| ANT Newsletter, July, 2008 |
We are pleased to send you the latest edition of our newsletter featuring the following topics:
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Human Brain Mapping Conference 2008, Melbourne, Australia  ANT would like to thank everyone that participated in the ANT & Medilink reception held on June 17th during the Human Brain Mapping conference. After a short introduction of ANT by Frank Zanow, this reception became a great opportunity to meet new faces and discuss various topics including the European soccer tournament, our Neuronavigaton system (Visor), and our solutions for EEG/MRI combined recordings. We enjoyed meeting all of you during this event! All of your questions were appreciated and we are looking forward to future collaborations. We hope to meet you again during the next Human Brain Mapping conference in San Francisco or at any of the below mentioned conferences. Again, thank you for joining us! If you have any further questions, or are interested in a demonstration of one of our systems, please email us at sales@ant-neuro.com | ||
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ASA Workshop, Gent, Belgium May 30th an ASA user meeting was held in Gent, Belgium. This workshop was organized in collaboration with Prof. L. Boullart (University of Gent), Prof. P. Santens (University Hospital Gent) and Dr. G. Otte (Psychiatric Center P.C. Guislain in Gent). Frank Zanow, Manon Boeschoten and Jaap van der Spek of ANT gave the presentations and led the hands-on sessions. Around 25 people were present at the meeting, from various countries.The topics that were covered in this workshop were: ASA recording and ERP analysis, source reconstruction in ASA, wavelet analysis in ASA and setting up and processing ERP studies in Experiment Manager. Furthermore, special topics were BCI / Neurofeedback as well as exporting data from within Cognitrace to ASA or Experiment Manager, in order to either analyze the data on a single patient basis or for the entire group of patient data. We would like to thank all participants for attending and we hope to organize a similar workshop in the nearby future. | ||
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Validation of TMS Motor Mapping with Visor The question to what extent the mapping of motor control regions in the brain can be accurately mapped using navigated TMS is of great practical relevance for clinical applications. This has been recently studied in a collaborative effort of ANT and Twente University, Enschede NL. Ms Leonie Melching, a student at the University of Twente, recently finished a three-month research project in which neuronavigation with Visor was validated against functional MRI obtained at the FC Donders Centrum in Nijmegen. Below the summary of her internship:TMS motor mapping using the Visor system Motor mapping is a common procedure in Transcranial Magnetic Stimulation (TMS) to determine the site and the size of motor cortex representations. It can be used to demonstrate patterns of functional reorganization in the brain, and to provide an accurate reference for stimulus administration during therapeutic management. The Visor NeuroNavigation system for TMS (www.ant-neuro.com/products/visor) indicates the location of the coil and the stimulation area on the brain to guide the stimulation. In combination with a system for recording Motor Evoked Potentials (MEP), Visor can visualize the MEP amplitude on the brain surface. In a pilot study, 3 subjects participated in 3 TMS individual sessions, and one fMRI experiment. TMS motor mapping using the Visor system was performed by stimulating on a square grid of approximately 5x5 cm over the hand area on the motor cortex, contralateral to the dominant hand, at a resolution of 3 mm. The MEPs of the thumb were recorded for each stimulated grid point. fMRI was recorded during repeated abduction of the thumb. The Center of Gravity (CoG) for the "thumb-maps" were compared to the CoG in the fMRI results. The mediolateral spatial shift for the fMRI maximum as compared to the MEP CoG was less than 11 mm in all 3 subjects, located consistently more posterior. This can be explained from the activation of the somatosensory cortex (located posterior to the motor cortex) during the voluntary thumb movement (bottom-up process) which was absent in the TMS-induced MEP activations (top-down stimulation). The accuracy and reproducibility of the TMS navigation was demonstrated very clear in one of the subjects: the CoG between sessions showed a difference of only 0.2 mm in mediolateral direction and 0.1 mm in occipital frontal direction. The motor maps in the other two subjects were more diffuse. These initial results indicate the usefulness of the combination of real time motor mapping and TMS navigation using the Visor NeuroNavigation system.  Figure 1: MEP intensity map for the thumb response in one of the subjects (gray scale in µV). Each square on the grid corresponds to a stimulation point. Near the edges of the grid a lower resolution in spacing was used to shorten the TMS session; the white rows and columns were not stimulated, thus not plotted.  Figure 2: fMRI result for repeated thumb movement.  Figure 3: Neuronavigation: coil position, stimulation area and MR image are integrated.  Figure 4: Maximum MEP "hotspot" and fMRI maximum. | ||
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Why ANT? - Testimonial from ANT user Let the customers speak - Under this motto, we would like to give the word to customers of ANT in this newsletter column. We sincerely hope that this will help readers in the decision-making process and may stir some ideas when it comes to possible cooperation with ANT."The Cognitive Neuroscience Group of Amsterdam is using TMS to investigate the nature of conscious visual perception. How does it work? How long does the brain take to process stimuli up to a level of consciousness? What can the brain do without conscious awareness? The use of fMRI, EEG/MEG and TMS makes it possible to link neural activity to consciousness- related processes. But how can these neural correlates of consciousness be investigated? Our experiments focuses on establishing what processes and what areas are (and what areas are not) necessary for the emergence of visual awareness. In order to unravel the mysteries of visual awareness we wanted to use an exciting combination of TMS and EEG. For the placement of the coil and to know how and where you are stimulating we needed a neuronavigation system in combination with a forward field calculation. With this wish list, ANT almost automatically caught our eye. I find the company very dynamic, helpful, but most important ANT has affinity for research! The people at ANT (Frank, Robin, Michiel, Maarten, Jaap, Menno, Stephan and all the others) are always ready to help and eager to find new solutions for the problems we encounter in research." Martijn Wokke, University of Amsterdam, Cognitive Neuroscience Group | ||
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Upcoming meetings for ANT to attend and to exhibit
More information is found at http://www.ant-neuro.com/events/calendar | ||
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