Today, I believe I have discovered something rather significant about myself and resolved a linguistic occurrence in my perceptions that has confused and slightly bugged me for years.
Specifically, I cannot differentiate voicing in plosives: I cannot tell the difference between the b and p sounds, between the d and t sounds, and between the g and k sounds without context.
Over the years, several occurrences in speech have been weird for me, particularly in confusion when someone introduces a new initialism to me. The most recent occurrence is SIPB meetings near the start of the past year. Specifically, one particular new member who has a username that starts with “bp” (who, incidentally, if you read this blog, you have a fairly high chance of knowing), when saying his username, sounded to me like the first two letters were the same, which often made me pause for a moment because I remember what his username was written down, and double-letters are a salient feature in my recognition of strings. (“SIPB” itself was not a problem for me when first introduced, because it’s pronounced with the first three letters together as one syllable, then one syllable dedicated for the last letter.) After finally deciding to research this a bit and listen to some audio samples of speech comparatively to figure out what’s going on, I have come to the conclusion that I actually simply cannot distinguish these pairs of sounds, and specifically that when they’re used in words, I mentally fill in which letter is used based on which one the context deems appropriate.
I decided to go chart out how many sounds I can distinguish. Here are charts where I grouped sounds I cannot distinguish from each other together, so that by counting the number of groups, I know the number of distinct phonemes I can recognize. I decided to only separate groups for which I can consistently tell their members apart; that is, almost always categorize correctly, not just significantly better than 50-50.
(Note that in the consonants chart there were a few consonants that were really rare that I just plain gave up on. Also, there’s a few laryngeal consonants that, despite understanding some of their places in speech, I cannot distinguish from silence and thus I did not assign to any group.)
Counting up the groups, I can distinguish 32 different consonants and 13 different vowels. In addition to these, I can distinguish 5 clicks, and 5 aspirated versions of phones, for a total of 55 distinct phonemes.