Peter Langland-Hassan

Improvisation and the self-organization of multiple musical bodies

Understanding everyday behavior relies heavily upon understanding our ability to improvise, how we are able to continuously anticipate and adapt in order to coordinate with our environment and others. Here we consider the ability of musicians to improvise, where they must spontaneously coordinate their actions with co-performers in order to produce novel musical expressions. Investigations of this behavior have traditionally focused on describing the organization of cognitive structures. The focus, here, however, is on the ability of the time-evolving patterns of inter-musician movement coordination as revealed by the mathematical tools of complex dynamical systems to provide a new understanding of what potentiates the novelty of spontaneous musical action. We demonstrate this approach through the application of cross wavelet spectral analysis, which isolates the strength and patterning of the behavioral coordination that occurs between improvising musicians across a range of nested time-scales. Revealing the sophistication of the previously unexplored dynamics of movement coordination between improvising musicians is an important step toward understanding how creative musical expressions emerge from the spontaneous coordination of multiple musical bodies.

Inner speech deficits in people with aphasia

Despite the ubiquity of inner speech in our mental lives, methods for objectively assessing inner speech capacities remain underdeveloped. The most common means of assessing inner speech is to present participants with tasks requiring them to silently judge whether two words rhyme. We developed a version of this task to assess the inner speech of a population of patients with aphasia and corresponding language production deficits. Patients’ performance on the silent rhyming task was severely impaired relative to controls. Patients’ performance on this task did not, however, correlate with their performance on a variety of other standard tests of overt language and rhyming abilities. In particular, patients who were generally unimpaired in their abilities to overtly name objects during confrontation naming tasks, and who could reliably judge when two words spoken to them rhymed, were still severely impaired (relative to controls) at completing the silent rhyme task. A variety of explanations for these results are considered, as a means to critically reflecting on the relations among inner speech, outer speech, and silent rhyme judgments more generally.

Creating Time: Social Collaboration in Music Improvisation

Musical collaboration emerges from the complex interaction of environmental and informational constraints, including those of the instruments and the performance context. Music improvisation in particular is more like everyday interaction in that dynamics emerge spontaneously without a rehearsed score or script. We examined how the structure of the musical context affords and shapes interactions between improvising musicians. Six pairs of professional piano players improvised with two different backing tracks while we recorded both the music produced and the movements of their heads, left arms, and right arms. The backing tracks varied in rhythmic and harmonic information, from a chord progression to a continuous drone. Differences in movement coordination and playing behavior were evaluated using the mathematical tools of complex dynamical systems, with the aim of uncovering the multiscale dynamics that characterize musical collaboration. Collectively, the findings indicated that each backing track afforded the emergence of different patterns of coordination with respect to how the musicians played together, how they moved together, as well as their experience collaborating with each other. Additionally, listeners experiences of the music when rating audio recordings of the improvised performances were related to the way the musicians coordinated both their playing behavior and their bodily movements. Accordingly, the study revealed how complex dynamical systems methods (namely recurrence analysis) can capture the turn-taking dynamics that characterized both the social exchange of the music improvisation and the sounds of collaboration more generally. The study also demonstrated how musical improvisation provides a way of understanding how social interaction emerges from the structure of the behavioral task context.

Self-knowledge and imagination

How do we know when we have imagined something? How do we distinguish our imaginings from other kinds of mental states we might have? These questions present serious, if often overlooked, challenges for theories of introspection and self-knowledge. This paper looks specifically at the difficulties imagination creates for Neo-Expressivist, outward-looking, and inner sense theories of self-knowledge. A path forward is then charted, by considering the connection between the kinds of situations in which we can reliably say that another person is imagining, and those in which we can say the same about ourselves. This view is a variation on the outward-looking approach, and preserves much of the spirit of Neo-Expressivism.

Metacognitive deficits in categorization tasks in a population with impaired inner speech

This study examines the relation of language use to a persons ability to perform categorization tasks and to assess their own abilities in those categorization tasks. A silent rhyming task was used to confirm that a group of people with post-stroke aphasia (PWA) had corresponding covert language production (or inner speech) impairments. The performance of the PWA was then compared to that of age- and education-matched healthy controls on three kinds of categorization tasks and on metacognitive self-assessments of their performance on those tasks. The PWA showed no deficits in their ability to categorize objects for any of the three trial types (visual, thematic, and categorial). However, on the categorial trials, their metacognitive assessments of whether they had categorized correctly were less reliable than those of the control group. The categorial trials were distinguished from the others by the fact that the categorization could not be based on some immediately perceptible feature or on the objects being found together in a type of scenario or setting. This result offers preliminary evidence for a link between covert language use and a specific form of metacognition.

Metacognition without introspection

While Carruthers denies that humans have introspective access to cognitive attitudes such as belief, he allows introspective access to perceptual and quasi-perceptual mental states. Yet, despite his own reservations, the basic architecture he describes for third-person mindreading can accommodate first-person mindreading without need to posit a distinct “introspective” mode of access to any of ones own mental states.