What are some examples in which readers see the negative changes in Charlie Gordon as the story of Flowers for Algernon continues?

In this fascinating novel it is shown that Charlie's
meteoric rise in intelligence is not accompanied necessarily by the maturity, wisdom and
understanding that we would associate with such a ferocious intelligence. One important
pivotal moment is when Charlie goes to Chicago and realises that the doctors that were
responsible for his experiment, and which he looked up to as if they were almost
god-like figures, are actually less intelligent than him. He can't comprehend that
figures that had such power and authority over him before are actually more limited than
he is intellectually, and as a result, he judges them incredibly
harshly:

I
couldn't stay at the party. I slipped away to walk and think this out. Frauds--both of
them. They had pretended to be geniuses. But they were just ordinary men working
blindly, pretending to be able to bring light into the darkness. Why is it that everyone
lies? No one I know is what he appears to
be.

Charlie is thus shown to
be actually very limited, in spite of his massively high IQ, because of his lack of
understanding of himself and others. It is this event of course that leads to his escape
with Algernon.