#ps -u USER
PID TTY          TIME CMD
20278 ?        00:00:00 screen
20280 pts/5    00:00:00 main
23911 ?        00:00:00 screen
23913 pts/1    00:00:00 bash
24259 pts/1    00:00:00 htop

#ps all -u USER
1  1000 23911     1  20   0  23528  1652 -      Ss   ?          0:00 SCREEN
0  1000 23913 23911  20   0  20876  3624 -      Ss   pts/1      0:00 /bin/bash
4     0 23923 23921  20   0  21004  3920 -      Ss+  pts/4      0:00 -bash
0  1000 24259 23913  20   0  24388  2716 -      S+   pts/1      0:03 htop
0  1001 25450 25449  20   0  21936  4744 -      Ss   pts/3      0:00 -bash
0  1001 26758 26756  20   0 478724 235580 -     Rsl+ pts/2      9:45 /usr/local/bin/rtorrent
1  1000 20278     1  20   0  23536  1728 -      Ss   ?          0:00 SCREEN -fn -dmS rTorrent /usr/local/bin/rtorrent

Show threads:
  H                   as if they where processes