Monday, May 30, 2016

Interested in a PhD position at the UvA?

Recently new funds have been made available to the University of Amsterdam's Faculty of Humanities through the so-called Sustainable Humanities programme (Duurzame Geesteswetenschappen). The faculty has decided to dedicate part of the funds to creating five new PhD positions (4 years, 0.8 fte each).

Previous contact with the Faculty of Humanities or possible supervisors is not necessary. International researchers are also encouraged to apply. Proposed projects must be relevant to one of the research schools within AIHR or to ILLC (in the case of music cognition related proposals).

Applications should include a description of the proposed research project (max. 2500 words, written in English), a full academic CV, and a list of MA/MSc grades (see link below for more information). Applicants must have a completed Master’s degree in a relevant field before the start date of the fellowship.

See website for more information.

N.B. The deadline for applications is 15 August 2016.

Friday, May 20, 2016

Can birds perceive rhythmic patterns?

The specific question whether animals can detect regularity in a stimulus and synchronize their own behavior to arbitrary rhythmic patterns got sudden attention with the discovery of Snowball, a sulphur-crested cockatoo that could synchronize head and body movements with the beat in several popular songs (see earlier entry). Parrots, such as Snowball, are vocal learners and vocal learning is associated with evolutionary modifications to the basal ganglia, which play a key role in mediating a link between auditory input and motor output during learning. As such linkage between auditory and motor areas in the brain is also required for beat induction, Patel suggested that only vocal learning species might be able to show beat induction. However, further studies have shown the picture to be more complicated (see earlier entry) and this calls for a re-examination of the link between vocal learning and beat perception and induction. While zebra finches (vocal learners) are able to discriminate a regular isochronous from an irregular stimulus (Van der Aa et al., 2015), this discrimination was strongly reduced with tempo transformations (changing rate, but not the regularity of the stimulus). Zebra finches seem to attend strongly to specific local features of the individual stimuli (e.g. the exact duration of time intervals) rather than the overall regularity of the stimuli, which was the main feature human listeners attended to (Van der Aa et al., 2015).

Figure 3 from Ten Cate et al. (2016)
In a recent paper (Ten Cate et al., 2016) we review the available experimental evidence for the perception of regularity and rhythms by birds, like the ability to distinguish regular from irregular stimuli over tempo transformations and report data from new experiments. While some species show a limited ability to detect regularity, most evidence suggests that birds attend primarily to absolute and not relative timing of patterns and to local features of stimuli. We conclude that, apart from some large parrot species, there is limited evidence for beat and regularity perception among birds and that the link to vocal learning is unclear. We next report experiments in which zebra finches and budgerigars (both vocal learners) were first trained to distinguish a regular from an irregular pattern of beats and then tested on various tempo transformations of these stimuli. The results showed that both species reduced the discrimination after tempo transformations. This suggests that, as was found in earlier studies, they attended mainly to local temporal features of the stimuli, and not to their overall regularity. However, some individuals of both species showed an additional sensitivity to the more global pattern if some local features were left unchanged. Altogether our study indicates both between and within species variation, in which birds attend to a mixture of local and global rhythmic features. van der Aa, J., Honing, H., & ten Cate, C. (2015). The perception of regularity in an isochronous stimulus in zebra finches (Taeniopygia guttata) and humans Behavioural Processes, 115, 37-45 DOI: 10.1016/j.beproc.2015.02.018 ten Cate, C., Spierings, M., Hubert, J., & Honing, H. (2016). Can Birds Perceive Rhythmic Patterns? A Review and Experiments on a Songbird and a Parrot Species Frontiers in Psychology, 7 DOI: 10.3389/fpsyg.2016.00730

Sunday, May 08, 2016

Can humans listen like songbirds do?

European Starling ©

Humans and songbirds share many interesting similarities with regard to their auditory processing capabilities. For example, we know that humans and European Starlings have similar frequency sensitivity, perceive the pitch of the missing fundamental, and parse multiple pure-tone sequences into separate auditory streams. At higher levels, the “musical” nature of birdsong has long been appreciated by humans, and some songbirds can readily learn to discriminate and imitate human melodic sequences (cf. Hoeschele et al., 2015).

Given these similarities, it is surprising to find a major difference in how humans and songbirds perceive sequences of tones. Humans readily recognize tone sequences that are shifted up or down in log frequency because the pattern of relative pitches is maintained (referred to as relative pitch). In contrast, songbirds appear to have a strong bias to rely on absolute pitch for the recognition of tone sequences (a pitch-shifted melody might well be perceived as an altogether different melody; Hoeschele et al., 2015).

Interestingly, a recent study by Bregman et al. (2016), contrasting pitch and spectral patterns, shows that birds perceive their song more like humans perceive speech (Shannon, 2016). More precisely, songbirds might attend more to the acoustic spectral shape than to the absolute pitch of the acoustic signal. Stimuli that preserve acoustic spectral shape, even in the absence of pitch, seem to allow for generalization of learned acoustic patterns. Hence it could well be that a sensitivity to spectral shape is what is shared between human and avian cognition of musical signals, while relative pitch is the preferred mode of listening for humans. And one could wonder: why is sound "super normally stimulated" in humans (see earlier entry), and can humans be made to change their listening mode in the direction of birds (or vice versa) when manipulating melody and spectral shape? Bregman, M., Patel, A., & Gentner, T. (2016). Songbirds use spectral shape, not pitch, for sound pattern recognition Proceedings of the National Academy of Sciences, 113 (6), 1666-1671 DOI: 10.1073/pnas.1515380113 Hoeschele, M., Merchant, H., Kikuchi, Y., Hattori, Y., & ten Cate, C. (2015). Searching for the origins of musicality across species Philosophical Transactions of the Royal Society B: Biological Sciences, 370 (1664), 20140094-20140094 DOI: 10.1098/rstb.2014.0094 Shannon, R. V. (2016). Is Birdsong More Like Speech or Music? Trends in Cognitive Sciences, 20 (4), 245-247 DOI: 10.1016/j.tics.2016.02.004

Friday, April 22, 2016

Interested in a PhD position at the University of Amsterdam?

The Institute for Logic, Language and Computation (ILLC) at the University of Amsterdam (UvA) currently has two PhD positions available at the Faculty of Science starting on 1 September 2016 (or as soon after that as possible). Applications are now invited from excellent candidates wishing to conduct research in an area within ILLC (i.e. mathematics, artificial intelligence, linguistics, philosophy, musicology and/or cognitive science) that fits naturally in the Faculty of Science. See website for more information.

N.B. The deadline for applications is 15 May 2016

Tuesday, February 23, 2016

Gaat muzikaliteit aan muziek én taal vooraf? [Dutch]

Foto: Iris Vette
Hoe het brein van onze verre voorouders eruitzag, is niet meer na te gaan. Toch is er via een omweg misschien iets te zeggen over het ontstaan van taal, en de rol die muziek daarbij speelde.

Veel taalkundigen geloven —vreemd genoeg— dat onze liefde voor muziek meelift op ons taalvermogen (zie bijvoorbeeld NRC van twee weken geleden en Steven Pinker's invloedrijke boek How the mind works). Maar zou het niet, en even waarschijnlijk, precies andersom kunnen zijn?

Voor een overzicht van de recente ontwikkelingen op het gebied van de neurowetenschappen van taal en muziek, zie bijv. Peretz et al. (2015), Norman-Haignere et al. (2015) en de video hieronder: een registratie van de lezing Voor de muziek uit die ik afgelopen winter gaf op het tweejaarlijkse congres Onze Taal in het Chassé Theater in Breda.

UPDATE: Een samenvatting van de tekst verscheen in het tijdschrift Onze Taal. De integrale tekst verscheen in het interdisciplinaire tijdschrift Blind.

ResearchBlogging.orgNorman-Haignere, S., Kanwisher, N., & McDermott, J. (2015). Distinct Cortical Pathways for Music and Speech Revealed by Hypothesis-Free Voxel Decomposition Neuron, 88 (6), 1281-1296 DOI: 10.1016/j.neuron.2015.11.035

ResearchBlogging.orgPeretz, I., Vuvan, D., Lagrois, M., & Armony, J. (2015). Neural overlap in processing music and speech Philosophical Transactions of the Royal Society B: Biological Sciences, 370 (1664), 20140090-20140090 DOI: 10.1098/rstb.2014.0090

Monday, February 22, 2016

De juiste toon: had Pythagoras gelijk? [Dutch]

In muziek zijn vele wiskundige en natuurkundige wetten te vinden. Liggen die patronen aan de basis van wat we mooi vinden? Hebben onze hersenen een voorkeur voor bepaalde patronen? En hoe zit het met andere culturen, die weer andere patronen waarderen?

Over al deze zaken werd er stevig gediscussieerd tijdens de BètaBreak van 18 november j.l. met Michiel Schuijer (Muziektheoreticus, lector aan Conservatorium van Amsterdam), Henkjan Honing (hoogleraar Muziekcognitie aan de UvA) en Jan van de Craats (hoogleraar Wiskunde aan de UvA). Enkele van de referneties die genoemd worden staan hieronder (Plomp & Levelt, 1965; Savage et al., 2015).

De benadering van muziek als een natuurkundig of wiskundig verschijnsel heeft als mogelijke valkuil om naast geluidsleer een soort getallenleer te worden. Alsof harmonische, mooie of ‘juiste’ muziek door de natuur bepaald of zelfs afgedwongen wordt. Er klinkt iets in terug van het, in steeds wisselende gedaantes terugkerende Oudgriekse idee van een ‘harmonie der sferen’, het idee dat de wiskundige structuur van muziek iets zou kunnen onthullen over de natuur zelf. Of omgekeerd: dat een elegante formule die de code van de muziek van vermaarde componisten (denk aan Bach) weet te kraken en de onderliggende getallenstructuur ervan blootlegt, ons kan laten zien hoe mooi, hoe ‘natuurlijk’ die muziek is. Maar al Pythagoras’ ideeën over consonantie in termen van heeltallige ratio’s ten spijt: een hedendaagse, zorgvuldig maar allesbehalve heeltallig gestemde piano wordt door opvallend weinig mensen als ‘vals’ ervaren. Het is de eeuwenoude tegenstelling tussen muziek opgevat als getal en muziek als empirisch feit (cf. Pythagoras versus Aristoxenus). Muziek huist niet zozeer in het geluid of in het getal, maar eerder in het hoofd van de luisteraar (Honing, 2012).

ResearchBlogging.orgHoning, H. (2012). Een vertelling. In S. van der Maas, C. Hulshof, & P. Oldenhave (Eds.), Liber Plurum Vocum voor Rokus de Groot (pp. 150-154). Amsterdam: Universiteit van Amsterdam (ISBN 978-90-818488-0-0)
ResearchBlogging.orgPlomp R, & Levelt WJ (1965). Tonal consonance and critical bandwidth. The Journal of the Acoustical Society of America, 38 (4), 548-60 PMID: 5831012
ResearchBlogging.orgSavage, P., Brown, S., Sakai, E., & Currie, T. (2015). Statistical universals reveal the structures and functions of human music Proceedings of the National Academy of Sciences, 112 (29), 8987-8992 DOI: 10.1073/pnas.1414495112

Sunday, February 21, 2016

Does musicality have a biological foundation?

Genes with functions that are relevant to music aptitude such as hearing, cognitive performance and neurodegenerative functions are marked by triangles (From Liu et al., 2016).
A few days ago a study was published by the team of Irma Järvelä (University of Helsinki) on the identification of genetic variants underlying musical ability. They based their new study (Liu et al., 2016) on an existing database of ca. 150 unrelated Finnish subjects that were tested for their musical ability using a collection of pitch and pattern perception tests. In addition, for all participants genomic DNA was available (based on a blood sample). The participants were divided into two groups (low vs high musical aptitude), with the lower scoring individuals functioning as the control group.

The study focused on regions that can be associated with positive selection (Sabeti et al., 2006). Using genomic and bioinformatic techniques, the researchers were able to identify those regions that contain sets of variations in the DNA and show which regions are likely under positive selection.

The regions that were identified contained genes that are involved in auditory perception (e.g. GPR98, USH2A), cognition and memory (e.g. GRIN2B, IL1A, IL1B, RAPGEF5), reward mechanisms (RGS9), and song perception and production of songbirds (e.g. FOXP1, RGS9, GPR98, GRIN2B).

There are, of course, some drawbacks in this study that is largely exploratory. While the study was able to identify positively selected regions, the actual genes involved and their function remains unclear. Musicality is, obviously, a complex trait that likely has many contributing genes, and developing a proper phenomics is still quite a challenge (cf. Gingras et al., 2015). Nevertheless, the study suggests that several genes – that can be argued to be essential for musical aptitude (or musicality at large) – could well be under positive selection. The result hence supports the idea that musicality has a biological foundation that is necessary for the development of musical culture.

ResearchBlogging.orgLiu, X., Kanduri, C., Oikkonen, J., Karma, K., Raijas, P., Ukkola-Vuoti, L., Teo, Y., & Järvelä, I. (2016). Detecting signatures of positive selection associated with musical aptitude in the human genome Scientific Reports, 6 DOI: 10.1038/srep21198

ResearchBlogging.orgSabeti, P. (2006). Positive Natural Selection in the Human Lineage Science, 312 (5780), 1614-1620 DOI: 10.1126/science.112430

ResearchBlogging.orgGingras, B., Honing, H., Peretz, I., Trainor, L., & Fisher, S. (2015). Defining the biological bases of individual differences in musicality Philosophical Transactions of the Royal Society B: Biological Sciences, 370 (1664), 20140092-20140092 DOI: 10.1098/rstb.2014.0092

Saturday, February 06, 2016

Do songbirds perceive melody different from humans?

European Starling (Sturnus vulgaris)
Last week a fascinating study appeared in PNAS on melody (re)cognition in sparrows (Sturnus vulgaris). It provides an alternative interpretation to the widespread believe that songbirds have a strong bias to rely on absolute pitch (AP) for the recognition of melodies (e.g. Hulse et al., 1992).

In a series of behavioral experiments, Bregman et al. (2016) find that the human percepts of both pitch and timbre are poor descriptions of the perceptual cues used for melody recognition by the five sparrows that participated in the study. The results suggest that auditory sequence recognition in sparrows might be largely dependent on the perception of acoustic spectral shape, and not just AP. Sounds that preserve this shape, even in the absence of pitch cues, seem to be perceived as equivalent. The finding suggests that songbirds (unlike humans, for whom pitch plays a dominant role in the perception of melodic sequences) rely on a perceptual representation that is a combination of pitch and timbre. It suggests that the perceptual separability of pitch and timbre might also in humans be largely based on experience. Hulse, S., Takeuchi, A., & Braaten, R. (1992). Perceptual Invariances in the Comparative Psychology of Music Music Perception: An Interdisciplinary Journal, 10 (2), 151-184 DOI: 10.2307/40285605 Bregman, M., Patel, A., & Gentner, T. (2016). Songbirds use spectral shape, not pitch, for sound pattern recognition Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.1515380113

Monday, February 01, 2016

Abnormalities in later cognitive stages of beat processing?

Mathieu in 2012 (Dutch Tv).
A few years ago I reported on the start of a series of experiments with Mathieu, a case of congenital beat deafness (Phillips-Silver et al., 2011; see here). The paper reporting on that work just came out:
"Beat deafness, a recently documented form of congenital amusia, provides a unique window into functional specialization of neural circuitry for the processing of musical stimuli: Beat-deaf individuals exhibit deficits that are specific to the detection of a regular beat in music and the ability to move along with a beat. Studies on the neural underpinnings of beat processing in the general population suggest that the auditory system is capable of pre-attentively generating a predictive model of upcoming sounds in a rhythmic pattern, subserved largely within auditory cortex and reflected in mismatch negativity (MMN) and P3 event-related potential (ERP) components. The current study examined these neural correlates of beat perception in two beat-deaf individuals, Mathieu and Marjorie, and a group of control participants under conditions in which auditory stimuli were either attended or ignored. Compared to control participants, Mathieu demonstrated reduced behavioral sensitivity to beat omissions in metrical patterns, and Marjorie showed a bias to identify irregular patterns as regular. ERP responses to beat omissions reveal an intact pre-attentive system for processing beat irregularities in cases of beat deafness, reflected in the MMN component, and provide partial support for abnormalities in later cognitive stages of beat processing, reflected in an unreliable P3b component exhibited by Mathieu – but not Marjorie – compared to control participants. P3 abnormalities observed in the current study resemble P3 abnormalities exhibited by individuals with pitch-based amusia, and are consistent with attention or auditory-motor coupling accounts of deficits in beat perception." (Mathias et al., 2016)

ResearchBlogging.orgPhillips-Silver, J., Toiviainen, P., Gosselin, N., Piché, O., Nozaradan, S., Palmer, C., & Peretz, I. (2011). Born to dance but beat deaf: A new form of congenital amusia Neuropsychologia DOI: 10.1016/j.neuropsychologia.2011.02.002 Mathias, B., Lidji, P., Honing, H., Palmer, C., & Peretz, I. (2016). Electrical brain responses to beat irregularities in two cases of beat deafness. Frontiers in Neuroscience. DOI: 10.3389/fnins.2016.00040.

Saturday, January 16, 2016

Interested in doing an MA in Historic Amsterdam?

Do you want to become a Master in Musicology at the University of Amsterdam? Find out more on the website of the University of Amsterdam. Deadline: 1 March 2016.