Action and perception: Neural indices of learning in infants

Early human development offers a unique perspective in investigating the potential cognitive and social implications of action and perception. Specifically, during infancy, action production and action perception undergo foundational developments. One essential component to examine developments in action processing is the analysis of others’ actions as meaningful and goal-directed. Little research, however, has examined the underlying neural systems that may be associated with emerging action and perception abilities, and infants’ learning of goal-directed actions. The current study examines the mu rhythm—a brain oscillation found in the electroencephalogram (EEG)—that has been associated with action and perception. Specifically, the present work investigates whether the mu signal is related to 9-month-olds’ learning of a novel goal-directed means-end task. The findings of this study demonstrate a relation between variations in mu rhythm activity and infants’ ability to learn a novel goal-directed means-end action task (compared to a visual pattern learning task used as a comparison task). Additionally, we examined the relations between standardized assessments of early motor competence, infants’ ability to learn a novel goal-directed task, and mu rhythm activity. We found that: 1a) mu rhythm activity during observation of a grasp uniquely predicted infants’ learning on the cane training task, 1b) mu rhythm activity during observation and execution of a grasp did not uniquely predict infants’ learning on the visual pattern learning task (comparison learning task), 2) infants’ motor competence did not predict infants’ learning on the cane training task, 3) mu rhythm activity during observation and execution was not related to infants’ measure of motor competence, and 4) mu rhythm activity did not predict infants’ learning on the cane task above and beyond infants’ motor competence. The results from this study demonstrate that mu rhythm activity is a sensitive measure to detect individual differences in infants’ action and perception abilities, specifically their learning of a novel goal-directed action.

Structural characterization of interaction of K11 and K63 mixed-linkage polyubiquitin chains with the tUIMs of epsin1

Ubiquitylation or covalent attachment of ubiquitin (Ub) to a variety of substrate proteins in cells is a versatile post-translational modification involved in the regulation of numerous cellular processes. The distinct messages that polyubiquitylation encodes are attributed to the multitude of conformations possible through attachment of ubiquitin monomers within a polyubiquitin chain via a specific lysine residue. Thus the hypothesis is that linkage defines polyubiquitin conformation which in turn determines specific recognition by cellular receptors. Ubiquitylation of membrane surface receptor proteins plays a very important role in regulating receptor-mediated endocytosis as well as endosomal sorting for lysosomal degradation. Epsin1 is an endocytic adaptor protein with three tandem UIMs (Ubiquitin Interacting Motifs) which are responsible for the highly specific interaction between epsin and ubiquitylated receptors. Epsin1 is also an oncogenic protein and its expression is upregulated in some types of cancer. Recently it has been shown that novel K11 and K63 mixed-linkage polyubiquitin chains serve as internalization signal for MHC I (Major Histocompatibility Complex I) molecule through their association with the tUIMs of epsin1. However the molecular mode of action and structural details of the interaction between polyubiquitin chains on receptors and tUIMs of epsin1 is yet to be determined. This information is crucial for the development of anticancer therapeutics targeting epsin1. The molecular basis for the linkage-specific recognition of K11 and K63 mixed-linkage polyubiquitin chains by the tandem UIMs of the endocytic adaptor protein epsin1 is investigated using a combination of NMR methods.

Augmented Dissent: The Affordances of ICTs for Citizen Protest (A Case Study of the Ukraine Euromaidan Protests of 2013-2014).

This dissertation research project uses the Euromaidan protests in Ukraine to inform and shape a theory of augmented dissent to help explain the complex ways in which protest participants guided by the political, social, and cultural contexts engage in dissent augmented by ICTs in a reality where both the physical and the digital are used in concert. The purpose of this research is to conceptualize the use and perception of ICTs in protest activity using the communicative affordances framework. Through a mixed-method research approach involving interviews with protest participants, as well as qualitative and thematic analysis of online content from social media pages of several key Euromaidan protest communities, the research project examines the role ICTs played in the information and media landscape during the Euromaidan protest. The findings of the online content analysis were used to inform the questions for the 59 semi-structured, open-ended interviews with Euromaidan protest participants in Ukraine and abroad. The research findings provide in-depth insights about how ICTs were used and perceived by protest participants, and their role as vehicles for information and civic media content. The study employs the theoretical framework of social media affordances to interpret the data gathered during the interviews and content analysis to better understand how digital media augmented citizens’ protest activity through affording them new possibilities for dissent, and how they made meaning of said protest activity as augmented by ICTs. The findings contribute towards shaping a theory of digitally augmented dissent that conceptualizes the complex relationship between citizens and ICTs during protest activity as an affordance-driven one, where online and offline tools and activity merge into a unified dissent space and extend or augment the possibilities for action in interesting, and sometimes unexpected ways. Such a conceptual model could inform broader theories about civic participation and digital activism in the post-Soviet world and beyond, as ICTs become an inseparable part of civic life.