When used together with Polhemus digitizing hardware, LOCATOR allows you to measure accurately electrode locations an external head shape in 3 dimensions. These data may then be used for MRI coregistration and more accurate source estimation. LOCATOR currently supports two Polhemus products: FASTRAK and PATRIOT.

Functionality

3D Digitization

• Electrode locations may be determined by touching with a stylus.
• Head movement is automatically compensated with 1-3 head mounted sensors.
• External head shape locations may be determined by “drawing” over the head surface with a stylus. Head movement is automatically compensated with 1-3 head mounted sensors.
• Location of named points (such as nasion, inion, etc) may be obtained and stored.
• Sensor and fiducial names can be read out loud in any language to minimize the need to monitor the Locator software display during digitization.
• BESA, Curry, and EMSE formats are supported.^*
• Other sensors (including optical sensors and magnetic sensors) may also be digitized.
• Setup functions for Polhemus hardware (PATRIOT and FASTRAK) are available through the LOCATOR menu.
• Locator can warn the user when the stylus has been moved during digitization (based upon user-specified threshold)
• Operator may back up and repeat digitization of points already completed.

Display

• 3D display after digitizing permits viewing of digitized points.

Input/Output

• User Interface. A conventional Microsoft Windows style graphical user interface is used throughout.
• Audio prompt allows you to digitize electrodes from a sequence file without looking at the screen.

Intermodule Communication

• Input: None
• Output: Measured locations may be used for 3D rendering of sensors on a head surface, and for source estimation in EMSE SOURCE MRI.

File I/O

• Input: ASCII setup files may be used to store commonly used sequences (e.g. electrode names).
• Output: ASCII (EMSE format) probe and headshape files; BESA and Curry ASCII export formats*

Other I/O

• Graphics may be transferred to clipboard for use by other graphics programs or for insertion into word processors.

Documentation

• Printed. User manual, including file formats.
• Online documentation is bundled with the software.