Melbourne School of Psychological Sciences - Theses

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    Chromatic contrast sensitivity functions measured using optokinetic nystagmus and psychophysics
    Pellicci, Joel Allan ( 2020)
    Optokinetic nystagmus (OKN) is a sequence of involuntary eye movements comprising slow phases of tracking a moving stimulus followed by fast saccades to reset the eye position. Although previous studies have studied the relationship between human OKN and functional vision via measurement of the contrast-sensitivity function (CSF), it has not been investigated using colour-varying, red-green, equiluminant patterns. In human vision, spatiotemporal changes in luminance convey a stronger sense of motion than do equiluminant patterns; yet, motion can nevertheless be perceived without luminance cues. The present study used spatial-frequency, band-pass luminance and red-green equiluminant noise patterns to measure OKN, and thus characterise the chromatic input to the mechanisms that drive the optokinetic response. The CSFs of 21 observers with normal vision were recorded using OKN and perceptual report. The results of the study demonstrate that an equiluminant red green stimulus can evoke a robust OKN response. There was a high correlation between OKN and perceptual report, for both luminance and colour stimuli, an indication of a common neural mechanism for defining stimulus direction. In all stimulus conditions tested, OKN can deliver a valid alternate technique for measuring the CSF.
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    Intelligence analysis in multidisciplinary teams - affordances of the collaborative online SWARM platform for public service and education application
    Wright, Andrew James ( 2020)
    Intelligence analysts from Australian Commonwealth, State and Territory Government agencies and departments regularly work in teams with other roles, referred to in this research as multidisciplinary teams (MDTs). MDTs operate within a ‘framework’, which provides the central mechanism for team coordination and structure. However, there is little available research on intelligence MDT frameworks including challenges. To address this gap and explore potential MDT frameworks, this thesis examines intelligence MDTs and the Hunt Lab’s collaborative software prototype SWARM Platform as a framework to support the functions of intelligence MDTs. The Hunt Lab developed the Platform in 2017 to improve collaboration and quality of reasoning of intelligence analysts. We investigated whether the Platform can move beyond its origins to provide a framework to support the business and training functions of intelligence MDTs, including affordances for managers and educators. As a first step, we developed a maturity model, informed by the intelligence teamwork literature for the purposes of defining and evaluating the key indicators of intelligence MDTs. We detail the development of our maturity model that contains seven pillars against which MDT performance could be evaluated: Mission, Accountability, Agility, Efficiency, Communication, Collaboration and Output. This maturity model formed the central coding mechanism for this research to evaluate MDT performance. We conducted three studies to address our research questions focusing on current MDT workplace application and whether the Platform supports business and training MDT framework functions. Study 1 applied the maturity model to a case study of intelligence MDT performance in the Australian Government, where we identified Mission and Collaboration as a strength but Efficiency as a weakness of their MDT framework. In Studies 2 and 3, we evaluated the Platform as a potential framework to support the business and training functions of intelligence MDTs, first in a small-scale pilot within an Australian Government workplace and then on a larger scale in an analytical competition involving public and intelligence organisation teams. In these two studies, we found the Platform mostly supported key MDT pillars but also identified varying weaknesses across pillars of Accountability, Efficiency and Communication. Despite the Platform’s broad support for the MDT maturity pillars, this research identified technical and cultural issues that prevent adoption of the Platform as a business framework without further prioritised research. Instead, our research indicates the Platform has more immediate benefits in supporting training functions as a computer-supported collaborative learning (CSCL) tool, where research participants reported both cognitive and social learning outcomes in the same studies. This research developed insights relevant to MDT frameworks more broadly including scaffolding strategies to improve multiple maturity model pillars. These strategies include teamwork schema development; launch meetings; accountability practices; and data management. We also developed insights into engaging and researching government with intelligence functions that are an emergent but not unforeseen result from this research. These findings have implications for future collaboration between the tertiary research sector and government with intelligence functions.
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    The Impact of Comorbidities and Expectations on Functional Neurological Disorder Symptoms (FND)
    Huepe Artigas, Daniela Del Pilar ( 2020)
    Functional Neurological Disorder (FND) is a condition that encompasses a wide spectrum of neurological symptoms that do not have an organic explanation. It is not clear why some patients develop a specific neurological symptom. In our study we considered the most frequent FND sub-types: functional motor disorders (FMD) and non-epileptic seizures (NES). It has been purported that individuals with risk factors, create strong expectations about body sensations based on clinical experiences such as disease, injury or surgery. These expectations would impact the nervous system which in turn lead to functional symptoms. These symptoms are inconsistent in frequency and evolution across time, and they are vulnerable to suggestion. Thus, there are no objective measures that can account for the symptoms. This thesis aims to determine whether previous clinical factors affecting different parts of the body have a relationship with the development of functional motor disorder (FMD) and non-epileptic seizures (NES), and to carry out a preliminary study of a measure capable of identifying perceptual differences in patients with functional weakness, the most reported symptom. In the first study we analysed the medical records of 108 FND patients (52 FMD and 56 NES), and in the second study we applied the Size-Weight Illusion (SWI) to 11 FND patients with functional weakness and 15 healthy controls (HC). It was found that patients with motor symptoms (FMD) had significantly higher rates of clinical factors that affected their limbs prior to the symptom onset than NES. Moreover, contrary to predicted, patients with NES had a similar rate of events that affected their head than FMD. However, NES had a higher rate of clinical factors during their lifetime than FMD, such as dissociative symptoms, suicidal ideation, and being victim of bullying, which affect the mind, and from the patients’ perspective they can be considered as located in the head. In the second study, FND and HC experienced a similar size-weight illusion. The severity and laterality of the symptom did not impact on the strength of the illusion, nor the dominance of the affected side. However, we propose that it is likely to find an effect in FND with a larger sample size. Otherwise, if similar results were found in future studies, the SWI might be a test that provides an objective assessment to confirm FND has a normal perception of weight relative to size.