November 2018 – Finally the EEG experiment

So, it’s beginning of January and only now I have time and energy to write the wrap up of November (and December). In general November has been very creative in research, teaching and outreach. But let’s take it from the top.


November started with unresolved issues in the Matlab script, related to stimulus presentation. I have extensive notes of the first couple of days, because I had to keep track of the solutions I’ve already tried, in order to avoid losing time on re-trying things that didn’t work out. Looking into Matlab code generally makes me dizzy, but at least I managed to navigate and eventually solve the issues. I ran the whole experiment on myself and discovered some missing files and some typos that needed to be fixed. One of the audio files needed to be re-recorded, as it included a mispronunciation of a name in only one part of the story. Luckily, the speaker was available in Maastricht, so he passed by and we wrapped up the recording in 15 minutes. Then I normalized that file and included it to the list of audio files. I also fixed the typos and balanced the correct answers to half option a and the other half option b.

My initial experimental script was doing the normalization in the stimulus presentation script and the resulting normalized files were only peak-normalized. This ended up not having the same loudness across files. With the valuable help of my collaborator Thanos, who explained how to do a two-step normalization, I made a short script which normalized the files in peak and loudness externally from the experimental script. Then, in the experimental script I only load and play the files without needing to normalize them anymore. In mid November I sent the normalized files to Thanos, so that he runs his auditory analysis algorithms on the signal.

We then determined how to analyze the audio signal, based on Thanos’s previous research and its relevance for cognitive functions. In my email to Thanos I wrote:

I see that the most prominent features given the theory on speech rhythm, such as the period of the strongest peak (beat), do not perform so well in the automatic language identification task in all the corpora you tested. This might at first be surprising, but the difference should be viewed, as you already discussed in the paper, under the task performed by the classification algorithm and the fact that the algorithm might not be reflecting cognitive processes.

Given these, I would like to suggest that we take all the beat histogram features for our analysis and use them in two ways:

  1. to test whether the algorithm can discriminate between conditions, poem vs. story and which features are the most prominent in this classification.
  2. then, to take the most cognitively motivated features, e.g. amplitude and F0, and compare their fit to the EEG data.

We decided to compute all the novelty functions based on the beat histograms, as laid out in Thanos’s 2015 paper. We would then discuss that we can do with features like spectral flux or spectral flatness, which do not seem to be relevant for cognition, at least for the moment, but seemed to contribute very much to the classification between languages.

On November 20th, I had a second project proposal meeting with the TMS group, in which I outlined the details of the experimental setup. The group recommended me to be cautious about: preparation of the subject (the gel would dry out when applying the TMS), how to optimize procedures so that we are fast and effective, use a TMS compatible cap, how to localize the pre-SMA for each participant. In my meeting with Teresa on November 23rd, she stressed that the most important thing is how we localize the pre-SMA, whether we need a structural MRI and look in each brain for the specific co-ordinates, or whether it is an easy area to localize, such as other motor regions, and does not need an MRI scan. She advised me to look into previous studies which have targeted the pre-SMA and check the methodological details. I have to complete and send back the NIBS Project Proposal Form before we start measuring for NERHYMUS.


Most of the students of the writing skills course submitted their Introduction on time on November 9th. I was amazed at the general low quality of the essays. However, after I visited the course on how to evaluate and give feedback for writing skills and theses, I realized that the students are just starting to understand how scientific writing is expressed and how to write in this form themselves. So, I re-evaluated my initial evaluation, and made an effort to give my students meaningful feedback on how to improve, rather than dismissive general comments. From the individual short meetings for providing this feedback I had the impression that the students truly appreciated my effort and that it helped them understand what they did wrongly and how to improve.

With regard to the mentoring course, I had the impression that the second mentor meeting was a disaster. Even though I did my best to follow the instructions of the course administrator, I felt that the students were not interested, as the session was very much just repeating the content of the first session. The general impression was that what we did in the scheduled 2 hours, could have easily been done in 1 hour without needing to overtire the students with repetition. Maybe it was also the wrong time of the day for such a task, as 4-6pm in the late afternoon is quite late. I have forwarded this feedback to the colleagues who planned the course and hope that this session will be planned differently for next year.


We’ve made a lot of progress with Pint of Science Maastricht. In mid November, Lena and I met with Danielle Vogt and Flore Clerx from the Marketing and Communications of the FHML, who really helped us to pitch our call for volunteers in a fun manner. They were also very supportive of Pint of Science Maastricht in general and they suggested to hold a general info session in the Turnzaal in January and have media coverage and possibly interviews to spread the word about the festival. Lena worked with them on the text for the university-wide call for participation and we sent it out at the end of November.

On November 27th I held the first info meeting in a small circle with people from NP&PP and CN. The goal of this meeting was not only to inform, but also to recruit volunteers for the taster event, which will introduce Pint of Science to Maastricht on February 27th, 2019.

On November 28th, I went to the Societal Engagement event, organized by the University of Maastricht, representing Pint of Science Maastricht with my own stand in the “market”.

Many people showed interest in the initiative, especially because they found the idea of bringing science to the pubs cool. I also got some important contacts, such as the organizers of TEDx Maastricht Gonny Willems and Sophie Kells. Sophie works in the press office of the university and came to my stand to offer her enthusiastic support to Pint of Science Maastricht. I approached Gonny at the bar and we decided to meet in January in order to discuss collaborating on the level of training speakers for public speaking and on organizing an event with the topic “Redefining Europe” for the Pint of Science festival in May.

Last, on November 13th I went to the launch event of the Female Empowerment Maastricht initiative. This album has some amazing photos.

Photo by: Brian Megens Photography (

I took part in the Work-Life balance workshop, together with my colleague and friend Alex Emmendorfer, see us both in the picture.

Photo by: Brian Megens Photography (

That was a decent summary of November.


April 2018 – The first month

In my first week I met with my professor, Sonja Kotz, in order to kick-start the project. The agenda included:

  1. Ethics application
  2. Stimuli and sample population
  3. Training

For each of these, up to this date I have achieved:

  1. Ethics: I submitted the application on 23rd of April. The application included documents such as the information letter for subjects (including both EEG, fMRI and TMS), statement of consent form (for EEG, fMRI and TMS), debriefing form, and advertisement. The application form was submitted online through the Ethics Reveiw Committee Psychology and Neuroscience (ERCPN) of Maastricht University. The application is planned to be discussed at the next meeting of the committee, which is on May 14th. In order to prepare the documents for TMS I had a meeting with Sonja and Alexander Sack at FPN day. His assistant sent me the TMS forms that I needed to include in the ethics application; the TMS ethics application is dealt with internally in their group and there is no extra application needed with the ERCPN for this method. He also invited me to his group meeting, which is on May 8th.
  2. Stimuli and sample population: The main question was whether we run the study in Dutch or German. This decision is dependent on two factors: a) the availability of the targeted populations in Maastricht (both musicians and non-musicians) and b) the availability of high quality audio samples in German or Dutch on the public domain Librivox.
    • On the populations: I have contacted the Conservatory via email twice, but they have not responded up to this date. I have had a meeting with Niels Diesbergen, a PhD student of Elia Formisano, who has collaborated with musicians from the conservatory befoe. We will try to establish the contact with Elia’s help.
    • On the stimuli: I have been listening to various stimuli from Librivox. There is 10x more material in German than in Dutch. I contacted my collaborator in Berlin Thanos Lykartsis in order to discuss about how to model the linguistic rhythm from the auditory signal. This led to a joint meeting with Sonja, Ben Schultz (currently post doc in the BAND-LAB) and Thanos, in which we discussed how to approach the analysis of the speech signal in order to correlate it with the EEG and fMRI data. Also, we decided to employ Ben’s adaptive beat perception task in the behavioural part of the study. We then discussed how beat tracking algorithms (Ellis, 2007; Böck & Schedl, 2011; Lykartsis & Lerch, 2015) work, what are the strengths of each algorithm and how these strengths might suit well or less well to speech auditory signal than to music auditory signal. In order to avoid turning the rhythm identification task into a speaker identification task, we decided to choose stimuli from two male-voiced and two female-voiced speakers. This way, the timbre differences will not be tagged as rhythm differences by the beat tracking algorithms.
  3. Training: I have registered for two training courses to take in May.
    • On the 2nd and 9th of May I am participating in Problem-based learning (PBL) training, which is a novel method of teaching used in Maastricht University. I will be trained to become a tutor, in order to complete my teaching tasks, as included in my MSC fellowship timeline and in my contract with Maastricht University, which poses that 10% of my working hours need to be devoted to teaching.
    • On the 7th, 14th and 28th of May I am participating in fMRI security and certified user training in the Maastricht Brain Imaging Centre (M-BIC).

Last, on April 30th, last day of the month, I presented my proposed project to the BAND-LAB meeting. Here is my presentation: NERHYMUS_plan_30042018

On a slightly different note, on April 17th, I took part in the Faculty of Psychology and Neuroscience Day, in which I met many of the people of the Faculty, from PhD students to Professors. Participants were informed about the ongoing PhD projects and entertained with fun workshops on several topics such as Mindfullness and Games as interventions in teaching and learning. Some pictures:

On this event I also met Isabelle Grosch, a new colleague from the Communication Department. She brought me to contact with her colleagues and we have scheduled an interview in order to promote NERHYMUS. More on this to come in May.

April was creative and fruitful. Things are starting to roll in Maastricht. I am focused on work and I plan to keep this pace until the first deliverable in August. Then, and before starting the measurements, I will have to take a little break into the sun and the sea of Crete.