Cross-linguistic differences in case marking shape neural power dynamics and gaze behavior during sentence planning

Languages differ in how they mark the dependencies between verbs and arguments, e.g., by case. An eye tracking and EEG picture description study examined the influence of case marking on the time course of sentence planning in Basque and Swiss German. While German assigns an unmarked (nominative) case to subjects, Basque specifically marks agent arguments through ergative case. Fixations to agents and event-related synchronization (ERS) in the theta and alpha frequency bands, as well as desynchronization (ERD) in the alpha and beta bands revealed multiple effects of case marking on the time course of early sentence planning. Speakers decided on case marking under planning early when preparing sentences with ergative-marked agents in Basque, whereas sentences with unmarked agents allowed delaying structural commitment across languages. These findings support hierarchically incremental accounts of sentence planning and highlight how cross-linguistic differences shape the neural dynamics underpinning language use.This work was funded by Swiss National Science Foundation Grant Nr. 100015_160011 (B.B. and M.M.), the NCCR Evolving Language, Swiss National Science Foundation Agreement Nr. #51NF40_180888 (B.B. and M. M.), and the PhD Program in Linguistics and the Graduate Research Campus of the University of Zurich (A.E.). DEB is supported by a grant from the Harvard Data Science Initiative and the Branco Weiss Foundation. I.B.-S. is supported by an Australian Research Council Future Fellowship (FT160100437). I.L. is supported by grants from the Spanish Ministry of Economy and Competitiveness (Grant No. FFI2015-64183-P) and the Basque Government (IT1169-19). The authors thank Anne-Lise Giraud for the suggestion to include beta-band analyses, Vitória Piai for advice on EEG data processing, Giuachin Kreiliger for statistical consultation, Andrina Balsofiore and Edurne Petrirena for help recording the lead-in fragments, Nathalie Rieser and Debora Beuret for help with data collection and processing, and the Phonogram Archives of the University of Zurich for technical support. The authors also thank two anonymous reviewers for their helpful comments on an earlier version of the manuscript

Actividad del sistema de neuronas espejo durante la percepción y acción de movimientos de dedos

Resumen: La comprensión de los mecanismos neuronales involucrados en la percepción y acción de movimientos puede contribuir a la formación de músicos y cirujanos. En ese marco, la presente investigación tuvo como objetivo determinar la actividad del sistema de neuronas espejo durante la observación y ejecución de movimientos de dedos. Para ello, se registró la actividad cerebral de seis participantes (tres hombres y tres mujeres) con edades entre 21 y 26 años con un equipo BIOPAC durante tres condiciones experimentales: observación, ejecución y control. La tarea consistió en observar o ejecutar el movimiento de tocar las puntas de los dedos con la punta del dedo pulgar secuencialmente a una frecuencia de 2Hz. Por otra parte, la condición de control consistió en observar una almohada en posición estática. Después de descartar artefactos, se calculó la desincronización relacionada a eventos (DRE) en cada condición experimental y en cuatro bandas de frecuencia. Pruebas de Wilcoxon mostraron que la condición ejecución (Mdn = -41.70) tuvo valores de DRE más pronunciados que la condición de control (Mdn = -8.6) (Z = - 3.58) (r=-.73). Asimismo, indicaron que no hubo diferencias entre la condición de observación (Mdn = -30.95) y las condiciones de ejecución (Z = 2.04) (r=.42) y control (Z = -2.22) (r=-.45). Los resultados aportan evidencia favorable pero no concluyente respecto al rol del sistema de neuronas espejo en la vinculación de la percepción y acción de movimientos de dedos. Mejoras metodológicas son necesarias para generalizar los hallazgos y evaluar sus potenciales aplicaciones en la educación.Abstract: Understanding the neural mechanisms involved in perception and action of movements can contribute to the training of musicians and surgeons. In this context, the present study was aimed to determine the activity of the mirror neuron system during observation and execution of sequential finger movements. To do this, the brain activity of six participants (three males and three females) was recorded with a BIOPAC MP100 in three experimental conditions: observation, execution and control. The experimental task was to observe or execute the movement of touching the fingertips with the tip of the thumb sequentially at a frequency of 2 Hz. Similarly, the control condition was to observe a pillow in a static position. After discarding artifacts, the event-related desynchronization (ERD) was computed in each of the three experimental conditions and in four frequency bands. Wilcoxon tests showed that the execution condition ERD values (Mdn = -41.70) were more pronounced than the control condition ones (Mdn = -8.6) (Z = -3.58) (r=-.73). They also indicated that the observation condition did not have different ERD values than the execution (Z = 2.04) (r=.42) and the control conditions (Z = -2.22) (r=-.45). These results provide supportive but not conclusive evidence regarding the role of the human mirror neuron system in linking perception and action of finger movements. Methodological improvements are required to generalize these findings and assess their potential applications in education.Tesi

Investigating attentional function and cognitive fluctuations in Lewy body dementia

PhD ThesisLewy body dementias (LBD), which include dementia with Lewy bodies (DLB) and Parkinson’s disease with dementia (PDD), are characterised by attentional dysfunction and fluctuating cognition. The underlying aetiology of these clinical features is poorly understood, yet such knowledge is essential for developing effective management strategies. The aim of this project was to determine the specific facets of attention affected in LBD patients, and to use high-density electroencephalography (EEG) to delineate the underlying pathophysiology and how this relates to cognitive fluctuations. Methods: Attentional network efficiency was investigated in LBD patients (n = 32), Alzheimer’s disease (AD) patients (n = 27), and age-matched healthy controls (n = 21) by using a modified version of the Attention Network Test (ANT). The ANT, a visual attention task, probes the efficiency of three anatomically defined attentional networks: alerting, orienting and executive conflict. Participants completed the ANT whilst undergoing EEG recordings (128 channels). In a subsample of the participants (22 DLB, 24 AD, 19 controls), time-frequency wavelet analyses were conducted to investigate event-related spectral perturbations (ERSP), between 4-90 Hz, in the 500 ms post-stimuli presentation. Attentional network ERSP was calculated by contrasting the oscillatory reactivity following relevant stimuli. Results: Overall mean reaction time was slower in the dementia groups (AD and LBD) relative to the controls, and the LBD group were slower than the AD group. Behaviourally, there were no group differences regarding the orienting effect. However, both dementia groups exhibited reduced executive conflict processing efficiency, and a lack of an alerting effect. Electrophysiologically, the DLB group exhibited a profound lack of post-stimulus oscillatory reactivity below 30 Hz, irrespective of stimulus condition. For the alerting network, the DLB group exhibited attenuated reactivity in the lower frequencies (< 30 Hz); in the theta range (4-7 Hz) the controls and AD group showed global synchronisation (across all regions), peaking at approximately 300 ms, which was absent in the DLB group. Lack of DLB theta synchronisation between 200-450 ms over the right parietal cortex was associated with a ii higher total score on the Clinical Assessment of Fluctuation scale. Orienting and executive conflict network reactivity was comparable across all groups; primarily intermittent synchronisation, of reduced power relative to the alerting network, diffuse across the time and frequency domains in all regions. Conclusions: Attenuated global oscillatory reactivity in the DLB group specific to the alerting network (the network associated with the ability to maintain an alert state) is indicative of this fractionated aspect of attention being differentially affected in the DLB patients relative to the AD and control groups. Lack of theta reactivity in the parietal regions may contribute to the underlying pathophysiology of cognitive fluctuations in DLB.Alzheimer’s Research U

On the effects of transcranial alternating stimulation (tACS) on neuronal dynamics and cognition.

A few minutes at a busy square in London allow one to appreciate the wide array of actions that humans are capable of expressing— walking, reading a book, tapping touch screen of smartphone, eating, shaking hands and crossing the street. Response inhibition is an essential mechanism of action control and is one of the most studied processes. For example, crossing the street when a fast motorcycle is approaching might necessitate inhibition of stepping forward to avoid being hurt. This ability to quickly suppress a response in a dynamic environment has traditionally been associated with conscious control. Crucially, recent experimental evidence has challenged the view that inhibitory control is restricted to conditions where stimuli are accessible to conscious awareness. Such an unconscious and automatic activation of the motor response system does not necessarily require stimuli to be consciously perceived and is deemed essential to act in a constantly changing environment. This has been interpreted as a basic motor process allowing preparatory mechanisms to automatically suppress an activated movement without the need of conscious cognitive processes. Thus, while there may be differences between automatic and voluntary processes, they might not have entirely distinct neural representations. Indeed, automatic control appears to rely on the corticobasal ganglia network that has been associated with voluntary control. Contemporary research has shown that an up-regulation of neural beta oscillations in the cortico-basal ganglia dynamics can be functionally relevant for inhibition of movement. Consequently, beta oscillations have been proposed as an essential mechanism that allows the motor network to communicate in a dynamic and flexible manner. Present research has demonstrated that it is possible to interact with the neuronal activity by non invasive brain stimulation (NIBS) techniques such as transcranial Direct Current Stimulation (tDCS), transcranial Alternating Current Stimulation (tACS). Specifically, tACS allows delivery of alternating current at different frequencies and it has been used to manipulate ongoing brain oscillations in a controllable way. This concept is still in the very early stages of research, and much needs to be done in order to fully grasp the underlying mechanisms. Building upon these discoveries, the research presented in this thesis aimed to demonstrate a causal role of beta frequency oscillations on unconscious and automatic inhibition adopting tACS over the primary motor cortex and supplementary motor area. Furthermore combining tACS with TMS and EEG allowed me to characterise the underlying basic mechanisms of its action on corticospinal excitability and neuronal dynamics. Overall, this work contributes to our understanding of the human motor system while offering new insights into the combined approach of tACS and EEG in the characterization of a causal role of neuronal oscillatory dynamics on behaviour

Understanding Conceptual Design Activities: Extended Axiomatic Theory of Design Modeling and Physiological Experimentation

Conceptual design is an early and critical phase of a design process. Decisions made in this stage can affect seventy five percent of the manufacturing costs. Therefore, one of the important factors to successful production is to have methods and tools that enable designers to work more effectively during the phase of conceptual design. To build such methods and tools, knowledge of design activities such as nature of the design process and factors affecting design activities is indispensable. The present thesis is a continuing effort to build a science of design which aims to discover knowledge of design activities through formal scientific process. The contribution of the current thesis includes the extended Axiomatic Theory of Design Modelling and methodologies to study design cognition physiologically. In particular, two postulates were added to the Axiomatic Theory of Design Modelling to support its explanatory power which was demonstrated through the interpretation of the impact of sketching on design performance and the occurrence of design fixation. An integrated experimental environment was developed to collect and analyze physiological signals during design processes. From this environment, several experiments recording physiological signals were conducted and findings of electroencephalography, heart rate variability, and skin conductance were reported

An EEGLAB plugin to analyze individual EEG alpha rhythms using the "channel reactivity-based method

A recent paper [1] proposed a new technique, termed the channel reactivity-based method (CRB), for characterizing EEG alpha rhythms using individual (IAFs) and channel (CAFs) alpha frequencies. These frequencies were obtained by identifying the frequencies at which the power of the alpha rhythms decreases. In the present study, we present a graphical interactive toolbox that can be plugged into the popular open source environment EEGLAB, making it easy to use CRB. In particular, we illustrate the major functionalities of the software and discuss the advantages of this toolbox for common EEG investigations. The CRB analysis plugin, along with extended documentation and the sample dataset utilized in this study, is freely available on the web at http://bio.dei.unipd.it/crb