JetBall-Dome

JetBall Dome

Virtual Reality (VR) can be used for mice to investigate brain functions during decision making. The JetBall-Dome is a worldwide unique product with a Dome for mirror projection of a virtual environment and a spherical treadmill with optional operant devices. The JetBall, an air-cushioned spherical treadmill allows a restrained animal to navigate in a virtual environment. The animal can be examined with electrophysiological, imaging and optogenetic methods while it performs behavioural tasks employing navigation, cognition, learning and memory.

  • A quarter-sphere mirror reflects the warped image from a projector onto a spherical dome screen
  • Larger surface for presenting virtual reality
  • Seamless display
  • Predefined experiments or create your own ones with our software
  • Data transfer system to combine JetBall data with external data.

Examples of neural dynamics during navigation and decision making in, e.g., a Corridor or T-Maze:

  • Intracellular dynamics and population activity of hippocampal place cells
  • Grid cell firing fields in virtual environments
  • Neocortical neural coding during decisions.

“Our experiments provide, to the best of our knowledge, the first direct intracellular recordings of membrane potential in MEC neurons of navigating mice. By measuring subthreshold membrane potential, these recordings reveal how synaptic input interacts with the intrinsic properties of stellate cells to drive grid-like firing during spatial navigation.”

Schmidt-Hieber C. & Häuser M. 2013. Cellular mechanisms of spatial navigation in the medial entorhinal cortex. Nat Neurosci. 16, 3: 325-331

We thank Dr. Christoph Schmidt-Hieber for supporting the development of our dome sphere that is based on his original designs.

Power
Power input voltage 100-240 V AC
Power consumption 920 W (maximal)
Dome sphere
Diameter 120 cm
JetBall Spherical Treadmill with Stand, 20cm for Mice
Ball Holder material Aluminium
Ball diameter 20 cm
Ball material Polyvinyl chloride
Pressure Regulation
Flow meter Range: 4-50 l/min, for experiments: 25 l/min
Pressure regulator 6.9 bar (maximal), for experiments: 2 bar
Sound pressure level 48-52 dBA (top of the ball, 1 cm distance from the ball, air flow 20 l/min)
Projector
Resolution WXGA 1280 x 800
Light output 3000 or 3100 lumens
Contrast ratio 2000:1 or 3000:1
XY-Motion-Sensor
Resolution 200-5700 dpi
Max. speed Up to 4.19 m/s
Liquid Reward System
Peristaltic pump, typical flow rate 0.45 ml/min
Lick sensor, material (outer cover) Polyvinyl chloride
Movable Rack
Width 59.5 cm
Depth 62.0 cm
Height (without control monitor) 98.5 cm
CategoryOptionDescriptionIn Basic Package included
JetBall Basic Package
  • For mice, 20cm spherical treadmill

120cm dome with stand, projector, spherical mirror, spherical treadmill with stand (Ball Holder, two balls), Dual XY-Motion Sensor, movable rack, computer (pre-installed: PhenoSoft Control, PhenoSoft Schedule, PhenoSoft VR, Virtual Corridor 2 m), control monitor, keyboard, computer mouse, power supply unit, pressure regulator system
(compressor is not included).

Virtual Mazes
  • Endless Corridor
  • T-Maze
  • Y-Maze
  • Plus-Maze
  • Open Field 1m

Each maze is available with mode for free or linear run.

Ball Holder
  • Ball Holder System 20cm, for mice

Basic package includes one Ball Holder.
Also useable as a stand-alone product without a virtual reality system.

Extra Ball Holder
  • Ball Holder System 20cm, for mice

For training.
Also available as a stand-alone product without a virtual reality system.

Ball
  • Ball 20 cm

Basic package includes two balls.

Extra Ball
  • Ball 20 cm
Positive Reward
  • Liquid Reward System, 20cm

Retractable: position is adjustable, servo-driven.
Lick Sensor: a drop of water is only delivered when the animal licks.

Negative Reward
  • Air Puff System, 20cm

Frontally directed tube; moved with retractable reward system.

Whisker Stimulation
  • Whisker Stimulation System, 20cm

Air flow when animal approaches virtual walls.
Twin system for left and right whiskers, position adjustable.

Brakes
  • Brake System, 20cm

To stop the spherical treadmill, e.g., at the end of a virtual corridor or after a wrong decision in a Y-maze.

Acoustic
  • Acoustic System

E.g. to use a sound as a landmark.

Odour
  • Olfactometer

E.g. to combine an odour with a virtual landmark.

Body fixation
  • Head Holder with stand for mice with 4 bars.

For optogenetics, imaging or electrophysiology.

JetBall-Dome

Inside view of VR projection dome with JetBall and corridor maze.

Overview of the JetBall-Dome

Stand with a dome, projector, quarter-sphere mirror and the spherical treadmill (Ball Holder made from one solid block of aluminium with stand and polystyrene ball)

Navigating mouse in a virtual corridor.

Control Unit with movable rack

  • Control monitor
  • Keyboard and computer mouse
  • Pressure regulator system with
  • flow meter and pressure regulator (second pressure regulator for air puff/whisker stimulation)
  • Computer
  • Power supply unit.

JetBall Spherical treadmill

Aluminium Ball Holder with polystyrene ball and the various operant modules (view from the top). The modules are highlighted in the following pictures.

Liquid Reward System

Mounted on the retractable operant device of the Ball Holder and lick sensor.

Air Puff System

Mounted on the retractable operant device of the Ball Holder. It consists of a metal tube connected by plastic tubing to a valve. The valve is connected to a flow meter, pressure regulator and the compressed air system.

Brake System

Consisting of two lateral and a frontal servo-driven brake.

Whisker Stimulation

Consisting of two metal tubes mounted on articulated arms that are attached to the Ball Holder. Plastic tubing connects the tubes to the valves of the compressed air system.

Dual XY-Motion Sensor

There are two sensors measuring the movement of the polystyrene ball.

Body Fixation

Ball Holder (view from the side) with head holder for fixing the mouse (on the right side).

PhenoSoft Control – Unser Interface

Basic software for all products by PhenoSys. Control of hardware components.

PheoSoft Control – Log File

The log file containing the experimental data is written in a CSV format and is automatically saved.

PhenoSoft Schedule

Experimental schedules are defined with the help of state diagrams by using predefined activities from PhenoSoft.