Radio silence on weblog

Dear all,

As you have noticed, not much has been posted to this weblog recently. This is most likely because most of the active bloggers of the Biomedical Group are also musicians in the ELCA band and this is the "silence before the storm", so to speak. As already announced in June’s post, the ELCA festival is upon us in (now) less than a week!

Another reason of the radio silence is due to the earthquake and successive tsunami in Japan, followed by another earthquake. Everybody held his breath when Mother Earth rumbled.

Wouter

Are Americans extraterrestial life forms?

we're not aloneTwo news items caught my attention today. The first one was the news that NASA researchers (albeit in the Journal of Cosmology) have discovered the remains of extraterrestial life forms in meteorites. The second one was that only one (1) out of almost 2000 (!) Americans fulfills all seven criteria of having a healthy human heart. Am I the only one that sees the connection?

The pressure to publish creates many victims a day

Today’s headlines of Science report that a former researcher at the renowned Massachusetts Institute of Technology has been convicted of fraud for fabricating and falsifying data. Recently a well-respected German politician copied about 50% of his PhD thesis without giving proper credits to the author(s) of the original work. He had to return his degree and resigned from the government.

plagiarism

As Editor-in-Chief of IEEE’s Transactions on Circuits and Systems-I, I receive every month a socalled "Prohibited Authors List", indicating authors that have been found guilty of plagiarism or other improper scholarly behavior and that are no longer allowed to publish in one or more IEEE journals. Unfortunately, this list is growing every month.

So, what is driving these scientists to commit fraud or plagiarism? In many cases I believe it is career pressure, as received from employers, peers, colleagues, funding agencies, or even from the researchers themselves. Of course, every scientist is responsible for his own deeds. However, the fact that the pressure may also be coming from outside means that others or other bodies can become partner in crime, too.

First of all, there is the supervisor of young PhD students, who, busy as they may be, force their young pupils to submit manuscripts to journals and conferences and inform them that the degree can only be awarded if they have at least two publications in an internationally recognized journal. There are quite a few universities that even require MSc students to have an IEEE publication before they can graduate for their MSc studies.

Second, there are the employers of (academic) staff members, who, busy as they may be, no longer seem to have the time or no longer spend enough time to properly evaluate the quality of the work conducted and thus offload their responsibility of evakuating to a number of anonymous reviewers who may or may not recommend the work be published. Often it is the number of publications that count more than their real impact.

Third, there are the funding agencies. I have evaluated a lot of project proposals over the past couple of years and one aspect to grade the applicants on is their past performance and reputation. If I have been working in the field myself, then this is a piece of cake, as I know the impact of the work conducted by my peers, at least to a certain extent. However, if you are a member of a jury that decides on, e.g., 20 project proposals of which maybe only one or two are in your field of expertise, then what do you do? I bet most people then resort to counting the number projects and publications with incomprehensible names and titles.

At Delft University of Technology, for a long time a large portion of the amount of funding professors, section heads, department heads and deans would receive from the university’s "1st money stream" depended on, indeed, the number of publications, the number of pages published and the (sometimes perceived) impact factor of the journal. I figured that if everybody at our university would only publish 50% of what he published the previous year, nothing would affect the amount of money received per faculty, department and section and this extra time could be well spent on writing better papers, performing better research and offering better education. Or on just going home on time at the end of the day for once.

Before I sign off, I would like to address young MSc and PhD students. I very well remember a case that I got involved in as editor-in-chief, in which a young, bright, PhD student abroad committed plagiarism. The plagiarism was discovered after the publication was made and, in line with procedures prescribed by the IEEE, I installed a committee to investigate the case and to decide on which sanctions should be applied. When I confronted the young author and his co-authors, of whom two were his supervisors, with the allegation made, the supervisors closed ranks immediately and blamed the PhD student for everything that had gone wrong. Despite my correspondence with the authors and expressing my viewpoint that I held also the supervisors resonsible for what had happened, in the end, the PhD degree was never awarded and the PhD student lost his appointment. I am pretty sure the professors are still there!

So my advice to everybody that is in the process of writing his first major journal paper or conference contribution is the following: please familiarize yourself with the ethical code of conduct of your organization and the publisher. For the IEEE, this code of ethical conduct can be found in IEEE’s Code of Ethics and the IEEE PSPB Operations Manual. In case of doubt, always touch base with your supervisors and/or the editor-in-chief of the journal or technical program chair of the conference you would like to submit your manuscript to. They are there to help. I know one author that contacted me well before he submitted his manuscript. By informing him of the possible consequences of his "reuse of phrases crafted by somebody else", I could prevent him from making a serious mistake by mistake and, fortunately, he still has a bright career ahead of him.

Wouter

Finally proven: blogging is good!

pointer at the word "blog"

During the short time that this blog has been up and running, I always enjoyed it a lot to read the contributions from others, as well as writing a few humble pieces myself. Today I was very happy to read that blogging is not only fun, but apparently also good for the productivity! In this paper researchers show that keeping a blog within a company actually works in a beneficial way for the productiveness of the employees.

It suddenly makes me feel a lot better about all those endless hours I spent to write a few words here… 😉

 Marijn 

Today, three Masters of Science in Electrical Engineering graduating from the Biomedical Electronics Group

Today is graduation day, at least for three members of the Biomedical Electronics Group, who will be awarded the degree of "Elektrotechnisch Ingenieur", or the Master of Science degree in Electrical Engineering as it is called in English. They are Gaurav Mishra, Hossein Tajeddin and Mark Stoopman. If you read this blog on time and if you are around, please join in the official ceremony at 13:00 hrs in lecture theater Ampere of the EWI building, or join us about 90 minutes later in the Pub to congratulate the newborn ingenieurs with their well-deserved title.

Wouter

Is darkness only all blind people can see?

Doing research on neural recording & stimulation that are dedicated to recovering human senses, a question like this may come to your mind: "between loss of hearing and vision loss, which one will make me suffer the most"

It’s a difficult question to answer…and for sure noone wants to experience it. But let’s see what famous people say…

Beethoven stated that "….for me there can be no relaxation in human society; no refined conversation, no mutual confidences. I must live quite alone and may creep into society only as often as sheer necessity demands… Such experiences almost made me despair, and I was on the point of putting an end to my life…"

Helen Keller wrote "…I am just as deaf as I’m blind. The problems of deafness are deeper and more complex, if not more important, than those of blindness. Deafness is much worse misfortune. For it means the loss of the most vital stimulus — the sound of the voice that brings language, sets thoughts astir and keeps us in the intellectual company of man." 

Three, my favourite Dutch band 😉 sings in their song ‘Way back from the Hague‘ that "Silence came over me!!!!"   …and " Darkness is all I can see."

Caraboa, the most famous Thai rock band also has a song dedicated to a blind musician called ‘Wanipok‘. In short it says (interpreted by me): ‘when my eyes are covered by darkness, my life is still illuminated… by music.’ 

For me, silence will isolate us from the society and this will lead us to a deep loneliness. Sometimes… just listening to songs, beautiful scenes can occur in our minds. Is the brain playing tricks on us? Or does it imply that losing sense of hearing is more severe than being blind and darkness is not what blind people can only see.

On March 18th, there will be the 2nd ELCA music festival in the EWI student pub Pub, at TUDelft. The Biomedical Group’s band will perform Wanipok, a cover, and many other songs. I really look forward to that 🙂

A “Moore’s law” in neural recording

Moore’s law is well-known in the microelectronics world. However, some researchers from America found something similar recently: the number of simultaneously recorded neurons has grown exponentially since the 1950s, doubling every 7 years (Fig.1). They have already begun to discuss both the computational costs and the potential for more accurate models associated with this exponential growth of the number of recorded neurons.

Fig.1 [1]

Nowadays, almost every part of the human body has been extensively analysed and studied except the nervous system, which is by far the least understood part and its disorders are the most difficult to treat. But the good news is that with the help of emerging technologies and circuit design techniques, we are able to simultaneously record more and more information from the brain. According to this new "Moore’s law", our neural data acquisition system will be able to record from all of the approximately 100 billion neurons in the human brain in 220 years.

From an analog circuit designer’s point of view, it may be a little optimistic to predict this trend, because we must always make a good trade-off among power, area, noise, speed… So it is not that easy to make your chip perfect in every aspect. However, due to the substantial progress in the amplification circuitry, embedded neural signal processors and wireless interfaces, we should believe that we can see some dramatic breakthroughs in our understanding of the nervous system and in our ability to treat its disorders in the near future.

[1] Ian H. Stevenson & Konrad P. KordingHow, Advances in neural recording affect data analysis. Nature Neuroscience, vol. 14, pp. 139-142, 2011

Yongjia

Engineers performing Brain Surgery!

The fact that we think that science is fun might not come as a surprise anymore if you have been following this blog lately. But besides fun, science can also be very tasty. Last saturday the Biomedical Group gathered around a very tasty Chinese dinner (very well prepared by a few of our students).

The dessert was very much in the spirit of our group: a brain-shaped pudding. Being familiar with brains, everybody proceeded with great enthousiasm to study it. For all of us it must have been the first brain surgery we ever did. And something tells us that it might not have been the last time!

Marijn

 

Fry in your brain, or fryin’ your brain

Yesterday, I watched a very impressive two-part television documentary made by Stephen Fry, entitled "The Secret Life of the Manic Depressive" and filmed in 2006. The documentary is about his struggle with manic depression, which he prefers to call "bipolar disorder" as this is its official name and definitively does not involve a state of continuous depression. Bipolar disorder is often treated with mood stabilizing medications and, sometimes, other psychiatric drugs. However, these are not always effective and often cause a lot of side-effects.

The second part of the documentary is about Stephen wondering whether he should consider taking drugs or other kinds of psychiatric treatment, as it looks like his symptoms are getting worse over time. So in this part he visits a few people he knows and that have also been diagnosed with bipolar and are using some form of therapy. Among them is Andy Behrman, also known as "Electroboy". According to his website www.electroboy.com, "after two unsuccessful years of experimenting with all different combinations of medication to stabilize his wild mood swings, he opted for intensive bouts of electroshock therapy," [Ed.] also known as "electroconvulsive therapy", or ECT in short, "as a last resort. He was temporarily cured."

Electroshock therapyThis, of course, brings back memories of one of the famous scenes of the movie "One flew over the cuckoo’s nest", in which Jack Nicolson rallies the patients of a mental institution together to take on the oppressive Nurse Ratched, a woman more a dictator than a nurse. He finally receives ECT to calme him down. As you can see from the picture at left, the applied ECT therapy used to be quite agressive, leading to brain convulsions and seizures or even memory loss, and has therefore been classified as "high risk" by the American Food and Drug Administration, or FDA for short.

Coincidentally, the American Psychiatric Association recently stated that the FDA should move the procedure to a medium risk state as they believe the current devices are not as brute force as their older siblings. Opponents, however, state that ECT may lead to memory loss and all sorts of other complications. If you want to decide for yourself, please check out the following YouTube movie: http://www.youtube.com/watch?v=zYl13Relzbs.

My personal opinion is that, though the doctors try to do a professional job, the applied therapy is not very patient specific and the majority of parameters are determined purely on a trial-and-error basis. Adding this to the fact that ECT is not the primary therapy, but merely serves to evoke a seizure (like you have during an epileptic insult), which is the actual therapy, makes me wonder whether there aren’t any prospects of developing a better therapy, which is better tailored to the disorder at hand and, of course, better to the patient.

Anyway, this was my sermon for the late Monday morning. If you are interested in watching "The Secret Life of the Manic Depressive", just let me know and I’ll see what I can do.

Wouter 

Rats go wireless in an analog fashion

Rat carrying wireless systemThis little image on the left shows a rat carrying a wireless system, partly mounted on his head, partly realized as a kind of a backpack. It has been developed by researchers at Harvard University in close collaboration with colleagues at California Institute of Technology and is being used for neurological research on rats in the wild. According to Nature (Febr. 25, online) the entire systems comprises "a tetrode microdrive, for chronic positioning of electrodes in the brain; an integrated circuit for high channel-count neural recordings; and a radio-frequency wireless transmitter. The device takes up to 64 analog voltage signals from neurons in the brain and muliplexes them into one signal that appears in a temporally interleaved fashion, one after the other. Then that signal is transmitted by analog FM radio to a receiver."

The article further reports that good old FM (frequency modulation) transmission has been used as it outperforms digital wireless communication on weight, power drain, throughput and distance.

So why does analog FM outperform its digital counterparts, such as FSK, QPSK, QAM and OFDM? Before answering this question it is important to realize that from a channel-capacity perspective (as defined by Shannon) there is no preference for analog modulation over digital modulation. The answer thus has to follow from practical considerations. Digital modulation implies that the information is transmitted over the wireless radio channel in a digital fashion. As all information in nature, also neural signals are analog in nature and thus, in order to prepare the neural signals for their wireless journey, they have to be converted to the digital domain by analog-to-digital conversion (ADC). This thus requires at least one ADC. Often, depending on the digital modulation type used, channel coding is performed prior to the digital modulation. As a consequence, with these additional blocks, the entire transmitter becomes more complex, which, in turn, entails a larger power consumption and, when battery-operated, a larger battery and thus a larger weight on the head or back of the rat.

Another reason why analog FM may outperform its digital counterparts lies in the frequency spectrum of the transmitted radio signal. FM produces an almost flat frequency spectrum. As a consequence, it is relatively immune to frequency-selective fading, which is good for radio communication over relative long distances. Also, FM transmission does not require a highly linear power amplifier. This is good for its power efficiency and thus for the overall energy efficiency of the transmitter.

One final remark. From the picture it looks like the rat is loaded with a transmitter that has been implemented using discrete components, rather than with a single chip (or integrated circuit, IC). Many of the blocks needed for digital transmission could be implemented with a much smaller form factor and consuming less power when realized on-chip, rendering the antenna the largest component and the largest power consumer. In such a case the choice for either analog or digital could have just as well turned upside down.

Wouter