Present participle and past participle adjectives can be confusing. Present participles are verbs ending in -ing that are used as adjectives. Past participles are the forms used with the perfect tenses. With regular verbs, they are formed by adding -ed, but with irregular verbs, the past participles are the ones like known, gone, taught.
The boring book put me to sleep in record time.
The bored reader fell asleep very quickly.
One way that the difference between the meaning of the two participles is explained is that the present participle describes something happening or a quality. In our sentence above, the quality of the book for the reader is that it is boring. This is contrasted with the past participle which is supposed to show that something has happened. While this explanation works somewhat for the present participle, it doesn't work for me with the past participle. So it seems like this explanation works when the participles are used as verbs.
This explanation is not very satisfactory for the participles when they work as adjectives. It fails to explain to me the meaning of bored reader. Instead, I think that boring is the quality that the book gives to others. In contrast, the past participle describes the feeling of the person.
In other words, present participle adjectives are used to describe feelings or reactions that other people have of the subject or the noun modified. Past participle adjectives describe the feelings of the subject.
The book is boring. (This is the feeling of the reader.)
Now we can't say in English, except in literary terms, that the book is bored. Books do not have feelings.
The bored reader fell asleep very quickly. (This is the feeling of the reader.)
The boring book put me to sleep in record time. (This reader has these reactions or feelings about the book.)
So if I say that
I am confusing.
I am describing the reactions of other people to me.
If I say that
I am confused.
I am describing my feelings about something.