When Neuroscience Studies Find Nothing, Press Releases Still Claim Epic Breakthroughs

There is an English expression, "Heads I win, tails you lose." It describes a situation where a game is rigged. We might use that expression to describe the situation in regard to the press releases describing neuroscience research. If perchance some neuroscience study produces some very important finding, it will be hailed in a press release claiming some grand breakthrough. But if (as is true in the overwhelming majority of cases) a neuroscience study fails to be any example of a well-designed study following good research practices, or if the study fails to provide any decent evidence of anything, then it will often still get the same kind of "praise it to the sky" press release. 

The latest evidence of this is to be found in a press release issued by a hospital in Spain. We have the grand-sounding title "Possible Foundations of Human Intelligence Observed for the First Time." The title is bunk, as are some of the claims made in the press release. 

The first sentence in the press release is this bogus claim: "A study led by Dr. Rodrigo Quian Quiroga has demonstrated how neurons in the human brain generate memories and establish narratives." It is soon followed by this equally fictional claim: "For the first time, it has been confirmed that, contrary to previous beliefs, individual neurons represent the concepts we learn, regardless of the context in which we encounter them." The claims are about a study that did nothing to establish such boasts. 

The next claim in the press release is this utterly groundless boast: 

"A study led by Dr. Rodrigo Quian Quiroga, group leader of the Neural Mechanisms of Perception and Memory Research Group at the Hospital del Mar Research Institute, has allowed scientists to observe for the first time how neurons in the human brain store memories independent of context in which they are acquired. Published in Cell Reports, the study confirms that neurons can distinguish objects or people regardless of their context, enabling the formation of higher and more abstract relationships, which constitutes the basis of human intelligence."

The rest of the press release tells us nothing to substantiate these bogus boasts. We hear about nine epilepsy patients who had microelectrodes implanted in their brains.   A general rule of thumb for experimental neuroscience studies is that any study using fewer than 15 or 20 subjects should be regarding as junk science, having used too few subjects for any decent statistical power to be produced.  The visual below illustrates the type of study group sizes that are needed in neuroscience experiments. 

In studies such as this, scientists will pick  several hundred neurons to monitor, and they will try to measure activation rates of such neurons while a subject engages in some cognitive activity. The approach is profoundly misguided. There are billions of neurons in the brain, and all neurons fire at rates of about 1 time per second or more, as many as 200 times per second. If brains stored memories or brains were responsible for producing ideas or thinking, you could never verify that by monitoring the firing rate of several hundred neurons. You might see a slightly higher firing rate in some neurons of the several hundred neurons that you selected. Since you were examining no more than a millionth of the total neurons in the brain, this would never give you a warrant for thinking that you had got lucky, and that such a tiny fraction of the brain was responsible for storing a memory or recalling a memory or having an idea. 

When we look at the scientific paper, we find that it reports things consistent with the idea that the selected neurons had no real correlation with the mental activity of the subjects. We read this:

"We observe similar single-neuron responses to the same concepts in different tasks.  Neurons do not show conjunctive coding (i.e., responding only in specific contexts or tasks)." 

It is never justified to speak of single-neuron "responses" to a concept or an experience.  A single neuron does not respond to something a  person sees or recalls or thinks about. A neuron fires continuously at a rate of about 1 time per second or more (up to 200 times per second), with random variations (as shown in the visual at the end of this post). It is always misleading to try and suggest a stimulus and response relation between a neuron firing and something someone saw or thought of or recalled.  We have in the paper ridiculous sentences such as this: "Figure 2 shows an exemplary neuron from the left hippocampus that responded to Diego Topa (an Argentinian television host) but not to the actor Jackie Chan." All that is going here is scientists tracking random activity from a noisy variable source (a human neuron), and inappropriately calling that a response. A similar thing would be going on if someone spent many hours looking at birds in his front yard, and made statements such as this: "After three hours I noticed that a sparrow in my front yard responded to my change of television channels, by leaving a tree when I  changed to Channel 7." In the Figure 2 referred to in the quote above, we actually see the neuron firing both while the person was seeing Diego Topa and Jackie Chan, with there being merely a momentary blip (a little more firing activity) while Diego Topa was seen one time. Such momentary blips (very brief increases in firing activity) happen countless times a day to every neuron. It is laughable to try to portray one of these blips as a "response" to the observer seeing a photo of someone. This is like tracking someone coughing hundreds of times a day, and claiming that one of his coughs is a "response" to an image the person sees on a TV.  

In the paper the authors confess "our main result is the absence of evidence for significant differences." The subjects were shown different visual stimuli and asked to perform different tasks as about 700 of their neurons were being monitored.  No robust evidence was found of any variation in the firing activity of these neurons that can be meaningful correlated with the activities the person engaged in. The authors refer to "the lack of context modulations and conjunctive coding described here." We should laugh hard at the authors attempt to find a trace of differential response such as their statement that one neuron once or twice fired more often when a person saw an image of one actor. Given a long tracking of random firing activity from 700 neurons in nine subjects, you would always expect to find one neuron firing once or twice more when one thing was seen than another. 

But what do you do if you are an institution press release writer, and you have a study reporting essentially that it found nothing? Egged on by your superiors to hype at all costs, and protected by the fact that such press releases have no author name, you may lie like crazy, claiming that some grand epic accomplishment was made. 

It is a scandal that very sick epilepsy patients are being lured into participating in poorly designed studies such as this, using study group sizes that are so small that they cannot be regarded as reliable evidence for anything. Very sick epilepsy patients with drug-resistant epilepsy sometimes have electrodes put into their brains to evaluate where they should have brain surgery. But the type of microelectrodes used for a study like this are a different type of electrodes, and their implanting in a patient's brain is not surgically necessary. There are serious risks associated with the implanting of microelectrodes. In this case epilepsy patients may have suffered serious unnecessary risks for the sake of a poorly designed study using too small a study group size to ever produce a robust result. Very sick patients should not be put at unnecessary risk for the sake of junk science. 

The paper claims that "electrode locations were based exclusively on clinical criteria," but that does not specifically refer to the microelectrodes implanted in the brains of these very sick patients; and that claim does not amount to any claim that the number and insertion depth of all the electrodes and microelectrodes were based exclusively on clinical criteria.

Here is a quote from a scientific paper:

"The effects of penetrating microelectrode implantation on brain tissues according to the literature data...  are as follows:

1. Disruption of the blood–brain barrier (BBB);
2. Tissue deformation;
3. Scarring of the brain tissue around the implant, i.e., gliosis 
4. Chronic inflammation after microelectrode implantation;
5. Neuronal cells loss."

Whenever this kind of Fake News is released, we should regard those  scientists who tolerate the groundless boasts about their work as being just as guilty of deceit as those who wrote the deceitful prose, because they failed to correct the misleading information. 

With a wink and a nod

Below is a visual (Figure 2) from a scientific paper that did single-cell recordings of the firings of individual neurons in monkeys. Each one of the vertical bars represents a spike in the firing rate of a neuron. There is no clear relation between the firing rate and the stimulus presented to the monkey,  The "clumpy-bursty" example was one cherry-picked to show the strongest evidence of response to the stimulus.  A visual like this makes clear that spikes or blips in the firing rate of a neuron occur randomly many times a day. It is deceptive to pick out a case where one of these blips occurs when the stimulus occurred, and to call such a blip a "response" to the stimulus. 

Studies like these can be done perfectly well with monkeys, as in this paper. It  an example of morally dubious research whenever such studies are done on human epilepsy patients, who should not be subjected to the unnecessary risks of such studies.