MEG system

The centerpiece of the MEG lab at MIT is a Triux system from Elekta, the first of its kind to be installed in North America. The scanner has a 306-channel probe unit with 204 planar gradiometer sensors and 102 magnetometer sensors, plus 128 channels for simultaneous EEG. The scanner can record subjects in three different positions: seated upright at 68 degrees, upright 60 degrees, or supine.

EEG system

The MEG system includes an 128-channel EEG system, allowing simultaneous EEG and MEG measurements. EEG caps with 64 or128 channels are available.

Three-layered magnetically shielded room

The shielded room, a modified model from Vacuumschmelze, is constructed with three layers of mu-metal for efficient passive shielding of external magnetic interference. It is equipped with Helmholtz coils for additional active noise suppression.

Visual presentation system

The lab is equipped with a high fidelity projector (Panasonic PT-D10000U). The visual signal is projected through the wall of the shielded room to a 44’’ back-projection screen that is placed in front of the subject chair.

Other resources

  • Subject communication: A two-way audio system and a CCTV monitor support communication between experimenters and the subject inside the shielded room.
  • Auditory stimulus system: A pair of tubal-insert earphones and accessories.
  • Somatosensory stimulus system: A pair of electrical somatosensory stimulators.
  • Response system: Subject responses, in the form of button presses, can be recorded with pair of 4-button response devices from Current Designs, or with a pair of one-finger laser response pads.
  • Eye tracking system: A MEG-compatable eye tracking system (Eyelink 1000) is installed within the shielded room to monitor the subjects direction of gaze during scans.
  • Patient chair and couch: Adjustable chair with separate child insert. Patient couch for supine measurements.
  • DC-13 Degausser: Decreases unwanted magnetic fields.
  • Subject preparation area with privacy curtain, linens and sink for hair-washing.
  • Data Analysis Software: Elekta Neuromag data analysis software (100 licences); Freely distributed and public domain software (Brainstorm, MEG, etc)
  • Data Analysis Workstation: HP xw6600, two 2.66 GHz Intel Core 2 Duo processors, 4GB RAM, 30-inch TFT monitor