Image by Paweł Czerwiński

Brain rhythms readily synchronize with auditory rhythms, like those in music and speech. Although brain–environment synchrony is associated with positive behavioral outcomes – we better understand and remember material when brain–environment synchrony is tighter – we’re missing an understanding of why one person might succeed in a listening situation while another might fail. The Research Group Neural and Environmental Rhythms takes a dynamical-systems approach to understanding brain–environment synchrony, conceptualizing and modeling brain rhythms as being generated by neural oscillators (and testing that assumption along the way). We combine individual-differences, experimental, and lifespan (later half for now) approaches, and make use of psychophysics, electrophysiology (M/EEG), and modeling to move towards a more wholistic, mechanistic understanding of brain–environment synchrony and its role in auditory perception.

Projects

Test–retest reliability of neural entrainment of the human auditory system

project leader: Yuranny Cabral-Calderin

Brain rhythms synchronize with the rhythms in sounds with a phase lag that is consistent across trials within an experiment, but not necessarily consistent across people.  Individual differences in this phase lag of neural entrainment have the potential to be interesting predictors of individual differences in listening performance (Henry & Obleser, 2012), and as such may serve as a target for noninvasive brain stimulation techniques. This project aims to establish the reliability of this phase lag across time, and to localize the neural sites of reliable entrainment in space, as first steps towards noninvasively targeting entrainment to sound rhythms.

Keywords – Entrainment, reliability, auditory perception, gap detection, EEG, oscillations, tACS, fMRI

 

Brain on Music

project leader: Kristin Weineck

This electroencephalography (EEG) study investigates the neural mechanisms underlying music and rhythm perception. We ask how tempo (also referred to as rate/speed) influences neural activity during the perception of music, with a particular emphasis on individual differences in the tempi at which we prefer to listen to music. This research project aims to answer the following questions: Do we like to listen to music at a specific rate and if so, can we find a neural correlate to support that preference? How does our recent “auditory history” (e.g., the song/tempo that we were just listening to) shape our auditory perception in the present moment? Are we able to find brain activity (the strength of neural entrainment to specific frequencies or the “fit” between neural activity and auditory stimulus) that has the ability to predict how we perceive music? To answer these questions we will acquire EEG data in healthy, young participants listening to music, but in the longer term, the study goals include the assessment of individual behavioral and neurophysiological differences during music perception and how these differences change with age.

Keywords – Neural entrainment, tempo, EEG, music perception, music features

 

Tap to the beat (the time is now)

project leader: Ece Kaya

This study aims to explore individual differences in our ability to synchronize our body movements with auditory rhythms (“rhythmic entrainment”). We work from the assumption that motor synchronization is accomplished by entrainment of an oscillatory mechanism (here, we stay agnostic to exactly what that oscillatory mechanism is), and we focus on two properties of this internal oscillator: preferred rate (sometimes referred to as preferred tempo) and flexibility. The experiment is a synchronization–continuation tapping paradigm with a twist: Over the course of 400 trials, participants tap to 400 different tempi, and the trial-to-trial differences in tempo are maximized so that participants’ ability to flexibly adjust is pushed to the limit. We hypothesize that 1) tapping performance will be better (lower variability, smaller asynchrony) when the sequence tempo matches an individual's preferred rate and, 2) individuals with more flexible oscillators will be better at adapting to changes in tempo. We take a model-based approach to examining the various individual and contextual factors that may be involved in rhythmic entrainment and performance.

 

Rhythm production

project leader: Olivia Wen

This study is designed to measure individual's internal preferred tempo (also referred to as preferred rate) – the tempo at which individuals prefer to produce, listen to, and perceive auditory stimuli. We designed a novel rhythm task, where individuals produce rhythms from a schematic, pictorial representation. No auditory stimuli are presented at any point during the experiment, so that there are no cues to the tempo (rate) at which the rhythm should be produced. Instead, we measure the spontaneous tempo/rate at which each participant naturally produces the rhythms. We examine a number of contributors to the quality and tempo of the rhythm productions, for example: meter (duple vs. triple), rhythmic complexity (measured using a model-based approach), amount of practice on the task, musical experience and skill.

 

Neural entrainment to rhythmically irregular sounds

project leader: Yuranny Cabral-Calderin, Vera Komeyer

Keywords – Entrainment, irregularity, flexibility, EEG, gap detection, auditory perception, oscillations

Here, we explore under what circumstances neural entrainment breaks down and how this differs between individuals, with the goal to better understand listening success in suboptimal environments. We measure EEG while participants detect gaps embedded in frequency modulated sounds, where the degree of regularity conveyed by the frequency modulation is parametrically varied. Thus, we challenge the brain's ability to entrain to rhythms with less and less rhythmicity. This project aims not only to assess individual differences in the degree to which entrainment breaks down with decreasing temporal regularity, but will reveal neural "compensatory" mechanisms that support listening when a "rhythmic mode" is unavailable.