neuroelf_gui_-_mdm_voi_condition_average_ui
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— | neuroelf_gui_-_mdm_voi_condition_average_ui [2011/04/03 03:22] (current) – created jochen | ||
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+ | ====== NeuroElf - MDM VOI condition averages ====== | ||
+ | |||
+ | ===== Motivation ===== | ||
+ | While hypothesis testing usually is done via formulating a Null-hypothesis (e.g. no systematic effect of differential processing of conditions), | ||
+ | |||
+ | One hopes to find a response shape (over time) that resembles the canonical response and, if such a shape is observed, one can have additional confidence in the findings (as opposed to observing more or less random fluctuations over time, which simply happened to " | ||
+ | |||
+ | ===== Requirements ===== | ||
+ | To use this feature in NeuroElf, the following files must be available: | ||
+ | |||
+ | * a [[xff - VOI format|VOI file]] must be loaded (using the load-clusters button in the [[NeuroElf GUI# | ||
+ | * [[xff - VTC format|VTC files]] of all runs of subjects which are to be included in the average plots | ||
+ | * [[xff - PRT format|PRT files]] describing the onsets at which stimuli of different conditions were presented | ||
+ | * an [[xff - MDM format|MDM file]] referencing those VTC and PRT files (**an MDM referencing SDM files will not work, given that the onsets are no longer available!**) | ||
+ | * optionally referenced motion parameter files and temporal filtering settings in the '' | ||
+ | |||
+ | ===== Invoking the UI ===== | ||
+ | To bring up the condition-based averaging plot, **make sure the correct list of clusters** is being displayed in the list of VOIs/ | ||
+ | |||
+ | Once an MDM is selected and loaded, NeuroElf will examine the protocol files and show a list of conditions found in those files for selection. This is a good time to remove any conditions of no interest (fixation and rating periods, active baseline, etc.) as this will speed up the subsequent computations. | ||
+ | |||
+ | Next, the time courses will be extracted for all VOIs in all VTCs in the MDM file (subject selection is implemented at a later stage). This can take up to several minutes, depending on the number of VOIs and VTCs for which this has to be done. | ||
+ | |||
+ | In case this is required by the settings (motion parameters and/or temporal filtering), design matrices will be created for the runs, so that time courses can be filtered. | ||
+ | |||
+ | Eventually, a new UI appears. | ||
+ | |||
+ | ===== GUI layout ===== | ||
+ | {{: | ||
+ | |||
+ | ===== Controls ===== | ||
+ | The following controls are available: | ||
+ | |||
+ | * Select cluster (dropdown): changes the currently shown VOI/cluster | ||
+ | * Update position (checkbox): if checked sets the current position (and cluster, unless reloaded) in the main UI to the cluster peak coordinate | ||
+ | * Grouping (dropdown) with settings **FFX**, **RFX**, and **RFX (weighted)** | ||
+ | * FFX: error bands represent fixed-effects standard deviation (SD) or standard error (SE) of the mean | ||
+ | * RFX: error bands represent random-effects SD or SE of the mean (an intermediate within-subject averaging step precedes any subsequent computation) | ||
+ | * RFX (weighted): **//this is not yet implemented!!// | ||
+ | * Select conditions (multi-selection listbox): the selected conditions will be averaged and plotted (one plotted line/band per selected condition) | ||
+ | * Condition color settings (button): this button allows to re-set the colors for each condition (as they first appear in a referenced PRT file) for visualization purposes | ||
+ | * Collapsed conditions (multi-selection listbox): the configured collapsings will be performed and averaged plots will be shown collapsed (one plotted line/band per selected collapsing) | ||
+ | * Add collapsing (button): takes the currently selected conditions and creates a collapsing configuration (requesting a name), this in effect allows to combine onsets of several conditions at a late stage instead of having to re-create protocol files | ||
+ | * Remove collapsing (button): removes the currently selected collapsings from the list | ||
+ | * Collapsed conditions color settings (button): this button allows to define new colors for each collapsing | ||
+ | * Selected groups (multi-selection listbox): if groups are configured in the '' | ||
+ | * Robust estimates (checkbox): if checked averages will be performed with outliers removed | ||
+ | * SE instead of SD (checkbox): if checked (and error bands are visualized) error bands represent SE of the mean instead of SD of the mean (allowing to relate inferential statistical outcome to plotted curves; **please note that this does not allow to draw inferential conclusions on its own!!**) | ||
+ | * Options visible (checkbox): if unchecked, all other controls are hidden and the axes is maximized to cover (almost) the entire figure (improved screenshots) | ||
+ | * Baseline window (edit field): expression indicating the (relative-to-onsets) timepoints (in seconds!) that are used to compute the baseline for each extracted window (must be in Matlab' | ||
+ | * Averaging window length (edit field): a single number indicating the length of the window being extracted (in seconds!) | ||
+ | * virtual TR (edit field): a single number indicating the virtual resolution (in seconds!) of the visualization (allowing to improve response overlap for non-TR locked designs; very small numbers will increase the computational and plotting effort!) | ||
+ | * Axes range X/Y from/to (edit fields): if the auto-scaling of the axes object is undesirable (e.g. to use the same scaling across several regions/ | ||
+ | * Error bands (checkbox): if checked, also visualize error band indicators (see also SE instead of SD setting above) | ||
+ | * Individual response lines (checkbox, unlabeled): if checked, also plot individual responses (or within-subject averages for **RFX** setting; in the FFX case this can mean that **VERY** many lines are plotted, slowing down the UI!) | ||
+ | * Background color setting (button): this button can be used to alter the background color of the axes | ||
+ | * Error bands alpha setting (edit field): this number is used to set the alpha (transparency) property of the error bands | ||
+ | |||
+ | ===== Menu ===== | ||
+ | The following functions are available via a menu: | ||
+ | |||
+ | * **File** | ||
+ | * **Save extract datafile...** - stores the MDM/VOI content along with the extracted timecourses (and optionally created SDMs) and all settings to a '' | ||
+ | * **Save figure screenshot...** - calls the private screenshot function of NeuroElf, requesting a filename, saving the figure as an image | ||
+ | * **Save axes screenshot...** - moves the axes object to a new figure and then calls the private screenshot function of NeuroElf, requesting a filename, saving the axes object incl. the scale and title as an image | ||
+ | * **Data** | ||
+ | * **Set Data in Base Workspace** - make the data currently used available in the base workspace | ||
+ | * **Options** | ||
+ | * **Legend position** - allows to alter the position of the legend sub-axes to either of the four axes corners | ||
+ | * **Subject selection** - brings up a listbox selector ('' | ||
+ | |||
+ | ===== High-quality screenshot example ===== | ||
+ | Using the File -> Save axes screenshot... menu item, it is possible to create high-quality plots by choosing the **Encapsulated PostScript (.eps)** format and then loading the EPS file into a graphics program (e.g. Adobe Photoshop or The GIMP). The above screenshot is then rendered (at any desired resolution), | ||
+ | |||
+ | {{: | ||
neuroelf_gui_-_mdm_voi_condition_average_ui.txt · Last modified: 2011/04/03 03:22 by jochen