An article this week at the Transmitter neuroscience site is entitled "What to do when traditional mechanistic approaches no longer work." The article (written by Harvard biologist Bence Ölveczky) has a strong note of frustration. It rather seems the author is not happy at all with the progress he is making in trying to explain behavior in a mechanistic manner. He says, "Many complex behaviors have stubbornly resisted mechanistic explanations." A more candid statement would have been that basically no complex human behavior has any mechanistic explanation.
The first sentence is a giveaway. He begins, "Our worldview is mechanistic, so naturally we want our explanations to be too." Yes, the neuroscience community is indeed a conformist belief community all centered around an atheist materialist worldview. That is one of the biggest reasons why its members keep making statements contrary to the observations of neuroscientists themselves, which strongly contradict "brains make minds" ideology, as the posts of this site so abundantly demonstrate.
Following the bungling neuroscientist speech custom of groundlessly claiming "representations" when no representations have been discovered, Ölveczky states, "Two regions that we had shown by lesions to make very different contributions to a behavior carried near-identical representations." The link is to an article discussing how an attempt to trace decision-making in mice to some specific brain area had failed dismally. Instead what was found (in a study implanting electrodes into an unusually large sample of mice) was roughly equal brain activity throughout the brains of mice. That article says this:
"Activity associated with choice showed up in cortical areas, in line with previous findings, but it also occurred in subcortical areas such as the hindbrain and cerebellum, challenging the notion that only a few select areas encode information about decision-making and supporting the idea that it is widespread.
'It is interesting how much choice selectivity is everywhere,' says Long Ding, research associate professor of neuroscience at the University of Pennsylvania, who was not involved in the work."
The results of the study are consistent with the idea that brains do not produce decisions. The "choice selectivity" that is "everywhere" is just the brain firing randomly all over the place, as it continuously does, regardless of whether any decision or thinking is occurring. The same continuous random firing occurs at an equally strong level even when someone is sleeping.
Referring to a length of time that is only a tenth of a second (100 milliseconds), the study's authors claim, "The animal’s choice could be decoded from neural population activity during a 100-ms time window before the first wheel-movement time in many analysed regions." The claim is groundless if it is interpreted to mean something going on in a brain prior to muscle activity. It is very well-known that muscle activity causes blips in electrode readings of the brain's activity. All that is going on is that the authors picked up a tenth of a second of muscle activity prior to the instant when some wheel starts being turned by a mouse. It is fallacious to assume that a mouse would start using its muscles at the exact tenth of a second that some wheel turned by a mouse starts turning. And if I start using my muscles to open a jar, there will surely be a tenth of second or more of my muscle activity before the jar's lid starts turning.
There is no neural correlate at all of making decisions that have no muscle movement associated with them. If you do a study of a motionless eyes-shut person connected to an EEG machine with electrodes, and tell the person to first keep a blank resting mind for 20 seconds, and then make a series of decisions in his mind during some time interval of the same length (such as what to eat and wear tomorrow), the brain wave readings for such a person will be essentially the same. In a later post I will substantiate this claim with some original research using headband technology allowing a reading of brain waves (technology that the average person can experiment with at little cost).
In the quote below, Ölveczky first suggests that attempts to create circuit-based explanations for behavior are dead ends, a blind alley. But he then comforts himself with the idea that scientists like himself can play around with "virtual animals" that exist only in a computer, and do experiments with such software creatures.
"To work our way back to a mechanistic explanation, we need to align population dynamics and function with the underlying biology. This will require accounting for how cellular mechanisms, circuit motifs and specific brain areas contribute to those dynamics and the functions they support. No experiment I can conceive of in a real animal will let us do this in a clean and comprehensive way.
Are we toast? Maybe not. The field is rapidly developing tools to create virtual animals, complete with realistic biomechanics and artificial neural networks for brains. Such critters—informed, constrained and validated by experiments in real animals—can be brought to 'life' in a physics simulation. These so-called 'digital twins' are fully observable, fully manipulable and endlessly repeatable."
We should laugh at the quotation above, which Ölveczky follows by the assertion that his lab is experimenting with virtual rats. We should ask: "What's the matter, Bence -- real life didn't give you the results you wanted, so now you've taking comfort in a virtual playground sandbox where you can program computer software rodents to get the results you want?" Bence sounds like some person whose team loses the Super Bowl, and who then seeks consolation by replaying the game, using Madden Football on his PlayStation video game machine.
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