MEDUSA© Platform

MEDUSA© Panels

Here you have a detailed explanation about the four main panels of MEDUSA© Platform: real-time plots, log, apps and studies panels.

For MEDUSA© Platform v2025

If you have any questions that are beyond the scope of this help file, please feel free to ask for help in the forum or contact with us.

Real-time plots panel

The right side of the MEDUSA© main screen displays the “Real-time plots” section, where you can monitor signals as they are recorded. The display is fully customizable, allowing you to adjust the number of plots, their layout, and other features to fit your needs. MEDUSA© offers four categories of real-time plots:

  • Time-Based Plots: Display the time courses of one or more channels.
  • Frequency-Based Plots: Show the power spectral density (PSD) of one or more channels.
  • Spectrogram-Based Plots: Provide a time-frequency visualization of incoming data, including spectrograms and power distribution.
  • Head-Based Plots: Visualize signal activity across channels on a head model, including topographic maps and connectivity metrics.

Each plot type comes with multiple configuration options, allowing you to adapt them to the requirements of your study. Next, let's see how to add plots to the MEDUSA© window and customize them!

Configuring the plot window layout

First of all, you need to consider how many charts you want to create and their size. To do so, the first step is to click the button (remember to set up the LSL signal first!).

Main GUI of MEDUSA© Platform

The window below will appear. In the upper left corner, you can set the size of the grid to accommodate different plots. To create a new plot, click the button in the upper right corner. Existing plots can be deleted by dragging them to the icon in the upper right corner. Clicking the button will remove all existing plots. The button in the upper left corner allows you to add new tabs, where additional plots can be added. Load and Save buttons restore and save a specific plot layout, respectively. The OK button applies the current layout, while the Cancel button discards changes and closes the window.

Configuration screen for plot layout

Now that you know what all the buttons do, let's create some graphs! To start, click the button in the upper right corner. A light gray square will appear, indicating the position of the newly created graph. You can move it by dragging it across the grid, and resize it by dragging its bottom-right corner. The figure below shows a step-by-step example.

Configuring the plot options

Once the plot layout is configured, it is time to set up each graph. Configured plots will turn green, indicating they are ready for use. To configure a graph, right-click on it to open the configuration window shown below. In this window, you can select the source data from the Connect to dropdown, and choose from eight different options in the Plot type list.

Configuration screen for the plot options

Below the Plot type list, there are two sections where you can complete the configuration of the plot.

On the one hand, in Preprocessing options, different transformations can be applied to the original signal to adapt the representation to your study (e.g., a bandpass filter if you are interested in a certain frequency band).

  • min_update_time: Controls the minimum time interval (in seconds) between plot updates. Lower values result in more frequent updates but increase computational load.
    If plots are slow, unresponsive, or stop updating, try increasing this value. The optimal setting depends on your computer’s performance and the complexity of the selected plots.
  • channel_selection: List of channels considered for visualization. This setting is updated automatically based on the available input streams.
  • frequency_filter: Configures an optional IIR filter for real-time visualization. Enable it with apply, select the filter type, define the cutoff_freq, and adjust the order.
  • notch_filter: Optional notch filter to suppress narrowband interference (e.g., power-line noise). Define a center frequency using freq and relative limits using bandwidth.
  • re_referencing: Changes the signal reference. Use car for Common Average Reference or channel to subtract a specific channel from all others.
  • downsampling: Reduces the sampling rate of the incoming LSL stream to lower the computational cost of real-time plotting.

All visualization filters are implemented as IIR filters to ensure efficient real-time performance. While IIR filters introduce non-linear phase effects, their lower computational cost makes them well suited for online visualization. For a comparison with FIR filters, see this reference .

On the other hand, the Visualization options section controls the plot's appearence.

  • title: Allows you to configure the plot title. Use text to define a custom title or auto to generate it automatically, and fontsize to adjust its size.
  • x_axis: Configures the x-axis label, including its text and fontsize.
  • y_axis: Configures the y-axis label, including its text and fontsize.

Time-based plots display signals along the time axis, allowing you to monitor how signals evolve in real time. You can view multiple channels simultaneously with Time (multi-channel) or focus on a single channel with Time (single-channel).

Specific parameters in the Visualization options of these plots are:

  • x_axis: Includes seconds_displayed to adjust the time range to be shown, and grid settings for which you can choose whether to display the grid or not, and the separation between lines (step) if applied.
  • y_axis: Includes the grid settings, cha_separation to adjust the spacing between channels, and autoscale settings for which you can enable automatic scaling (apply) or adjust the scale manually using the mouse wheel.
  • mode: This parameter determines how events are presented in the graphics. You can choose between Clinical, where the display grid updates in a sweeping manner, or Geek if you prefer the signal to appear continuously.
  • init_channel (only for Time (single-channel)): Selects the channel that is displayed initially. You can also change it interactively by clicking on the plot and selecting a new channel.

Frequency-based plots display the power spectral density (PSD) of the signals, showing how power is distributed across different frequencies. You can view multiple channels with PSD (multi-channel) or focus on a single channel with PSD (single-channel).

Specific parameters in the Preprocessing options of these plots are:

  • psd: Controls the PSD estimation. time_window sets the time interval over which the PSD is computed, welch_seg_len_pct defines the segment length as a percentage of the window, welch_overlap_pct sets the overlap between consecutive segments, and log_power enables displaying the PSD in dB (10*log10).

The estimation of the PSD is carried out following the Welch method. Click here for further explanation, and here for learning more about the Python implementation.

Specific parameters in the Visualization options of these plots are:

  • x_axis: Includes range to set the frequency limits of the PSD, and grid settings for which you can choose whether to display the grid or not, and the separation between lines (step) if applied.
  • y_axis: Includes the grid settings, cha_separation to adjust the spacing between channels, and autoscale settings for which you can enable automatic scaling (apply) or adjust the scale manually using the mouse wheel.
  • init_channel (only for PSD (single-channel)): Selects the channel that is displayed initially. You can also change it interactively by clicking on the plot and selecting a new channel.

Spectrogram-based plots display the time-frequency representation of the signal, showing how the spectral content evolves over time. You can view this with Spectrogram or analyze cumulative power across bands with Power Distribution.

Specific parameters in the Preprocessing options of these plots are:

  • spectrogram: Controls the rolling spectrogram computation. time_window sets the duration of data kept in the buffer, overlap_pct defines the overlap between segments for the computation, scale_to selects the output scaling (psd or magnitud), smooth enables Gaussian smoothing, smooth_sigma sets the sigma of the Gaussian kernel, and log_power controls whether the spectrogram is displayed in logarithmic scale.
  • power_distribution (only for Power Distribution): Defines the frequency bands to be displayed. band_labels names the frequency bands, and band_freqs sets the corresponding frequency ranges in Hz for each defined band.

Specific parameters in the Visualization options of these plots are:

  • x_axis: Includes seconds_displayed to adjust the time range to be shown, and grid settings for which you can choose whether to display the grid or not, and the separation between lines (step) if applied.
  • y_axis: Includes the grid settings and range to set the limits of the axis.
  • z_axis: Controls the color scaling of the plot. cmap sets the colormap, range sets the limits of the axis, and autoscale allows you to enable automatic scaling (apply) or adjust the scale manually using the mouse wheel.
  • mode: This parameter determines how events are presented in the graphics. You can choose between Clinical, where the display grid updates in a sweeping manner, or Geek if you prefer the signal to appear continuously.
  • init_channel (only for Time (single-channel)): Selects the channel that is displayed initially. You can also change it interactively by clicking on the plot and selecting a new channel.

Head-based plots provide a topographical view of the signals recorded across the scalp, allowing you to visualize spatial distributions and functional connectivity. You can examine the activity of multiple channels simultaneously on a scalp map with Topography or explore the interactions between channels with Connectivity.

Specific parameters in the Preprocessing options of these plots are:

  • power_range: Frequency range used for computation.
  • psd (only for Topography): Controls the PSD estimation. time_window sets the time interval over which the PSD is computed, welch_seg_len_pct defines the segment length as a percentage of the window, welch_overlap_pct sets the overlap between consecutive segments, and log_power enables displaying the PSD in dB (10*log10).
  • connectivity (only for Connectivity): Parameters to configure functional connectivity. Includes time_window in seconds for the estimation and conn_metric to select the connectivity measure. Available metrics are Amplitude Envelope Correlation (aec), Phase-Locking Value (plv), Phase Lag Index (pli), or Weighted Phase Lag Index (wpli).

Specific parameters in the Visualization options of these plots are:

  • head_plot: Group of parameters to configure the head display and channel markers. Includes:
    • channel_standard: EEG electrode montage used to position channels on the scalp.
    • head_radius: Relative radius of the head, controlling the overall size of the scalp representation.
    • head_line_width: Width of lines used to draw the head outline, ears, and nose.
    • head_skin_color: Fill color for the head area.
    • plot_channel_labels: If True, channel labels are displayed on the plot.
    • label_color: Color used for the channel label text.
    • plot_channel_points: If True, markers are drawn at each channel position.
    • channel_radius_size: Determines the size of the channel markers. Set auto to automatically compute the radius, or define a custom value when automatic sizing is disabled.
  • z_axis: Controls the color scaling of the plot. cmap sets the colormap, range sets the limits of the axis, and autoscale allows you to enable automatic scaling (apply) or adjust the scale manually using the mouse wheel.
  • topography (only for Topography): Settings specific to topographic maps. Includes interpolate to generate a smooth map between channels, extra_radius to define additional area beyond the head for interpolation, interp_neighbors to set the number of nearest neighbors used at each grid point, interp_points to define the resolution of the interpolation grid, and interp_contour_width for the line width of contour lines drawn over the topographic map.
  • connectivity (only for Connectivity): Settings specific to connectivity plots. Includes percentile_th, which controls the threshold for displaying connections; only connections above the specified percentile are shown in the plot.

Visualizing the Final Layout

Now that you know how to configure the plots, let's arrange the layout as follows:

Tab 1

  • 0: Time (multi-channel)
  • 1: PSD (single-channel)
  • 2: Topography
  • 3: Connectivity

Tab 2

  • 0: Spectrogram
  • 1: Power Distribution

The plot layout will now be green, as shown in the figure below. It's time to press the OK button and visualize our signals.

Plot layout with all the graphs already configured

After pressing the OK button, you may notice that the charts do not immediately display. That’s okay, simply click the button to activate the visualizations. You can toggle the visualizations on or off at any time by clicking the same button. Additionally, you can modify your plots whenever they are deactivated by clicking the button.

Log panel

The left-hand corner of MEDUSA Platform refers to the log panel. Within this panel, users can see a chronological record of events that have had an impact on the platform. These logs not only document the events themselves but also provide insights into the resulting changes and consequences that these events have generated.

Log panel of MEDUSA© Platform
  • This option enables you to save the text file generated from the logs into the folder of your choice. It server as a valuable function for archiving or backing up the log data in a location that you specify.
  • Clears the screen where the notifications are generated. It is particularly useful for maintaining a clutter-free and distraction- free workspace by removing outdated or redudant information.
  • Log settings. Still under development.
  • This feature allows you to adjust the size of the console, which can be valuable for adapting the user interface to your specific preferences or needs. You can expand or shrink for a more comfortable user experience.

    • Apps panel

    A comprehensive list of all the applications included in the platform is displayed in this panel. The apps are listed in order of installation. Detailed information on the necessary configurations of each application can be found in their respective documentation.

    Apps panel of MEDUSA© Platform

    In the first block:

  • After selecting the desired application from the list, this button will allow the app to be started.
  • Once the application has been launched and a TCP/IP connection established, this button provides the functionality to initiate or pause the app.
  • Ends the app and immediately a save recording file box appears to save our signal in the folder indicated.
  • This button offers the capability to adjust various parameters corresponding to each individual application.
  • On the left-hand side, you can conveniently highlight a specific application by typing its name in the provided search box. This simplifies the process of locating and accessing desired applications.
  • Allows you to install a new application on the platform. To accomplish this, you should select the .app within the appropriate file folder.

    • The second block, which contains the central icons, focuses on session creation and management. Through this feature, you can create customized sessions that include various applications with different paradigms, each with its own configuration settings.

  • Load session Allows to load a pre-configured session for the different applications.
  • Play session Initiates the configured session.
  • Configure session Modify the specified parameters of an existing session.
  • Create session Facilitates the creation of a new session by allowing the input of various parameters:

    • Panel where you can configure each session.

    Click on + to add the new parameters. The parameters to modify:

  • RUN ID The name assigned to the run.
  • APP ID The identifier of the application to be referenced. A tab will open where you can select the required application (must be installed on your MEDUSA© platform).
  • Settings file Allows to load a previously saved configuration.
  • Max time(s) Define the maximum runtime for the application, particularly beneficial for apps configured to run indefinitely.
  • File ext Extension indicating the type of format of the file (bson, mat or json).
  • Autoplay If enabled, the application will launch automatically after the previous one, bypassing the need for the user to click the play button.

    • Below the box, you can choose to automatically update the default record IDs, ensuring that the application refreshes whenever changes are detected.

    In the Preference tab, there is an option to enable or disable study mode, which enables potential visualization of the desktop folder corresponding to our created session. Lastly, in Edit recording info you have the opportunity to configure recording details and establish parameters such as recording ID, file extension and file path. This streamlines the process of saving recordings and allows for the inclusion of supplementary information, such as studio ID, subject ID, session ID and studio information, enhancing the overall recording experience.

    Studies panel

    The "Studies" panel is designed to help manage folders in research projects. It is extremely useful for managing data and recordings in large-scale experiments. It allows folders to be prepared in advance and automatically saves session recordings in the appropriate directories, reducing human errors, preventing missing files, and improving data management and experiment automation. To access this panel, the first step is to enable study mode. To do so, click on Preferences in the top-left corner of the platform and click on activate study mode.

    Main GUI of MEDUSA© Platform

    After enabling this mode, the following panel will appear. The first step is to click on and select the root directory of your project. By default, the selected root directory is the data folder from MEDUSA©. By clicking on , the files in the selected root directory will be updated.

    Studies panel of MEDUSA© Platform

    The studies management structure is designed as follows: data → study → user → session. In the following GIF, an example shows how the panel looks using this project structure.

    Example of project management within the studies panel

    During an experiment, you can select from this panel which user and session will be recorded. All recordings will be saved by default in the selected root directory. Regardless of whether the data → study → user → session hierarchy is strictly followed, the folder selected in the "Studies" panel will always be used as the default directory for saving experiment recordings. Therefore there is no need to follow the proposed struture and any structure is valid.

    As shown in the example, if a data file exists at the user level, its contents will be visible directly in the panel, which can help to identify the user more easily.

    From the file browser perspective, the structure of the files in the previous example is shown in the following GIF.

    Example of project management from the file browser view