Automatic Tonic Identification in Indian Art Music: Approaches and Evaluation

The tonic is a fundamental concept in Indian art music. It is the base pitch, which an artist chooses in order to construct the melodies during a rg(a) rendition, and all accompanying instruments are tuned using the tonic pitch. Consequently, tonic identification is a fundamental task for most computational analyses of Indian art music, such as intonation analysis, melodic motif analysis and rg recognition. In this paper we review existing approaches for tonic identification in Indian art music and evaluate them on six diverse datasets for a thorough comparison and analysis. We study the performance of each method in different contexts such as the presence/absence of additional metadata, the quality of audio data, the duration of audio data, music tradition (Hindustani/Carnatic) and the gender of the singer (male/female). We show that the approaches that combine multi-pitch analysis with machine learning provide the best performance in most cases (90% identification accuracy on average), and are robust across the aforementioned contexts compared to the approaches based on expert knowledge. In addition, we also show that the performance of the latter can be improved when additional metadata is available to further constrain the problem. Finally, we present a detailed error analysis of each method, providing further insights into the advantages and limitations of the methods.

Tonic current through GABAA receptors and hyperpolarization-activated cyclic nucleotide-gated channels modulate resonance properties of rat subicular pyramidal neurons

The subiculum, considered to be the output structure of the hippocampus, modulates information flow from the hippocampus to various cortical and sub-cortical areas such as the nucleus accumbens, lateral septal region, thalamus, nucleus gelatinosus, medial nucleus and mammillary nuclei. Tonic inhibitory current plays an important role in neuronal physiology and pathophysiology by modulating the electrophysiological properties of neurons. While the alterations of various electrical properties due to tonic inhibition have been studied in neurons from different regions, its influence on intrinsic subthreshold resonance in pyramidal excitatory neurons expressing hyperpolarization-activated cyclic nucleotide-gated (HCN) channels is not known. Using pharmacological agents, we show the involvement of alpha 5 beta gamma GABA(A) receptors in the picrotoxin-sensitive tonic current in subicular pyramidal neurons. We further investigated the contribution of tonic conductance in regulating subthreshold electrophysiological properties using current clamp and dynamic clamp experiments. We demonstrate that tonic GABAergic inhibition can actively modulate subthreshold properties, including resonance due to HCN channels, which can potentially alter the response dynamics of subicular pyramidal neurons in an oscillating neuronal network.

Glycine uptake regulates hippocampal network activity via glycine receptor-mediated tonic inhibition

Functional glycine receptors (GlyRs) are enriched in the hippocampus, but their role in hippocampal function remains unclear. Since the concentration of ambient glycine is determined by the presence of powerful glycine transporter (GlyT), we blocked the r

Differential efficiency of the endocytic machinery in tonic and phasic synapses

Efficient synaptic vesicle membrane recycling is one of the key factors required to sustain neurotransmission. We investigated potential differences in the compensatory endocytic machineries in two glutamatergic synapses with phasic and tonic patterns of activity in the lamprey spinal cord. Post-embedding immunocytochemistry demonstrated that proteins involved in synaptic vesicle recycling, including dynamin, intersectin, and synapsin, occur at higher levels (labeling per vesicle) in tonic dorsal column synapses than in phasic reticulospinal synapses. Synaptic vesicle protein 2 occurred at similar levels in the two types of synapse. After challenging the synapses with high potassium stimulation for 30 min the vesicle pool in the tonic synapse was maintained at a normal level, while that in the phasic synapse was partly depleted along with expansion of the plasma membrane and accumulation of clathrin-coated intermediates at the periactive zone. Thus, our results indicate that an increased efficiency of the endocytic machinery in a synapse may be one of the factors underlying the ability to sustain neurotransmission at high rates.

Carbon monoxide inhibition of Cav3.2 T-type Ca2+ channels reveals tonic modulation by thioredoxin

T-type Ca2+ channels play diverse roles in tissues such as sensory neurons, vascular smooth muscle, and cancers, where increased expression of the cytoprotective enzyme, heme oxygenase-1 (HO-1) is often found. Here, we report regulation of T-type Ca2+ channels by carbon monoxide (CO) a HO-1 by-product. CO (applied as CORM-2) caused a concentration-dependent, poorly reversible inhibition of all T-type channel isoforms (Cav3.1-3.3, IC50 ∼3 μM) expressed in HEK293 cells, and native T-type channels in NG108-15 cells and primary rat sensory neurons. No recognized CO-sensitive signaling pathway could account for the CO inhibition of Cav3.2. Instead, CO sensitivity was mediated by an extracellular redox-sensitive site, which was also highly sensitive to thioredoxin (Trx). Trx depletion (using auranofin, 2-5 μM) reduced Cav3.2 currents and their CO sensitivity by >50% but increased sensitivity to dithiothreitol ∼3-fold. By contrast, Cav3.1 and Cav3.3 channels, and their sensitivity to CO, were unaffected in identical experiments. Our data propose a novel signaling pathway in which Trx acts as a tonic, endogenous regulator of Cav3.2 channels, while HO-1-derived CO disrupts this regulation, causing channel inhibition. CO modulation of T-type channels has widespread implications for diverse physiological and pathophysiological mechanisms, such as excitability, contractility, and proliferation

A case for a revival of tonic sol-fa in the twenty-first century

The Tonic Sol-fa method of teaching singing was developed in England by John Curwen over a period of forty years from the 1840s until the 1870s. Although originally an aid to reading staff notation, the J 872 Standard Course saw staff notation dispensed with altogether in favour of its own notational system. By the end of the century it had spread from Britain to Australia, New Zealand, South Africa, Canada, the United States, India, China, Japan and the Pacific Islands. However, largely due to its notational isolation, Tonic Sol-fa declined markedly during the early twentieth century. Except for the incorporation of certain aspects into the Kodaly method, it has largely disappeared from contemporary music teaching practice. Surprisingly, however, Tonic Sol-fa in its nineteenth century form is presently "alive and well" in certain developing countries in Africa, Asia and the Pacific. This paper will present an analysis of Tonic Sol-fa and evaluate its characteristics in terms of contemporary pedagogical and notational theory. The paper will then report on the current use of Tonic Sol-fa in developing countries and it will be argued that, in certain of these countries, this nineteenth century teaching method and notational system has not only survived but has indeed flourished. It will be argued that, in at least one case, Tonic Sol-fa has been "indiginised" so that it has not only become an integral part of the musical culture but also has become part of the social fabric of the country. The case will be put for a revival of Tonic Sol-fa in developing countries where, for social, economic and educational reasons, an alternative model to that utilised in more highly developed countries may be more successful/ in promoting school and community choral music.

Tonic sol-fa in South Africa : a case study of endogenous musical practice

Tonic Sol-fa was introduced to South Africa during the mid nineteenth century initially by Christian missionaries and later by professional educators to schools, teacher training institutions and local communities. Despite Tonic Sol-fa being the principal means of formal pedagogy and the most commonly-accepted notational medium through which South African communities have developed and sustained what is unquestionably a vibrant choral music tradition, there has been some fairly forthright condemnation of the overall effects of European music - particularly tonal-functional harmony - on indigenous culture. Agawu (2003) and Nzewi (1999), for example, have identified what they describe as the adverse effects of European music on African culture.

This paper counters these criticisms in one respect. It argues that, as one of the most prominent manifestations of European musical culture in sub-Saharan Africa, Tonic Sol-fa represents what Ntuli (2001) identifies as endogenous knowledge - knowledge acquired from non-indigenous sources that has been assimilated and integrated with indigenous knowledge to become the collective heritage of a people. This contention is supported by four short case studies of indigenous South African composers - two past and two contemporary musicians - who have utilised Tonic Sol-fa in their choral music writing and teaching, albeit in differing ways. The paper aims to counter the general criticism that European music has been injurious to indigenous African culture; rather it argues that in reality this manifestation of European music represents an exemplar of endogenous knowledge.

Missionaries, music and method - dissemination of tonic sol-fa in Asia-Pacific countries during the nineteenth century

The Tonic Sol-fa method of teaching choral singing and its system of music notation was developed in England by John Curwen and propagated throughout the British Isles as a means of both enhancing Christian worship and achieving social reform. Tonic Sol-fa may be identified as an entirely foreign musical practice introduced to indigenous people in many British colonies and in other overseas countries during the nineteenth century as an instrument of Christian evangelism as well as of European cultural imposition. Nevertheless, indigenous communities were introduced to other aspects of European musical culture including a choral repertoire consisting of four-part hymnody and masterworks by Handel, Bach, Mozart, etc which sometimes resulted in the emergence of a school of indigenous composers writing in Tonic Sol-fa notation and using the tonal harmonic style. The result has been that in several countries-such as South Africa and Fiji for example-Tonic Sol-fa has been so fully assimilated into the ethnic culture that it has been "indigenized" and may now be said to represent a significant exogenous aspect of the musical culture in these countries.

Tonic Sol-fa was most commonly introduced to countries in the Asia-Pacific Region -as in Africa - by Christian missionaries who sought to exploit the attraction of hymns, particularly when sung in four-part harmony, as a means of evangelizing indigenous people who frequently regarded this aspect of missionary activity as a form of "magic". In particular, the Tonic Sol-fa method and notation gained a significant foothold in what were referred to as the South Sea Islands--especially in Fiji where today, the Fijian Hymn Book (1985 edition) is notated exclusively in Tonic Sol-fa. The vast majority of the Fijians are literate in Tonic Sol-fa notation and congregational singing in four parts is the norm in Fijian churches.

This paper will draw on data from nineteenth century journal sources, particularly The Tonic Sol-fa Reporter (1853-1888) and The Musical Herald (1889-1920), and will document the introduction and dissemination of Tonic Sol-fa in several Asia-Pacific countries where, unlike Australia and New Zealand, the indigenous population has maintained its own cultural and demographic predominance. Countries to be considered will include India, China (including Hong Kong), and Pacific Island nations. There will also be a consideration of the contemporary usage and applications of Tonic Sol-fa in the region, with specific reference to Fiji. It will be argued that countries where Tonic Sol-fa notation has become the norm should resist any external pressure to transfer to the standard staff notation merely for the sake of conformity. In the case of Fiji, almost universal music literacy has been achieved through Tonic Sol-fa and this should be recognized as an enviable social and cultural asset.

Tonic Sol-fa in contemporary choral music practice : a South African case study

The Tonic Sol-fa method of teaching choral singing was propagated throughout Britain during the nineteenth century with the dual objectives of enhancing Christian worship and achieving social reform. It was then imported to South Africa where it was introduced to indigenous people principally through Christian missionary activity and government schools. Although entirely of foreign origin, Tonic Sol-fa was so fully assimilated into African culture that it became effectively 'indigenised'. Due to its widespread use, it became the mainstay of community choral singing and may now be said to represent a significant exogenous aspect of present-day South African musical identity. However, there is little documentation regarding the type and extent of its use in contemporary choral music practice.

This paper will report on the use of Tonic Sol-fa in representative present-day choral music settings. Interview data collected from choir directors, trainers and teachers in Cape Town indicate that there is far from unanimous agreement on several aspects - in particular, the future of Tonic Sol-fa as a pedagogy and notational system. Improving educational opportunities for indigenous South Africans to undertake professional training in music are now threatening the traditional dominance of Tonic Sol-fa in indigenous culture. Nevertheless this research represents a useful case study of the continuing relevance of Tonic Sol-fa to an indigenous population who have 'made it their own' and developed a vibrant choral tradition which continues to both enrich and sustain their lives.