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Yes, now it’s out as a second edition. The big cognitive neuroscience textbook entitled “Cognition, Brain and Consciousness” is edited by Bernard J. Baars and Nicole Gage, and has already received good reviews, among one prominent and positive review in Nature Neuroscience. (Both my chapters survived the revision process, with minor changes.)

I’ve been using this book for courses with around 200 students with great success. It has been entertaining, and most wonderful to use (inspiring to students both with regard to text and graphics).

I’d recommend the book to anybody with a keen interest in cognitive neuroscience, ranging from new students to the field, to researchers (like me) who want to catch up on how cognitive neuroscience is being taught, and what’s considered “standard knowledge” outside my own domain of research.

Patricia Churchland’s review puts it right:

“Masterfully organized and comprehensive in its coverage, this textbook will surely be THE introduction to cognitive neuroscience. The contributing authors are highly accomplished experts, and details are deftly selected to illustrate principles as well as to launch the curious reader into the exciting but vast realm of the nervous system. Anatomy, sometimes the bane of introductions to the brain, is gracefully interwoven on a need-to-know basis. In a clever use of IT, the accompanying website provides videos of human patients as well as powerpoint slides for anatomy and physiology. The companion website will be updated regularly with the latest results, and in the open-source tradition, website ideas are solicited from imaginative readers. A powerful pedagogical achievement, and a boon for both the novice and the advanced student.”

Book description

This is the fully revised and updated second edition of the very sucessful introductory textbook on cognitive neuroscience. Written by two leading experts in the field, this textbook book takes a unique thematic approach to introduce concepts of cognitive neurosciences, guiding students along a clear path to understand the latest findings whether or not they have a background in neuroscience. New to this edition are Frontiers in Cognitive Neuroscience text boxes; each one focuses on a leading researcher and their topic of expertise. There is a new chapter on Genes and Molecules of Cognition, and all other chapters have been thoroughly revised, based on the most recent discoveries.

Contents

1 Mind and brain
2 A framework
3 Neurons and their connections
4 The tools: Imaging the living brain
5 The brain
6 Vision
7 Hearing and speech
8 Attention and consciousness
9 Learning and memory
10 Thinking and problem-solving
11 Language
12 Goals, executive control, and action
13 Emotion
14 Social cognition: Perceiving the mental states of others
15 Development
16 The genes and molecules of cognition
Appendix 1

– Thomas

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The recent issue of the journal Hippocampus has an interesting article on the structure of the hippocampus throughout the menstrual cycle. By studying women two times during the menstrual cycle (pre- and post-menstrual) using volumetric MR scanning, researchers Xenia Protopopescu and her colleagues at Cornell University demonstrated structural changes in the hippocampus. Specifically, gray matter was relatively increased in the right anterior hippocampus and relatively decreased in the right dorsal basal ganglia (globus pallidus/putamen) in the postmenstrual phase.

Below is an image from that article, showing a t-map rendering showing increased anterior hippocampus (yellow) and decreased basal ganglia (pink) in the postmenstrual vs. premenstrual phase. Seems to me that the entorhinal cortex was also affected

Correspondingly, verbal declarative memory changed throughout the cycle: memory performance increased in teh postmenstrual vs. premenstrual phase. These results support models of estrogen-dependent cyclical alterations in hippocampal synaptic density and function proposed to account for neuronal and cognitive differences seen across the menstrual cycle.

The basal ganglia findings were rather unexpected, and the researchers suggest that:

(…) estrogens have been shown to increase striatal dopamine release, to influence striatal serotonergic and dopaminergic innervation density, and to promote striatal medium size spiny neuronal maturation in vivo (Korol, 2004b). The apparent opposite effect of high estrogen levels on hippocampal and basal ganglia gray matter may relate to the finding in rats that high estrogen promotes use of a hippocampally-mediated spatial (place or allocentric) learning strategy, while low levels promote use of a nonhippocampal, possibly striatally-mediated navigational (response or egocentric) strategy (Korol, 2004b). In humans, MRI studies have shown that navigational ability correlates with level of activity in the basal ganglia (putamen) (Epstein et al., 2005), and more specifically, that navigation using a response strategy is associated both with greater activity (Iaria et al., 2003) and gray matter (Bohbot et al., 2007) in the basal ganglia (caudate), though it should be noted that menstrual cycle effects were not assessed in any of these studies.

I can imagine the jokes that may come out of this… but leave it for now 😀 One thing that strikes me is the question of how these changes are related to the menopause. For example, would these changes mean that intra-individual variation during the month would be reduced after the menopause? As one knows from ageing research, such variance increases with age. So it is even conceiveable that the development goes the opposite way.

I also notice that the same researchers have recently demonstrated a link between changes in orbitofrontal cortex and emotional processing. It’s also worth a read.

-Thomas

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After writing this weekend’s post on music (below) I got thinking that maybe I should consider updating my wildly popular post on bioaesthetics books – i.e. books looking at aesthetic phenomena from the point of view of biology. A couple of new titles have come out since I wrote that post back in 2006 so an update might be in order. While I ponder which books to include here’s a couple of snippets of news from the wacky world of neuroaesthetics.

Fist of all, it should be noted that Semir Zeki, a well-known neurophysiologist, recently was appointed the world’s first ever professor of neuroaesthetics. As far as I know this institutional break-through for neuroaesthetic came as a result of Zeki receiving, together with Ray Dolan, a Wellcome Trust “strategic award” of 1 million £ to search for “the neural and biological basis for creativity, beauty and love”. (See the press release at the Wellcome Trust’s homepage.) The cool one mil also means that Zeki is now hiring a research associate to work on neuroaesthetics. To celebrate his new position (or so I imagine!), in November he will publish his new book, entitled Splendour and Miseries of the Brain.

However, if you can’t wait until November you might want to visit Zeki’s new blog. Here, among other things you can read about recent neuroaesthetics events that Zeki has participated in, including a meeting in Berlin at May 8 inaugurating something called the Association of Neuroaesthetics (AoN). The AoN is the brainchild of Alexander Abbushi, a neurosurgeon at Berlin’s Charité Hospital. According to its mission statement,

It is the aim of the Association of Neuroesthetics, a European initiative originating at the Charité – Universitätsmedizin Berlin to bring together both the knowledge acquired and the methods employed by contemporary artists and neuroscientists in order to work towards a shared language. It is the Association’s hope that new artistic projects and new approaches in research and the arts may emerge that speak this new language.

Two symposia are planned for the years 2009 and 2010. As a new platform they are intended to allow artists, art historians, scholars in cultural studies, curators and neuroscientists to begin a productive dialogue. The following themes have been envisaged: “Color, Form and Light“, “Temporality, Ambiguity and Uncertainty” and “Subjective Mental States.” The results of these endeavours will be artistic projects, research publications and conference proceedings, all accessible to the public.

Apart from these two prospective meetings it is not clear from the homepage what AoN more precisely plans to do, although it seems very promising that they are already advertising for future Ph.D. students. That could indicate that the Charité intends to host more basic neuroaesthetics research. Let’s hope so.

Both Zeki’s professorship (and Wellcome’s funding) and the organizational initiative of AoN are great news. But what the field of neuroaesthetics is perhaps most in need of is a more institutionalized setting for disseminating and debating research. Of course, people working on empirically understanding the neural underpinnings of aesthetic behavior will attempt to publish their work in the most prestigeous neuroscience journals possible. However, it would be greatly beneficial to have a peer-reviewed journal dedicated to reviewing and discussing theories and new results. Also, at the moment many neuroaesthetics conferences put a premium on inviting big names to give the field some needed credibility, even when these researchers have no track history of actually conducting neuroaesthetic research. It would be enourmously helpful to the increasing maturation of neuroaesthetics as a bona fide research field if somebody were to host an annual or bi-annual conference focusing on the presentation of new data – with an open call for papers.

With these words let me as a final news flash be self-centered enough to mention an up-comming book simply entitled Neuroaesthetics, edited by yours truly together with my good friend Oshin Vartanian. Beside contributions by Oshin and myself it includes chapters by Thomas Jacobsen; Steven Brown and Ellen Dissanayake; Tecumseh Fitch, Antje von Graevenitz and Eric Nicolas; Marcos Nadal, Miquel Capó, Enric Munar, Gisèle Marty & Camilo José Cela-Conde; Anjan Chatterjee; Dahlia Zaidel; Nicholas Wade;Mari Tervaniemi; David Miall; Torben Grodal and Troy Chenier and Piotr Winkielman. In editing this book Oshin and I have attempted two things: First of all to present neuroaesthetics as a broad field incorporating all the arts and all questions of possible aesthetical interest. Secondly, we wanted to distinguish the most most pressing porblems facing the field in the hope of promoting new empirical research.

The book is still in production but it is already possible to go to the publisher’s homepage and order it now at a considerable discount. When I know more about the publication date I will get back to you with further details.

-Martin

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calvino.jpgI’ve just received a copy of Image, Eye and Art in Calvino, a new book on “the relationship between the visual and the textual” in Italo Calvino, edited by Birgitte Grundtvig, Martin McLaughlin, and Lene Waage Petersen. Together with Frederik Stjernfelt and Olaf B. Paulson I wrote a chapter for the book on the neurobiology of poetic imagination. A quick glance at the book reveals it to be full of other interesting papers as well!

On a somewhat different note, yesterday’s NY Times Magazine had a long article by Jeffrey Rosen on the relation between neuroscience and the law, a recurrent theme here on the blog. I haven’t had time to read it yet, but I will be back later this week with some comments.

-Martin

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images.jpgA new issue of Social Neuroscience is now out. It contains a discussion of Broca’s area in language and gesturing (or, meaningful behaviours); the phenomenon of what we can call “romantic love priming“; and what happens to performance and brain responses if you are socially excluded. These and more articles can be found here.

-Thomas

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This year it is 150 years ago that miners in the German Neander Valley lucked upon 16 fossils that turned out to belong to a different homo species. The Neanderthals are of special interest to the study of the homo sapiens brain, being bigger in average volume, but (presumably) different in function. Since brains doesn’t fossile there are really only two ways of studying this difference: (1) through comparing the DNA of the two species, and (2) through what has been called cognitive archeology – the deduction of how the Neanderthal mind must have been organized through an examination of archeological evidence such as diet, technology and social structure.

If you happen to read German this article in Die Zeit kicks off the Neanderthal year. In July Bonn will host a big conference on the Neanderthals. Its web-site has a number of interesting papers on-line.

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Mirror neurons

On a hot summer day 15 years ago in Parma, Italy, a monkey sat in a special laboratory chair waiting for researchers to return from lunch. Thin wires had been implanted in the region of its brain involved in planning and carrying out movements.

Every time the monkey grasped and moved an object, some cells in that brain region would fire, and a monitor would register a sound: brrrrrip, brrrrrip, brrrrrip.

A graduate student entered the lab with an ice cream cone in his hand. The monkey stared at him. Then, something amazing happened: when the student raised the cone to his lips, the monitor sounded – brrrrrip, brrrrrip, brrrrrip – even though the monkey had not moved but had simply observed the student grasping the cone and moving it to his mouth.

The researchers, led by Giacomo Rizzolatti, a neuroscientist at the University of Parma, had earlier noticed the same strange phenomenon with peanuts. The same brain cells fired when the monkey watched humans or other monkeys bring peanuts to their mouths as when the monkey itself brought a peanut to its mouth.

Later, the scientists found cells that fired when the monkey broke open a peanut or heard someone break a peanut. The same thing happened with bananas, raisins and all kinds of other objects.

“It took us several years to believe what we were seeing,” Dr. Rizzolatti said in a recent interview. The monkey brain contains a special class of cells, called mirror neurons, that fire when the animal sees or hears an action and when the animal carries out the same action on its own.

By now mirror neurons is a well-known story. However, if you are not up to speed Sandra Blakeslee has a nice story in NY Times giving a short run-down of the story so far. (The quote above is from that article.) Afterwards, you will probably enjoy a visit to the homepage of the Physiology Lab at Parma University. That’s the home of many of the pricipal investigators working on the mirror neuron cells, including Giacommo Rizzolatti, Leonardo Fogassi, and Vittorio Gallese. They have a lot of their research papers on-line.

I’m chiefly mentioning this because I’m going to put up the next installment in my little series on the neurobiology of culture in a few days. (See the first part here.) Here, mirror neurons play a vital part, and you may want to get a head start!

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Hardwired Behavior

This book from Cambridge University Press looks interesting. I haven’t actually read it yet, but the new issue of Nature has a rather positive review of it. A brief passage from the review:

Laurence Tancredi’s book Hardwired Behavior powerfully presents science that shows the gross inadequacy of the binary terms we often use to talk about the genesis and character of complex human behaviours. He writes: “Our brain structures are not immutable; they are susceptible to change for the better and change for the worse.” Indeed, much of the research he discusses rests on this neuroplasticity. He reports on research showing that talk therapy can produce neuronal changes. His chapter on gender differences suggests that changing social conceptions of the roles of women “will inevitably affect the biology of their brains over time”. He reports on research showing that rats deprived of nurture at birth fail to express a gene that is correlated with their ability to handle stress. And he refers several times to a fascinating study by Avshalom Caspi and colleagues (Science 301, 386–389; 2002), which found that the likelihood of children becoming antisocial as adults is a function of both their genomes and their experiences. As Tancredi observes, this finding “emphasizes the interactive nature of genes and environment, nature and nurture”.

Tancredei, L. (2005): Hardwired Behavior. What Neuroscience Reveals About Morality. Cambridge University Press.
Publisher’s description.

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Until recently anatomists were convinced that humans are born with all the neurons they are ever going to own. In the first years of life, some of theses neurons are then pruned due to a dynamic selection process. From then on, the only serious change to the brains was thought to come from cell death or inflicted lesions.

Not so. The brain actually continues to rebuild itself throughout life. For instance, new cells are born in the hippocampus. And a new study from a group at MIT demonstrates that adult dendrites of non-pymidal neurons are able to expand their branches. Here’s the abstract:

Despite decades of evidence for functional plasticity in the adult brain, the role of structural plasticity in its manifestation remains unclear. To examine the extent of neuronal remodeling that occurs in the brain on a day-to-day basis, we used a multiphoton-based microscopy system for chronic in vivo imaging and reconstruction of entire neurons in the superficial layers of the rodent cerebral cortex. Here we show the first unambiguous evidence (to our knowledge) of dendrite growth and remodeling in adult neurons. Over a period of months, neurons could be seen extending and retracting existing branches, and in rare cases adding new branch tips. Neurons exhibiting dynamic arbor rearrangements were GABA-positive non-pyramidal interneurons, while pyramidal cells remained stable. These results are consistent with the idea that dendritic structural remodeling is a substrate for adult plasticity and they suggest that circuit rearrangement in the adult cortex is restricted by cell type–specific rules.

The paper was published in PLoS Biology which means it is open-access. Go grap it!

Lee, WCA. et al. (2006): Dynamic remodeling of dendritic arbors in GABAergic interneurons of adult visual cortex. PLoS Biol 4(2): e29.

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The most recent issue of Nature Neuroscience contains a truly amazing study by the Thomas Insel-group. Insel and his colleagues have for many years studied pair-formation in prairie voles. Earlier, they have demonstrated that dopamine transmission within the nucleus accumbens (Nacc) facilitates partner-preference formation (i.e., that the infusion of dopamine into Nacc makes male pairie voles seek out female mates). In this new paper, they demonstrate that the rostal shell of Nacc actually contains two different dopaminergic receptors that perform functionally different jobs. One type, called D2, facilitates the approach behavior associated with the formation of a pair-bond. The other, D1, maintains that bond, by antagonizing the activity of the D2-receptors. This “faithfulness” is expressed behaviourally by the male voles figthing off other female voles than the partner. Crucially, D1-receptors are upregulated after the pair-bond has been formed. In other words: the male vole’s brain changes with having a relationship – it, figuratively speaking, becomes faithful. Thus, the behavioural process of finding a mate, establishing a relationship and keeping it going depends upon a complicated molecular process in parts of the prairie vole’s reward system. This result opens at least two exiting new avenues of ressearch: (1) Will we find the same functional system in the human brain? What is the genetic reason for a vole having more or less D1-receptors, i.e. being able to form long lasting pair-bonds?

I personally wouldn’t be surprised if Insel one day receives the Nobel prize. Being the director of NIMH shouldn’t hurt!

Aragona, B. et al. (2005): Nucleus accumbens dopamine differentially mediates the formation and maintenance of monogamous pair bonds. Nature Neuroscience 9: 133-139.

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