I consider “neuroanatomy” to be the physical configuration of matter in the brain that instantiates brain function, behavior or properties. Any changes (not involving xenobiotic effects, drugs, trauma) in brain function, behavior or properties can only occur via neurodevelopment and is due to the changes in neuroanatomy that neurodevelopment produces.

The idea that there can be a purely genetic process in neurodevelopment is not correct. The properties of the brain are emergent properties from large ensembles of cells working together, each cell doing something different, but the large ensemble of cells instantiating the emergent behavior of the brain, thinking, memory, pattern recognition. For brain cells to work together, they must be controlled to work together and must exchange signals to synchronize their respective different behaviors. This synchronization requires signaling between cells. The genome inside one cell doesn’t “know” what the genomes inside other cells are doing unless there is communication between cells.

Hebbian remodeling is an example of a process in neurodevelopment mediated through communication between cells. The cells “wire together” as a consequence of “firing together”. The resulting neural network depends on both the genetic instructions in the cells and also the pattern(s) of signals. The patterns of signals affect the ongoing development of the neural network, so it becomes extremely complicated very quickly. This type of development is the product of many non-linear coupled interactions, so it is chaotic in a mathematical sense.

I think that the problem some people have with understanding my approach is that they are stuck in thinking of “neuroanatomy” as what you can see if you open up a brain, and there is the default idea (perhaps unconscious) that the brain “works” by having the “mind” do “stuff” with the “neuroanatomy”. My conceptualization is that there is only neuroanatomy (the physical arrangement of matter in the brain) and it is that neuroanatomy that is responsible for everything that the brain does. We don’t know or understand all of what neuroanatomy is, or how it instantiates what the brain does.

From my perspective, if all change in the properties of the brain are consequences of neurodevelopment. That includes forming memories. Memories can be formed in less than a second. Memories are instantiated by changes in the neuroanatomy of the brain (by processes we do not understand). Maternal bonding occurs very rapidly (minutes). I have no conceptual problem with face pattern recognition happening very rapidly.

If we want to understand how pattern recognition neural networks could develop, we need to figure out how cells could connect themselves together to be sensitive to a specific pattern. It is easy to see how Hebbian remodeling could produce good pattern recognition by having the network instantiate more gain from prior pattern exposure. How could a network develop pattern recognition without a pattern? Various parts of the visual system do exhibit spontaneous firing, which triggers activation which spreads out in waves. Waves of this type do have spacial and temporal information. Depending on the spacing between nerves and the wave propagation velocity, spontaneous waves could be used to generate pattern recognition of spacial frequency, timing frequency, and some other things.

I think it is quite likely that the human visual system is optimized to detect spacial frequencies that are important. This is instantiated by things like eye size, lens shape, retina cell density, minicolumn size and density, cell firing thresholds and so on. This may (probably does) include spacial frequencies found in faces.

There could be generation of pattern recognition of shapes that can be instantiated by spontaneous wave propagation. Linear waves could generate linear pattern recognition, linear waves propagating in diverse directions could program linear pattern recognition in many orientations. Circular waves propagating from random single initiation points could program circular pattern recognition. There might be pattern recognition for little circles inside a big circle. Something like that might “look” like a face to an adult researcher, but a face would not produce the highest detection signal.

How to test these? I am not sure. Maybe looking at fMRI, EEG or MEG in utero, to see what patterns of neuronal firing are occurring could be used to infer whether or not certain brain regions are active and so whether or not they have instantiated pattern recognition yet. I don’t know if fMRI has been done in utero yet. It might not work because the O2 levels in utero are very different, but then fetal hemoglobin is different too so it might.

Looking at the evoked response due to a flash of light in utero might allow an inference of spacial frequency detection, but the fMRI signal is not due to neuronal firing, it is due to differential hemodynamics. There might not be the strong correlation between fMRI and neuronal activity in utero that there is postnatally.

I take pretty strong objection to people stating that something is “genetic”, without the identification of the genes and/or DNA that is responsible. We are in the post-genomic era. If there is the claim that something is genetic, lets see the genes that are responsible. My perspective is that the people who have been claiming stuff is “genetic” are having difficulties finding the DNA that they claim is responsible.

I especially take especially strong objection to claims that brain properties are “genetic”, and especially the idea that intelligence and IQ are “genetic”. The scholarship in the genetics of IQ and intelligence field is very poor with very fundamental aspects remaining undefined (like what is intelligence and how can it be reliably measured). Intelligence is a property of a phenotype, not a genotype. I am most familiar with the genetics of autism, and there is no gene that is responsible for more than a few percent of autism incidence (from multi-thousand GWAS). Autism is a disorder with extremely high heritability, but they can’t find the genes.

Autism (like all neuropsychiatric disorders) has to be a problem of development. Either neurodevelopment lead to a dysfunctional neuroanatomy that instantiated bad functionality, or neurodevelopment didn’t lead away from a dysfunctional neuroanatomy instantiating bad functionality. No doubt genes are important, but genes are not and cannot be the whole story.

Actually that may not be true for a couple of reasons. The most important is that I think it is incorrect to assume that Africa = “black faces.” Africans have the most skin color diversity in today’s world, and I think it is a mistake to homogenize the people in that region. If the range of skin color is greatest in Africa today, I’m not sure exactly what that says about the skin color of humans 100,000 years ago, but it would make more sense in this context that such a “face template” would be sufficiently flexible to account for a range of skin colors. If there are differences depending on skin color, I’m not sure that we can assume your “black faces with light eyes” is a better option

It’s an interesting proposition that given that there is some sort of template, it ought to respond more readily to black faces over white faces, irrespective of the child’s “race”. Of course, this would mean that the template we’re referring to is sufficiently specific for this, which might not be the case at all. For example, Pascalis and Kelly as I mentioned above, cited some really cool studies done with monkeys where they lost their conspecific face recognition ability (analogously to how Japanese children lose their ability to differentiate between the English phonemes L and R in the language domain). I don’t know about this one, I haven’t seen any work on it, but it would certainly be interesting to test.

I don’t mean to invoke authority here, but this is really sort of dragging on. The consensus among face researchers, seems to be that there is innate specialisation for face recognition (see e.g. Pascalis and Kelly, 2009; Kanwisher, 2000; Chien, 2011; Johnson, 2005), but there is less agreement as to the extent of this specialisation. Indeed, the only ones that I’m aware of that have actually questioned this are the Italian researchers previously mentioned, who’ve argued that these are domain general factors – that is, it’s not the geometric properties of faces per se that trigger the attention bias, but other more general geometric properties (such as the previously mentioned top heaviness and congruency) that are properties of the visual system as a whole (or something along those lines). This position is generally not “mainstream”, as it were, and Chien (2011) found that these biases disappear by the age of ~3 months, which agrees with Johnson and Morton’s CONSPEC/CONLERN model (and in fact a proposition by Pascalis and Kelly that the low spatial frequency detector CONSPEC is suppressed like a lot of other developmental reflexes, e.g. the grasping reflex). I don’t have the expertise in this field to advocate one view over the other, I can just reflect the consensus.

“Infants up to 9 minutes old have been found to have an attentional bias towards faces, so either there is a genetic basis for this preference, or it occurs within in the first 9 minutes of life.”

These are not the only two options consistent with the data of facial attention at 9 minutes. A preference for looking at objects with a spacial frequency similar to that of faces is sufficient, and that need not be genetic, it could be developmental.

A difficulty with the data generated to support the CONSPEC and CONLERN ideas is that it uses dark eyes/mouth on a white background. We know that humans evolved in Africa. Presumably that is where any “face template” also evolved. We should expect any genetically encoded “face template” to better match the faces experienced over long evolutionary time, which would be black faces with light eyes.

When researchers are using stylized images to test infant visual cuing, they don’t know what aspects of the images the infants are actually cuing on. It might be a simple spacial frequency, or something else. Adults have such highly tuned face recognition pattern recognition that pareidolia is extremely common.

http://www.pnas.org/content/102/47/17245.full

In primates, many if not most spontaneous birth occurs at night where visual cues to attend to faces would be absent.

Infants have much less contrast sensitivity than do adults. Images that are compelling to adults may not be visible to infants and they may be cuing on something other than a face-like pattern.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2765046/?tool=pubmed

Spontaneous waves of activation would be sufficient to allow Hebbian remodeling to achieve sensitivity to spacial frequency because spontaneous waves do contain relative spacial information. Spontaneous waves don’t contain face-like template information.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2946625/

I simply don’t agree that there is overwhelming evidence that a visual human face template develops in utero. I don’t think there is sufficient evidence to reject the null hypothesis that the visual system develops the ability to discriminate objects by their geometry after being exposed to objects with different geometry so as to produce the neuronal remodeling to instantiate pattern recognition.

I now realize how wrong I was……..

I am unfamiliar with any potential mechanisms for which this could develop in utero, but there is pretty overwhelming evidence that it does, and that it is very general to begin with (e.g. preference for congruent objects that are top heavy), but soon develops into a higher resolution face recognition mechanism, together with, as you rightly point out, the improving visual acuity of the visual system. Of course, any talk of a template is a bit misleading because all this would mean is that you have a particular system that responds to the general geometric relationships that tend to be present in faces, such as the properties identified by the Italian researchers mentioned above.

http://www.ncbi.nlm.nih.gov/pubmed/21478887

Do you have a citation for recognition of faces?

The only ones I could find relating to faces there was a long delay between the restoration of sight and the testing of face recognition.

The report on S.B. by Gregory states:

“S.B.’s first visual experience, when the bandages were removed, was of the surgeon’s face. He described the experience as follows:— He heard a voice coming from in front of him and to one side: he turned to the source of the sound, and saw a “blur”. He realised that this must be a face. Upon careful questioning, he seemed to think that he would not have known that this was a face if he had not previously heard the voice and known that voices came from faces.”

http://www.richardgregory.org/papers/recovery_blind/contents.htm

This seems to indicate that S.B. was not able to recognize faces by sight a priori, but needed to know that he was looking at a face to be able to appreciate that it was a face. That such an association can be made in seconds shows how difficult it would be to demonstrate a “template” before there was exposure to such a visual stimuli.

I agree that it is possible to have visual detection neuroanatomy pre-coded by DNA. I just don’t think there is any compelling evidence for it, or to reject the more parsimonious idea that facial recognition develops just like every other type of visual pattern recognition develops. If the visual processing system has plasticity such that detection of some objects needs to develop, how is that consistent with facial recognition not needing to develop.

Faces can still be “special” in a no-template development via plasticity model. Other sensory modalities, sound (mother’s voice), smell (mother’s odor), touch (mother’s kiss, taste (mother’s milk) can all be additional cues that key the infant to attend to the visual object that is the source of all of these good things.

There is sound exposure in utero, so sound pattern recognition at birth doesn’t need to be pre-coded by DNA. Olfactory neurons are directly connected to specific parts of the brain, so no development is needed for olfactory detection.

I think that insects probably do have pre-coded visual pattern recognition neuroanatomy. But the insect retina and associated immediate signaling is completely specified and is fixed so there is a one-to-one mapping between visual signals and the decoding of the images those visual signals represent.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2871012/?tool=pubmed

Vertebrate visual system is not pre-coded and fixed, so there has to be plasticity to get the light detection cells and the visual data processing cells connected together with the right mapping. Without the connection with the right mapping, there can’t be high fidelity pattern recognition.

It is perfectly acceptable to figure out what evolution can and can’t do. Evolution is not magic. Evolution is not teleological. Evolution can only generate organisms via physically realizable processes and those organisms must obey the laws of physics. We should be extremely skeptical of features that violate some of these principles.

I don’t dispute that people have postulated a “time window” beyond which visual plasticity is zero. Showing that this is not the case does not demonstrate that there is a face template that is coded for by DNA.

When people state that a feature is directly coded by DNA, there needs to be some evidence that this is the case and that development via plasticity models are excluded by data. Plasticity can explain every feature of the brain that I am aware of. I appreciate that my view that plasticity explains essentially everything is a minority view, but I think it is human hyperactive agency detection that compels people to look for a “top-down” control system that is directing the development of observed features.

Wanting there to be a “top-down” control system is a major example of flawed thinking behind much of science. There is no “top” in physiology. All global aspects of physiology are only emergent properties of bottom-up systems.

And I’ll just throw this out there again to you et al. doing the same: don’t say what the brain (or nature generally) can and cannot be or do when no one understands the mechanisms involved, and this is doubly so with the products of evolution. This sort of reasoning will almost always lead you astray. I would think in terms of liklihoods, keep an open mind, and look at existing work in testing your ideas.

We absolutely CAN have a face detector, phoneme detectors etc., even if this seems unlikely (and I agree that it’s less parsomonious adn should be treated with skepticism). There is an incredible amount of stability in the cortex’s visual ventral stream for body areas, landscapes, faces, ecological size, just as there are clear modules in visual cortex for edges, through shapes color and motion. We have litte idea how they come about.

Is there a template for a two-headed person in the genome (see above)? Is there a template for every congenital difference? If the phenotype develops because there is a “template” of that phenotype in the genome, then the genome has to have a “template” of every phenotype trait that can be expressed. There isn’t enough information content in the genome to code for a template of every potential phenotype trait.

You can’t have a high fidelity face recognition template at birth because visual processing is not high fidelity at birth. The development of high fidelity vision requires high resolution visual input and there isn’t high resolution visual input in utero.

Current data is insufficient to differentiate between a hypothesis where the genome codes for an innate face template, or codes for neuroanatomy that is sufficiently general and can instantiate multiple face templates and which is primed at birth to prune and self-modify to become a finely tuned face recognition that keys on the specific faces the infant is first exposed to. The general pattern recognition neuroanatomy that prunes to match what it is exposed to is enormously easier to evolve, much easier to encode in the genome and doesn’t depend on facial features specific to modern humans. It is simpler to evolve and could evolve over a much longer period of time. Why would we adopt a hypothesis that is more complicated (an innate human face template) when a simpler hypothesis fits the data?

What evolutionary value does an innate face template have over a compulsion to attend to sources of sound and visually key on those sources of sound? There is exposure to sound in utero, so pattern recognition of maternal voice could develop in utero and be a very strong cue for infants to key on.

We don’t actually know if there is more or less plasticity in the facial domain than in the language domain because those occur over very different time scales and infants can’t report or be tested with sufficient precision. Language is an interactive process where people need to develop the neuroanatomy to both decode meaning and generate language that encodes meaning. Face recognition is pretty much one-way and passive.

Maternal bonding occurs very quickly (hours) and persists for a lifetime. It only takes a single exposure to something to form a memory of that exposure. A memory happens to be instantiated in neuroanatomy such that the memory is accessible to consciousness. Why couldn’t there be unconscious memories also instantiated by neuroanatomy which are just as fast and just as persistent?

I agree that there is a lot of thought that there are “templates” of various sorts encoded in the genome and expressed in neuroanatomy in utero. I think that much of this thinking is mistaken and derives from the human compulsion to see “top-down” control due to hyperactive agency detection. Humans are primed to detect agency, even when it is not there. This is the same hyperactive agency detection that wants to see a “mind” in “control” of the brain, causing the brain to do what it does from the “top-down” control by the mind.

There are known mechanisms by which high fidelity pattern recognition can be instantiated following exposure to high resolution signals (Hebbian remodeling). What is the mechanism by which any type of pattern recognition can be instantiated by the genome? Pattern recognition is necessarily an emergent property of many neurons, millions at least. How do those millions of cells “know” how to connect and arrange themselves to recognize a pattern coming in on nerve signals over nerves that have not yet processed sensory input? There isn’t any non-teleologic mechanism.