One of my all time favourite bloggers, Oxford Neuroscientist Prof. Dorothy Bishop, or DeevyBee as she is known on Twitter has performed an amazing open access lecture focusing largely on the misunderstanding of neuroscience (click down to the “Emanuel Miller Lecture” to play the video). The talk is incredibly informative and digestible, even those with no understanding of neuroscience or psychology whatsoever will take a great deal away. The problem of the poor understanding of neuroscience is one of the main reasons why I started this blog, so if you like this blog then you’ll love this lecture.
Click here to download the slides.
The talk begins with a reasoned explanation of how and when we should be sceptical of neuroscience research, Bishop goes on to cite 4 key reasons why certain kinds of scientific research will inevitbaly result in false-positives:
“The four horseman of the apocalypse”
1. Maturation – People develop naturally over time.
“There seems to be an implicit assumption that the brain, because it is a physical organ is somehow not going to change unless you give it some intervention – that it is there as a static thing. This is completely untrue… as evidenced by this series of images.”
2. Practice effects – when people keep doing the same test again and again, they get better at it.
“…purely to do with the fact that you have got better at doing the test and nothing to do with your abilities… People forget that this can apply to language tests and thing like that. It also applies to some extent to the brain, often we don’t know how important this is because brain imaging is so new.. clearly if you get brain responses to novelty, that means if you do something twice – the first time round you will get different responses to the second time round when it is no longer novel”.
3. Regression to the mean – a statistical artefact of longitudinal studies that is exacerbated if you select participants on the basis of a low score on a test (for example participants with developmental difficulties). Bishop does an outstanding job of explaining the problem at about 18 minutes in to the talk.
“Regression to the mean is as inevitable as death and taxes”
Campbell and Kenny (1999) A primer on regression artefacts
4. The placebo effect. This is the obvious consideration that continues to impact poorly designed research but according to Bishop, the three issues listed above could actually be having an even greater impact than the placebo effect.
Bishop explains that a control group is vital in order to achieve valid findings, but a control group alone is not enough, we should also be asking questions such as:
- Are the groups randomly assigned – or is there some other factor at play?
- Is the control group given an alternative treatment? If not, why not?
- What causes drop out? People don’t tend to drop out at random and this can have a very big effect on results.
Weisberg, Deena Skolnick. (2008). The Seductive Allure of Neuroscience Explanations. Journal of Cognitive Neuroscience, 18 (3), 229-477 DOI: 10.1162/jocn.2008.20040
Campbell and Kenny (1999) A primer on regression artefactsFollow Simon on Twitter, Facebook, Google+, RSS, or join the mailing list.
Researchers have demonstrated the first 3D control of a robotic arm from electrodes implanted directly in the brain. This technology has been tested before in monkeys but this is the first time the technology has been successfully trialled in humans. Until now, human brain computer interfaces (BCI) have been limited to two dimensions. This is clearly a huge step forward for BCI technology however it will likely be a very long time before we see this technology affecting our lives. Methods which do not require electrodes to be attached directly to the brain have to use much weaker signals as the brain waves must travel through the skull and the tissue above the brain. Due to the cost of invasive brain procedures and the associated risks, it is therefore unlikely that this method will be used for anything but the most extreme cases of paralysis.
Hochberg, L., Bacher, D., Jarosiewicz, B., Masse, N., Simeral, J., Vogel, J., Haddadin, S., Liu, J., Cash, S., van der Smagt, P., & Donoghue, J. (2012). Reach and grasp by people with tetraplegia using a neurally controlled robotic arm Nature, 485 (7398), 372-375 DOI: 10.1038/nature11076
Synaesthesia is a peculiar neurological condition in which the senses are interlinked in unusual and mind bending ways, the genuineness of the condition has been verified by concrete clinical studies. Letters, sound and taste can have colours, days of the week can have personalities, textures can have smells, the list goes on (see below). It’s a phenomenon that’s easy to describe in simple terms but difficult to fully appreciate. It was only recently discovered that the prevalence of synaesthesia may by 88 times higher than previously assumed. Brain imaging experiments have helped shed light on the cause, with the prevailing explanation of synaesthesia being that we are all born with the neural connections interlinking the different sensory areas of our brain, however in normal development most of these connections are pruned whereas synaesthetes maintain the connections. The animation below, made by a student is the best visual depiction of the phenomenon I’ve seen to date.
The different factors that synaesthesia may affect are:
- Days of the week
- Months of the year
- Food stuffs
- Sounds, tones and music
- Personal associations – e.g. mother-smell
Simner J, Mulvenna C, Sagiv N, Tsakanikos E, Witherby SA, Fraser C, Scott K, & Ward J (2006). Synaesthesia: the prevalence of atypical cross-modal experiences. Perception, 35 (8), 1024-33 PMID: 17076063 (PDF)Follow Simon on Twitter, Facebook, Google+, RSS, or join the mailing list.
A paper published today in the journal Neuron describes how the mainstream media (specifically the Daily Telegraph, Times, Daily Mail, Sun, Mirror and the Guardian) have tackled the topic of neuroscience over the past decade. The paper is a damning indictment of how the press use neuroscience as a tool with which to “portray themselves as dispassionate” whilst preaching their trademark prejudices. The paper describes how the Telegraph used research to wrongly “assert that productive female participation in both the labor market and family life is neurobiologically impossible”, while the Daily Mail miscellaneously linked “women to irrationality” (amongst countless other crimes) and the Times absurdly squealed “are gays dopamine junkies?”. The paper lists a labyrinth of logical fallacies which the media use to misrepresent neuroscience, repeatedly highlighting a tendency for:
“overextensions of research, with implications drawn far outside the original research context. This overextrapolation of research was not limited to idle speculation but sometimes extended to calls for concrete applications.”
The paper assessed the contents of nearly 3,000 articles involving neuroscience over the past decade to see which topics came up most. It’s not hard to see how the data is skewed by the media’s recent obsessions such as fish oil and narcotics. I’ve tossed the figures in to Manyeyes to make the information a little easier to digest:
Subjects Addressed within Media Coverage of Neuroscience
The paper concludes that the media has used neuroscience research “applied out of context to create dramatic headlines, push thinly disguised ideological arguments, or support particular policy agendas”. Fighting this tidal wave is the precise reason that I started this blog. For regular readers none of this will come as a surprise. I’ve previously described how the media has misrepresented everything from social networking and love to vaccination, drugs, and cognitive enhancement. I must admit that I find this issue so distressing that I have been left with the unfortunate tenancy to generally rant on the topic uncontrollably.
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This week two new brain computer interface (BCI) based products have hit the headlines, one is a hoax. I’ve placed the adverts for both below, see if you can figure out which one is a real project.
Project Black Mirror
The developers of “project black mirror” claim to have developed a BCI that can control an iphone using Siri.
The developers of “Neurowear” claim to have developed a pair of wearable rabbit ears containing a BCI that moves based on your mood.
But, can you tell which one is an elaborate hoax?
(Watch the videos, check out their websites but don’t scroll down until you’ve made your guess.)
Believe it or not, it turns out that the project that is a hoax is actually the mobile phone device “project black mirror“. This is clear for a number of reasons:
1. EEG can not yet be deciphered anywhere near the extent necessary to achieve a wide range of commands based simply on imagined words. At the moment it is only possible to assign commands based on cues such as our emotions or imagined movements of different parts of the body. Even then, there is a very long way to go before we can achieve significantly more commands than can be counted on one hand.
2. On the “project black mirror” page the group make the blunder of describing the device as an ECG instead of an EEG. An ECG is an electrocardiogram which measures activity from the heart while an EEG is an Electroencephalograph which measures activity from the brain, by definition, a necessary component in any BCI (the brain, that is).
3. On the “project black mirror” page the group describe the device as measuring signals in the range of 0-5v. EEG signals are approximately one millionth of that range! (“microvolts” not “volts”.)
4. The chip board in the “project black mirror” video isn’t properly attached.
5. In the “project black mirror” video, on the laptop screen there is an animation of the matrix code, presumably instead of an EEG output.
As @Interaxon has pointed out, this is a rather sad trick to play because it devalues the work being done by genuine BCI researchers and raises expectations to an unrealistic level. That said, progress is being made. Only this week a breakthrough study was published in the Lancet that demonstrated using EEG that 19% of patients diagnosed with being in a vegative state could respond using BCI.
“Three (19%) of 16 patients could repeatedly and reliably generate appropriate EEG responses to two distinct commands, despite being behaviourally entirely unresponsive (classifi cation accuracy 61–78%)”
(Cruse et, al, 2011) [Open access PDF via The Lancet]
This is a major step forward, demonstrating clinically that there really is potential for us to communicate using the many different BCI packages in development around the world with those that currently have no way of communicating whatsoever. This really is a noble goal and one that we are, right now, witnessing being achieved for the first time. Conversely, the “Project Black Mirror” video appears to be attempting to capitalise on this by applying to crowd-fund their “project” using Kickstarter. This is at best a poor thought out hoax and at worst a blundering attempt to commit a major fraud.
Now, there is one question left to answer and that is…
“What about the BCI rabbit ears?”
Well, it seems that this project may well indeed be genuine. The concept itself is certainly scientifically grounded and empirically demonstrated (Coan, et al. 2004) [Open access PDF]. As for the product, well if there is someone bonkers enough to create it then there would be no reason why it would not be technically possible. And that, it would appear, there is.
NB: This is not an endorsement of the “neurowear” product. I have seen no published data and the apparent use of one electrode suggests the device would be vulnerable to confounding facial movements (See my critical post on the Emotiv’). That said, they certainly aren’t the first group to come up with an attempted wacky implementation of BCI and they certainly won’t be the last.
Damian Cruse, Srivas Chennu, Camille Chatelle, Tristan A Bekinschtein, Davinia Fernández-Espejo, John D Pickard, Steven Laureys, Adrian M Owen (2011). Bedside detection of awareness in the vegetative state: a cohort study The Lancet : 10.1016/S0140-6736(11)61224-5
Coan, J., & Allen, J. (2004). Frontal EEG asymmetry as a moderator and mediator of emotion Biological Psychology, 67 (1-2), 7-50 DOI: 10.1016/j.biopsycho.2004.03.002
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