Waarom kunnen sommige mensen niet dansen? [Dutch]

Het Amsterdam Dance Event is begonnen. Waarom kunnen sommige mensen niet dansen? 

Een gesprek met neurowetenschapper Fleur Bouwer van de Universiteit van Amsterdam. De aflevering is hier te vinden. 

What do we share with other primates in terms of cognition?

Below a beautiful summary of the recent literature on the neurobiology of action imitation/understanding, language, and rhythmic processing/auditory timing (Mendoza & Merchant, in press). The neural circuitry that is thought to be involved in all three higher cognitive functions is shown here for three closely related primates: the macaque monkey, chimpanzee and human brain.

Schematic representation of the neural circuits for action imitation/understanding, language, and rhythmic processing in three closely related primates. Upper, middle and lower panels adapted from Hecht et al. (2013a), Rilling et al. (2008) and Merchant and Honing (2014), respectively.
(In turn, adapted from Mendoza & Merchant, in press.)

For me, and several other researchers in the field of rhythm cognition, the bottom panel is the most intriguing. It addresses the question in how far we share rhythm cognition with other primates.

Quite a few papers on this topic came out recently (I cite a small selection below). One of the teasing questions is the absence/presence of a bidirectional link between IPL (inferior parietal lobe) and MPC (medial premotor cortex), a link that quite a few researchers suspect is crucial to regularity detection or rhythmic entrainment in sound and music, and arguably should be considered a basic building block of musicality.

Ackermann, H., et al. (2014, in press). Brain mechanisms of acoustic communication in humans and nonhuman primates: An evolutionary perspective. Behavioral and Brain Science.

Honing, H., & Merchant, H. (2014, in press). Differences in auditory timing between human and non-human primates. Behavioral and Brain Science.

Mendoza, G., Merchant, H. (2014). Motor system evolution and the emergence of high cognitive functions Progress in Neurobiology DOI: 10.1016/j.pneurobio.2014.09.001
 
Merchant, H., & Honing, H. (2014; online). Are non-human primates capable of rhythmic entrainment? Evidence for the gradual audiomotor evolution hypothesis. Frontiers in Neuroscience, 7 (274) 1-8. doi 10.3389/fnins.2013.00274

 Patel, A., & Iversen, J. (2014). The evolutionary neuroscience of musical beat perception: the Action Simulation for Auditory Prediction (ASAP) hypothesis Frontiers in Systems Neuroscience, 8 DOI: 10.3389/fnsys.2014.00057

Is beat induction innate or learned?

This week a short entry with a selection of discussions related to the newborn study mentioned in last months entry.

• Discussion at ScienceNews by Bruce Bower.
  
• Discussion at Wired by Brandon Keim.
  
• Interview at WNYC Public Radio by John Schaefer: [soundfile]
• Report by Science Update by Bob Hirshon: [soundfile]
• Report by NewScientist by Hazel Muir, video by Sandrine Ceurstemont:
  

For more media attention see Google news.

Winkler, I., Haden, G., Ladinig, O., Sziller, I., & Honing, H. (2009). Newborn infants detect the beat in music Proceedings of the National Academy of Sciences, 106 (7), 2468-2471 DOI: 10.1073/pnas.0809035106

Do infants prefer music over speech?

In this weeks online edition of PNAS Marcel Zentner and Tuomas Eerola report on a study in which they carried out two experiments with a total of 120 infants, aged between 5 and 24 months. The infants were exposed to various musical and rhythmic stimuli, including isochronous drumbeats. Control stimuli consisted of adult- and infant-directed speech. The researchers could show that infants engage significantly more in rhythmic movement to music, and other rhythmically regular sounds, than to speech. The findings are suggestive of a predisposition for rhythmic movement in response to music and other metrically regular sounds. The study also adds to the existing evidence that infants have a liking and preference for rhythmical music from day one, a predisposition that preceeds language.

Zentner, M., & Eerola, T. (2010). Rhythmic engagement with music in infancy Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1000121107

Are auditory representations a result of temporal predictions?

Last month an interesting review was published in the journal Trends in Cognitive Sciences arguing that ‘predictive representations of temporal regularities constitute the core of auditory objects in the brain.’ A possible consequence of this argument is that auditory sensory memory and (temporal) predictions are simply two sides of the same coin.

The authors (among which István Winkler and Sue Denham that collaborated with our Amsterdam group in the EmCAP project; see earlier blogs), review much of the recent literature using brain imaging and electrophysiological techniques. They support their hypothesis on the basis of at least five observations (and I paraphrase the authors here):

First, auditory regularity representations are temporally persistent; they have been shown to connect sounds separated by up to circa 10 seconds and persist for at least 30 seconds.

Second, auditory regularity representations encode all sound features with a resolution comparable to perception, since perceptually discriminable deviations elicit a Mismatch Negativity (MMN).

Third, when two sound streams are perceptually separated, MMN reflects the perceived sound organization, its elicitation dynamically follows perceptual fluctuations between two alternative sound organizations and the effects of priming sequences on perception.

Fourth, regularities are extracted from acoustically widely different exemplars in a sequence, including the natural variation of environmental sounds.

And finally, violations of predictive rules have been shown to elicit the MMN. For example, delivering a low tone after a short one elicited the MMN, when for most tones the rule “short tones are followed by high-pitched tones, long tones by low-pitched tones” held.

Interestingly, violations in the form of silence (i.e. no sound) - such as omissions in a natural drum-pattern - also show a MMN. And in addition, these effects are also found when attention is directed to other aspects than the sound /music or when participants are unattentive (such as in the case with sleeping neonates).

Winkler, I., Denham, S., & Nelken, I. (2009). Modeling the auditory scene: predictive regularity representations and perceptual objects Trends in Cognitive Sciences, 13 (12), 532-540 DOI: 10.1016/j.tics.2009.09.003

Do newborn infants have a sense of rhythm?

[Report related to PNAS Early Edition]

It might look somewhat disturbing, but the picture that accompanies this entry is a snapshot of a two day old baby that is healthy and sound asleep! She is one of fourteen newborns that participated in a recent listening experiment, a collaboration between the Institute for Psychology of the Hungarian Academy of Sciences and our research group at the University of Amsterdam in the Netherlands. In this project we are interested in how newborn infants perceive the musical world around them and in how far certain musical skills are innate.

We know that newborn infants are sensitive to a variety of sounds. But what do they factually hear? Can they make sense of the musical world around them? Do they have a sense of rhythm, arguably one of the fundaments of music?

To study this, we collaborated with a research group in Budapest, Hungary lead by István Winkler, a specialist in auditory perception and one of the pioneers in measuring brain activity in neonates.

Since the start of this European research project (named EmCAP) we talked a lot about how we could take advantage of existing theories in music cognition to study auditory perception in newborn infants, and how to probe their (potential) sense of rhythm. After many pilot studies, and resolving quite a few methodological issues that come with doing experiments with neonates, in the end we opted to use a simple, regular rock rhythm, consisting of hi-hat, snare, and bass drum (see below). We made several variants of this rock rhythm by omitting strokes on non-significant metrical positions (i.e. non-syncopated rhythms in music theoretical terms). We then inserted, once in a while, a 'deviant' segment: the same rhythm but with a missing ‘downbeat’ (i.e. a syncopated rhythm). The result sounded like this [click on the play button; to stop, click again]:

Since it is quite difficult to observe behavioral reactions in newborns a small number of electrodes were carefully glued to the scalp and face of the newborns to be able to measure their electrical brain signals (see photo). N.B. The baby’s were fed just before the measurements with their mother being present during the whole session that lasted twenty minutes.

What did the experiment reveal? Well, shortly after each ‘deviant’ segment began, the babies' brains produced an electrical response indicating that they had expected to hear the downbeat but had not. As such we could show that newborn infants can detect the beat in music (The results will be published this week in PNAS Early Edition).

What are the potential implications of these findings? For me, one of the most important realizations is that a cognitive skill called beat induction, which most of us think of as trivial (e.g., being able to tap your foot to the beat), is active so early in life. It can be seen as additional support for the idea that, beat perception contributed to the origins of music since it enabling such actions as clapping, making music together and dancing to a rhythm. Next to being music-specific, beat induction is also considered to be uniquely human. Even our closest evolutionary relatives, such as the chimpanzee and bonobo, do not synchronize their behavior to rhythmic sounds. This makes the topic of beat induction a fundamental issue in current music cognition research (see, e.g., Patel, 2008:402).

Furthermore, the results challenge some earlier assumptions that beat induction is learned in the first few months of life, for example by parents rocking the infant. Our study suggests that beat perception must be either innate or learned in the womb (as the auditory system is at least partly functional as of approximately three month before birth).

Finally, it should be noted that the auditory capabilities underlying beat induction are also necessary for bootstrapping communication by sounds, allowing infants to adapt to the rhythm of the caretaker’s speech and to find out when to respond to it or to interject their own vocalization. Therefore, although these results are compatible with the notion of the genetic origin of music in humans, they do not provide the final answer in this longstanding debate.

István Winkler, Gábor P. Háden, Olivia Ladinig, István Sziller, Henkjan Honing (2009). Newborn infants detect the beat in music. Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.0809035106

Can newborns make sense of rhythm? (Part 2)

In search of the origins of music perception, our European research consortium (named EmCAP) investigates questions such as whether or not newborns possess the ability to process music. However, while we all intuitively feel that babies like rhythms and melodies, we don’t know how they perceive music. This week the MTAPI team started a first series of experiments to test whether rhythm and meter perception is active in newborn infants.

Our hypothesis is that a rhythmic stimulus (we use a simple drum pattern), when occasionally modified in two distinct metrical positions (a temporal oddball), should be perceived more easily as a deviation if the modification happens in a metrically strong position as compared to one in a weaker metrical position, as such indicating that a metrical expectation is active. These so-called oddballs are expected to elicit the mismatch negativity (MMN) event related brain potential (ERP), a well-known response that is elicited by violations of a detected acoustic regularity.

One of the reasons this particular method was chosen was that it allows us to use the same technique and the same rhythmic stimuli for both adult non-musicians and newborn infants. The preliminary results confirm the hypothesis for adults. Needless to say we are more than curious for what the newborn study will show us. We hope to present the first results at the upcoming Neurosciences and Music conference in Montreal this summer.

Honing, H., Ladinig, O., Winkler, I., Haden, G. (in press) Probing emergent meter perception in adults (and newborns) using event-related brain potentials: a pilot study. Proceedings of the Neurosciences and music III Conference. Montreal: McGill University.

A sense for rhythm? (Part 3)

Last week quite a few people participated in an informal listening test on rhythm. It gratefully used some of the stimuli from a study by Hannon and Trehub (H&T).*

H&T studied the sensitivity of listeners to detect violations of rhythmic structure in simple meters (i.e. duple and triple meter; such as a march or waltz) and more complex meters (i.e. compound meter, such as 5/8 and 7/8, common to, e.g., Balkan music).
N.B. Last week’s fragment 1 was an example of a stimulus in a simple meter, fragment 2 was one in a complex meter (see earlier blog).

H&Ts study showed that North American participants judged the structure-violating music examples (e.g., the A-fragments in last weeks blog) as less similar to the original version than the structure-preserving ones (e.g., the B-fragments), but only so for the examples is simple meter (Fragment 1 in the earlier blog).

In a second experiment they showed that participants of Bulgarian or Macedonian origin could spot the rhythmic violations in both complex and simple-meter contexts. Arguably, because complex meters are more common in Balkan music. As such this is evidence for an effect of exposure or enculturation on rhythmic sensitivity. (Interestingly, the readers who did the test last week, performed quite similar to the Bulgarian participant group; But note: we did not replicate the study last week, it was just a demonstration).

An additional surprise of the H&T study was that 6-month-old infants (from North American origin), when exposed to the same stimuli, did as well in both metrical contexts: so very much like the Bulgarian adults. This is support for the idea that a sensitivity for rhythm and meter is actually active at an early age, and hinting that the North American participants lost some of these capabilities, instead of Balkan participants learning them. Of course, further research is needed to substantiate this, but the study is intriguing on its own.

Hannon, E.E., Trehub, S.E. (2005). Metrical Categories in Infancy and Adulthood. Psychological Science, 16(1), 48-55. DOI: 10.1111/j.0956-7976.2005.00779.x

A sense for rhythm? (Part 2)

This week an informal listening test that might reveal something about your sense for rhythm. If you have a minute to spare, please continue reading and respond to the three questions below. The outcome might surprise you!

First, state whether you consider yourself having a sense for rhythm (N.B. you can be honest, the responses are recorded anonymously):


Then do the following two comparisons. First, listen to the following folksong (Fragment 1):

Fragment 1

Then compare Fragment 1A and 1B to 1, and decide which of the two is rhythmically dissimilar:

Fragment 1A
Fragment 1B

Then listen to Fragment 2:

Fragment 2
And finally, compare Fragment 2A and 2B to 2, and decide which of the two is rhythmically dissimilar?

Fragment 2A
Fragment 2B

These examples are taken from a study by Hannon and Trehub published in Psychological Science.* There is at least one surprising results presented in that study. For now, please do the informal experiment, and I will tell more about the results next week. [see here]

Erin E. Hannon, Sandra E. Trehub (2005) Metrical Categories in Infancy and Adulthood. Psychological Science 16 (1), 48–55. DOI: 10.1111/j.0956-7976.2005.00779.x

A sense for rhythm? (Part 3)

Last Monday, together with four colleagues from the University of Amsterdam, I was asked to speak at the Opening of the Academic Year.

I started with talking about a wonderful study by Erin Hannon and Sandra Trehub (University of Cornell and University of Toronto) called "Metrical Categories in Infancy and Adulthood", and gratefully used some of the sound examples they made available online.

Interestingly, a "one-trial" version of their experiment failed miserably :-) The sign language interpreter picked up the differences immediately and communicated them so clearly to the audience that I had to ask the audience to close their eyes for the other sound examples!

The overall message was, motivated by e.g. the Hannon & Trehub study: Listen as often and as varied as you can, it will improve your sense for rhythm!

Can newborns make sense of rhythm?

Last month our research group organized the annual EmCAP workshop in Amsterdam: A consortium of four European universities that collaborate in trying to understand how cognition might emerge in active perception. Or, in other words, how we accumulate knowledge in the world by actively being engaged with it. Music was chosen as the ideal domain to figure that out.

One of the big challenges of this project is to see whether, and if so to what extent, newborns have musical capabilities, and how exposure to music allows cognitive constructs like harmony or meter to emerge. More and more studies show that even a few month old babies have all kinds of perceptual and musical skills that allow them, for instance, to note the difference between violations in complex Balkan rhythms and (for us) more straightforward western rhythms, a difference that adult listeners, in general, find difficult to notice.

In the EmCAP project, in collaboration with the Bulgarian baby-lab, we planned to start this spring to have newborns —like those in the picture above—listen to syncopated and non-syncopated rhythms as a way to find out whether they are sensitive to the concept of meter as an emergent property. Something that could, alternatively, well be simply a learned music theoretical and/or cultural concept. We hope to find out ...