Weird experiences: aphasia (a collection of examples)
Aphasia is a wide range of language impediments caused by brain damage – usually a stroke. Those impediments can be very specific – for instance, a person might be able to say “walk” as a noun but not as a verb.
The Man Who Lost His Language
From Sheila Hale’s The Man Who Lost His Language (available on LibGen).
Unable to recall certain classes of words
Some aphasics who can’t speak can sing the words of familiar songs. Proper names are difficult for some aphasics – as, indeed, they are for some normal people. Guy Wint was at first unable to recall the names of the friends who visited him in hospital. But he could remember their telephone numbers, and so would report to his wife that Sloane 2381 had been to see him, or the flowers had been brought by Mayfair 9643.
Some have difficulty with other classes of nouns, colours for example. There are aphasics who can demonstrate that they experience colours normally; they can match different hues or put the correct colour on a black-and-white photograph of, say, a banana or grass. But they have problems naming or understanding the names of colours, and will frequently, for example, identify ‘blue’ as ‘green’.
 G. Wint, The Third Killer, 1965.
 A. R. Damasio and H. Damasio, ‘Brain and language’, Scientific American, Sept. 1992.
Unable to pronounce familiar words
Some aphasics are disproportionately impaired for long, unusual words, others for the shortest and most familiar words, such as and, the, was, in. A recovered Swiss aphasic described in his memoirs having had more difficulty pronouncing the French for if and since than Nebuchadnezzar and Popocatepetl.
 Gardner, The Shattered Mind
Can speak verbs but not nouns, even when the word is the same
Some have more trouble with verbs than with nouns and vice versa. Some can speak nouns but not verbs, but when reading aloud it is the other way round. There are aphasics who can say or read aloud certain words, such as park, walk, play, as nouns but not the same words in their verb form, or vice versa. A case has been reported of a man who can say the plural noun cuts but cannot say, read aloud or even repeat the final -s of the third person singular of the verb ‘to cut’.
 S. Chiat and E. V. Jones, ‘Processing language breakdown’, in M. J. Ball (ed.), Theoretical Linguistics and Disordered Language, 1988
Can read the names of musical notes in the key of G but not in the key of F
It seems that all languages can be impaired by damage to the language centres, even those that rely on right-hemisphere specialities like tone or the analysis of visual input. Any system of communication that consists of discrete arbitrary symbols ordered according to abstract rules is vulnerable: tone languages like Chinese, deaf and dumb sign languages, even musical notation.
Performing musicians and composers may lose the ability to read or write music but still be able to play and sing from memory. An Italian-based team of researchers recently reported the case of an aphasic professional organist who could read the names of musical notes in the key of G but not in the key of F, although she could recognize both keys when she heard them and could play in both on the piano at sight.
 Schön, D., Semenza, C., & Denes, G. (2001). Naming of Musical Notes: A Selective Deficit in One Musical Clef. The quote is not precise – the actual paper says “The deficit on which we focused was her inability to read orally the bass (F) clef, often substituting it with the violin (G) clef.”
Bilingual people can forget one language while retaining the other
In bilingual or polylingual people different languages may be affected in different ways. There are bilingual German Jews, who have refused to speak German since childhood, only to find either that they have mercifully lost it altogether or that they are unable to communicate except in German.
The Language Instinct
From Steven Pinker’s The Language Instinct (available on LibGen).
An internal account of how a stroke feels
One of these victims, who eventually recovered his language ability, recalls the event, which he experienced with complete lucidity:
When I woke up I had a bit of a headache and thought I must have been sleeping with my right arm under me because it felt all pins-and-needly and numb and I couldn’t make it do what I wanted. I got out of bed but I couldn’t stand; as a matter of fact I actually fell on the floor because my right leg was too weak to take my weight. I called out to my wife in the next room and no sound came — I couldn’t speak. ... I was astonished, horrified. I couldn’t believe that this was happening to me and I began to feel bewildered and frightened and then I suddenly realized that I must have had a stroke. In a way this rationalization made me feel somewhat relieved but not for long because I had always thought that the effects of a stroke were permanent in every case. ... I found I could speak a little but even to me the words seemed wrong and not what I meant to say.
An example of speech of a person who can not remember nouns
The neuropsychologist Kathleen Baynes describes “HW,” a business executive who suffered a stroke in this general area. He is highly intelligent, articulate, and conversationally adept but finds it virtually impossible to retrieve nouns from his mental dictionary, though he can understand them. Here is how he responded when Baynes asked him to describe a picture of a boy falling from a stool as he reaches into a jar on a shelf and hands a cookie to his sister:
First of all this is falling down, just about, and is gonna fall down and they’re both getting something to eat ... but the trouble is this is gonna let go and they’re both gonna fall down ... I can’t see well enough but I believe that either she or will have some food that’s not good for you and she’s to get some for her, too ... and that you get it there because they shouldn’t go up there and get it unless you tell them that they could have it. And so this is falling down and for sure there’s one they’re going to have for food and, and this didn’t come out right, the, uh, the stuff that’s uh, good for, it’s not good for you but it, but you love, um mum mum [smacks lips] ... and that so they’ve ... see that, I can’t see whether it’s in there or not ... I think she’s saying, I want two or three, I want one, I think, I think so, and so, so she’s gonna get this one for sure it’s gonna fall down there or whatever, she’s gonna get that one and, and there, he’s gonna get one himself or more, it all depends with this when they fall down ... and when it falls down there’s no problem, all they got to do is fix it and go right back up and get some more.
More examples of forgetting only certain classes of words
The mental thesaurus, in particular, is sometimes torn into pieces with clean edges. Among anomic patients (those who have trouble using nouns), different patients have problems with different kinds of nouns. Some can use concrete nouns but not abstract nouns. Some can use abstract nouns but not concrete nouns. Some can use nouns for nonliving things but have trouble with nouns for living things; others can use nouns for living things but have trouble with nouns for nonliving things. Some can name animals and vegetables but not foods, body parts, clothing, vehicles, or furniture. There are patients who have trouble with nouns for anything but animals, patients who cannot name body parts, patients who cannot name objects typically found indoors, patients who cannot name colors, and patients who have trouble with proper names. One patient could not name fruits or vegetables: he could name an abacus and a sphinx but not an apple or a peach.