory’ and ‘working memory’ (and maybe how those are unhelpful/inaccurate ways of describing what people do: certainly the labels are used a bit loosely in the article).

The other thing I think is interesting, though, is mentioned almost in passing in the release:

Despite HC’s severe memory impairment – the result of experiencing hypoxia (loss of oxygen) in the first week of life – she is a relatively normal functioning individual and college graduate, who is an avid film buff and celebrity watcher.

She’s described as having ” a profound long-term memory deficit” (about 40 seconds into the video). I guess that means the common amnesia problem of transferring immediate memory into something that is accessible over longer periods. But she also has “relatively preserved semantic memory” (from the journal article abstract). Her brain damage is described as:

This woman is missing 50 percent of the normal volume of her hippocampus with no obvious damage to other parts of her brain. This provides an extraordinary opportunity to generate new insights about how this crucial memory centre of the brain affects both short-term and long-term memory,” said lead investigator Nathan Rose, a post-doctoral fellow in Cognitive Neuroscience at Baycrest’s Rotman Research Institute.

Right: so she’s had a severe problem from just after birth, but has developed a “relatively preserved semantic memory”, and is normally functioning and a college graduate. OK, ‘relatively preserved’ could mean relative to her severe deficit in other areas, and still be quite poor, but if she’s normally functioning and can follow films well enough to enjoy them, she sounds pretty normal. But wouldn’t the standard ‘short-term transfer to long-term’ amnesia deficit mean that she couldn’t really build up any kind of semantic memory? We know that other individuals with anterograde amnesia can accumulate procedural and implicit memories, but the kind of learning/memory required to learn to make sense of the world (and to get a college degree, though making sense of the world is harder, I think) seems to be different from that.
I guess my interpretation is that people can be better at coping than the brain science suggests – and if the damage occurs early enough, there may be ways of getting round it/compensating for it – but also that our categories of STM, LTM, semantic, procedural, explicit, implicit, while very useful for describing, and maybe theorising, memory, are probably crude over-simplifications abut an activity which is much more complex and fluid than these models.

…and: you always need a good headline:
Young woman remembers mum’s face better than strangers’ faces
– which I think is also an accurate reading of the press release (but does admittedly leave out the psychological point) wouldn’t generate much interest. Maybe there’s a positive side to Paris Hilton after all. Maybe.

*“Headquartered on a 22-acre campus in Ontario and fully affiliated with the University of Toronto, Baycrest is the global leader in developing and providing innovations in aging and brain health.” From what I can see on the website, I think it’s a combined hospital, care centre, and research centre.

Understanding narratives, in film and elsewhere, actually requires a lot of cognitive abilitiesOne of the most damaging (for her) early features of my mum’s gradually developing vascular dementia was her inability to follow (and therefore enjoy) stories, films, radio plays. On the other hand, I wasn’t that worried when my son, at about age four, enjoyed watching the video of Star Wars again, and again, and again, and again. This was valuable cognitive development stuff: he was coming to understand about sequences of events, and narrative – and probably about film representation of the real world (well Tatooine, anyway). He grew up to take a Drama degree….

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