Logo Utrecht University

UiL OTS Labs

Facilities

EEG lab

The EEG lab (room K.13) allows for conducting EEG experiments. The lab provides EEG equipment in the test room, and a stimulus PC and a data acquisition PC in the control room.

Relevant how-tos

Relevant how-tos are linked here.

Technical specs

Test room

  • Approx. 10 m2 with a window allowing daylight to come in
  • A pan-tilt-zoom camera allows capturing the participant’s activity in the room
  • Table for debriefing the participant
  • Participant desk and adjustable chair (up/down)
  • Sink to wash electrodes

Biosemi Analog-To-Digital (AD) boxes


  • For recording cortical responses or electroencephalography (EEG)
  • serial: ADC 16-11-803
  • Compatible with pin or flat-type active electrodes
    • ‘Active electrodes’ entails that signal amplification occurs very near the recording site (minimal inference)
  • Amplification is via direct current coupling (DC coupling)
  • Both type of electrodes have a build-in high-pass filter (this is needed to prevent aliasing)
    • fifth-order filter that is -3 dB at 1/5th of sample-rate (e.g. 3.3kHz at 16kHz sample rate or speedmode 7/9)
  • LSB for standard electrodes is 31.25 nV (1/32th microvolt)

Graph shows the signal diminishing. One equals the dynamic sample rate (e.g. 16 kHz). Taken from the Biosemi website.

Graph shows the signal diminishing. One equals the dynamic sample rate (e.g. 16 kHz). Taken from the Biosemi website.

Graph shows the signal diminishing. One equals the dynamic sample rate (e.g. 16 kHz). Taken from the Biosemi website.

Graph shows the signal diminishing. One equals the dynamic sample rate (e.g. 16 kHz). Taken from the Biosemi website.

  • Special for recording auditory-brainstem Responses (ABR) or frequency-following response (FFR)
  • serial: ADC 17-14-1114
  • Amplification is via alternating-current coupling (AC coupling; still uses the battery)
    • From the Biosemi website: “In the ABR setup, the difference between a pair of electrodes is digitized after (high gain) AC amplification, whereas with the standard electrodes the voltage with respect to CMS is digitized after (low gain) DC amplification (and the difference between channels is calculated in software).
  • Needs to be operated in speedmode 9 (ABR mode)
  • Requires the use of special flat-type active electrodes that have less noise but have–in addition the the low pass mentioned earlier–
    • This filter is an high-pass filter in the electrode amp stage (first-order filter which is -3 dB at 100 Hz)
    • AC input range 8 mV peak-to-peak (AC amplification)
    • DC input range ± 250 millivolt
    • noise over the the full bandwidth less than 4 microvolt peak-to-peak
  • CMRR > 150 dB
  • LSB for ABR electrodes is 488 pV (1/2048th microvolt)

 


AD-box switch
Sample-rate
Pin channels + EX channels + Sensor channels
0
Daisy-chain mode:In speedmode 0 to 3, the AD-boxes work as up to 4 optical fiber ‘daisy chained’ boxes, each with a maximum of 128+8 channels+sensors @ 2 kHz, speedmode switch = box number. (0=Box1, 1=Box2, 2=Box3, 3=Box4). Daisy chain mode requires an extra fiber input to be installed on the front of the AD-box. (Not done at the UiL-OTS lab. equipment)
1
2
3
4
2048 (2 kHz)
256+8+7
5
4096 (4 kHz)
128+8+7
6
8192 (8 kHz)
64+8+7
7
16384 (16 kHz)
32+8+7
8 (AIB-mode)
2048 (2 kHz)
256+8+7+32AIB
9 (ABR-mode)
16384 (16 kHz)
5


BioSemi equipment

  • Two 64-channel electrode sets: C1+2, and D1+2. (we used to have A1+2 and B1+2 but those are now broken beyond repair – if we really have only two sets now, we will need to order a third set)
  • Three 32-channel electrode sets: E, F and G. Bundle E is under investigation at BioSemi.
  • Galvanic Skin Response module (GSR)
  • Respiration belt. Nihon Kohden TR-753T.
  • Headcaps overview
  • Biosemi manual for handling the electrodes

History/status of EEG bundles

ID           Lab ID         Status
====================================================
FR14-004527  Set C1         In use
FR14-004520  Set C2         In use
FR13-004469  Set D1         In use (red shielding)
FR14-004530  Set D2         In use (red shielding)

FR10-001963  Set A1         Beyond repair
FR10-001949  Set A2         Beyond repair
FR10-001964  Set B1         Beyond repair
FR10-001945  Set B2         Beyond repair

FR17-008213  Bundle G       In use (red shielding)
FR17-007647  Bundle E       In use (red shielding)
FR10-001982  Bundle F       Beyond repair
==============================================

A new 32 and new 64 set are on their way (in the ordering process).

Auxiliary equipment

 

Internal equipment (in the test room)

  • iiyaman Prolite E2273HDS 22″ 1920 x 1080 (VGA driven)
  • optical mouse, keyboard
  • 2x Tangent evo e4 Two-way speakers 10-150 W rms
  • BeyerDynamic floormicrophone MPC 66V
  • BeyerDynamic headphones DT 250 / 80 Ohm / system
  • Pan/tilt camera, wall mounted
  • Logitech c920 Webcam
  • AiPhone intercom, wall mounted

External equipment (in the control room)

EEG1 & EEG2 : 2 HP Compaq Pro 6300 MT PCs

  • HP DVD-RAM GHA3N dvd-writer
  • Dual monitor setup (vertical): 2 x iiyama Prolite E2273HDS 22″ (1920×1080)
  • Windows 7 enterprise 64-bit SP1
  • Intel Core i5-3470 CPU @3.20Ghz (4 CPUs)
  • 8 Gb Ram
  • 100Gb + 1Tb HDD
  • Intel(R) HD Integrated Graphics 2500
  • Intel(R) Integrated Audio @ High Definition Audio Device
  • PCI- multi I/O controller/NBS portdriver
  • Ms WinUsb2 driver for BioSemi ActiveTwo Card

  • Stimulation (im-lab-k13-01) & Recording (im-lab-k13-02): two HP Elitedesk 800 G2 MT
    • Dual monitor setup (vertical): 2 x iiyama Prolite E2273HDS 22″ (1920×1080)
    • Windows 10 64-bit or Kubuntu 16.04
    • 8GB DDR4-2133 (1x8GB) RAM
    • Intel Core i5-6500 3.2G 6M 2133 4C CPU
    • Intel HD Graphics 530
    • Ms WinUsb2 driver for BioSemi ActiveTwo Card (PPort card)
    • Creative Soundblaster Audigy 5/Rx (Sound card)
    • BioSemi I/O Card: optical out, ActiveTwo usb receiver
  • Aten MasterView kvm switch – csb2a
  • AiPhone LEF-3 intercom
  • procurve 1400 8port 10/100/1000Base T port switch
  • Sony integrated stereo amplifier, model: TA-FE230, 120W, super legato linear
  • Philips monitor 19pfl3405h/12 (video feed)
  • Sony Remote control RM-EV100 for 3 cameras
  • Philips remote control for TV
  • Small ‘Faraday cage’ cardboard box
    • Holds all the coiled cables to prevent them acting as antennes for electrectromagnetic noise an project it into the test room

Room details

Usage rules

Keeping the facilities in this lab in the best possible condition requires your cooperation; please read the house rules and stick to them. Especially important:

  • Never ever change or remove any wiring; don’t pull out any plugs
  • No eating or drinking (except coffee, tea, water)
  • Clean up
  • Ask for help, report all problems