/usr/share/ is in octave-psychtoolbox-3 3.0.12.20160126.dfsg1-1ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/octave/
/usr/share/octave/site/
/usr/share/octave/site/m/
/usr/share/lintian/
/usr/share/lintian/overrides/
/usr/share/lintian/overrides/octave-psychtoolbox-3
/usr/share/doc/
/usr/share/doc/octave-psychtoolbox-3/
/usr/share/doc/octave-psychtoolbox-3/copyright
/usr/share/psychtoolbox-3/
/usr/share/psychtoolbox-3/PsychHardware/
/usr/share/psychtoolbox-3/PsychHardware/iViewXToolbox/
/usr/share/psychtoolbox-3/PsychHardware/iViewXToolbox/tcp_udp_ip/
/usr/share/psychtoolbox-3/PsychBasic/
/usr/share/octave/site/m/psychtoolbox-3
/usr/share/doc/octave-psychtoolbox-3/changelog.Debian.gz
/usr/share/psychtoolbox-3/PsychHardware/iViewXToolbox/tcp_udp_ip/pnet.mex
/usr/share/psychtoolbox-3/PsychHardware/PsychHID.mex
/usr/share/psychtoolbox-3/PsychBasic/PsychKinectCore.mex
/usr/share/psychtoolbox-3/PsychBasic/Screen.mex
/usr/share/psychtoolbox-3/PsychBasic/WaitSecs.mex
/usr/share/psychtoolbox-3/PsychBasic/IOPort.mex
/usr/share/psychtoolbox-3/PsychBasic/moglcore.mex
/usr/share/psychtoolbox-3/PsychBasic/moalcore.mex
/usr/share/psychtoolbox-3/PsychBasic/GetSecs.mex
/usr/share/psychtoolbox-3/PsychBasic/PsychPortAudio.mex