Birmingham ERP Boot Camp

Last week I attended a 5-day ERP Boot Camp at the University of Birmingham, and this was an incredible opportunity for me to learn from ERP experts and get specific advice for running my next ERP experiments. The workshop was led by two of the most renowned ERP researchers in the world, namely Professor Steven Luck and Dr Emily Kappenman. Luck and Kappenman are both part of the Centre for Mind and Brain at the University of California, Davis, which is one of the world’s leading centres for research into cognitive neuroscience. They are both among the set of researchers who set the publicationjen workshop blog 1 guidelines and recommendations for conducting EEG research (Keil et al. 2014), and Luck is also the developer of ERPLAB, which is a MATLAB Toolbox designed specifically for ERP data analysis. Moreover, Luck is the author of the authoritative book entitled An Introduction to the Event-Related Potential Technique. Before attending the ERP Boot Camp, most of the knowledge that I had about ERPs came from this book. Therefore, I am extremely grateful that I have had this opportunity to learn from the authorities in the field, especially since Luck and Kappenman bring the ERP Boot Camp to the University of Birmingham just once every three years.

There were two parts to the ERP Boot Camp: 2.5 days of lectures covering the theoretical aspects of ERP research (led by Steven Luck), and 2.5 days of practical workshops which involved demonstrations of the main data acquisition and analysis steps, followed by independent data analysis work using ERPLAB (led by Emily Kappenman). Day 1 of the Boot Camp provided an overview of different experimental paradigms and different ERP components, which are defined as voltage changes that reflect a particular neural or psychological process (e.g. the N400 component reflects the processing of meaning and the P600 component reflects the processing of structure). Most of the electrical activity in the brain that can be detected by scalp electrodes comes from the surface of the cortex but, in the lecture on ERP components, I was amazed to find out that there are some ERP components that actually reflect brain stem activity. These components are known as auditory brainstem responses. I also learnt about how individual differences between participants are typically the result of differences in cortical folding and differences in skull thickness, rather than reflecting any functional differences, and I learnt how ERP components from one domain such as language can be used to illuminate psychological processes in other domains such as memory. From this first day at the Boot Camp, I started to gain a much deeper conceptual understanding of the theoretical basis of ERP research, causing me to think of questions that hadn’t even occurred to me before.

Day 2 of the Boot Camp covered the principles of electricity and magnetism, the practical steps involved in processing an EEG dataset, and the most effective ways of circumventing and minimizing the problems that are inevitably faced by all ERP researchers. On this day I also learnt the importance of taking ERP measurements from difference waves rather than from the raw ERP waveforms. This is invaluable knowledge to have when analysing the data from my next experiments. In addition, I gained some concrete advice on stimulus presentation which I will take into account when editing my stimuli.

On day 3 of the Boot Camp, we were shown examples of ‘bad’ experimental designs and we were asked to identify the factors that made them problematic. Similarly, we discussed how to identify problematic results just by looking at the waveforms. These was really useful exercises in helping me to critically evaluate ERP studies, which will be useful both when reading published articles and when thinking about my own experimental design.

From the outset of the Boot Camp, we were encouraged to ask questions at any time, andJen workshop blog 2 this was particularly useful when it came to the practical sessions as we were able to use our own data and ask specific questions relating to our own experiments. I came prepared with questions that I had wanted to know the answers to for a long time, as well as additional questions that I had thought of throughout the Boot Camp, and I was given clear answers to every one of these questions.

Furthermore, as well as acquiring both theoretical and practical knowledge from the scheduled lectures and workshops, I also gained a lot from talking to the other ERP researchers who were attending the Boot Camp. A large proportion of attendees focused on language as their main research area, while others focused on clinical psychology or other areas of psychology such as memory or perception. I found it really interesting to hear the differences of opinion between those who were primarily linguists and those who were primarily psychologists. For instance, when discussing the word-by-word presentation of sentences in ERP experiments, the psychologists stated that each word should immediately replace the previous word, whereas the linguists concluded that it is best to present a blank white screen between each word. Conversations such as this made it very apparent that many of the aspects of ERP research are not standardised, and so it is up to the researcher to decide what is best for their experiment based on what is known about ERPs and what is conventional in their particular area of research.

Attending this ERP Boot Camp was a fantastic opportunity to learn from some of the best ERP researchers in the world. I now have a much more thorough understanding of the theoretical basis of ERP research, and I have an extensive list of practical suggestions that I can apply to my next experiments. I thoroughly enjoyed every aspect of the workshop and I am very grateful to CASS for funding the trip.

Participants needed for psycholinguistic experiment!

My PhD research combines methods from corpus linguistics and psychology in order to find out more about how language is processed in the brain. The method that I use from psychology is known as electroencephalography (EEG), and this involves placing electrodes across a participant’s scalp in order to detect some of the electrical activity of the brain. More specifically, I use the event-related potential (ERP) technique, which involves measuring the electrical activity of the brain in response to particular stimuli. When I carried out my pilot study earlier this year, this was the first time the EEG/ERP method had been used in the Department of Linguistics and Language, making it a really exciting project to get involved with.

Having completed my pilot study and obtained some really interesting results, I have refined my methods and hypotheses and I am now ready to recruit participants for my next two experiments. For one experiment which will take place in late August, I am looking for 16 native speakers of Mandarin Chinese; for another experiment which will take place in October, I am looking for 16 native speakers of English. I would really appreciate hearing from anyone who is interested in taking part! The whole procedure takes about 1 hour; it takes about 20-30 minutes for me to attach all of the electrodes, and the experiment itself takes an additional 20-30 minutes.

If you do decide to take part, you will wear a headcap containing 64 plastic electrode holders which the electrodes are clipped into, as well as 6 electrodes around your eyes and 2 electrodes behind your ears. The electrodes make contact with your skin via a conductive gel which enables some of the electrical signals in your brain to propagate to the electrode wires and into the AD-box, where the electrical signal is amplified and converted from analog to digital format. The amplified signals are then transmitted to the USB2 receiver via a fibre-optic cable, before being relayed onto the data acquisition computer where your brainwaves can be viewed as a continuous waveform. Before starting the experiment, I will ask you to blink, clench your teeth, and move your head from left to right so that you can see how these movements affect the observed waveform.

jen expermient

The experiment itself involves reading real language data that has been extracted from the British National Corpus. This consists of sentences which are presented word-by-word on a computer screen. After reading each sentence, you will be asked to respond to a true/false statement based on the sentence that you have just read.

Before conducting my pilot study, I carried out a number of test-runs on other postgraduate students and each one of them found it to be a really interesting experience. For instance, Gillian Smith, another PhD research student in CASS, agreed to take part in one of my test-runs and here she describes her experience as a participant:

“Getting to be involved in Jen’s experiment was a great opportunity! Having never participated in such a study before, I found the whole process (which Jen explained extremely well) very interesting. I particularly enjoyed being able to look at my brainwaves after, which is something I have never experienced. Likewise, having electrodes on my head was a lovely novelty.”

gill jen experiment


I would really like to hear from any native speakers of Mandarin Chinese or native speakers of English who would be interested in taking part in one of these experiments. Please email j.j.hughes(Replace this parenthesis with the @ sign)lancaster.ac.uk to express interest and to receive more information.

Participants needed for EEG experiment!

For my PhD I am trying to find out how language is processed in the brain by combining methods from corpus linguistics and psycholinguistics. Specifically, I have extracted real language data from the British National Corpus and modified this data so that it can be presented to participants in an electroencephalography (EEG) experiment. In EEG experiments, electrodes are placed on a participant’s head and these electrodes detect some of the electrical activity that occurs in the participant’s brain in response to particular stimuli. EEG experiments are frequently conducted in Lancaster’s Psychology Department but they have not yet been conducted in the Department of Linguistics and English Language, so it’s really exciting to try out this method which is new to the department.

When conducting an EEG experiment, I start by taking head measurements and then placing a headcap on the participant’s head. This headcap contains 64 electrode holders which I fill with conductive gel before placing an electrode into each one. I also attach some additional electrodes behind the ears and around the eyes. Once all of the electrodes are in place, the stimuli is displayed to the participant on a computer screen. This stimuli consists of sentences that are presented word-by-word, as well as true/false statements that are presented as whole sentences. Participants just need to read the word-by-word sentences and respond to the true/false statement by pressing either the ‘T’ or the ‘F’ key on the keyboard. While they’re doing this, the electrodes detect some of the electrical activity that is happening in the brain, and this information is sent to another computer which displays the electrical activity as a continuous waveform. The setup of the experiment can be seen in the diagram below.

Jen experiment

 

 

 

 

 

Throughout my PhD I will be conducting a series of experiments starting with a pilot study. In my pilot study, the experiment itself lasts for just 10 minutes but it can take me up to an hour to attach all of the electrodes. This preparation time should decrease as I carry it out on more and more participants.

I have already conducted several practice runs of my experiment with other postgraduate students. For example, Gillian Smith, another PhD research student in CASS, agreed to take part in one of my practice runs and here she describes her experience as a participant:

Jen experiment Gill

 

“Getting to be involved in Jen’s experiment was a great opportunity! Having never participated in such a study before, I found the whole process (which Jen explained extremely well) very interesting. I particularly enjoyed being able to look at my brainwaves after, which is something I have never experienced. Likewise, having electrodes on my head was a lovely novelty.”

 

 

I am currently looking for 15 native speakers of English to take part in my pilot study.

If you are interested in taking part in this experiment please email j.j.hughes(Replace this parenthesis with the @ sign)lancaster.ac.uk for more information.