Computational and Imaging Methods for Studying Neuronal Populations during Behavior

One of the central questions in neuroscience is how the nervous system generates and regulates behavior. To understand the neural code for any behavior, an ideal experiment would entail (i) quantitatively defining that behavior, (ii) recording neuronal activity in relevant brain regions to identify the underlying neuronal circuits and eventually (iii) manipulating them to test their function. Novel methods in neuroscience have greatly advanced our abilities to conduct such experiments but are still insufficient. In this thesis, I developed methods for these three goals. In Chapter 2, I describe an automatic behavior identification and classification method for the cnidarian Hydra vulgaris using machine learning. In Chapter 3, I describe a fast volumetric two-photon microscope with dual-color laser excitation that can image in 3D the activity of populations of neurons from visual cortex of awake mice. In Chapter 4, I present a machine learning method that identifies cortical ensembles and pattern completion neurons in mouse visual cortex, using two-photon calcium imaging data. These methods advance current technologies, providing opportunities for new discoveries

Minimally Invasive Expeditionary Surgical Care Using Human-Inspired Robots

This technical report serves as an updated collection of subject matter experts on surgical care using human-inspired robotics for human exploration. It is a summary of the Blue Sky Meeting, organized by the Florida Institute for Human and Machine Cognition (IHMC), Pensacola, Florida, and held on October 2-3, 2018. It contains an executive summary, the final report, all of the presentation materials, and an updated reference list

Word Superiority Effects in Dyslexics

Distorting the word superiority effect with intraword spacing was used to investigate the processing difference in single-word reading for dyslexics and controls. Perfetti’s Reading model suggests that dyslexics would have reduced processing capacity with intraword spacing. Results from a Covid-modified experimental protocol generally did not support the hypothesis. There was poor differentiation between groups in the word capacity coefficient. Response time by itself was also not informative. However, dyslexics had reduced accuracy in distractor identification across intraword spacings due to the lack of retention in phonological working memory or attention in central executive deficit (Alt, Fox, Levy, et al., 2022; Gray, Green, Alt, et al., 2017) as matching targets was not an issue, only confirmation of an update was problematic. In target identification, early responses and later responses were predictive of WIAT III Pseudoword (phonetic processing) and WAIS-IV Symbol Search (visuospatial matching task). These preliminary results motivate further research regarding word processing differences in dyslexic and controls

A framework for assistive communications technology in cross-cultural healthcare

Rural and remote Australian Aboriginal communities suffer seriously adverse life expectancy rates, lifestyle disease complications and hospital treatment needs due to type 2 diabetes. In great part this is due to communications barriers arising from the lack of equitable acculturation within patient-practitioner consultations. This research presents a framework foundation for a computerised patient-practitioner lingua franca. Behavioural and design science ontology development delivers an intercultural patient-practitioner type 2 diabetes assistive communications system, known as P-PAC

Methods and Apparatus for Autonomous Robotic Control

Sensory processing of visual, auditory, and other sensor information (e.g., visual imagery, LIDAR, RADAR) is conventionally based on "stovepiped," or isolated processing, with little interactions between modules. Biological systems, on the other hand, fuse multi-sensory information to identify nearby objects of interest more quickly, more efficiently, and with higher signal-to-noise ratios. Similarly, examples of the OpenSense technology disclosed herein use neurally inspired processing to identify and locate objects in a robot's environment. This enables the robot to navigate its environment more quickly and with lower computational and power requirements

Designing personalized video-based crossmedia informal learning environments beyond iTV

Tese de doutoramento, Informática (Engenharia Informática), Universidade de Lisboa, Faculdade de Ciências, 2014Video is a very rich medium, in cognitive and affective terms, to convey information and support learning and entertainment like no other medium, and TV is a privileged way to watch it. However, by being traditionally watched in a more experiential and passive cognitive mode, TV and video are limited in their capacity to fully support learning so important in the lifelong learning era where learning is taking place in a wide variety of contexts and locations that calls for flexible environments. TV and video are limited in their capacity to fully support learning but may induce viewers to engage in more reflective modes, that can be supported to some extent by their adequate design, in interactive contexts and augmented by other media and devices, in diverse situations. The inclusion of iTV that has been gaining increasing attention from researchers, and practitioners, in the last few years, as part of rich and flexible crossmedia environments brings new opportunities in this respect. This situation justifies our research main goal to efficiently and flexibly support users learning informal opportunities created in video-based crossmedia environments, taking into account the different cognitive modes, contexts of use and taking advantage of the diverse devices being used in order to have each device contributing with what it does best. In order to illustrate, explore and validate our research, the eiTV application was conceptualized, prototyped and evaluated. It is capable to create videobased crossmedia informal learning environments, created as additional information to the video being watched, initially via iTV. These environments are accessed from iTV, PC and mobile devices (the most commonly used in crossmedia scenarios), depending on the preferred or most adequate device in each context of use.Fundação para a Ciência e a Tecnologia (FCT, SFRH/PROTEC/67727/2010, projeto UTA-Est/MAI/0010/2009

Interplay between astrocytic and neuronal networks during virtual navigation in the mouse hippocampus

Encoding of spatial information in hippocapal place cells is believed to contribute to spatial cognition during navigation. Whether the processing of spatial information is exclusively limited to neuronal cells or it involves other cell types, e.g. glial cells, in the brain is currently unknown. In this thesis work, I developed an analysis pipeline to tackle this question using statistical methods and Information Theory approaches. I applied these analytical tools to two experimental data sets in which neuronal place cells in the hippocampus were imaged using two-photon microscopy, while selectively manipulating astrocytic calcium dynamics with pharmacogenetics during virtual navigation. Using custom analytical methods, we observed that pharmacogenetic perturbation of astrocytic calcium dynamics, through clozapine-n-oxyde (CNO) injection, induced a significant increase in neuronal place field and response profile width compared to control conditions. The distributions of neuronal place field and response profile center were also significantly different upon perturbation of astrocytic calcium dynamics compared to control conditions. Moreover, we found contrasting effect of astrocytic calcium dynamics perturbation on neuronal content of spatial information in the two data sets. In the first data set, we found that CNO injection resulted in a significant increase in the average information content in all neurons. In the second data set, we instead found that mutual information values were not significantly different upon CNO application compared to controls. Although the presented results are still preliminary and more experiments and analyses are needed, these findings suggest that astrocytic calcium dynamics may actively control the way hippocampal neuronal networks encode spatial information during virtual navigation. These data thus suggest a complex and tight interplay between neuronal and astrocytic networks during higher cognitive functions