Versatile award

The blogger Mados has nominated me for the Versatile Blogger Award and written some nice things about me and 14 others. There is no actual award. There is: the nomination, the write-up and the opportunity to nominate others.

Here is the link to the Mados blog, http://mados.wordpress.com/2012/08/27/versatile-blogger-award, where you can read about the author and the other nominees – a very interesting read.

 

This is what I am supposed to do:

  1. Thank the person who nominated me – I have but I will again, thank you Mados.

  2. Nominate 15 bloggers, whose blogs I enjoy to read, and notify them. They are below, alphabetically.

  3. Post the Award image. Here it is. versatile award logo

  4. Tell seven things about myself. One, I am female; two, in my 70s; three, English speaking; four, raised Canadian, citizen of UK, living in France; five, educated in bio-science & computers but interested in many things; six, left-handed and dyslexic; seven, blogging.

In my blog I try very hard to keep to one subject, consciousness, and not stray too far from that topic. But for this list I am going to stray and include a few blogs that have nothing to do with neuroscience. I am going to use alphabetical order to avoid appearing to rank the nominees. (I have a built in dislike of pyramids or chain letters etc. I am treating this as just a form of communication, a sort of carnival type of thing, and I insist that my nominees should not feel that I am trying to force them to carry on the chain. They can or not as they please.)

 

Babel’s Dawn http://www.babelsdawn.com

One of the first blogs that I followed and one that convinced me to start my own blog was Babel’s Dawn written by EB Bolles. Nowadays it is less active than it used to be with just occasional posts, because it has resulted in a book by the same name. If you are interested in the origins of language, there are a load of posts to interest you just waiting in the archives of this blog; everything you want to know – the evidence, the theories, the disputes with good manners and good sense.

 

Berry Deep France http://www.fabfrog.com/

Dirk Beauregard is a “late mid-fortysomething journalist cum teacher cum musician trying to carve out an existence in deepest rural France – namely Bourges in the Cher”. This is my nearest town and it is very interesting to have reports on what is happening locally in English. He is a man with an interesting mix of topics and points of view.

 

BishopBlog http://deevybee.blogspot.fr

Deevy Bishop is an Oxford scientist who blogs on many aspects of science in general and neuroscience in particular. I enjoy her style and appreciate her critical approach.

 

Brain Pickings http://www.brainpickings.org/

Maria Popova’s postings are like pages in a scrap book: interesting quotes, lists and facts. “Brain Pickings is a human-powered discovery engine for interestingness, culling and curating cross-disciplinary curiosity-quenchers, and separating the signal from the noise to bring you things you didn’t know you were interested in until you are.”

 

Conscious Entities http://www.consciousentities.com/

The blogger here is identified as Peter. He blogs on the philosophy of consciousness, explaining the theories of many philosophers and his own ideas. This is philosophy but written well enough that it does not put me to sleep. He keeps pretty tightly to consciousness which also is attractive to me and I have learned about a few good viewpoints from this blog.

 

Deric Bownd’s Mindblog http://mindblog.dericbownds.net/

Like Babel’s Dawn, this is another blog that I took to early and tried to use as a pattern. I thought if I can be as useful as Bownd, I will be worth reading. What you get here is an almost daily piece of neuroscience news, presented short-and-sweet, usually with an abstract or similar quote, and no misleading hype. As a bonus he also gives us piano playing from time to time.

 

Language Log http://languagelog.ldc.upenn.edu/nll/

This is a joint effort of more than 20 linguists (Mark Liberman and Geoffrey Pullum among them) somewhat centered around the University of Pennsylvania but with some contributors in other part of the US and in the UK. They comment (always from the linguistic angle) on questions people send them, current events, and recent publications. It is good scholarship but at the same time entertaining. There is something new every day.

 

Mind Hacks http://mindhacks.com/

Tom Stafford and Vaughan Bell contribute to this blog about the news in psychology. (There is a book by Tom Stafford and Matt Webb by the same name). The items they report and comment on come from a wide range of sources and often cover unusual topics. Although their topics are sometimes odd – they are always sensible and trustworthy.

 

The Neurocritic http://neurocritic.blogspot.fr/

Neurocritic writes clearly on the weaknesses in current neuroscience. “Deconstructing the most sensationalistic recent findings in Human Brain Imaging, Cognitive Neuroscience, and Psychopharmacology”.

 

Neurophilosophy http://www.guardian.co.uk/science/neurophilosophy

Mo Costandi blogs for the Guardian newspaper in the UK. He gives very well researched and written articles for the general but interested public, with no sensationalist ‘journalist’ hype or shortcuts.

 

Neuroskeptic http://neuroskeptic.blogspot.fr/

Neuroskeptic does not give a name but says he/she is a neuroscientist in the UK who “takes a skeptical look at his own field, and beyond”. Neuroscience and psychology are prone to faults of various kinds and this blog’s evaluations of research papers are very useful. He is always clear, knowledgeable, and to the point.

 

Oscillatory Thoughts http://blog.ketyov.com/

Bradley Voytek is a neuroscientist who blogs on his science and other quirky things (like zombies).

 

 

Reseach Digest http://bps-research-digest.blogspot.fr/

Christian Jarrett writes these posts for The British Psychology Society Digest. Each post is a straight forward review of a recent paper. It won an award in 2010 for ResearchBlogging (serious blogging on peer reviewed published research). This blog also has a weekly list of papers that have come out that week but were not covered in Jarrett’s postings – very handy. His reviews are very readable.

Sing your own lullaby http://singyourownlullaby.blogspot.fr/

Mariana Soffer’s interests range over much of art, science and technology. Her blogs are thoughtful – no two the same. She spans an English and a Spanish world and is always networking.

 

1513 fusion http://1513fusion.wordpress.com/

This is a quiet blog of poems, photos, artwork, stories and observations by the blogger, Harry Nicholson. He lives in northeast England and is very attached to his surroundings. I suggest you stop in a couple of times and see if this gem of a blog fits your taste. He also has a novel, Tom Fleck, and its publication started his blogging.

 

I should mention where I get the most information for my own blog, although this is not a blog and therefore does not get a award nomination: http://www.sciencedaily.com/news/ . When I find something here that I want to write about, I can follow in up.

 

Still much unknown about brain

How deep is our ignorance of the brain? We have just had another surprising discovery that shows how little we know. There is a whole physiological system in the brain, the size of the brain’s vascular system (all the arteries and veins in the brain) and the importance of the lymphatic system for the rest of the body. The system circulates cerebral spinal fluid at a speed and clears waste from the brain. (Citation below)

 

Of course there is a reason why it went unnoticed – it does not exist unless the brain is whole and working. That is not the only reason: it was difficult to see until recent advances in instrumentation; and, no one looked for it. But we have to notice that in general most of brain physiology does not exist unless the brain is whole and working and instrumentation is mostly new and problematic in neuroscience. It is a system made of astrocytes forming conduits outside blood vessels but following their path. Astrocytes have only recently been thought important to understand. These cells seem to wrap everything in the brain, not just protecting but also controlling and communicating. They are still understudied. This newly discovered system has been named glymphatic, a mixture of glia and lymphatic.

 

Regularly we have surprises like this. And we should by now recognized that it will be a few years before we have a somewhat complete model of the brain operations. This may be especially true of surprises having to do with consciousness.

 

There is a habit of rejection when it comes to surprises about consciousness. Libet was 30 years ago and there is still an industry in trying to disprove the results. This has resulted in more information and some changes in interpretation but still the gist of Libet’s experiments still stand. We register our decisions to act consciously, we take ownership of them, but we do not make them consciously, the decisions are formed before they are made conscious.

Note: again citation link is faulty. Try

http://stm.sciencemag.org/content/4/147/147ra111

  Iliff JJ, Wang M, Liao Y, Plogg BA, Peng W, Gundersen GA, Benveniste H, Vates GE, Deane R, Goldman SA, Nagelhus EA, & Nedergaard M (2012). A Paravascular Pathway Facilitates CSF Flow Through the Brain Parenchyma and the Clearance of Interstitial Solutes Sci Transl Med : 10.1126/scitranslmed.3003748
ResearchBlogging.org

Neural substrate of self-awareness

Researchers (Philippi and others) have investigated a patient with extensive damage in a location that has been suggested as the source of self-awareness to evaluate that hypothesis. (see citation below). The patient, known as R, has bilateral damage to the insula, anterior cingulate and medial prefrontal cortices. Some believe these areas are essential for basic self-awareness. But there are other views too.

 

In order to help settle this question, the team did a very thorough imaging of the damage and gave the patient a battery of tests to establish the extent of his self-awareness. R had amnesia which eliminated much of his autobiographical self-awareness. He also was not aware of his own loss of a sense of smell. These limitations were due to damage outside the area being studied. But aside from these two limitations, his self-awareness was intact.

 

Here is in the paper a very clear description of the types of self-awareness they tested for and the tests used. Those of you that have an interest in the components of self-awareness would find this interesting, and can read the original. The gust is that they recognized three types of self-awareness: core (feelings of the body, elementary self-consciousness, personal agency, ownership of actions and sensory perceptions, self-recognition, sentience); extended (autobiography, self-concept using physical, affective and personality traits); introspective (introspection, reflection on own mental states, actions/consequences, social skills).

 

The results severely weaken the idea that the insula, anterior cingulate and medial prefrontal cortices are essential for self-awareness. The paper cites other evidence in keeping with their results. What are the alternatives as the authors see it?

By contrast, the hypothesis implicating brainstem nuclei in generating the ‘‘primordial feelings’’ essential to Core SA is entirely compatible with our findings (as R does not have brainstem damage), and is in keeping with the fact that selective damage to brainstem tegmentum has long been associated with impaired consciousness. Furthermore, this hypothesis is also consistent with the striking presence of core SA and basic emotional functioning found in children who are missing their cortex due to hydranencephaly.

Intact regions of R’s cerebral cortex, such as the posteromedial cortex (which includes the posterior cingulate, the precuneus, and the retrosplenial cortices) and the inferior parietal lobule, could constitute the critical substrate for preserved SA in R. Both of these areas are critical nodes of the Default Mode Network. Activity in the posteromedial cortex, in particular, has been consistently associated with consciousness. Of note, R had preserved functional connectivity within this region of the brain. Intracranial recordings have also associated the posteromedial cortex with self-referential processing. Moreover, Dastjerdi and colleagues found that intracranial electrodes placed near the retrosplenial cortices responded preferentially to autobiographical memory stimuli. These findings are consistent with neuropsychological research which has implicated the retrosplenial cortex in autobiographical memory retrieval. R’s intact retrieval of some autobiographical knowledge might be mediated in part by the retrosplenial cortices. More generally, our findings are compatible with hypotheses invoking distributed neural systems as a substrate for SA and its components.

 

To me this suggests a system of great antiquity that is based in the brain stem, passes through the mid-brain to the cortex, and is dispersed in the cortex. The same picture as can be seen in consciousness in general – driven by the brain stem, up to reticular formation, passing through the thalamus and involving much of the cortex. Why should awareness of self be much different from awareness of the rest of the world?

Note:

Sorry, I don’t know how this happened. The citation is copied from ReasearchBlogging is usually for posting there but does not work. Here is another link

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0038413

 

 

ResearchBlogging.org

Philippi CL, Feinstein JS, Khalsa SS, Damasio A, Tranel D, & et al (2012). Preserved Self-Awareness following Extensive Bilateral Brain Damage to the Insula, Anterior Cingulate, and Medial Prefrontal Cortices PLoS ONE, 7 (8) : 10.1371/journal.pone.0038413

It is official – revisited

I have decided to do another post on the subject in view of the comments to my last post. I have over 10 times my usual visits and many more comments than usual. This is a surprise to me because I didn’t think this was a powerful or provocative posting. One comment questioned the number of participants who signed the declaration, and he was there and should know. I stand corrected – all participants did not sign.

My impression when writing the original post was that most readers of my blog would find the idea of animal consciousness a bit ‘old hat’. And that seems the case; most comments do not question animal consciousness. But my statement that humans are not uniquely unique did not seem as passe.

Of course I would agree with what was, mistakenly, attributed to Stalin – sufficient quantity has a quality all its own. Really big differences are uniquely unique. We are not alone in the world in having culture because primates and elephants at least have some culture that they hand down the generations. Human culture is on a different scale, so different that it can be thought of as uniquely unique.

But our culture says little about our biology or our consciousness. Culture feeds itself so it needs no biological change to grow, it just needs a biological starting point. Look at a exponential curve. It rises slowly for a very long time before its increasing rate (which has always been there) becomes apparent. Soon it seems to turn a corner (again our imagining a corner) and heads very quickly up towards the heavens. As we share the rudiments of cultural transmission with the great apes, we have probably been on a cultural growth paths for millions of years. Very few biological changes are necessary, a few of course or we would have a level of culture similar to apes, but not many. And certainly I can not think of any changes in the mechanisms of consciousness that would need to be modified.

In the early ’60s, long before they were closed to the public, I saw the paintings in one of the Cro Magnon cave sites in France. It was an epiphany. These paintings were done by people who thought like me, or even better. No one can convince me that we have a better mechanism for consciousness now then we did 30,000 years ago. And I do not believe that each generation of painters learned how to make these beautiful images from scratch. There had to be an apprenticeship; they had a culture.

Forget about jumps and great leaps forward, genes for language, genes of maths. Homo sp. has very little more than we started with. It is culture that gives us language, control of fire, tools, the dog partnership, agriculture, cities, industrialization, finding the Higgs. Each generation standing on the shoulders of the last. Similar brain, similar intelligence, similar biology, but each generation has a larger more sophisticated culture.

Consciousness to about how the brain does a global awareness of itself and its on-going activity in its environment. There is going to be a difference in the content of my consciousness and that of my dog. But there need be no difference in the nature of how the consciousness is produced. Our consciousness as a biological function is not uniquely unique – it is not even figure in the list of what makes us unique as a species. It is the culture that is so different to animals.

If we are going to understand how consciousness is produced, we have to do comparative biology. Culture is easy. We know how it works: communication, example, training and the like. We don’t know how consciousness works. There are many theories, little evidence and no consensus. So it is helpful to get the ‘our consciousness is not found in animals’ business out of the way so that we can better study what is common.

Here are links to some old postings about this subject:

http://charbonniers.org2011/11/13/uniqueness/

http://charbonniers.org2010/09/06/worms-and-us/

http://charbonniers.org2010/07/20/the-brains-of-birds/

http://charbonniers.org2008/12/27/not-just-a-few-animals/

http://charbonniers.org2008/11/24/occams-razor-and-rules-of-thumb/

http://charbonniers.org2008/08/04/are-animals-conscious/

 

It is official

What has been known/suspected for many years is now accepted science – consciousness is not unique to humans. On July 7 the Cambridge Declaration on Consciousness was signed by a group of recognized authorities (cognitive neuroscientists, neuropharmacologiests, neurophysiologists, neuroanatomist and computational neuroscientists). They were the attentees at the Francis Crick Memorial Conference on Consciousness in Human and non-Human Animals. The document was presented by Philip Low, David Edelmann and Christof Koch and was signed by all participants at the conference. They declared:

“The absence of a neocortex does not appear to preclude an organism from experiencing affective states. Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviors. Consequently, the weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Non-human animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.”

 

We have tool using, problem solving, and planning out of the way and now consciousness, so perhaps we can stop thinking that humans are so very, very difference from the rest of the animals. It is far more useful to be finding the evolutionary continuums between humans and other animals, rather than trying to find ways that we are unique. Of course we are unique in the sense that each-and-all species are unique. That is a trivial question of definition; species differ significantly from one another. But we are not uniquely unique. Everything we have must have a roots and commonalities in other primates. Accept it and use it to obtain a better understanding of ourselves.

Addition: thank you, Henk Poley, for your comment and link which I have brought up to the level of the post  -

 A direct link would have been nice: http://fcmconference.org/img/CambridgeDeclarationOnConsciousness.pdf

 

Wisdom and well-being

A word like ‘wisdom’ is not scientifically defined and has a very wide everyday meaning. I am sure that anyone taking a pole of what people thought ‘wisdom’ meant would get as many definitions as the number of people consulted. However, it is central to the word that wisdom is not something you are born with but it comes with experience and maturity, even old age. It is not the same as intelligence; it is not the same as knowing a lot of information. We think of wise people as being able to solve vague and complex problems, especially social ones. But we also think of wise people as avoiding problems to begin with so they don’t have to solve them. We think to wise people as stable – not overjoyed or terribly sad but quietly content with an appropriate reaction to events. They are people-friendly, ready to give help and advice.

A recent paper takes the viewpoint that wisdom is a method of thinking (A Route to Well-Being: Intelligence Versus Wise Reasoning, by Grossman, Na, Varnum, Kitayama, Nisbett). The researchers concentrated on these strategies: consider the perspectives of other people, recognize that change occurs, see that there are many ways for the future to unfold, know the limits of certainly, search for compromise, try to solve/avoid conflict. The strength of this sort of definition is that it fits with measurements of other things. People who think in this way have greater life satisfaction, less negativity, good social relations, avoid ruminating and live longer. The ability to think this way increases with age and experience.

On the other hand, intelligence does not fit with satisfaction, longevity and the other benefits of wisdom.

Here is the abstract:

Laypeople and many social scientists assume that superior reasoning abilities lead to greater well-being. However, previous research has been inconclusive. This may be because prior investigators used operationalizations of reasoning that favored analytic as opposed to wise thinking. We assessed wisdom in terms of the degree to which people use various pragmatic schemas to deal with social conflicts. With a random sample of Americans, we found that wise reasoning is associated with greater life satisfaction, less negative affect, better social relationships, less depressive rumination, more positive versus negative words used in speech, and greater longevity. The relationship between wise reasoning and well-being held even when controlling for socioeconomic factors, verbal abilities, and several personality traits. As in prior work, there was no association between intelligence and well-being. Further, wise reasoning mediated age-related differences in well-being, particularly among middle-aged and older adults. Implications for research on reasoning, well-being, and aging are discussed.

and their conclusion:

Our results suggest that lay beliefs about the relationship between reasoning abilities and well-being are correct, with one caveat. Whereas wise reasoning about social conflicts contributes to well-being, abstract cognitive abilites (as measured by intelligence tests) do not. On the practical side, the present work suggests that despite the cognitive declines often associated with older age, the increasing number of older adults may be of great value for the social and emotional well-being of our future communities.

Correlates of memory

A review article by Suthana and Fried (citation below) has just been published on the nature of medial temporal lobe neurons. It is very informative.

 

The medial temporal lobe (MTL) includes the hippocampus, entorrhinal cortex, perirhinal cortex, parahippochampal cortex, and amygdala. It is associated with memory but not perception.

The ability to form new episodic memories, which can later be consciously accessed, relies on an intact hippocampus and surrounding MTL. However, other functions, such as visual perception, do not depend on an intact MTL . …The MTL receives multimodality sensory input from wide areas of the cortex, thereby offering the possibility of convergence and integration of information. Within the MTL, the hippocampus is positioned at the top of a multisensory hierarchy, receiving converging incoming sensory information through the entorhinal cortex that is either object identifying (via perirhinal cortex) or spatially informative (via parahippocampal cortex). For the MTL to encode a given episode in time properly, the event must be first perceived and processed in upstream sensory cortices.

 

The response of MTL neurons has been recorded and characterized.

(i) Responses are selective. MTL neurons can respond to particular stimulus categories (e.g. faces, outdoor scenes, animals, etc.) or to individual stimuli (e.g. a family member, a famous individual, or a particular landmark) during the passive viewing of visual stimuli.

(ii) Responses are invariant. An MTL neuron may respond to a particular stimulus, such as a particular face or landmark, but in addition it will also respond to other stimuli representing that particular face or landmark, even if these stimuli are distinctly different in stimulus features compared with the original stimulus. Thus, a neuron may respond to a picture of the Sydney Opera House and exhibit no response to 50 other landmarks, yet also respond to many permutations and physically different representations of the Sydney Opera House, seen in color, in black and white, or from different angles. In fact, the neuron may also respond to the iconic representation, namely the words ‘Sydney Opera’, which is obviously different in its visual properties compared with the image of this landmark. Recently, it was shown that this invariance crosses modalities, meaning that MTL neurons may exhibit a selective and ‘invariant’ response to a particular stimulus out of 100 images and do so independently of the sensory modality (visual image, audio, or written iconic representations) through which the stimulus was presented. Results were consistent with the anatomical hierarchy within the MTL; the highest percentage of neurons with modality-independent invariant responses was found in the hippocampus and entorhinal cortex, compared with the amygdala or parahippocampal cortex.

(iii) Responses are late. The selective and invariant responses described above are of relative long latencies, often in the 300–500 ms range. Interestingly and consistent with the anatomical hierarchy, responses in the parahippocampal cortex are significantly shorter than those in the hippocampus, amygdala, and entorhinal cortex, but still with longer latencies than those observed in animal studies.

(iv) Responses are associated with conscious perception. Using flash suppression and backward masking paradigms, it has been shown that selective MTL responses are mainly triggered when accompanied by the participants’ conscious perception or recognition of the stimulus. When varying the display time of an image between 33 and 256 m, MTL neurons selective for an image significantly increase in firing rate only if the image is recognized by the subject, even if the image is presented for as briefly as 33 ms. Conversely, if the subject reported no recognition of the image, the MTL neuron selective for that image is mostly silent.

  1. Responses can be internally generated. The act of re-experiencing a previous episode can be internally generated or cued by an external percept within the environment. Generating an internal percept of a stimulus through imagery in the absence of an external visual stimulus, recruits the same MTL neuron activated during viewing of the stimulus itself. Subjects’ ability to modulate these neurons was studied … Subjects were told to try and control which of two competing images would be projected on an external display; the displayed images were controlled by the firing rate of recorded MTL neurons selective for the two images. Subjects were able to control successfully which image was projected by altering the firing rate of two independently selective neurons independent of the visual input of the stimulus on the screen. These results highlight the power of internal representation to override sensory input. They also illustrate how human single neuron recordings can illuminate mechanisms of conscious perception, regardless of whether they are externally or internally generated.

 

This does appear to be the sort of response that could give us episodic memory.

Why are these responses present in the MTL, and in the hippocampus and entorhinal cortex in particular? Given the critical role of these regions in episodic memory, we posit that these responses are central in the transformation of novel stimuli to representations that can be later consciously retrieved as episodic memories. As such, these representations need to have detail but also abstraction (i.e. the loss of detail), so that they can be later summoned by internal as well as external cues. It is also possible that consciously perceived familiar stimuli trigger the recollection of an associated memory and, thus, reactivate MTL neurons. … Although patients with damage to the MTL can no longer form new episodic memories, their visual perceptual function remains intact. The correlation of single neuron responses in the MTL with specific conscious percepts does not imply that these regions are necessary for conscious percepts, yet these responses may reflect the link between conscious percepts and episodic memories that can be later

consciously accessed. … Strikingly, hippocampal and entorhinal neurons that were selectively active during the initial viewing of distinct episodes were similarly reactivated just before the verbal report of recall of those very same episodes. Although sustained selective responses during viewing of episodes was present in neurons of other brain regions, such as amygdala and frontal cortex, the specific reactivation before reported recall was only present in the hippocampus and entorhinal cortex.

 

Interestingly the synchrony of waves may imply a that memory and consciousness are working together.

Human intracranial studies have shown that the spiking rate of single hippocampal neurons predicts whether a recently learned item will be remembered. In addition, intracranial recording of local field potentials (LFPs) have yielded important insights. Theta LFP oscillations (3–8 Hz) have been widely implicated in human memory and the strength of their amplitude measured in the MTL has been shown to predict the success of episodic encoding in humans. Interestingly, the theta amplitude that predicted recall success was also strongly linked to the gamma oscillation (30– 100 Hz). The phase of theta oscillations and their relationship to gamma oscillations in monkeys and humans have been related to memory performance. … It has been hypothesized that the theta- spiking relation may reflect the cued recall of an upcoming item stored in memory. A recent study in humans showed that the relation between spiking and theta during encoding predicted memory success. … A tighter coordination between hippocampal single neuron spiking and the simultaneously recorded theta LFP oscillation during initial viewing of the image predicted the success of the formed memory for that image . These results implicate a direct role for theta-linked spiking activity in episodic memory.

 

ResearchBlogging.org

Nanthia Suthana, & Itzhak Fried (2012). Percepts to recollections: insights from single neuron recordings in the human brain Trends in Cognitive Sciences, 16 (8) DOI: 10.1016/j.tics.2012.06.006

How truthiness works

Truthiness is a word coined by Stephen Colbert in 2005 but already a recognized concept. Wikipedia defines it as “a quality characterizing a “truth” that a person claims to know intuitively ‘from the gut’ or because it ‘feels right’ without regard to evidence, logic, intellectual examination, or facts.” In other words, truthiness just feels right and therefore resembles truth.

There is an item in ScienceDaily (here) reporting on a paper by Newman etal, Nonprobative photographs (or words) inflate truthiness in Psychonomic Bulletin & Review 2012. They used statements with and without photos to see whether photos affected the agreement with the statements. The photos illustrated the topic of the statements but added no verification of them.

In a series of four experiments in both New Zealand and Canada, Newman and colleagues showed people a series of claims such as, “The liquid metal inside a thermometer is magnesium” and asked them to agree or disagree that each claim was true. In some cases, the claim appeared with a decorative photograph that didn’t reveal if the claim was actually true — such as a thermometer. Other claims appeared alone. When a decorative photograph appeared with the claim, people were more likely to agree that the claim was true, regardless of whether it was actually true.

Why should this be? The photos appear to add truthiness to the statements.

Across all the experiments, the findings fit with the idea that photos might help people conjure up images and ideas about the claim more easily than if the claim appeared by itself. “We know that when it’s easy for people to bring information to mind, it ‘feels’ right,” said Newman.

A confusion between easy and right – dangerous.

Fringe feelings

There are those fringe feelings in consciousness that are not perceptions or actions but just feelings: parts of various emotions and hints about what is happening. A feeling of familiarity, of distrust, of ‘tip of the tongue’ are fringe feelings so are feelings of anger or happiness. Here is a new pair introduced by Wray Herbert (here). They are similar, he calls them ‘Whew!’ and ‘Finished!’.

Wipe your brow, slightly roll your eyes, relax your shoulders and let out a forceful little puff of air and feel the relief. You have either survived a very close call or you have finished a huge task. This might be the same fringe feeling, relief, but Herbert explains how they are different.

Are there really Whew! moments and Finally! moments—very different circumstances that generate the same basic emotion? Sweeny and Vohs decided to explore this possibility in a couple experiments. They wanted to see if, on closer examination, the two kinds of relief might differ significantly in nature and consequences. … The scientists suspected that the two kinds of relief would produce different results, cognitively and emotionally. And that’s just what they found. Those who were recalling a Whew! experience were much more likely to fixate on the most dire outcome they might have experienced. Those recalling a Finally! experience also engaged in what-if thinking, but they tended to focus on how things might have turned out better. Sweeny and Vohs believe this is because “what if” thinking arises to guide future behavior: When we narrowly dodge a bullet, it’s adaptive to think about how we might do that again (or even better) next time around. Such strategizing is not so beneficial when one has completed a task that’s either unavoidable or, in the end, gratifying—even if it is a relief to do so. …That is, those who were thinking Whew! were more apt to imagine the worst, and this catastrophic thinking led to feelings of being alone and disconnected. Their minds may have been strategizing for the future, but in the meantime they were suffering through painful what-if scenarios. … The other form of relief—Finally!—may also have some adaptive value for the future, though quite different. By engendering positive thinking and solidifying a sense of belonging, it might help reinforce the motivation to push on when faced with life’s challenges.

This fits with what we have been thinking about fringe feelings in consciousness. Just like it is advantageous to remember our perceptions and actions, it is also advantageous to remember the ‘colour’ of events: their emotional settings (made me angry), the train of mental work that they set in motion (must recall who that is), and the lessons that should be learned (never go that close to the edge again). The immediate memories with marks of significance like this are unlikely to disappear quickly by being carelessly lost in consolidation.

Towards understanding brain architecture

When I was much, much younger, I thought it would not be possible to map the brain – so many cells, so many connections, and so little structure. I was very wrong. There is structure. Every year there seems to be more of the structure identified.

 

There is a paper out by Wedeen etal (see citation below) that traces the nerve fibers of the brain using diffusion fMRI and shows they form a 3 dimensional grid. A common structure seems to be two ribbons on parallel fibers that cross each other at 90 degrees. Thus every fiber in the one ribbon will come extremely close to every fiber in the other ribbon. Think of a small piece of a simple weave cloth. One length-wise thread will lie against every width-wise thread as it goes from the top to the bottom of the cloth. Every pair of threads – one warp and one weft will meet – no pairing will be missed. A third set of fibers can pass through at right angles to the first two.

Many areas of the cortical white matter were studied and the organized orthographic crossings were always found. All pathways had a sheet structure. The structure resembles and is continuous with grids in other brain regions like the basal ganglia and the brain stem.

 

The structure was found in rhesus, owl monkey, marmoset, the pro-simian galago, and human subjects.

Strong homology of deep cerebral grid structure was found across all species studied. These included the grid systems of the callosum, sagittal stratum, and supra-Sylvian pathways, as well as the crossing of the fornix and anterior commissure in all species studied … In the rhesus monkey, central and sub- cortical grid structures, including those of the major frontal sulci (principal, arcuate, central), fit together continuously like a jigsaw puzzle. Thus, we hypothesize that the complex connectivity of the cerebral mantle represents a continuous elaboration of the simpler core.

 

From a embyonic developmental viewpoint of control by chemical gradients, it is not a complex structure.

This structure has a natural interpretation. By the Frobenius theorem, any three families of curves in 3D mutually cross in sheets if and only if they represent the gradients of three corresponding scalar functions. Accordingly, we hypothesize that the pathways of the brain follow a base-plan established by the three chemotactic gradients of early embryogenesis. Thus, the pathways of the mature brain presents an image of these three primordial gradients, plastically deformed by development. … Grid structure should restrict and simplify axonal path-finding compared with models that allow less constrained and less correlated connectivity within and between cerebral areas. If grid structure guides connectivity similar to the lane markers in a highway, then navigation would be reduced from a general 3D problem to a far simpler question of when to exit.

 

We can see how this sort of structure could start with more or less everything connected to everything and then during later fetal development and early childhood destroying the un-wanted connections. We can also see how this would be a useful system for plasticity (creating and modifying connections) without having to grow many new axons.

this structure supports incremental modification of connectivity by geometric modification within broad continuous families of parallel paths. Thus, the grid organization of cerebral pathways may represent a “default connectivity,” on which adaptation of structure and function can both occur incrementally in evolution and development, plasticity, and function.

 

A review by Zamora-López etal (see citation below) looks at the nature of networks in the brain, looking at how the brain can be both local and global at the same time.

A prominent problem is that a collection of specialized functions alone cannot give rise to a coherent perception of the reality. For that, different parts of the brain need to communicate and their information needs to be combined. Physiological recordings with multiple electrodes have revealed that distant neurons can synchronize, and neuro-imaging studies have extensively reported the co-activation of distant brain regions under different experimental conditions. These observations have set the foundations for novel approaches to understand the brain: that networks of segregated but interacting processes govern neural dynamics on top of the processing of the specialized regions. At the hidden ground of those functional and dynamic observations lies the fact that the neurons in a nervous system form a vast network with a mixture of both local and long-range connections.

 

The authors look at the nature of the brain’s networks, mainly by measurements of various network parameters in cats.

First, these networks are densely connected. Although far from an all-to-all connected system, approximately 30% of all possible links are present. As a consequence, cortical areas are all at very few processing steps of each other. … Second, the path of information transmission between two cortical areas is not unique, but there exists many alternative routes through which information can flow. These two observations support the notion that the cerebral cortex is a highly interactive information processing system, and is dynamically flexible. Although cortical regions might specialize in the processing of a particular function, they do not operate independently, but in strong influence of each other. The fact that information can flow through different alternative paths significantly enhances the richness and complexity of the processing capabilities of the system with a limited number of resources. If the system were provided with mechanisms to selectively activate or inactivate paths of communication, the range of dynamical states it can host increases significantly. In the brain, inhibitory connections may very well be responsible for such switching dynamics and permit that the resources used by each process self-organize by mutual and transitory competition.

 

Sensory processing begins in very local groups in parallel with one another.

However, in order to generate a coherent perception of the reality, the brain needs to combine (integrate) this multisensory information at some place and during some time. For this to happen, the paths of information need to converge. Whether integration occurs in specialized and localized regions of the brain, resembling information processing of sensory features by specialized regions, or it happens as a consequence of distributed but coordinated processing in multiple areas is still a subject of debate. During the last decades, multi-electrode recordings have demonstrated that distant regions of the brain undergo transient states of correlated activity as the consequence of behavioral responses to sensory stimuli and cognitive tasks in non-human primates. Current neuroimaging techniques permit to observe the whole brain at work, revealing the occurrence of patterns of correlated activity between distributed cortical areas. From an anatomical point of view, it has been argued that the functional capacity of the nervous system to balance between segregation (specialization) and integration is facilitated by its structural organization.

 

They describe the architecture of cortico-cortical networks:

(i) cortical areas are at very short processing paths of each other (small-world property), (ii) there are many processing paths between two cortical areas, (iii) they are organized into a few modules, and (iv) they contain few highly connected areas, hubs, which (v) form a rich-club at the top of the network hierarchy. … Although

regions exist which are specialized in a particular function, they do not operate independently. They work under the constant influence of each other. The modular and hierarchical architecture of the cortical networks represent the physical substrate that permits the brain to simultaneously process information of different modalities (parallel processing) and to integrate that information toward the generation of a coherent, global representation of the reality.

 

The small-world, rich-club, heirarchical network model answers many questions as well as mathematically fitting much of the data.

On the one hand, both physiological experiments and the study of patients with localized brain lesions have long evidenced that brain and cortical regions specialize in particular functions. On the other hand, during the last two decades, micro-electrode recordings at multiple sites and neuroimaging studies, have shown that distant regions of the brain undergo transient states of correlated activity. Based in these observations, a networked perspective has started to dominate in which brain activity is regarded as functional networks which rapidly emerge and dissolve, governed by coordination dynamics according to the sensory stimulation and the ongoing activity. Several models have been proposed that high-level functions are represented by distributed, interactive, and overlapping networks of neurons, which transcend any of the traditional subdivisions of the cortex by structural (cyto-architecture) or functional criteria.

Now, studying the anatomical connectivity of cortical and neural networks we find that, indeed, the nervous system is organized such that both approaches coexist. While different parts of the system specialize in performing particular functions, brain function is to be understood as emerging from the collective working of its constituents without a single coordinating center. The modular organization of the neural connectivity supports the specialization of different parts, and the highly interconnected hubs are responsible for the integration and/or coordination.

 

I have a reservation on both these papers. They do not deal with the connections with the thalamus, cerebellum, basal ganglia and other important partners of the cortex. But ‘walk before we run'; they are a great start to a more realistic understanding.

 

ResearchBlogging.org

Wedeen VJ, Rosene DL, Wang R, Dai G, Mortazavi F, Hagmann P, Kaas JH, & Tseng WY (2012). The geometric structure of the brain fiber pathways. Science (New York, N.Y.), 335 (6076), 1628-34 PMID: 22461612

G. Zamora-Lopez, C. Zhou, & J. Kurths (2011). Exploring brain function from anatomical connectivity Fronteirs in Neuroscience, 5 DOI: 10.3389/fnins.2011.00083