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Here we use a non specific feedback after every block in the experimental phase. We plan on using an encouraging "thumbs up" emoji. Everything else is kept the same as in the baseline, study 2. Meaning we still use the specific performance feedback during the training phase.

We add a progress bar to our Finger-Tapping Random Sequence Generation Task and measure if this reduce mind wandering compared to a our baseline study (off.io/f48ya)

We add camera monitoring to our Finger-Tapping Random Sequence Generation Task and measure if this reduce mind wandering compared to a our baseline study (off.io/f48ya)

This study is number 4 in our experimental series (https://osf.io/wjvk2) This is a control study checking whether the feedback applied to our Finger Tapping Random Sequence Generation Task needs to be specific in order to improve the behavioral measures (AE and BV). This study implements a non-specific feedback after every block during the experimental session.

Performance feedback (in training only)

Online experiment with performance feedback in training- and experimental session Using the Finger-Tapping Random Sequence Generation Task (FT-RSGT)

Replicating in-lab experiments online can ensure scientific progress when physical contact is discouraged, like during the covid-19 pandemic. In this thesis, we replicated the results from Boayue et al. (2021) in-lab Mind Wandering (MW) experiment online. The task uses the Finger-Tapping Random Sequence Generation Task, a sustained attention task, equating MW with Task Unrelated Thoughts (TUTs). In addition to collecting self-reported TUTs, the FT-RSGT continuously collects Behavioural Variability (BV) and Approximate Entropy (AE), which are both related to MW. We replicated Boayue et al. (2021) in-lab results showing that we can reliably conduct MW experiments online. Moreover, by using six different versions of the task, we investigated whether giving different types of feedback to the participants could improve their task focus. The task versions were: (1) Identical to the lab-based task. (2) Performance feedback training. (3) Intermittently delivered performance feedback throughout the experiment. (4) Non-specific feedback. (5) Camera monitoring feedback and (6) progression feedback. We consistently found that specific performance feedback increased the global on-task focus as measured by our behavioural indices (AE and BV) relative to non-specific motivational feedback, leaving self-reported MW unaffected. On the other hand, progression and camera feedback increased the magnitude of the subjectively reported MW while leaving task performance unchanged. This dissociation could result from participants' exaggeration when surveilled and their novelty with the self-rating. We conclude that, during online experiments, researchers may want to incorporate performance feedback to increase behavioural indices. These insights may apply to other situations where increased task performance is desired. All data, experimental materials, and pre-registrations are available at the Open Science Framework (https://osf.io/wjvk2).

The motions of tectonic plates in Earth’s deep past can uncover planetary cycles of water and heat that are important for the evolution of our planet. In this thesis water exchange between Earth’s oceans and deep interior (see figure) was estimated, and there was likely a loss of seawater to the mantle corresponding to ~130 m of sea level drop since ~230 Myr ago. Maps of ancient ocean basins were reconstructed, extending back 400 Myr, and used to infer variations in seafloor depth. The ocean basin volumes estimated from the reconstructions agree well with the paleo-record of global sea level change. Seafloor reconstructions also tell us about past heat loss from Earth’s interior, and the models suggest that the Pacific side of Earth’s interior has been cooling at a much higher rate than its African counterpart during the last 400 Myr. This asymmetry was caused by the assembly of nearly all thick and insulating continental landmasses into the Pangea supercontinent on the African hemisphere, leaving the Pacific side to diffuse heat through relatively thin seafloor. These findings contribute to the understanding of how plate tectonics influences both Earth’s surface (e.g. sea level) and deep interior through geologic time.

The mechanical behavior of the heart has been modeled for decades by using continuum mechanics and numerical methods. A widely used, but rarely discussed, assumption is that inertial effects can be neglected in these models. This M. Sc. project investigates the consequences of including inertial effects in modeling of left ventricular mechanics. A framework for simulating the complete cardiac cycle is implemented using the Python interface to FEniCS. Numerical experiments are performed to study the role of inertia. The constitutive model for the myocardium suggested by Holzapfel and Ogden will be used, along with a rule-based algorithm for assigning muscle fiber orientations to the ventricular geometry, by Bayer et al. Hozapfel and Ogden’s model assumes the myocardium to behave like an elastic material, despite strong evidence suggesting viscoelastic behavior. To see how inertial effects relate to rheology we propose a viscoelastic model for the myocardium, based on a generalization of the 1D Kelvin-Voigt material model. Employing the elastic model, while including inertial effects, led to unphysiological oscillations in the ventricular walls caused by the rapidly increasing pressure load during the diastole. The wall oscillations further led to oscillations in intraventricular volume and pressure. If instead the viscoelastic model is used, the wall oscillations are damped and no oscillations in the pressure and volume curves are observed.