I've seen my file so I know my therapist takes notes at some point, but definitely not during the session.

I did have a therapist who took notes during the session once and it was totally distracting - it was like anytime I said anything with any kind of emotional power he'd stop the session to write it down, and I was left hanging there. He wasn't a very good therapist for me. I needed his full attention way more than I needed him to remember any of the particular details of my emotions.