Digital Referencing and Channel Mapping
Plexon’s newsletter from August 29, 2013 that discusses OmniPlex version 1.10 and its new digital referencing features.
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August 29, 2013 | |
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Plexon announces the newest software release for its flagship OmniPlex® Neural Data Acquisition System – OmniPlex Software v1.10 – containing the significant addition of sophisticated digital referencing and electrode channel mapping functionality among other improvements.
OmniPlex’s new digital referencing feature avoids many of the limitations of analog referencing. In digital referencing, the subtraction is performed by subtracting corresponding sample values in software, and there are no inherent limitations on the number of references or the number of channels that use them. Also, spike channels can be referenced independently of field potential channels without any reduction in channel count. Moreover, performing the referencing in software is a more flexible and extensible approach that allows more advanced methods to be implemented without incurring the cost and complexity of the equivalent analog circuitry.
Not only is standard digital referencing available, but OmniPlex Software v1.10 further supports two advanced methods: common average referencing (CAR) and common median referencing (CMR) performed at the full 40kHz wideband sampling rate for maximum precision. Both the OmniPlex Systems using analog amplifiers and the OmniPlex Systems with DigiAmp™ digitizing amplifiers will benefit from digital referencing if running the new OmniPlex Software v1.10.
Channel mapping allows users of electrodes with nonstandard or inconvenient physical channel numbering, such as with silicon probes, to map (renumber) the channels without the use of custom adaptors or cables which were previously required. Researchers utilizing electrodes with complex geometries such as stereotrodes or tetrodes will appreciate the convenience.
The OmniPlex Software v1.10 download is available for Windows® 7 and XP, and can be found on the OmniPlex Software webpage, or at plexon.com/software-downloads. We recommend you read the Release Notes contained within the install package to learn more regarding these and other improvements.
For more information on analog vs. digital referencing, check out the Plexon Inc Releases OmniPlex® Software v1.10 with New Digital Referencing and Channel Mapping news release. For more information regarding CAR and CMR referencing, this article can be helpful: Rolston, John D., Robert E. Gross, and Steve M. Potter. “Common median referencing for improved action potential detection with multielectrode arrays.” In Engineering in Medicine and Biology Society, 2009. EMBC 2009. Annual International Conference of the IEEE, pp. 1604-1607. IEEE, 2009.
Offline Sorter™ v3.3.1 Now AvailableOffline Sorter™ is the most recognized and trusted offline neural spike sorting software in the industry today, with more than 1,200 publications specifically citing its use. In addition to reading Plexon files PLX and PL2™ – Offline Sorter reads file types from many data acquisition companies and software programs across the industry. We just released the latest upgrade – Offline Sorter v3.3.1 – with added PL2 functionality among other improvements. Most significantly, PL2 files that are read into Offline Sorter may now also be Exported in the PL2 format in addition to being Saved. The Export function is typically used for files where spikes have been extracted from continuous data. It is important to note that neither PLX files nor non-Plexon file types can be saved as a PL2 file in Offline Sorter. Rather, the conversion from one format to another must be performed using PlexUtil 4.0 with an OmniPlex or a MAP System license key. One other improvement related to PLX files is that version 3.3.1 now sets the initial spike channel gain to be the same as continuous gain. This enhancement makes future spike extraction much easier. For more information on improvements, or to simply download the newest release, visit the Offline Sorter webpage, or plexon.com/software-downloads. The update is free of charge for those with Offline Sorter version 3 license keys. For all others, check out Plexon’s 30th Anniversary promotion offering a free license key or a discount with purchase. PlexUtil v4.0.1 Just ReleasedPlexUtil utility program version 4.0.1 has been released enhancing the manipulation of neural data files utilizing Plexon’s proprietary and game-changing PL2 file format. Plexon’s data acquisition systems generate two types of data files: PLX and PL2 files. PLX files are data files that contain action potential (spike) timestamps and waveforms, event timestamps, and continuous variable data.PL2 is Plexon’s next generation format containing all of the data within a PLX file, only further developed to significantly decrease the time it takes to read the data (single channel or block level) into a sorting or analysis program. PlexUtil is then Plexon’s file utility program that permits the manipulation of these neural data files such as creating subsets of data, merging data or converting between file formats regardless of whether the files were recorded on the flagship OmniPlex Neural Data Acquisition (OmniPlex) System or the original Multichannel Application Processor (MAP) Data Acquisition System. This latest release offers new features and improvements primarily related to the PLX to PL2 converter. PlexUtil v4.0.1 will now convert PLX files containing channels with different digitizing rates recorded by the MAP System. Moreover, the functionality associated with splitting PLX or PL2 files has been significantly enhanced providing a more seamless process. The latest download is available for both Windows 7 and XP operating systems, and can be found at plexon.com on the PlexUtil webpage, or at plexon.com/software-downloads. Additional details regarding improvements and other modifications are listed on the change log within the install package. New C/C++ Online Client Development KitPlexon’s C/C++ Online Client Development Kit has recently been updated and is now available online. The primary modification regards the PlexDO client API now supporting 75% more devices. PlexDO available in both C/C++ and MATLAB versions, allows a client program to control one or more National Instruments (NI) cards to perform basic digital output functions, such as setting individual bits high or low, outputting pulses, and generating clock signals. It supports several NIDAQ cards and USB devices which are included with OmniPlex and MAP systems. For a detailed list of devices supported and related instructions, please explore the Read Me file named PlexDOReadme.docx located within the C/C++ Online Client Development Kit zip file. This client software development kit (SDK) can be downloaded from the SDK tab at plexon.com/software-downloads. Save the Date: 2014 Plexon Neurophysiology and Behavior Workshop |
Plexon Recognized with 2013 Fast Tech AwardPlexon is thrilled to be recognized with the coveted Tech Titan Fast Tech Award for the fastest growing technology companies in North Texas. This represents the fifth time Plexon has been fortunate enough to receive this honor. Winners represent the thirty five North Texas companies in the technology, media, telecommunications, life sciences, and clean technology sectors that demonstrated the most impressive fiscal year revenue growth from 2010 to 2012. According to President Harvey W. Wiggins, “This acknowledgement is confirmation that as an industry leader celebrating its 30th year in business, Plexon still understands what it takes to stay on top for the long haul! We thank our customers and friends for this honor once again.” Plexon HQ Closed September 2, Labor DayIn observation of Labor Day, Plexon’s world headquarters will be closed September 2nd, 2013, with standard operations resuming the next day on September 3rd. Plexon Europe will remain open those days. Offline Sorter™ PromotionGet in on our 30th Anniversary specials for Offline Sorter (OFS) version 3! When you purchase OFS v3, choose either a special pricing (~$1,000 savings) or an extra license ($2,000+ savings). Email info@plexon.com to request a quote or place an order. This promotion expires December 20, 2013. New DocumentationCheck out a couple new/revised documents now available online: Upcoming Events• 4th Congress of the GDR Microelectrode Systems and Signal Processing for Neuroscience Meeting, October 17-18; Bordeaux, France Innovation for the Next 30 YearsPlexon continues to celebrate its 30th year serving researchers around the globe! |