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Flexible adaptive paradigms for fMRI using a novel software package 'Brain Analysis in Real-Time' (BART).

Hellrung L, Hollmann M, Zscheyge O, Schlumm T, Kalberlah C, Roggenhofer E, Okon-Singer H, Villringer A, Horstmann A - PLoS ONE (2015)

Bottom Line: This can have a significant impact on the results.Our fMRI findings clearly show the benefits of an adapted paradigm in terms of statistical power and higher effect sizes in emotion-related brain regions.This can be of special interest for all experiments with low statistical power due to a limited number of subjects, a limited amount of time, costs or available data to analyze, as is the case with real-time fMRI.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig,Germany; Leipzig University Medical Center, Leipzig, Germany.

ABSTRACT
In this work we present a new open source software package offering a unified framework for the real-time adaptation of fMRI stimulation procedures. The software provides a straightforward setup and highly flexible approach to adapt fMRI paradigms while the experiment is running. The general framework comprises the inclusion of parameters from subject's compliance, such as directing gaze to visually presented stimuli and physiological fluctuations, like blood pressure or pulse. Additionally, this approach yields possibilities to investigate complex scientific questions, for example the influence of EEG rhythms or fMRI signals results themselves. To prove the concept of this approach, we used our software in a usability example for an fMRI experiment where the presentation of emotional pictures was dependent on the subject's gaze position. This can have a significant impact on the results. So far, if this is taken into account during fMRI data analysis, it is commonly done by the post-hoc removal of erroneous trials. Here, we propose an a priori adaptation of the paradigm during the experiment's runtime. Our fMRI findings clearly show the benefits of an adapted paradigm in terms of statistical power and higher effect sizes in emotion-related brain regions. This can be of special interest for all experiments with low statistical power due to a limited number of subjects, a limited amount of time, costs or available data to analyze, as is the case with real-time fMRI.

No MeSH data available.


Related in: MedlinePlus

Exemplarily results for the increase of effect sizes due to adaption.In the ROI analysis for non-adapted vs. adapted picture presentations based on regions involved in emotional processing (main effect of emotion, Fig. 6) we found enhanced brain responses for adapted trials in Low-Compliant which, due to the adaptation, met the activation levels in High-Compliant. This picture shows this exemplarily for the right pulvinar and insula, the results are summarized in Table 2.
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pone.0118890.g008: Exemplarily results for the increase of effect sizes due to adaption.In the ROI analysis for non-adapted vs. adapted picture presentations based on regions involved in emotional processing (main effect of emotion, Fig. 6) we found enhanced brain responses for adapted trials in Low-Compliant which, due to the adaptation, met the activation levels in High-Compliant. This picture shows this exemplarily for the right pulvinar and insula, the results are summarized in Table 2.

Mentions: To illustrate the neural alterations due to the adaptation for the relevant brain regions of the emotional task, we directly compared the effect sizes for adapted and non-adapted trials in High- and Low-Compliant for relevant emotion-related regions. Therefore, we extracted the coordinates for the regions-of-interest (ROIs) from the main effect of emotion to compare the average signal from a 3 mm sphere between the adapted and non-adapted condition. Fig. 8 depicts the differences between Low- and High-Compliant for two representative examples, the right pulvinar and the insula cortex. In Low-Compliant, both adapted negative and neutral pictures led to significantly higher effect sizes compared to non-adapted trials. The adaptation of the picture presentation appeared to enhance the neural activation in these regions to the same activation level as observed in High-Compliant, again underlining the beneficial effect of adaptation.


Flexible adaptive paradigms for fMRI using a novel software package 'Brain Analysis in Real-Time' (BART).

Hellrung L, Hollmann M, Zscheyge O, Schlumm T, Kalberlah C, Roggenhofer E, Okon-Singer H, Villringer A, Horstmann A - PLoS ONE (2015)

Exemplarily results for the increase of effect sizes due to adaption.In the ROI analysis for non-adapted vs. adapted picture presentations based on regions involved in emotional processing (main effect of emotion, Fig. 6) we found enhanced brain responses for adapted trials in Low-Compliant which, due to the adaptation, met the activation levels in High-Compliant. This picture shows this exemplarily for the right pulvinar and insula, the results are summarized in Table 2.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4383593&req=5

pone.0118890.g008: Exemplarily results for the increase of effect sizes due to adaption.In the ROI analysis for non-adapted vs. adapted picture presentations based on regions involved in emotional processing (main effect of emotion, Fig. 6) we found enhanced brain responses for adapted trials in Low-Compliant which, due to the adaptation, met the activation levels in High-Compliant. This picture shows this exemplarily for the right pulvinar and insula, the results are summarized in Table 2.
Mentions: To illustrate the neural alterations due to the adaptation for the relevant brain regions of the emotional task, we directly compared the effect sizes for adapted and non-adapted trials in High- and Low-Compliant for relevant emotion-related regions. Therefore, we extracted the coordinates for the regions-of-interest (ROIs) from the main effect of emotion to compare the average signal from a 3 mm sphere between the adapted and non-adapted condition. Fig. 8 depicts the differences between Low- and High-Compliant for two representative examples, the right pulvinar and the insula cortex. In Low-Compliant, both adapted negative and neutral pictures led to significantly higher effect sizes compared to non-adapted trials. The adaptation of the picture presentation appeared to enhance the neural activation in these regions to the same activation level as observed in High-Compliant, again underlining the beneficial effect of adaptation.

Bottom Line: This can have a significant impact on the results.Our fMRI findings clearly show the benefits of an adapted paradigm in terms of statistical power and higher effect sizes in emotion-related brain regions.This can be of special interest for all experiments with low statistical power due to a limited number of subjects, a limited amount of time, costs or available data to analyze, as is the case with real-time fMRI.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig,Germany; Leipzig University Medical Center, Leipzig, Germany.

ABSTRACT
In this work we present a new open source software package offering a unified framework for the real-time adaptation of fMRI stimulation procedures. The software provides a straightforward setup and highly flexible approach to adapt fMRI paradigms while the experiment is running. The general framework comprises the inclusion of parameters from subject's compliance, such as directing gaze to visually presented stimuli and physiological fluctuations, like blood pressure or pulse. Additionally, this approach yields possibilities to investigate complex scientific questions, for example the influence of EEG rhythms or fMRI signals results themselves. To prove the concept of this approach, we used our software in a usability example for an fMRI experiment where the presentation of emotional pictures was dependent on the subject's gaze position. This can have a significant impact on the results. So far, if this is taken into account during fMRI data analysis, it is commonly done by the post-hoc removal of erroneous trials. Here, we propose an a priori adaptation of the paradigm during the experiment's runtime. Our fMRI findings clearly show the benefits of an adapted paradigm in terms of statistical power and higher effect sizes in emotion-related brain regions. This can be of special interest for all experiments with low statistical power due to a limited number of subjects, a limited amount of time, costs or available data to analyze, as is the case with real-time fMRI.

No MeSH data available.


Related in: MedlinePlus