/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/ is in psychtoolbox-3-common 3.0.11.20131230.dfsg1-1build1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/60-vpixx-permissions.rules
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/Contents.m
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/DatapixxBasic/
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/DatapixxBasic/Contents.m
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/DatapixxBasic/Datapixx.m
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/DatapixxBasic/DatapixxAudioKey.m
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/DatapixxBasic/DatapixxInfo.m
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/DatapixxBasic/PsychDataPixx.m
/usr/share/psychtoolbox-3/PsychHardware/DatapixxToolbox/DatapixxBasic/ResponsePixx.m