Auditory Processing Disorder (APD or CAPD) affects the way my brain processes auditory information. I do not process the information I hear in the same way as others do, which leads to difficulties in me recognizing and interpreting sounds, especially the sounds composing speech. 

In layman's terms, what does that mean?

I hear perfectly (no hearing loss whatsoever in either ear) and my brain works brilliantly, however, I have intermittent "short circuits in the wiring" between my ears and brain on the left side. Essentially, the message that reaches my brain is not necessarily that same message that I heard.

I have an intermittent inability to process verbal information, leading me to guess to fill in the processing gaps. I also have significant problems decoding speech in loud, noisy environments.

I like to say say that there is a gremlin hanging out in the wiring between my ears and my brain and he randomly flips a switch for fun just to piss me off. When the switch is in the up position, I process fine. When it's in the down position, you might as well be speaking ancient Egyptian.

Examples:

1 - I may confuse sounds such as "hat" with "bat."

2 - I may confuse sounds such as "grunts" with "runs."

3 - I may confuse "the train made it to the stop on time" with a nonsensical "the plane made it to the shop in time."

Even more frustrating is that when the correct message DOES manage to make it to my brain, the meaning of the message may instead be lost.

Example:

You may say "Jeff, your hair is on fire!" Now, a normal response would be "Holy crap, put out the fire!" My response, may simply be a blank stare. I will be able to repeat, word for word, what you just said, but the meaning of the message will have been lost. Didn't process at all. No need to shout. Increased volume has no effect. I simply did not process what you just said to me. 

Furthermore, there are times that I don't even realize I misunderstood or didn't process what you just said. I, like many with Auditory Processing Disorder, am accustomed to guessing or filling in the blanks when my wiring temporarily goes haywire. My brain will work overtime to make the most sense of what I thought you just said and, and rather than embarrass myself and ask you to repeat what you just said, I'll give you a response to a question you probably didn't ask or just nod my head and agree with you without saying a word (if I am totally lost).

Example:

You may say "Jeff, how about we go to the beach off the highway at around 3 o'clock today." 

What I'll hear is "Jeff, _ow about _e go to the _each __f the _i__way at around 3 o'clock today."

The "_" represent syllables that I could not distinguish or background noise simply drowned them out. Sometimes I can fill in the blanks perfectly based on visual context, lip reading or knowledge of the person, other times the sentence is so messed up I cannot. The response I give you will clue you in on what I did or did not process.

The best APD analogy I can think of is like having poor mobile phone reception, where the signal gets intermittent static, background noises get in the way, or the call gets dropped. Perceiving and decoding what people are saying, or separating a meaningful message from non-essential static or background noise is sometimes futile. Certain words may be drowned out by other sounds, some words may sound like different words or the entire message may come thru as a completely meaningless string of absolute garbage.