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FURTHER DEVELOPMENTS

          IN MEDICAL ELECTRONICS












          AI Semantic Decoder gives Paralysed a Voice          Transforming Heart Health with Smart Data
          Assistant Professor of Neuroscience and              Researchers at Duke University, in collaboration
          Computer Science Alex Huth, along with doctoral      with computational scientists at the Lawrence
          student in computer science Jerry Tang at            Livermore National Laboratory, have made a
          the University of Texas, Austin, have together       major breakthrough in heart health monitoring
          developed an AI semantic decoder that can            by developing the Longitudinal Hemodynamic
          translate brain activity into a continuous stream    Mapping Framework (LHMF).
          of text.
                                                               Utilising the concept of ‘digital twins’ to create a
          The system utilises a transformer model similar to   detailed 3D model of a patient’s blood flow, the
          those behind Open AI’s ChatGPT and Google’s Bard     model is based on data collected over a period
          and allows brain activity to be generated while      of time covering over 700,000 heartbeats. This
          listening to a story or imagining telling a story. It does   contrasts with the present standard for heart
          not require surgical implants and is envisaged to be   disease evaluation, which typically relies on
          extremely useful for those who are mentally alert but   snapshots of single moments in time that are
          unable to speak, for example following a stroke.     insufficient for the monitoring of heart disease
                                                               because it tends to develop gradually over months
          Brain activity is measured using an fMRI scanner
                                                               or years.
          once the decoder has been extensively trained
          whilst individuals listen to hours of podcasts in the   One of the primary challenges for creating
          scanner. Once trained the decoder can interpret      these detailed simulations was the immense
          brain activity from listening to a new story or      computational power required. This was addressed
          imagining one, and produce corresponding text        by means of a software package known as HARVEY,
          that closely matches the intended text.              developed by Duke University, which allows for more
                                                               efficient processing of the complex simulations.
          The technology only works effectively with
          participants who have trained the scanner and the    By simulating heartbeats in parallel rather than
          system’s practical use is restricted to laboratory   sequentially, and breaking the task up among many
          settings due to the dependency on the fMRI           different computing nodes, the team managed to
          scanner, although the researchers believe that it    reduce what previously took almost a century of
          could in future be adapted to more portable brain-   simulation time to just 24 hours. This was achieved
          imaging systems such as functional near-infrared     by making reasonable assumptions about the lack
          spectroscopy (fNIRS).                                of impact of certain time-specific coronary flows on
                                                               others, thus allowing for the simulation of different
          Alex Huth states:
                                                               time chunks simultaneously prior to reassembling
            “ For a non-invasive method this is a real leap    them.
            forward compared to what’s been done before,
                                                               The LHMF was tested on both Duke University’s
            which is typically single words or short sentences.
                                                               computer cluster and on cloud computing systems
            We’re getting the model to decode continuous
                                                               such as Amazon Web Services. This found that
            language for extended periods of time with
                                                               errors in the LHMF simulations were negligible
            complicated ideas.”
                                                               compared to traditional methods.
          A PCT patent application has been filed for this work.
                                                               Applications for the LHMF include using it to
          [ Reference: Fowle, H., Electronic Specifier, 14th.   determine whether a patient requires a stent for
          November 2023 ]                                      the treatment of arterial plaque or lesions and



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