Signalling plasticity and energy saving in a tropical bushcricket

Males of the tropical bushcricket Mecopoda elongata synchronize their acoustic advertisement signals (chirps) in interactions with other males. However, synchrony is not perfect and distinct leader and follower roles are often maintained. In entrainment experiments in which conspecific signals were presented at various rates, chirps displayed as follower showed notable signal plasticity. Follower chirps were shortened by reducing the number and duration of syllables, especially those of low and medium amplitude. The degree of shortening depended on the time delay between leader and follower signals and the sound level of the entraining stimulus. The same signal plasticity was evident in male duets, with the effect that the last syllables of highest amplitude overlapped more strongly. Respiratory measurements showed that solo singing males producing higher chirp rates suffered from higher metabolic costs compared to males singing at lower rates. In contrast, respiratory rate was rather constant during a synchronous entrainment to a conspecific signal repeated at various rates. This allowed males to maintain a steady duty cycle, associated with a constant metabolic rate. Results are discussed with respect to the preference for leader signals in females and the possible benefits males may gain by overlapping their follower signals in a chorus

Timing of antisynchronous calling: A case study in a harbor seal pup (Phoca vitulina)

Alternative mathematical models predict differences in how animals adjust the timing of their calls. Differences can be measured as the effect of the timing of a conspecific call on the rate and period of calling of a focal animal, and the lag between the two. Here, I test these alternative hypotheses by tapping into harbor seals’ (Phoca vitulina) mechanisms for spontaneous timing. Both socioecology and vocal behavior of harbor seals make them an interesting model species to study call rhythm and timing. Here, a wild-born seal pup was tested in controlled laboratory conditions. Based on previous recordings of her vocalizations and those of others, I designed playback experiments adapted to that specific animal. The call onsets of the animal were measured as a function of tempo, rhythmic regularity, and spectral properties of the playbacks. The pup adapted the timing of her calls in response to conspecifics’ calls. Rather than responding at a fixed time delay, the pup adjusted her calls’ onset to occur at a fraction of the playback tempo, showing a relative-phase antisynchrony. Experimental results were confirmed via computational modeling. This case study lends preliminary support to a classic mathematical model of animal behavior—Hamilton’s selfish herd—in the acoustic domain

THE ROLE OF MELATONIN IN BIOLOGICAL RHYTHMS OF SONGBIRDS

In vertebrates, melatonin is a hormone that is produced and secreted at night and inhibited by light. This unique “darkness-only” expression profile makes it an intellectually appealing candidate for a means of transmitting temporal information to an individual, both time of day and time of year. In passerine birds, “time of day” information is certainly transmitted via melatonin secretion. The primary producer of systemic melatonin in this family of birds is the pineal gland, and surgical removal of it causes a bird to become arrhythmic in constant conditions. I find that as pinealectomized house sparrows (Passer domesticus) become behaviorally arrhythmic in extended constant darkness the molecular clock in their peripheral tissues largely continues to cycle absent its hypothesized synchronizing cues from the pineal gland. This suggests that the peripheral tissues are either autonomous or that there is a possible secondary circadian oscillator that synchronizes these tissues, such as the avian suprachiasmatic nucleus. In passerine birds, “time of year” information is not transmitted via melatonin secretion to the primary gonads, unlike the case in seasonally breeding mammals. The duration of melatonin, longer in the winter and shorter in the spring as the photoperiod changes with the seasons, does affect secondary sexual characteristics, such as the vocal behavior of birds and the size of the associated nuclei in the brain. I find that long durations of melatonin are sufficient in preventing the photoperiodic expansion of vocal state in male house sparrows. This vocal state change in males consists of the development of a dawn and dusk chorus, as well as a switch from a vocal subtype associated with the wintertime birds flocking together to one of mate attraction and territory defense. This dynamic was independent of the size of the gonads, which were consistent those of photostimulated males. I also investigate this vocal state change in outdoor captive sparrows. This vocal state change is also present in female house sparrows, although unlike in male birds, the presence of absence of the pineal gland does not affect the timing of their vocalizations. Further, I investigate the ability for rhythmic presentations of vocalizations to influence the circadian clock, in zebra finches, Taeniopygia guttata. Aural cues have been shown to act as a weak external cue for entraining a passerine bird’s circadian clock. I presented various permutations of zebra finch vocalization: a single song played repeatedly, the same song played reversed, random tones, and live monitoring of a breeding colony entrained to a light-dark cycle. The live monitoring was the strongest aural cue, and more generally it appears that novelty and context enhance the effect of audio cues on the circadian clock. These experiments in sum suggest a role of melatonin in gating the seasonal expression of vocalization behavior in house sparrows. In male birds, a component of the seasonal dynamic is the development of a multimodal rhythm to when during the day the birds vocalize as the days lengthen consistent with spring, suggesting that the circadian clock may be involved with this diel variability. Additionally, this vocal behavior can also feedback onto the circadian clock. The pineal gland and its primary hormone melatonin function, in part, to regulate complex behavioral rhythms in passerine birds

Navigating Musical Periodicities: Modes of Perception and Types of Temporal Knowledge

This dissertation explores multi-modal, symbolic, and embodied strategies for navigating musical periodicity, or “meter.” In the first half, I argue that these resources and techniques are often marginalized or sidelined in music theory and psychology on the basis of definition or context, regardless of usefulness. In the second half, I explore how expanded notions of metric experience can enrich musical analysis. I then relate them to existing approaches in music pedagogy. Music theory and music psychology commonly assume experience to be perceptual, music to be a sound object, and perception of music to mean listening. In addition, observable actions of a metaphorical “body” (and, similarly, performers’ perspectives) are often subordinate to internal processes of a metaphorical “mind” (and listeners’ experiences). These general preferences, priorities, and contextual norms have culminated in a model of “attentional entrainment” for meter perception, emerging through work by Mari Riess Jones, Robert Gjerdingen, and Justin London, and drawing upon laboratory experiments in which listeners interact with a novel sound stimulus. I hold that this starting point reflects a desire to focus upon essential and universal aspects of experience, at the expense of other useful resources and strategies (e.g. extensive practice with a particular piece, abstract ideas of what will occur, symbolic cues) Opening discussion of musical periodicity without these restrictions acknowledges experiences beyond attending, beyond listening, and perhaps beyond perceiving. I construct two categories for various resources and strategies: those which involve dynamic symbolic encoding (such as conducting patterns and tala gestures) and those which utilize static theoretical information (such as score-based knowledge and calculation of abstract relationships). My primary means of revealing and exploring these additional resources involves instances of “metric multi-tasking,” in which musicians keep track of multiple non-nested periodicities occurring simultaneously. One of the reasons these situations work so well at revealing additional resources is that attentional entrainment offers no explanation for how one might be able to do such a thing (only that attention is insufficient for the task). I do not make these moves in an attempt to significantly alter the theory of attentional entrainment. Rather, I frame that model as but one mode of temporal perception among many. I also leave room for types of temporal knowledge which may not be perceptual at all, but are nonetheless useful in situations involving musical periodicity. Pedagogical systems already make use of dynamic symbols and theoretical knowledge to help with temporally difficult tasks, and generally not virtuosic feats of metric multi-tasking. With these ideas in mind, I return to more straightforward “mono-metric” contexts and reconsider what to do with the concepts of “meter” and “perception.

The Experiences of an Individual with Parkinson\u27s Engaging in a Relationship-based, Improvisational Music Therapy Group

This study explored the experiences of an individual with Parkinson’s engaging in a relationshipbased, improvisational music therapy group. The researcher utilized the methodology of naturalistic inquiry. An archived video recording of a group music therapy session held through a videoconferencing platform was observed. Music experiences and verbal dialogue were transcribed and put into notation software, and subsequently analyzed through inductive analysis. Two main themes were found: (a) Musical Interrelatedness and (b) Relationship Between Music and Words, with two subthemes under the former; Diane’s Musical Relationship with the Therapist and Diane’s Musical Relationship with the Group; and three under the latter; Words Enhancing Diane’s Musical Experience, Music Supporting Diane’s Verbal Responses, and Significance Of The Voice. Results illustrated the participant’s experience of a relationshipbased improvisational music therapy group as something supportive, creative, and potentially beneficial for their overall well-being

Tony Williams' drumset ideology to 1969: Synergistic emergence from an adaptive modeling of feel, technique and creativity as an archetype for cultivating originality in jazz drumset performance studies

I identify Tony Williams’ formative drumset ideology as being emergent from his adaptive modeling of the feel, technique and creativity identified in the drumming of Art Blakey, Max Roach and Philly Joe Jones respectively and present the results of extensive textual and musicological research on Williams’ formative practices between 1945 and 1969 as an archetype for cultivating originality in jazz drumset performance studies. I examine patterns of creative thought in the New York jazz community as they developed from the relative heteronomy of modernist bebop improvisation to the postmodernist aesthetic of jazz-rock fusion resulting in the emergence of collective autonomy in musical interaction and improvisation. My research reveals Willams’ possession of autotelic personality and utilisation of learning techniques associated with heutagogy. Also identified is the prevalence of entrainment in the social and musical interactions of the New York jazz community and I interpret these qualities through the lens of the theory of complex adaptive systems as a model for learning in jazz drumset performance studies. I analyse Williams’ ensemble and solo drumming in comparison to that of Blakey, Roach and Jones in addition to Roy Haynes by using an analytic schema designed specifically for identification of contrasting qualities in the voicing of rhythm and expression as revealed in the grouping and ordering of limbs in drumset performance. I present a complete stylistic overview of Williams’ recorded output until 1969 including swing, avant garde, ballad, straight eighth-note and sixteenth-note oriented styles as well as complex temporal events such as polymetric superimposition, rubato, polytempo, superimposed metric modulation, metric modulation and tempo fluctuation

The Idiosyncrasy of Involuntary Musical Imagery Repetition (IMIR) Experiences: The Role of Tempo and Lyrics

Involuntary musical imagery repetition (IMIR), colloquially known as “earworms,” is a form of musical imagery that arises involuntarily and repeatedly in the mind. A growing number of studies, based on retrospective reports, suggest that IMIR experiences are associated with certain musical features, such as fast tempo and the presence of lyrics, and with individual differences in music training and engagement. However, research to date has not directly assessed the effect of such musical features on IMIR and findings about individual differences in music training and engagement are mixed. Using a cross-sectional design (Study 1, n = 263), we examined IMIR content in terms of tempo (fast, slow) and presence of lyrics (instrumental, vocal), and IMIR characteristics (frequency, duration of episode and section) in relation to 1) the musical content (tempo and lyrics) individuals most commonly expose themselves to (music-listening habits), and 2) music training and engagement. We also used an experimental design (Study 2, n = 80) to test the effects of tempo (fast or slow) and the presence of lyrics (instrumental or vocal) on IMIR retrieval and duration. Results from Study 1 showed that the content of music that individuals are typically exposed to with regard to tempo and lyrics predicted and resembled their IMIR content, and that music engagement, but not music training, predicted IMIR frequency. Music training was, however, shown to predict the duration of IMIR episodes. In the experiment (Study 2), tempo did not predict IMIR retrieval, but the presence of lyrics influenced IMIR duration. Taken together, our findings suggest that IMIR is an idiosyncratic experience primed by the music-listening habits and music engagement of the individual

Virtual Choir: To Sing Together, Individually

The pandemic has forced choir practitioners and enthusiasts to shift from in-person rehearsal and performance to online and virtual choir performance. The virtual choir is seen as an alternative to choir activity during the pandemic. However, it also generates another concern related to its inclination to reduce the role of the conductor, singers, and social interaction in achieving musical targets and enhance the so-called social skills, empathy. The study employs two conductors in an in-depth interview to understand the condition and dynamics of online rehearsal and virtual choir performance. The exploration of the data emphasized three important themes: (1) the role of virtual choir to choir continuity, (2) the impact of virtual choir technology in reducing individuals’ role, and (3) the absence of in-person social interaction in empathy enhancement. Paduan Suara Virtual: Bernyanyi bersama, seorang diri Abstrak Pandemi memaksa praktisi dan penggemar paduan suara untuk beralih dari latihan dan penampilan live menjadi skema latihan online dan pertunjukan virtual. Paduan suara virtual dipandang sebagai alternatif untuk tetap menjalankan aktivitas paduan suara di kala pandemi. Namun, paduan suara virtual juga memunculkan keprihatikan dan perhatian khusus terkait kecenderungan untuk mereduksi peran konduktor, penyanyi, dan interaksi sosial dalam mencapai target musikal dan juga peningkatan keterampilan sosial, salah satunya empati. Penelitian ini berupa wawancara terfokus pada dua konduktor paduan suara yang bertujuan untuk menggali pemahaman terkait kondisi dan dinamika latihan daring dan pertunjukan paduan suara virtual. Hasil ekspolasi data dan analisis menunjukkan tiga tema penting yakni (1) peran paduan suara virtual untuk keberlanjutan aktivitas paduan suara, (2) dampak teknologi yang digunakan dalam paduan suara virtual terhadap reduksi peran humanis, dan (3) ketiadaan interaksi interpersonal secara langsung dan dampaknya terhadap peningkatan empati