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Variants · VR

The virtual water maze (VR)

The same idea, built for people: find the hidden platform in a virtual pool.

Virtual water mazes put a person in a virtual pool and room, and ask them to find a hidden platform using cues around them. Astur and colleagues described one in 1998 and used it to look at sex differences in human spatial navigation.

VR participant safety

Clear safety steps protect participants and keep sessions calm, which also helps them engage with the task.

More detail

Participants should not drive or operate machinery straight after VR, should hold the frame with both hands, and a supervisor should be present; treadmill shoes are for carpet only and gate clips must be locked.

Presence and cybersickness are negatively related (Weech et al., 2019), so a comfortable, well-fitted set-up supports both participant welfare and data quality.

VR water maze in eight steps

Plan safety, set up the treadmill and headset, edit your vrScript, run it with its function key, then analyse just like the water maze.

  1. Put your own safety procedures in place and advise participants not to drive or operate machinery straight after VR until they have readjusted.
  2. Assemble the treadmill or treadplate first, exactly where it will be for trials; on the treadmill both closure-gate clips must be locked when a participant is in VR.
  3. With the participant standing where they will be, set the headset boundary and recentre the view.
  4. Connect the headset with the Link cable (Air Link off), then use the HVS Control Panel buttons in order: the Link app button, then ‘Prepare to Enable Link’, wait 30 seconds, then ‘Start SteamVR’.
  5. Open your vrScript files in a text editor such as Notepad++; set SET_SCENE, TRACKING_DIAMETER 200 (recommended), the start points, TARGET_RADIUS and TARGET_POSITION, then save.
  6. Click ‘Run HVS 6D VR’ and press the function key for your experiment (e.g. F1 for F1.vrScript).
  7. Let the participant practise in the pre-trial location, ask them to stop moving, then press Enter to start the trial.
  8. Click ‘Morris Water Maze’, then ‘ANALYZE’: double-click a trial for its plot, or make a SUM and a CST file just as for the water maze.
More detail

If a trial is disrupted, press Escape, then Enter to re-run the same trial (the original is saved as far as it got). Use one navigation mode for all participants in an experiment.

Keep and back up your .BOND and .hvs files, and your .sum files, even after exporting results; the vrScript files and .BOND headers are the best configuration record for methods sections.

Having trouble with a headset, a treadmill or SteamVR? The VR hardware page shows what the 89 hardware questions cover and where to find the answers.

HVS Image describes its virtual reality Morris water maze and other behavioural neuroscience tasks in virtual reality.

Sources

  1. Astur et al. (1998). A characterization of performance by men and women in a virtual Morris water task: a large and reliable sex difference. Behavioural Brain Research 93(1-2):185-190. doi:10.1016/s0166-4328(98)00019-9
  2. Astur et al. (2002). Humans with hippocampus damage display severe spatial memory impairments in a virtual Morris water task. Behavioural Brain Research 132(1):77-84. doi:10.1016/s0166-4328(01)00399-0