research – Page 4 – Replicated Typo

Some Links #16: Why I want to Falcon Punch (some) BBC Science Writers

I’m not normally one for violent resolutions to sloppy science, but in taking inspiration from one such perpetrator I’m promoting a Falcon Punch policy. Above is a graphical example of a successful Falcon Punch: the goal being to hurl your target onwards and upwards into a flaming ball of scientific shame.

Space is the final frontier for evolution, study claims. I had planned on writing a more substantial article on how yet another science writer, in this case one Howard Falcon-Lang, is claiming that Darwin has once again been felled by a new study. Greg Laden, however, beat me to the punch with a damning critique:

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Specific Language Impairment, Autism and Language Evolution

My last post speculated about what some conditions which manifest impaired theory of mind could tell us about the evolution of ToM. Of these conditions autism was one which could be the most informative when it comes to looking at the genetics of how ToM evolved, in this post I will look at what autism could tell us, not only about theory of mind, but also about other aspects of the language faculty.

Dorothy Bishop has recently written a paper exploring the above average co-occurrence of Specific Language Impariment (SLI) and Autistic Spectrum Disorders (ASD).

SLI is a condition where a child fails to develop spoken language on the normal schedule, for no observable or obvious reason (Bishop and Norbury 2008). Whilst ASD and SLI are regarded as distinct conditions, these disorders co-occur at above chance levels.

Bishop (2010) explores why this might be. Bishop begins her paper by painting a textbook example of a child with SLI. This example is of a child with normal social interaction and nonverbal communication, but with specific difficulties in mastering structural aspects of language, especially syntax and phonological skills. So this typical picture is not one of an autistic child in that one of the defining features of autism is a limited capacity for normal social interaction and a child is much more likely to be deficient in pragmatic skills than syntactic or phonological skills.

Bishop states that despite the fact that according to conventional diagnostic frameworks, SLI andASD are mutually exclusive diagnoses, similarities exist between the two conditions and these include:

They are both highly heritable
Identical, monozygotic twins are significantly more concordant than fraternal, dizygotic twins for autism and SLI
In both conditions rates of impairment in first degree relatives are higher than in the general population
First degree relatives of affected individuals of both conditions often manifest sub-threshold symptoms
These conditions correspond to points on a continuum of impairment, rather than all-or-none diseases

So any model of causation for either condition must take into account the following considerations:

Above chance levels of comorbidity between SLI and ASD
Rates of language impairment in relatives of probands with SLI and ASD
Molecular genetic findings of shared genetic risk factors for ASD and SLI

Now the article goes on to explore etiological models which explain these considerations with varying degrees of success. I’m not going to pretend to understand these models as I have only ever been formally taught in linguistics and so I’m a bit stumped by genetic psychology. If you’re much smarter than me you can read the article yourself here:

http://www.springerlink.com/content/gg087q4h51j5127g/fulltext.pdf

So what I got from this article was that the genetic factors involved in autism can not only cause the characteristics typical of a person with autism (pragmatic impairments) but also other language impairments which are typical of a person with a Specific Language Impairment. Specifically the CNTNAP2 gene has been found in independent samples to be associated with both ASD and SLI. This is interesting because it could show that gene mutations which cause improved social abilities could have also caused changes in our linguistic ability on a syntactic or phonological level.

Disclaimer: Sorry if I’ve made too many assumptions in the conclusion I’ve just drawn. As I said above I know next to nothing about genetic psychology but I just felt this research would have interesting consequences in the field of language evolution. I’d love to hear the thoughts of people who know better than I do.

References

Bishop, DVM. (2010) Overlaps Between Autism and Language Impairment:
Phenomimicry or Shared Etiology? Behavior Genetics 40:5, 618-629

Bishop DVM, Norbury CF (2008) Speech and language disorders. In: Rutter M, Bishop DVM, Pine D, Scott S, Stevenson J, Taylor E, Thapar A (eds) Rutter’s child

Theory of Mind and Language Evolution; What can psychopathology tell us?

Theory of Mind is the ability to infer other persons’ mental states and emotions. It is thought to have evolved as part of the human’s social brain and probably emerged as an adaptive response to increasingly complex primate social interaction.

Brüne and Brüne-Cohrs (2006) explore the ‘evolutionary cost’ of language evolution:

This sophisticated ‘metacognitive’ ability comes at an evolutionary cost, reflected in a broad spectrum of psychopathological conditions. Extensive research into autistic spectrum disorders has revealed that theory of mind may be selectively impaired, leaving other cognitive faculties intact. Recent studies have shown that observed deficits in theory of mind task performance are part of a broad range of symptoms in schizophrenia, bipolar affective disorder, some forms of dementia, ‘psychopathy’ and in other psychiatric disorders.

Now it’s fairly uncontroversial to assert that without the ability of theory of mind humans would have never evolved language (Sperber and Wilson, 2002). This is due to the fact that if one can’t attribute another to have a ‘mind’ like ones own, or assume that other minds hold different information to ones own then one would see little point in trying to share information. (I’m sorry for the amount of ‘ones’ in that sentence).

Sooo, it does not seem presumptuous to assume that people interested in the evolution of language should be interested in theory of mind, in fact for many years evolutionary linguists, psychologists and biologists have been looking into this, but mostly through observing the behaviour of animals, and especially primates to see if they display theory of mind capabilities. A good summary of this work can be found here, and a lot of relevant studies can be found on this blog in the What makes humans unique? posts by Michael. I’m not going to look at the animal data in this post, but instead what the deficiencies in some human conditions can tell us about the evolution of theory of mind. That is, what can autism, schizophrenia, bipolar affective disorder, dementia, ‘psychopathy’ and other psychiatric disorders tell us?

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Evolution of Colour Terms: 6 Categorisation Constraints

Continuing my series on the Evolution of Colour terms, this post reviews evidence for categorisation constraints on colour perception. For the full dissertation and for references, go here.

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Some Links #15: Empires of the Word & anti-Babel

Empires of the Word & anti-Babel. It’s a few days old now but I’ve only just had time to read it. Anyway, check out Razib’s review of Empires of the Word: A Language History of the world. Lots of information for budding historical linguists and those intrigued by language spread and extinction. Particularly relevant is the following paragraph:

As I indicated above Empires of the Word is rather thin on robust generalizations. But one point which the author mentions repeatedly is that the rise and fall of languages of great expanse and utility is the norm, not the exception. In particular, Nicholas Ostler takes time out to emphasize that languages which spread via trade often do not have long term staying power. Portuguese, Aramaic, Punic and Sogdian would fall into this category (the later success of Portuguese was a matter of rice and empire in Brazil). It seems that mercantile communities are too ephemeral, that successive historical shocks inevitably result in their decline when there isn’t a peasant demographic reservoir or imperial power which imposes it by fiat. Even those languages which eventually spread beyond traders and gain cultural and political cachet may fall from grace. Greek is the best case of this. It was the dominant language of the Roman East, and spoken as far as modern Pakistan, and studied in Dark Age Ireland. By the early modern period it was a strange and foreign language in the West, and with the rise of Islam in the east it lost its cultural glamor, and even those Christians in Arab lands who were Melkite, Greek Orthodox who adhered to the theological position of Constantinople, became Arab in speech and identity (in greater Syria the Greek Orthodox have been instrumental in the formulation of Arab nationalism).

Opening a bibliography database for human evolution. Again, it’s been a few days since this was posted, but I’d advise anyone interested in human evolution visit John Hawks recently announced database. The bibliography section also has an RSS feed which provides a chronological list (newest first).

In which I apply for a job as a homeopath… Dave over at Anomalous Disaster has a great little post on him applying for a position at NHS Tayside for a homeopathic specialist. This is from the very same health board who recently brought us the sacking of 500 staff. So Dave decided to apply, which, at a cushy £68,000 salary, is definitely a job worth pursuing — after all, it can’t be that hard to dispense magic beans and provide a pseudo-scientific air of authority. Here is part of his letter of application:

The original research that I have published means that I am familiar with the body of published work on homeopathy, and the many meta-analyses and systematic reviews conducted on it. The fact that these conclude that homeopathy is no more effective than a similarly administered placebo will not bother me whilst I am taking advantage of some of the excellent salmon fishing to be found in the Tayside region. Indeed, given the fact the position only calls for the successful applicant to attend two sessions per week, I should imagine I would have plenty of time to indulge in a bit of fishing.

Click here to apply.

Selfish Sounds: Darwinism in linguistics. A brief(ish) article on the work of historical linguist, Nikolaus Ritt, and how words and sounds compete for the purpose of being replicated. Specifically, it looks at how the sound shapes of English words have gradually evolved:

Good examples of such phenomena are sets of changes which are obviously directed but unfold over time spans that are impossible to even survey by individual speakers. They have come to be known as ‘drifts’. A case of such a drift seems to have affected the sound shapes of English words (or better: lexical morphemes, i.e. the smallest linguistic units that carry meaning). Over time their shapes seem to have gradually evolved in a direction where they came to fit better into the rhythmical patterning that characterises English speech. “For instance, vowels in long words tended to be shortened over time, while vowels in short words tended to be lengthened. Thus, the rhythmic units they established became more uniform”, Nikolaus Ritt explains.

[…] From the evolutionary perspective this kind of development is best understood if one regards rhythm as an environmental constant in the linguistic world in which words and the sounds they are made up of have to survive and replicate. Because of the constant environmental pressure which rhythm exerts on them, the sound shapes of English words have gradually changed to become better adapted to the rhythmically structured utterances through which they get expressed and transmitted.

Metroculturalism

Searching Research Blogging for “bilingualism”, two blogs dominate the recent posts: mine and Language on the Move – a blog started by Ingrid Piller and Kimie Takahashi at Macquarie University, Sydney, Australia. Since starting last year, they have been joined by a host of international collaborators. It’s a really well organised blog – they even have separate facebook and twitter officers!

The blog discusses topics on language learning, multilingualism and multicultural sociolinguistics. The writers are bilingual and certainly pro-bilingualism, but it’s good to see a genuine debate over the so-called ‘bilingual edge’ (see Piller 2010- a review of ‘the bilingual edge’ which argues that differences elicited in controlled conditions don’t necessarily translate to the real world where variables are correlated).

There’s been a recent spurt of posts and publications aimed at trying to get people out of a mono-mindset. Alastair Pennycook writes about Metrolingualism (see also, Otsuji & Pennycook, 2010) – the common use of many languages to construct identity. He reminds us that people are most cultural traits are not mutually exclusive. Indeed, the majority of people can communicate in many mediums. Despite this, there is a tendency both in research and general opinion to see monolingualism as the norm and bilingualism as exceptional.

As I have mentioned elsewhere, the monolingual mindset extends into computational modelling of language acquisition and evolution. Often, there are implicit monolingual assumptions. On the other hand, whole paradigms such as Steels & Belpeame’s ‘Naming Game’ focus on how populations of agents can arrive at the same, single mapping between words and meanings.

In fact, there is much evidence to suggest that children can acquire multiple languages easily. My own research focusses on a simple question – why did we evolve to be able to learn multiple languages? It would be more efficient to have a single human language – especially if it were innately specified. Instead, we have a culturally transmitted system that exhibits a large amount of variation.

I’m looking at two possible answers: Either there is no selective pressure on language and bilingualism is the product of historical accident (drift) or there is an inherent advantage to the flexibility that bilingualism affords, both for communication and for the evolvability of the system. Along the way, I’m hoping to look at whether monolingualism is a legitimate abstraction, or whether bilingualism is a fundamental part of language (for a recent talk, see here).

However, Pennycook points out the paradox of a monolingual mindset in a pervasively bilingual world, suggesting that it may be a political affliction rather than a scientific approach:
“If we take the current sociolinguistic literature on styles, registers, discourses, genres and practices seriously, then monolingualism is also a myth: a monolingual mindset does not emerge from a state of monolingualism, because no such state can exist. If languages are myths, so too is monolingualism!”

Piller, I. (2010). The bilingual edge: why, when, and how to teach your child a second language International Journal of Bilingual Education and Bilingualism, 13 (1), 115-118 DOI: 10.1080/13670050802645942

Otsuji, E., & Pennycook, A. (2010). Metrolingualism: fixity, fluidity and language in flux International Journal of Multilingualism, 7 (3), 240-254 DOI: 10.1080/14790710903414331

Marc Hauser investigated for scientific misconduct

The Boston Globe reported today that Marc Hauser is on leave due to scientific misconduct . The Great Beyond summarises the article as follows:

The trouble centers on a 2002 paper published in the journal Cognition (subscription required). Hauser was the first author on the paper, which found that cotton-top tamarins are able to learn patterns – previously thought to be an important step in language acquisition. The paper has been retracted, for reasons which are reportedly unclear even to the journal’s editor, Gerry Altmann.

Two other papers, a 2007 article in Proceedings of the Royal Society B and a 2007 Science paper, were also flagged for investigation. A correction has been published on the first, and Science is now looking into concerns about the second. And the Globe article highlights other controversies, including a 2001 paper in the American Journal of Primatology, which has not been retracted although Hauser himself later said he was unable to replicate the results. Findings in a 1995 PNAS paper were also questioned by an outside researcher, Gordon Gallup of the State University of New York at Albany, who reviewed the original data and said he found “not a thread of compelling evidence” to support the paper’s conclusions.

Hauser has taken a year-long leave from the university.

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Some Links #14: Can Robots create their own language?

Can Robots create their own language? Sean already mentioned this in the comments for a previous post. But as I’m a big fan of Luc Steels‘ work this video may as well go on the front page:

Speaking in Tones: Music and Language Partner in the brain. The first of two really good articles in Scientific American. As you can guess by the title, this article is looking at current research into the links between music and language, such as the overlap in brain circuitry, how prosodic qualities of speech are vital in language development, and the way in which a person hears a set of musical notes may be affected by their native language. Sadly, the article is behind a paywall, so unless you have a subscription you’ll only get to read the first few paragraphs, plus the one I’m about to quote:

In a 2007 investigation neuroscientists Patrick Wong and Nina Kraus, along with their colleagues at Northwestern University, exposed English speakers to Mandarin speech sounds and measured the electrical responses in the auditory brain stem using electrodes placed on the scalp. The responses to Mandarin were stronger among participants who had received musical training — and the earlier they had begun training and the longer they had continued training, the stronger the activity in these brain areas.

Carried to extremes: How quirks of perception drive the evolution of species. In the second good article, which by the way is free to view, Ramachandran and Ramachandran propose another mechanism of evolution in regards to perception:

Our hypothesis involves the unintended consequences of aesthetic and perceptual laws that evolved to help creatures quickly identify what in their surroundings is useful (food and potential mates) and what constitutes a threat (environment dangers and predators). We believe that these laws indirectly drive many aspects of the evolution of animals’ shape, size and coloration.

It’s important to note that they are not arguing against natural selection; rather, they are simply offering an addition force that guides the evolution of a species. It’s quite interesting, even if I’m not completely convinced by their hypothesis — but my criticisms can wait until they publish an actual academic paper on the subject.

A robotic model of the human vocal tract? Talking Brains links to the Anthropomorphic Talking Robot developed at Waseda University. Apparently it can produce some vowels. Here is a picture of the device (which looks like some sort of battle drone):

Y Chromosome II: What is its structure? Be sure to check out the new contributor over at GNXP, Kele Cable, and her article on the structure of the Y Chromosome. I found this sentence particularly amusing:

As you can see in Figure 1, the Y chromosome (on the right) is puny and diminutive. It really is kind of pathetic once you look at it.

Scientopia. A cool collection of bloggers have banded together to form Scientopia. With plenty of articles having already appeared it all looks very promising. In truth, it’s probably not going to be as successful as ScienceBlogs, largely because it doesn’t pay contributors and, well, nothing is ever going to be as big as ScienceBlogs was at its peak. This new ecology of the science blogosphere is well articulated in a long post by Bora over at A Blog Around the Clock.

Language evolution in the laboratory

When talking about language evolution there’s always a resistance from people exclaiming; ‘but how do we know?’, ‘surely all of this is conjecture!’ and, because of this, ‘what’s the point?’

Thomas Scott-Phillips and Simon Kirby have written a new article (in press) in ‘Trends in Cognitive Science’ which addresses some of the techniques currently used to address language evolution using experiments in the laboratory.

The Problem of language evolution

The problem of language evolution is one which encompasses not only the need to explain biologically how language came about but also how language came to be how it is today through processes of cultural evolution. Because of this potential ambiguity arises when using the term ‘language evolution’. To sort this ambiguity the authors put forward the following:

Language evolution researchers are interested in the processes that led to a qualitative change from a non-linguistic state to a linguistic one. In other words, language evolution is concerned with the emergence of language

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Culture-driven population dynamics: sustainable or unsustainable?

When looking at culture-driven population dynamics, a common assumption is that there’s a positive feedback between cultural evolution and demographic growth. The general prediction, then, is for unlimited growth in population and culture. Yet models based on these assumptions tend to ignore important aspects of cultural evolution, namely: (1) cultural transmission is not perfect; (2) culture does not always promote population growth. Ghirlanda et al (2010) incorporate these two features into a model, and arrive at some interesting conclusions. In particular, they argue those populations maintaining large amounts of culture may run the risk of extinction rather than stability or growth.

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