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Comments on 'mapping the Mind' by Rita Carter

Preface

This text contains comments on Mapping The Mind(Rita Carter, 2000, paperback edition, Orion Books, London, 075380190). I wouldn't bother to write anything about this book, but Rita Carter actually e-mailed me complaining that my comments in my bit about garbage 'popular science' books were not based on any example.

The comments are only on the most obvious distortions and confabulation in the first three chapters, as I think this is already much more attention that the book deserve. It should be much more than enough to convince you to ignore this book altogether.

I would expect many of the readers to find it impossible to believe that a book that contains such confabulations would be published, and hence refuse to believe that they are confabulations (this is the typical blatant nonsense effect). If you are one of these readers, pick up at random one of the points that I raise, and check it with an expert on brain anatomy or clinical neuroscience.

0. Introduction

[0.1] The third sentence of the book reads (p.1):
Now, however, new imaging techniques make the internal world of the mind visible, much as X-rays reveal our bones.
This is simply false, for two reasons:
Resolution
The amount of details in brain imaging is similar to the amount of data in an X-rays picture of the bones. However, the phenomena under investigation, i.e. the mind and its mechanisms in the brain, are many orders of magnitude more complex, so the same amount of information tell us much less. X-rays can be made to give higher resolution, but that is not true for current brain imaging techniques, because they are all based on observing processes that are inherently low resolution. In particular, The 3D techniques, fMRI and PET, observe changes in blood flow, which have a very gross resolution.
reproducibility
Even more serious for brain imaging, the 3D techniques, when applied to the cortex (the main thinking part) cannot produce reproducible results (see here for a paper showing this, and here for further discussion). The results of such imaging tend to agree with the gross areas that were already identified in the 19th century (the sensory-motor areas and Wernicke and Broca areas), but higher resolution results are not replicable. Thus they are essentially noise, though it is possible that some of them are idiosyncratic to the individuals being imaged.

[0.2] Rita Carter regard reproducibility with contempt. On p.4 she says:
Most of what you will read is actually more complicated than I might make it appear, and some of it will almost certainly turn out to be wrong. This is because many of the findings are too new to have been replicated.
[0.3] So why writes a book for lay people based on findings that haven't been replicated? Carter would probably say to make sure that the book is up to date. The real answer is that without relying on unreplicated results there will not be a book, as most of the book relies on irreproducible results from brain imaging and other studies (in addition to evidence-free confabulations).

[0.4] On p.1, end of the third paragraph, Carter writes:

Similarly, it is now possible to locate and observe the mechanics of rage, violence and misperception, and even to detect the physical signs of complex qualities of mind like kindness, humour, heartlessness, gregariousness, altruism, mother-love and self-awareness.
[0.5] This sentence is a blatant lie. We cannot observe the mechanics of rage, violence and misperception and hardly locate some of them, and we cannot see the physical signs of any of kindness, humour, heartlessness, gergariousness, altruism, mother-love or self-awareness. All the cases where these processes has been "observed" are either irreproducible results or overinterpretations of the data, and in most of the cases both.

[0.6] It may be that Carter intends to demonstrate that claims in the rest of the book, but she doesn't make this clear.

1. Chapter One

[1.1] On page 10 , Carter presents a case of an epileptic in whom passing a current through some part of her brain causes her to become amused. She then says (p.10) :
The surgeons seemed to have come across a part of the brain that creates amusement, however unpromising the circumstances.
This nonsense demonstrates the two main problems with the book: overinterpretation and contempt for reproducibility:
Overinterpretation
The current in this region causes the patient to feel amusement, but that doesn't tell us it is a part that creates amusement. For example, if we tickle somebody's foot and they become amused, we are not going to claim that their foot creates amusement. The only difference between the two cases is that the epileptic was not aware of the current in her brain.
contempt for reproducibility.
Obviously, this case is irreproducible across individuals. As Carter herself says, the procedure that was used is quite routinely applied, yet in general it doesn't show an "amusement area", not in the same place as in this patient or anywhere else. Thus it is not a general feature of the brain, but an idiosyncratic feature of this specific patient.
[1.2] This example also demonstrates other features of Carter's writing:

[1.3] of course, in this case an alert reader can see the problem both with the overinterpretation and the lack of reproducibility across individuals. Carter, however, writes to lay people that do not expect to have to critically assess statements that the author makes, and hence will mostly follow her nonsense ideas without thinking.

[1.4] On pages 12-13 Carter discuses areas that are "associated with religion." After a mentioning "neurologists at the University of California San Diego" without a reference (top of p.13), which I don't know what is supposed to refer to, she refers to Persinger's work. She doesn't tell the reader that Persinger is quite unique both in his ideas and in his actual results, and that even he regards what he sees more like delusions, and the main thrust of his work is to explain UFO cases. She doesn't even quote his conclusions, and instead quotes from the "Independence on Sunday' (a weekend version of a daily newspaper), what is presumably a quote from Persinger (P.13). This quote describes an anecdote which is obviously irreproducible. All this does not stop Carter in her tracks, and next she writes(p.13):

The fact that we seem to have a religious hot-spot wired into our brains does not necessarily prove that the spiritual dimension is merely a product of a particular flurry of electrical activity.
[1.5] Here, Carter uses the trick of lying by implication: She doesn't say: "that establishes that we have a religious hot-spot" (which is obviously nonsense), and instead discusses other aspect of the question as if this fact has already been clearly established. This way make it harder for the reader to spot the nonsense.

[1.6] Two interesting point about "religious hot-spot" discussion are that Carter makes quite a blatant use of the "lying by implication" trick, and that after making the quite grandiose claim of a "religious hot-spot wired into our brains", she leaves the subject and does not return to it.

[1.7] On page 7 Carter says:

New neural connections are made with every incoming sensation and old ones disappear as memories fade.
This statement is so trivially false that it is hard to believe that it is actually supposed to mean what it says. It seems to me most likely that "neural connections" don't actually mean here synapses, but something else, but it is not obvious what. Nevertheless, a lay person cannot know how wrong this statement is, and therefore will understand from it that neural connections, in the sense of synapses, are created with every incoming sensation.

[1.8] At the bottom of page 15, Carter says:

Part of the brain's internal environment is a ceaseless pressure to seek out new stimuli. This greed for information is one of the fundamental properties of the brain and it is reflected in our most basic reactions.
Apart from the bizarre language (what is "internal environment"?), this statement is not unreasonable. However, except in this paragraph, Carter completely ignores the question of curiosity, even though it is "one of the fundamental properties of the brain".

[1.9] On page 16 Carter says:

Computer simulations of neural networks show that the simplest network can develop phenomenal complexity in a short time if it is programmed to replicate patterns that are beneficial to its survival and junk those that aren't. Similarly, brain activity evolves in the individual.
The first sentence (about computer neural networks) is a typical overinterpretation common in the artificial networks field. The last sentence (that the brain does the same) is simply false. There isn't anything that could be remotely considered as evidence for it, and because of the stochastic connectivity of the cortex, it is clearly false.

[1.10] An interesting point about this discussion is that Carter does not refer to the proponents of "neural Darwinism" (Edelman and Calvin), even though they are the only reason this nonsense has any standing. The other interesting point is that after presenting this as the mechanism of learning, she ignores it in the rest of the book.

[1.11] On page 17 Carter says:

The pattern of brain activation during, say, a word retrieval task is usually similar enough among a dozen or so participants who typically take part in such studies for their scans to be overlaid and still show a clear pattern.
That is a blatant lie. Overlaying patterns of the participants will come out as an indiscernible jumble. The reason that such studies come with "clear results" is that they use quite complex software which eliminates all the "noise", including any disagreements between different brains. As I show in the discussion of averaging in imaging, even simple averaging applied to brains that are totally randomly related can generate "significant" results. Since brains are not totally randomly related, and the software that imagers use is much more sophisticated, they don't have a problem to generate "clear results" out of what is essentially noise. The fact that they cannot generate reproducible results shows that this is what they do.

[1.12] In the case of word retrieval the point is specifically demonstrated by one of the few studies that actually tried to reproduce results across different laboratories ( Poline J-B, Vandenberghe R, Holmes AP, Friston KJ, Frackowiak RSJ. Reproducibility of PET activation studies: lessons from a multi-center European experiment. NeuroImage 4, 34 54 (1996)). The results in their figure 2 are already averaged across individuals in each center, so individual brain differences have already been filtered out, yet the patterns don't match at all.

[1.13] On pages 17-22 Carter perform her greatest confabulation. She starts on the first line of page 17, discussing the neurones in the brain of a new born baby:

These neurones are not mature, however. many of their axons are as yet unsheathed by myelin - the insulation that allows signals to pass along them - and the connections between them are sparse.
The claim that the myelin "allows signals to pass" is a simple lie. Myelin speeds them up, and maybe increase the reliability, but signals pass in unmyelinated axons too. This is another of "lying by implication", as Carter does not explicitly states that signals cannot pass through unmyelinated axons, it is just implied strongly.

[1.14] The "sparseness" of the connections is also very misleading. The connectivity in the adult cortex is also sparse, as each neuron is in contact only with a very small fraction of the neurons in the cortex. However, this small fraction is still a large number (typically thousands). In the baby brain, there are much less connections, but still each neuron is connected with many others (probably hundreds). Next Carter writes (p.18):

Hence large areas of the brain, and particular the cerebral cortex, are not functioning.
[1.15] That is a blatant lie, and quite a ridiculous one. The cerebral cortex is clearly active at birth. Carter seems to base this nonsense on the claim that PET studies don't show activity in the cortex, but she doesn't actually say that. The next sentence reads:
PET studies of new-born brains show the active areas those associated with bodily regulation (the brainstem), sensation (thalamus) and movement (deep cerebellum).
i.e. she doesn't actually make the claim that PET studies show that the cerebral cortex is inactive, and let the reader deduce it. (It is quite possible that PET cannot detect signals in baby's cortex, due to some limitation of the method). She gives a reference to a monograph by J.M. Tanner (which I haven't read) from 1989. In principle, it is possible that Carter based her confabulation on something that Tanner wrote, but I doubt it because a search on the net suggests that Tanner is an anthropolgist with interest in human growth, but not in neuroscience.

[1.16] The idea is developed further on p.21, where Carter associates psychological developments with activation of areas in the cortex, e.g.

The frontal lobes first kick in at about six months, bringing the first glimmering of cognition.
and
The language areas become active about eighteen months after birth.
All these associations are total confabulations, as all the areas of the cortex are active at birth.

[1.17] It should be noted that this confabulations are more than just distortion of the process of development. The (fabricated) neat association between activation of areas and psychological development is obviously a very strong evidence for the association of function to the areas, and most of readers will figure this out. As a result, even those that don't "learn" about development from reading this part, will be still left with the impression that there is a very strong evidence for the association between areas and function, even though all this "evidence" is a confabulation.

2. Chapter Two

[2.1] On pages 51-53 Carter presents a description of the way humour works based on interactions between the hemi-spheres, which is evidence free. I don't know if the claim that the right-brain lesion patient is more likely to pick the literal end for a joke (p.52) is based on evidence or a confabulation, but any cognitive deterioration would in general lead to simpler responses, so even if it is true it shows nothing. The idea that left-brain patient will choose (a) is clearly an invention from the way the text is written.

[2.2] After discussing symptoms in patients with split brains, Carter starts to "apply" the results to healthy people. On page 58 she claims

Odd remarks that just slip out, feeling we can't explain, silly errors like mistaking one object for another, are traditionally seen as evidence of deep inner conflicts. In fact, many of these may be caused by faulty or incomplete inter-hemispheric communication.
This hypothesis is not based on any evidence. maybe it is supposed to be based on the evidence from the data split-brain patients, but this data doesn't tell us what happens in a healthy brain. It should be noted that Carter uses here the trick of a strawman alternative, where an unlikely possibility ("deep inner conflicts" here) is presented as an alternative, here the only one. However, since all we are talking here is a temporary failure of the system, there is no need to look for deep explanation, as there are infinite ways in which a complex system like the brain can fail.

[2.3] At least in this sentence Carter qualifies the statement by using the word "may", and she does it in several of the other baseless ideas on pages 58-9. However, she doesn't qualify it in the caption of the picture at the top of page 59, where she says:

The left hemisphere sees only the lines - the right sees the dog.
Again, A statement which is not based on any evidence. And in the next page, all doubts disappear (p. 60):
The left/right hemisphere split often shows up in our reactions to art: 'I like it but I don't know why' is not necessarily a philistine reaction - it demonstrates only that the work is being appreciated by the right brain rather than analysed by the left.
Another evidence-free statement (and using again the strawman alternative trick (philistine reaction)).

3. Chapter three

[3.1] On pages 84-86, Carter presents her theory of how the brain make sure that "body parts do whatever is required to find food, sex, security and other vital requirements." The substantial part of this theory is that the second step requires an action. On p.85 she writes:

Note - the action is the thing. Not just the food, or the sex, or being at home.
(Italics in the source).
This ridiculous statement (does Carter really think that people don't enjoy 'just sex'?) presents the essential role of action as if it is a well established fact, even though that is Carter's invention without relation to any evidence. It is possible that the next sentence is supposed to be supporting evidence:
Having nutrients pumped into the blood keeps you alive but it does not give the same pleasure as a meal that has to be prepared, served, chewed and swallowed.
That is clear nonsense: preparing and serving the food is clearly not essential part of enjoying it for most of people, and chewing and swallowing are enjoyable because the way they stimulate the taste buds, smell receptors and touch receptors in the mouth and throat.

[3.2] At the bottom of page 86 Carter starts to discuss the putamen. First she writes:

The twitches are fragments of skills - each a tiny, degraded echo of once purposeful movement - that are triggered into existence by bursts of activity in an area of the unconscious brain called putamen.
These assertions, which are presented as facts, are evidence-free speculation. There is no evidence that the twitches are in general "fragments of skills", though in some cases they may be. And there is no evidence that they happen because of bursts of activity in the putamen.

[3.3] Very little is known about the role of the putamen, except that it one of the parts of the brain that are most affected in Huntingdon disease. There are some speculations on its rule in Tourette's syndrome, but no robust evidence. Carter, however, has her own ideas (p.85-86):

Its function is to look after automatic movements - those that have been learned by repetition - and keep them flowing so the conscious brain can get on with the grander business of deciding how to direct those movement and learning new ones. Pedalling a bike (providing the rider is experienced), for example, is controlled by the putamen, while the movements needed to execute a new and complicated dance, say, would be controlled by different brain areas.
This is a total confabulation, and (in contrast to the speculations in [3.2]) is clearly false. All volitional movements, including highly learned ones liking riding pedalling bicycle (what is referred to as "automatic") are controlled by the motor areas of the cortex, via the brain stem, with some involvement of the Cerebellum which is essential for accurate and smooth movement. At most, the putamen has some modulating effect on the cortex, but it certainly does not control pedalling a bike.

[3.4] At that point Carter does not mention the motor cortex at all. In the picture on page 88 the motor cortex does appear, interacting with the putamen, but the figure layout suggests that it is the putamen that is in more direct contact with the legs. In the caption (p.89), Carter first reiterates the lie that the putamen is in control, then follows it with a somewhat confused and evidence-free description of how it controls movements via the cortex, and repeats the speculation that overactive putamen causes Tourette's syndrome. Carter returns to the putamen in the pictures on pages 264 and 266, claiming that procedural memories are stored in it (clear nonsense, these are obviously is in the cortex), and mentions it again on 282.

[3.5] On pages 91-92 Carter repeats the same kind of evidence free speculations about the putamen in Tourette's syndrome, this time about the caudate nucleus and Obsessive Compulsive Disorder (OCD). She writes (pp. 91-92):

But in this case the memories are not personal ones picked up during the person's lifetime but those that are built into the species as instincts. The instinct to keep clean, to check the environment constantly for signs of anything untoward; the need to keep order and balance - all these have a basis in survival.
This is totally evidence-free, and clear nonsense. Humans clearly don't have an instinct to keep clean, and children have to be taught to do it. Checking the environment and keeping order and balance are less obvious. However, OCD also involve many other kinds of behaviours, some of which Carter mentioned in the preceding pages, and many of these are clearly not instincts.

[3.6] Carter than writes later on the same page (p.92):

In a normal brain the caudate nucleus looks after certain aspects of automatic thinking just as the putamen looks after automatic movements. The caudate nucleus is the part of the brain that automatically prompts you to wash when you are dirty; that reminds you to check the doors before you leave the house; and that alerts you to and focuses your attention on anything that is out of order.
All of this is evidence-free confabulation, and the second sentence is total nonsense.

[3.7] Carter then goes on to describe an experiment with monkeys and some scanning experiments on OCD patients. She may have meant these to be the evidence for this nonsense, but even if these studies will prove reproducible, they don't support her confabulations at all.

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Yehouda Harpaz
yh@maldoo.com
26Jan2001
http://human-brain.org/