Consciousness causes higher entropy compared to unconscious states in the human brain

[uncool]

OK, I looked at the original article (in arxiv.org) and there is even less there than I expected. MANY basic problems in this article.

First, there were only *9* people tested. There is NOTHING that can be done statistically with a study of 9 people. I could stop there, but the problems keep going.

They determined if different channels on EEGs were 'connected' by whether the correlations met a certain 'threshold', but that threshold was never given explicitly. Then, if the values exceeded that threshold, they were set to 1 and otherwise set to 0.

Next, they use an *incredibly* simplistic model for the 'complexity', essentially that of a binomial distribution. The problem is that such a distribution has only one parameter (in this case the number of correlated channels) and the characteristics are such that 'more entropy' simply means 'more connections active' (unless more than half of the channels are correlated).

So, their ultimate 'result' is that there are more active connections when someone is awake than when they are asleep or in a coma.

Since they use Shannon entropy instead of thermodynamic entropy, and since their actual model is so simplistic, the claim that entropy 'causes higher consciousness' is just not supported by this study.

TL;DR: Their experiment uses too few people, is based on a model that simply states people that are awake have more active brains.

The connection to entropy is, truthfully, completely bogus.

Your criticism is reasonably easily shown as bunk for the following reasons:

• Contrary to your claim, the paper didn't mention that "entropy causes higher consciousness". In fact, the word "cause" can't be found in the paper!
  

• Additionally, contrary to your claim, the threshold was explicitly mentioned.
  
  
• Reference-A, Quote from paper, describing threshold: "We tried another less prejudiced method, using surrogates of the original signals, and then computing the average synchrony index among the surrogate population (10 phase-randomised surrogates per original channel/signal)."
  

• Biological human brains are generally predicted to behave in quite similar manners, so that 9 people were  examined, does not suddenly invalidate the results.
  

• Shannon entropy does not prevent the measurement of the difference between conscious and unconscious states. (As indicated by the writers, Shannon entropy was used to circumvent the enormous values in the EEG results. It is typical in programming to use approximations or do compressions of the input space!)
  

• Reference-B, Quote from paper, describing compression rationale: "However, the estimation of C (the combinations of connections between diverse signals), is not feasible due to the large number of sensors; for example, for 35 sensors, the total possible number of pairwise connections is [1442] = 10296, then if we find in the experiment that, say, 2000 pairs are connected, the computation of [102962000] has too large numbers for numerical manipulations, as they cannot be represented as conventional floating point values in, for instance, MATLAB. To overcome this difficulty, we used the well-known Stirling approximation for large n : ln(n!) = n ln(n)˘n".
  

• Reference-C, Showing that Shannon Entropy (i.e. a compressed measurement) does not prevent comparison of entropy in systems: https://en.wikipedia.org/wiki/Entropy_in_thermodynamics_and_information_theory
  

My question to you is: 

• Why do you personally feel (contrary to evidence) that Shannon entropy measure supposedly prevents the measurement of conscious vs unconscious states in the brain, and also, don't you realize that it is typical in programming to encode approximation of dense input spaces?