Interactive brains:How infant cognition interacts with the dynamic social world

Research taking a cognitive neuroscience approach has shed light on social cognition during infancy. These studies have provided invaluable knowledge about how infants process social information, but a number of concepts regarding infant social cognition are often discussed based on research utilising rigidly controlled experimental paradigms where the role of infants is typically passive as an observer of stimuli. Increasing evidence suggests differences between the social cognitive processes that occurs when we act as observers of others (a ‘third-person’ perspective) and the processes that emerge when we are actively engaging with other people in an interactional context (a ‘second-person’ perspective) (e.g., Redcay and Schilbach, 2019; Siposova & Carpenter, 2019). Accordingly, there has been a growing recognition that we need a ‘second-person’ perspective, as compared to conventional “third-person” approach. The aim of the current thesis is to explore the interplay between infant cognition and the social world surrounding them, by moving research settings to a more naturalistic and dynamic one where infants are positioned as part of interaction. Towards this goal, Study 1 (Chapter 2) reviewed the current progress of “second-person” neuroscience research to evaluate the validity and robustness of simultaneous dual brain scanning techniques, often referred to as hyperscanning. The review identified large heterogeneity in reported effect sizes between published studies, suggesting the need to improve comparability of research, such as establishing standardised methods or promoting open science practices including code and data sharing to achieve higher reproducibility. This thesis then turned to research using various techniques from a conventional screen-based paradigm to a more dynamic setting, with the aim of building a stable platform towards second-person cognitive neuroscience approaches that investigate infant cognition while the infant actively interacts with other people. Study 2 (Chapter 3) explored how infants encode information differently from two adults who give gaze cues to a target object with different levels of accuracy. Whilst the study utilised a conventional event-related potential paradigm using screen-based stimuli, this paradigm could be adapted to enable future studies to investigate how infants’ social cognitive ability to discriminate reliable and unreliable informants can inform their subsequent behaviour observed in a social interactional behavioural task. Study 3 (Chapter 4) moved towards the use of more dynamic video stimuli and explored the neural processing of unexpected events. The study identified challenges in using dynamic perceptual inputs as stimuli. Study 4 (Chapter 5) transitioned into more naturalistic social contexts and analysed infant cognition while 10-month-old infants were faced with an adult demonstrating novel object labels in a live interaction. The study not only showed the feasibility of second-person neuroscientific research with infant participants, but also advanced our knowledge about infant word learning a step further, and demonstrated the trajectory from the encoding of semantic word information to its consolidation as knowledge. Study 5 (Chapter 6) also utilised a naturalistic interactional setting where infants were able to actively engage in a social task with an experimenter in a live manner, and aimed to identify systematic differences in neural activity between 9-month-old infants who make perseverative errors originally reported by Piaget (1954) and those who do not. This study was, to our knowledge, the first of its kind to validate the feasibility of utilising neurophysiological measures in this traditional interactive behavioural paradigm, in such a way that it does not interfere with the standard procedure. This thesis produced a series of studies which jointly demonstrate the potential for conducting research in a more dynamic setting that investigates infant social cognition taking a ‘second-person’ cognitive neuroscience approach to advance our knowledge about the intricate interaction between infant cognition, behaviour and the environment. We conclude this thesis by addressing the challenges of such an approach, to which we also attempt to propose solutions, as well as discussing future directions for the field

Supporting navigation using different types of spatial information : an experimental human factors study

This thesis presents research which examines how the display of location-based information on a mobile device affects navigation. The research was informed by current literature and user research conducted with Nottinghamshire Fire and Rescue Services. Experimental results are explained in terms of Passini’s (1980) model of wayfinding. Design guidelines and a human-factors framework for mobile location-based services are also presented. Cognitive task analysis and semi-structured interviews were used to conduct a user requirement study with firefighters from Nottinghamshire Fire and Rescue Services. Following this study, an experimental programme was developed to test how different methods of presenting information and displaying different types of information affected navigation. Measurements included time taken to navigate a route, workload, perceived usability and perceived navigational ability. A small scale observational study examined user behaviour while navigating with GPS enabled information. Finally, a focus group was used to evaluate the results from the experimental work with Nottinghamshire Fire and Rescue Services. Qualitative studies suggest that firefighters could use mobile, location based information to enhance navigation in large incidents. This information should be easy to understand and act on, incurring the minimum of cognitive demand. To achieve these requirements, the type of information presented on a paper map should not simply be transferred directly to a mobile device but must be adapted. The type of information displayed must also take into account the environment to maximise navigation efficiency and minimise cognitive demand. In the inside environment, simplified information showing only main features such as staircases and route changes should be displayed. In the outside environment paths and a selection of large, permanent features such as buildings support navigation most effectively. Evaluation with the fire service indicates that firefighters concur with the results of the experimental program. Major areas of further research include collaborative designs involving multiple mobile services and further experimental work examining how the presentation of specific features affects navigation in the outside environment

Supporting navigation using different types of spatial information : an experimental human factors study

This thesis presents research which examines how the display of location-based information on a mobile device affects navigation. The research was informed by current literature and user research conducted with Nottinghamshire Fire and Rescue Services. Experimental results are explained in terms of Passini’s (1980) model of wayfinding. Design guidelines and a human-factors framework for mobile location-based services are also presented. Cognitive task analysis and semi-structured interviews were used to conduct a user requirement study with firefighters from Nottinghamshire Fire and Rescue Services. Following this study, an experimental programme was developed to test how different methods of presenting information and displaying different types of information affected navigation. Measurements included time taken to navigate a route, workload, perceived usability and perceived navigational ability. A small scale observational study examined user behaviour while navigating with GPS enabled information. Finally, a focus group was used to evaluate the results from the experimental work with Nottinghamshire Fire and Rescue Services. Qualitative studies suggest that firefighters could use mobile, location based information to enhance navigation in large incidents. This information should be easy to understand and act on, incurring the minimum of cognitive demand. To achieve these requirements, the type of information presented on a paper map should not simply be transferred directly to a mobile device but must be adapted. The type of information displayed must also take into account the environment to maximise navigation efficiency and minimise cognitive demand. In the inside environment, simplified information showing only main features such as staircases and route changes should be displayed. In the outside environment paths and a selection of large, permanent features such as buildings support navigation most effectively. Evaluation with the fire service indicates that firefighters concur with the results of the experimental program. Major areas of further research include collaborative designs involving multiple mobile services and further experimental work examining how the presentation of specific features affects navigation in the outside environment

Can neural activities during the traditional Piagetian AB search task explain infants’ perseverative search error? : Preliminary results

Since the infant perseverative error (AB error) was first reported by Piaget in 1954, these findings have been well replicated. Yet there is no general agreement on why the error occurs and what aspect of infants’ cognition AB error reflects. Since looking and reaching measures have yielded mixed evidence of infant ability, neurological measures indexing online cognitive processes may shed light on the mechanisms underlying the error, clarifying how different experimental manipulations may highlight different aspects of infants’ cognition involved in the error. In this pilot study, we monitored neural activities while infants engaged in the task in a live setting. We tested 50 9-month-old infants and the final sample consisted of the data from 36 infants. EEG data collected during a 5-second delay period between infants’ observing the toy being hidden and their being allowed to search were grouped into 4 conditions according to the phase (A- or B-trial) and their performance (accurate or inaccurate). The result indicated that theta-band oscillatory activities might perhaps predict infants’ search performance. However, due to the small number of data and large individual differences, none of the statistical comparisons found a significant difference across conditions. Nevertheless, a methodological procedure and analysis pipeline for future EEG research using a live AB task has been established. This pilot study has positioned us ready to untangle a complex cognitive process involved in a behavioural task such as this AB search task utilising a neurological measure

Genotoxic effect induced by hydrogen peroxide in human hepatoma cells using comet assay

Background: Hydrogen peroxide is a common reactive oxygen intermediate generated by variousforms of oxidative stress. Aims: The aim of this study was to investigate the DNA damage capacity ofH2O2 in HepG2 cells. Methods: Cells were treated with H2O2 at concentrations of 25 μM or 50 μM for5 min, 30 min, 40 min, 1 h or 24 h in parallel. The extent of DNA damage was assessed by the cometassay. Results: Compared to the control, DNA damage by 25 μM and 50 μM H2O2 increasedsignificantly with increasing incubation time up to 1 h, but it was not increased at 24 h. Conclusions:Our Findings confirm that H2O2 is a typical DNA damage inducing agent and thus is a good modelsystem to study the effects of oxidative stress. DNA damage in HepG2 cells increased significantlywith H2O2 concentration and time of incubation but later decreased likely due to DNA repairmechanisms and antioxidant enzyme

Biogas hydrogen as an indicator of digester instability in anaerobic sewage sludge digesters

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