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    The multimodality of creaminess perception : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Manawatū Campus, Palmerston North, New Zealand. EMBARGOED until 21 August 2026.
    (Massey University, 2024-02-28) Fisher, Emily Claire
    Creaminess is a complex sensory sensation that drives consumer acceptability of milk. To date, creaminess research has focused on instrumental and compositional measures overlooking the critical consumer perspective. This research took a consumer-led approach to unlock new insights into the underlying sensory attributes driving consumer creaminess perception using perceptual modelling. Robust sensory data, from a trained panel, was combined with consumer approaches for accurate modelling. Initially, attributes and modalities perceived to drive milk creaminess were identified through discussion with consumers representative of two key dairy markets, China and New Zealand (NZ). Subsequently, a milk sample set (n=32) was developed, and an expert panel trained to profile the samples based on attributes identified by consumers. A novel methodological investigation, on the impact of panel training with Polarised Sensory Positioning (PSP) of the sample set, was also explored. Focusing on NZ consumers, participants (n=117) evaluated creaminess and liking perception of the milk samples. Critically, regression modelling was employed to identify key attributes driving creaminess perception based on expert panel data. Several novel findings were discovered. Drivers of creaminess differed to some degree between NZ and Chinese consumers indicating cultural differences across markets. Trained panel sensory data revealed multicollinearity between attributes measured to describe the sample set. Modelling approaches were able to identify key attributes required to predict creaminess. New findings that training has little impact on PSP outcomes was also ascertained. Pertinently combining four attributes, across different modalities, in an Elastic net regression model (‘yellow’, ‘watery’ flavour, ‘in-mouth thickness’ and ‘astringency’) successfully predicted creaminess (R2=0.9514), however these attributes were highly correlated with others retained in a PLS model. Each model had its relative merits. Of further note, consumer creaminess response was highly variable and cluster analysis revealed two different consumer segments with perception impacted by sensitivity to certain attributes: ‘green tinge’, ‘cardboard’, ‘salty’, ‘cooked’, ‘fat separation’, ‘grassy’, ‘buttery’, ‘melting’, ‘cream’ aroma, ‘smoothness’, and ‘astringent’. This research revealed new understanding concerning perceptual attributes contributing to consumer creaminess perception and provided clearer targets for the dairy industry to ensure milk creaminess levels align to consumer expectations and related commercial gain.
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    Development and validation of a field deployable test for the diagnosis of high-priority infectious animal diseases in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Manawatu, Palmerston North, New Zealand
    (Massey University, 2024-03-15) Bueno, Rudolfo
    In the event of infectious disease incursions, rapid and accurate diagnosis is essential for ensuring appropriate and prompt control measures are put in place to minimise further transmission. Foot and mouth disease (FMD) is one example of an exotic disease that could severely affect New Zealand’s livestock industries if introduced to this country. Pen-side testing can help by providing a rapid confirmation of a provisional diagnosis without the delays and risks associated with sending samples to a diagnostic laboratory. The aim of the work presented in this thesis was to develop and validate a field deployable diagnostic test system for prompt and accurate detection of FMD virus (FMDV). In addition, the test can be used to simultaneously detect two other viruses that would be expected to be on the differential diagnosis list: bovine viral diarrhoea type 1 (BVDV-1) and type 2 (BVDV-2). Chapter 1 comprises a brief literature review of FMDV infections in susceptible species, followed by a review of the current and emerging trends in field deployable diagnostics as applicable to animal diseases. In Chapter 2, a multi-criteria scoring and ranking model for identifying the best test platform for development of the deployable field test is presented. The general flow of the method consisted of defining the requirements for the ideal test platform, identifying, and shortlisting potential candidate systems, describing the criteria for evaluation, and scoring the candidate platforms against the criteria by a panel of recruited experts. This participatory and collective opinion provided a basis for selecting T-COR 8™ (Tetracore®) as the best overall fit-for-purpose. In Chapter 3, several easy techniques for processing clinical samples compatible with the selected test platform were examined. These protocols were applied to test panels comprising serial dilutions of BVDV-1 or equine rhinitis A virus (ERAV) in serum or oral swab samples. The latter was used as a proxy for FMDV. The protocols were compared to a reference extraction method based on the observed detection limit, as judged by quantification cycle (Cq) values generated in virus-specific reverse transcription quantitative polymerase chain reaction (RT-qPCR) assays. The complexity of sample manipulation and time required were also considered. Dilution of the sample with phosphate-buffered saline (PBS), with or without a pre-heating step, was chosen as the most suitable method for integration in the pen-side PCR testing. Development of the field assay’s controls is described in Chapter 4. These included a synthetic positive control transcript (R3+) that could be safely used with assays aimed at the detection of several pathogens associated with development of vesicular disease in cattle. The universal control transcript also incorporated an exogenous internal control (IC) target, which was designed to be used with a phage based (Qβ) internal control (IC) system. Optimization of a Qβ IC assay for use in the pen-side multiplex RT-qPCR (mRT-qPCR) is also included in this Chapter. In Chapter 5, development, and optimisation of mRT-qPCR for the differential detection of FMDV, BVDV-1 and BVDV-2, including detection of a Qβ as exogenous IC, is presented. The optimised mRT-qPCR showed linearity over five 10-fold dilutions of R3+ transcript, good efficiency, and low intra-and inter-assay variability. The mRT-qPCR was highly specific for the detection of representative FMDV serotypes and was also able to simultaneously detect BVDV-1 and BVDV-2 isolates. The assay did not react with other viruses that can produce vesicular lesions, nor did it react with unrelated bovine pathogens endemic in New Zealand. Multiplexing the four primer- and probe sets did not affect the performance and analytical sensitivity of the assay for the detection of individual components when compared to the respective singleplex assays. The diagnostic performance of the optimised mRT-qPCR for detecting FMDV, BVDV-1 and BVDV-2 is presented in Chapters 6 and 7. Diagnostic specificity was evaluated using sera and oral swabs from New Zealand cattle. Diagnostic sensitivity for FMDV detection was assessed using mock oral swabs from outbreak samples in two endemic countries (Lao PDR and Myanmar). The robustness of the field PCR was evaluated at three field locations with varied environmental conditions (New Zealand, Lao PDR, and Myanmar). Overall, the diagnostic specificity (DSp) of the field mRT-qPCR for three target viruses (FMDV, BVDV-1 and BVDV-2) was close to 100%, which was similar to the performance of respective reference PCRs. Although the diagnostic sensitivity (DSe) of the FMDV component was comparable to that obtained with the reference method, care must be taken in interpreting the result since FMD positive samples used for evaluation of the sensitivity of the mRT-qPCR were not sourced from New Zealand cattle. The mRT-qPCR also had high DSe for detecting BVDV-1 infected cattle when the BVDV RNA levels expected to be present in clinical samples from either persistently infected (PI) or transiently infected animals were considered. Pre-heating of samples increased the sensitivity of the BVDV-1 component of the assay. Further validation using additional FMDV-positive and negative clinical specimens should be attempted in the future. Overall, the work presented in this thesis resulted in the development of a simple, extraction-free pen-side PCR test that can be deployed around New Zealand for rapid and reliable detection of FMDV in the event of a suspected incursion. Future work to enhance its use would involve exploration of other methods of preparing samples so that the test can be utilised in screening sub-clinical FMDV infections during post-outbreak surveillance.
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    Assessment of positive emotion in horses : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Manawatū, New Zealand
    (Massey University, 2022) Stratton, Rachael Bridget
    Objective, non-invasive indicators of the subjective experience of positive emotion are required to support assessment and improvement of animal welfare. Emotion is unique to the individual and indicators of emotion are indirect. The aim of this thesis was to ascertain if body and facial behaviours and physiological parameters reflected the emotional experiences of horses. Following review of the theoretical and experimental literature, three experiments were conducted, and an alternative emotional arousal-valence framework was proposed. Based on the preferences of individual horses, the relative arousal level and emotional valence induced by four stimuli (wither grooming, motionless person, intermittent spray, and being left alone) were ordered. Behavioural and physiological parameters were then measured during exposure to each stimuli. The indicators of contrasting affective experiences in horses were found to be heart rate, heart rate variability, eye temperature, and behaviours involving legs, neck, tail, ears, eyes, eyebrows, mouth, chin, and nares. Several behaviours differed across all three arousal levels or valence levels. Positive emotional valence was indicated by a decreased rate of neck very low, left ear forward, left or right ear back, blink, angled eyebrow, nares flared, nares neutral, and/or an increased rate of chin wobble, small eye aperture, or oral investigation behaviours. Higher arousal was indicated by an increased rate of neck very high, tail swishing, or higher odds of contracted lips, and/or a decreased rate of right ear forward or to the side behaviours. Reduction from 16 to six parameters may be possible. The findings may be used to aid interpretation of horse emotional experience and in the assessment and improvement of horse welfare. The research approach and framework described in this research may be suitable for future research in horses and other species.
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    Security analyses for detecting deserialisation vulnerabilities : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Computer Science at Massey University, Palmerston North, New Zealand
    (Massey University, 2021) Rasheed, Shawn
    An important task in software security is to identify potential vulnerabilities. Attackers exploit security vulnerabilities in systems to obtain confidential information, to breach system integrity, and to make systems unavailable to legitimate users. In recent years, particularly 2012, there has been a rise in reported Java vulnerabilities. One type of vulnerability involves (de)serialisation, a commonly used feature to store objects or data structures to an external format and restore them. In 2015, a deserialisation vulnerability was reported involving Apache Commons Collections, a popular Java library, which affected numerous Java applications. Another major deserialisation-related vulnerability that affected 55\% of Android devices was reported in 2015. Both of these vulnerabilities allowed arbitrary code execution on vulnerable systems by malicious users, a serious risk, and this came as a call for the Java community to issue patches to fix serialisation related vulnerabilities in both the Java Development Kit and libraries. Despite attention to coding guidelines and defensive strategies, deserialisation remains a risky feature and a potential weakness in object-oriented applications. In fact, deserialisation related vulnerabilities (both denial-of-service and remote code execution) continue to be reported for Java applications. Further, deserialisation is a case of parsing where external data is parsed from their external representation to a program's internal data structures and hence, potentially similar vulnerabilities can be present in parsers for file formats and serialisation languages. The problem is, given a software package, to detect either injection or denial-of-service vulnerabilities and propose strategies to prevent attacks that exploit them. The research reported in this thesis casts detecting deserialisation related vulnerabilities as a program analysis task. The goal is to automatically discover this class of vulnerabilities using program analysis techniques, and to experimentally evaluate the efficiency and effectiveness of the proposed methods on real-world software. We use multiple techniques to detect reachability to sensitive methods and taint analysis to detect if untrusted user-input can result in security violations. Challenges in using program analysis for detecting deserialisation vulnerabilities include addressing soundness issues in analysing dynamic features in Java (e.g., native code). Another hurdle is that available techniques mostly target the analysis of applications rather than library code. In this thesis, we develop techniques to address soundness issues related to analysing Java code that uses serialisation, and we adapt dynamic techniques such as fuzzing to address precision issues in the results of our analysis. We also use the results from our analysis to study libraries in other languages, and check if they are vulnerable to deserialisation-type attacks. We then provide a discussion on mitigation measures for engineers to protect their software against such vulnerabilities. In our experiments, we show that we can find unreported vulnerabilities in Java code; and how these vulnerabilities are also present in widely-used serialisers for popular languages such as JavaScript, PHP and Rust. In our study, we discovered previously unknown denial-of-service security bugs in applications/libraries that parse external data formats such as YAML, PDF and SVG.
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    Generating mock skeletons for lightweight Web service testing : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Computer Science at Massey University, Manawatū New Zealand
    (Massey University, 2021) Randunu Pathirannehelage, Thilini Bhagya
    Modern application development allows applications to be composed using lightweight HTTP services. Testing such an application requires the availability of services that the application makes requests to. However, continued access to dependent services during testing may be restrained, making adequate testing a significant and non-trivial engineering challenge. The concept of Service Virtualisation is gaining popularity for testing such applications in isolation. It is a practise to simulate the behaviour of dependent services by synthesising responses using semantic models inferred from recorded traffic. Replacing services with their respective mocks is, therefore, useful to address their absence and move on application testing. In reality, however, it is unlikely that fully automated service virtualisation solutions can produce highly accurate proxies. Therefore, we recommend using service virtualisation to infer some attributes of HTTP service responses. We further acknowledge that engineers often want to fine-tune this. This requires algorithms to produce readily interpretable and customisable results. We assume that if service virtualisation is based on simple logical rules, engineers would have the potential to understand and customise rules. In this regard, Symbolic Machine Learning approaches can be investigated because of the high provenance of their results. Accordingly, this thesis examines the appropriateness of symbolic machine learning algorithms to automatically synthesise HTTP services' mock skeletons from network traffic recordings. We consider four commonly used symbolic techniques: the C4.5 decision tree algorithm, the RIPPER and PART rule learners, and the OCEL description logic learning algorithm. The experiments are performed employing network traffic datasets extracted from a few different successful, large-scale HTTP services. The experimental design further focuses on the generation of reproducible results. The chosen algorithms demonstrate the suitability of training highly accurate and human-readable semantic models for predicting the key aspects of HTTP service responses, such as the status and response headers. Having human-readable logics would make interpretation of the response properties simpler. These mock skeletons can then be easily customised to create mocks that can generate service responses suitable for testing.
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    Automated 3D weaving continuous natural fibre and optimising harakeke fibre characterisation : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Mechatronics at Massey University, Albany, New Zealand
    (Massey University, 2019) Lin, Junyi
    This research investigated the design and implementation of a continuous natural fibre filament winding robot for modern artistic and structural architectural design. The idea of a new architectural construction technique based on Arduino integration was inspired by the underwater nesting structure of water spiders. It consists of the motion component, a 3-axis sliding table with limit switches, the construction of the machine, the programming and testing of the resulting microcomputer software through to a robot manufacturing process. This was based on Arduino’s new integrated development environment. In addition, the intelligent programming mode forms the preconceived pattern through winding, producing a model with unique architectural quality, and at the same time, making a structure with superior material efficiency. In terms of hardware design, the first conceptual model focused on using an open-source integrated development environment (IDE) that could be easily configured. Arduino hardware was the primary microcontroller of choice for simplicity and ease of hardware integration and software development. Stepper motor drivers are used to control the three stepper motors to accurately move the fibre feeding mechanism on the sliding table into position. The path of the sliding table is controlled by the controller, and the machine can make forward, backward, wire feed and other movements according to the programmed commands. The developed system automatically weaves and feeds natural fibre into the desired structure. The resulting lightweight natural fibre material forms a model with unique architectural quality. The results show that the model is of great value and significance, and it can be used to make the required structure with the desired natural fibre. Additionally, to establish the feasibility of future work focusing on harakeke fibre development in design and construction, the tensile strength of native New Zealand flax fibre (harakeke fibre) was evaluated with a view for use in these load bearing and architectural design applications. Single filament fibres were selected in batches and tensile tested. The longitudinal strength of specimens was established, and the mechanical properties of the fibres were summarised. Comparison of these attributes with existing data was used to determine if the harakeke fibre can be applied usefully in the construction industry. This research is based on the novel concept of architectural design in the construction industry using 3D weaving with natural fibres, in particular harakeke fibres. To achieve this, several related topics are under investigation, such as the need to design an improved feeding system (including hardware and software control), impregnation of fibre and resin (epoxy and polyester) to make preimpregnated (prepreg) fibre/resin filament, adaptive controlled programme and hardware for the required architecture and structure, and properties testing and characterisation. This project is one of the first attempts to develop an automated robot arm system combined with new material, in this case harakeke fibre, and has made a valuable contribution to this field of research.
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    A validation of the workplace dignity scale : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Manawatū, New Zealand
    (Massey University, 2019) Scott-Campbell, Casey
    Workplace Dignity has long been the subject of scholarly enquiry, although until recently the body of research has been dominated by ethnographic work. Recently, Thomas and Lucas (2019) developed the first quantitative, direct measure of perceptions of workplace dignity: the Workplace Dignity Scale (WDS). Given the importance of understanding dignity in the workplace, this study sought to replicate the initial scale validation study conducted by Thomas and Lucas, so as to confirm the reliability and validity of the scale prior to its future applied and scholarly use. Moreover, the current study contributes to the ongoing methodological reform of psychology towards a transparent and rigorous science by preregistering the method and analysis script prior to collecting data. A large sample of workers (N = 853) from the United States were recruited through Prolific Academic and completed an online questionnaire that included the WDS, as well as theoretically related scales (e.g., workplace incivility). Confirmatory factor analyses indicated that the model specified by Thomas and Lucas had reasonable global fit and estimates of reliability (ωt) indicated that the two main factors of the scale, Dignity and Indignity, had high internal consistency. Nomological analyses revealed that the Dignity factor of the WDS was significantly correlated in the expected directions with theoretically related variables. Furthermore, the Dignity and Indignity factors of the WDS were found to highly correlate with one another, posing questions as to whether the two factors are qualitatively different phenomena as was argued by Thomas and Lucas. It is concluded that the WDS is a promising tool for measuring workplace dignity although refinement of the proposed measurement model may be necessary.
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    The space around us : utilizing the hand-blink reflex to model defensive peripersonal space, and exploring interactions with state anxiety : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Manawatū campus, New Zealand
    (Massey University, 2019) Colville, Mark Allan
    Personal Space is a complex field, including boundaries used in social interactions, navigation and defence. The Defensive Peripersonal Space (DPPS) is a close proximity personal space used for defence, thought to be located within reaching distance. The DPPS is measured in individuals by the Hand-Blink Reflex (HBR), a blink reflex triggered by electrical stimulation of the median nerve at the wrist. By triggering the HBR while varying the hands distance from the face, an individual’s DPPS can be approximated. The field of DPPS and HBR research is however new and the HBR method is highly complex. This study replicated a HBR testing method, finding support for the presence of the DPPS, while finding the method extremely delicate, and in need of refinement and clarification. It is anticipated that this study will add help refine the HBR testing method, and be a useful addition to the field.
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    Catalytic steam reformer tubes non-destructive inspection technology investigation and advancement : a dissertation presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Engineering at Massey University, Manawatu Campus, New Zealand
    (Massey University, 2018) Fukuoka, Morio
    Catalytic Steam reforming is a chemical synthesis process used in the production of hydrogen by mixing hydrocarbon with steam in the presence of a metal-based catalyst. This is achieved in a steam reformer plant where the mixture of gases is elevated to high pressure and temperature through a continuous process for efficient mass production of syngas to meet the global hydrogen demand. One of the challenges in operating a steam reformer plant is monitoring and maintaining the tubular reactors (Reformer tube). Under the severe service conditions the tubes a subjected to various degradation mechanism which ultimately determine the service life. With the tubes accounting to over 20% of the capital cost of a reformer plant, it is of great significance to maximise the service life of each tubes, which has been the motivation to the advancement in metallurgy and NDT technology around reformer tubes from the introduction of Catalytic Steam reforming in the early 20th century. Under the influence of long-term exposure of mechanical stressing and elevated temperature, reformer tube is subjected to a material degrading phenomenon call creep deformation. In 1952, F.R. Larson and J. Miller devised the Larson-Miller Parameter which predicts the lifetime of a material based on service temperature and stress-rupture time and for decades this method was used design and managed reformer tubes on a time-based strategy of 10,000 service hour. However, case studies have time and time shown premature rupture of reformer tube causing unexpected downtime resulting in significant loss in production and asset. Hence engineers and researchers have worked on a more direct method of assessing the remaining service life of reformer tubes. Inline pipe inspection is a hot area of research in robotics and automation. Eddy current, laser profilometry, ultrasonic and infrared thermography is the four technology that is currently dominating the Reformer industry, of which laser profilometry assessment being the only method capable of early stage creep detection. While other fields of pipe inspection have advanced and industrially applied over past decades, it is the author's opinion that NDT technology for reformer tube is outdated with areas of innovation. The aim of this research is to investigate an alternative solution to overcome the challenges and limited faced in modern systems and contribute to the advancement of NDT of Catalytic Steam reformer tubes. Presented in this dissertation is a new framework for an autonomous Reformer Tube inspection system, which incorporates a number of innovative elements for improved creep damage assessment. The program for this work is comprised of three studies. In the first study, the challenges around process profilometry dataset is demonstrated, the limitation in the available methods is discussed, and the impacts in regards to detection creep deformation is identified. Based on the finding, a three-stage creep detection algorithm (CDA) is derived, offering a dynamic solution to distinguish two modes of isotropic and anisotropic creep deformation. The system is experimentally assessed using a set of profilometry measurements collected from retire reformer tube. In the second study, a novel method for tracking a motion of an object moving inside a reformer tube is devised. Literature study showed that conventional profilometry system suffers from measurement uncertainty cause from an uncontrolled rotation of measurement instruction during an inspection. Because location information gives valuable insight as to the performance of the plant, the long-range optic solution is conceptualised, based on polarising filters and Malus Law, to overcome these limitations. In this research, a proof of concept experiment is conducted to evaluate and justify the conceptual method through the development of a working prototype. This novel technique is named Optical Position Tracking (OPT) system. Presented in the final study is an autonomous reformer tube inspection system developed on the basis of the results and finding in the first portion of the research. The contribution of this research is demonstrated with a working prototype justifying the practicality of CDA and the OPT system. The design incorporates wireless communication, modular design, and modern semiconductor sensing technology. In conclusion, this research met the first milestone for an ongoing research to progress the NTD industry.
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    The effect of eye movements on traumatic memories and the susceptibility to misinformation : a partial replication : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Manawatū, New Zealand
    (Massey University, 2018) Sievwright, Olivia
    The issue of whether certain techniques used in psychotherapy might increase false memories is a major source of contention between cognitive and practising psychologists. Recently, a study by Houben, Otgaar, Merckelbach, and Roelofs (2018) found that bilateral eye movements used in Eye Movement Desensitisation and Reprocessing (EMDR) therapy increase susceptibility to misleading information. EMDR is a popular treatment for posttraumatic stress disorder and is primarily thought to reduce the vividness and emotional intensity of traumatic memories. Individuals who undergo EMDR therapy may be more susceptible to misinformation that is inadvertently introduced by the therapist due to reductions in memory vividness. Despite strong theoretical links between eye movements and false memories, few studies have investigated this effect. The current study addressed this issue by attempting to replicate the study by Houben et al. (2018). This study also investigated the working memory account underlying EMDR by comparing eye movements to an alternative dual-task. An initial pilot study comprising a reaction time task established that attentional breathing taxed working memory most comparably to bilateral eye movements. The main study predicted that eye movements would increase susceptibility to misinformation and that eye movements and attentional breathing would lead to comparable reductions in memory vividness and emotionality. 94 students (Mage= 25.74, SDage= 9.68) were recruited to participate in the study at Massey University, Manawatū, New Zealand. Participants viewed a five-minute video depicting a serious car accident. Afterwards, they were randomly assigned to perform either eye movements, attentional breathing, or a control task while simultaneously recalling the car accident. Participants rated the vividness and emotionality of their memory before and after performing the tasks. All participants then received misinformation about the video before completing a recognition test. Results indicated that the misinformation effect was not replicated, with no effect of eye movements on susceptibility to false memories. Findings also suggested that eye movements and attentional breathing were ineffective in reducing the vividness and emotional intensity of the trauma memory. The present study raises questions about the validity of materials and procedures used to instill the misinformation effect. Limitations of the study and key areas for improvement are considered for further investigation.