Over 4 million avoidable hospital admissions result from medication errors (IMS Insitute for Healthcare Informatics, 2013). Human error accounts for 80% of all medical errors (Palmieri, DeLucia, Peterson, Ott, & Green, 2008). Medication administration is a complex process. It is important to understand the cognitive load (CL) of Registered Nurses (RNs) working in an electronic health record environment to identify the risk factors of medication errors. The purpose of this study is to investigate the factors that influence the CL of RNs during medication administration who are working in an electronic health record environment. Simulated medication administration scenarios with varying degrees of multi-tasking were completed with 30 participants. When RNs multi-task during medication administration their CL increases. Furthermore, RNs who have poor sleep quality cannot process high-level tasks as well as those RNs who report a good sleep quality. Future work can limit EEG lead placement to the frontal channels of the EEG. Furthermore, replication of this study with a larger sample and a broader range of competing tasks is indicated.

BCI (Brain Computer Interface) för användning i spel har börjat dyka upp på konsument-marknaden. Dessa använder ofta EEG för att mäta spelarnas avslappningsnivåer och den spelare som lyckas nå högsta meditativa tillstånd samlar poäng. I detta arbete undersöks huruvida det går att använda BCI för mer direkt kontroll av en specifik spelmekanik i kombination med konventionella spelkontroller. För undersökningen har två versioner av ett spel skapats med avsikten att mäta skillnaden i hjärnaktiviteten hos spelare som bara spelar, jämfört med spelare som aktivt försöker åstadkomma ett specifikt sinnestillstånd för att direkt kontrollera en funktion i spelet. På grund av studiens begränsade omfattning kunde inga definitiva slutsatser dras men det finns indikationer på att MindWave, som var utrustningen som användes i denna studie, inte är lämplig som direkt kontrollmetod tillsammans med andra kontroller. Studien skulle kunna fungera som en pilotstudie för en mer omfattande undersökning inom ämnet.

Human to computer interaction only using thoughts is no longer a science fiction topic and recent progress made in this field are astounding. This work shows the creation of a novel upper limb pointing movement performance quantification platform (eCAM test) and its validation on a group of healthy subjects. After that, it shows that functional electrical stimulation (FES) enhances these upper limbs movements performance. Furthermore, this work shows that anodal transcranial direct current stimulation (atDCS) of the cerebellum impacts brain rhythms as well as postural tremor on a patient. Also, the MRI data gathered during this work will allow to better understand the underlying mechanisms of tDCS. Following that, it has been shown that the frequency and complexity of a tapping task increase the postural tremor of the contralateral limb. The same effect has been witnessed for neuromuscular fatigue. All these advances allowed us to place the foundations of a multimodal brain computer interface (BCI) based on sensors fusion. A development phase is now required to create this interface and test it on healthy and sick subjects. / Communiquer avec un ordinateur par le biais de la pensée n'est plus un sujet de science-fiction et les progrès effectués dans le domaine sont ahurissants. Ce travail montre la création d'une nouvelle plateforme de mesure de la performance des mouvements de pointage verticaux (eCAM test) ainsi que sa validation sur une cohorte de sujets sains. Suite à cela, il montre que la stimulation électrique fonctionnelle (FES) améliore la performance de ces mouvements des membres supérieurs. En plus il démontre que la stimulation anodale trancranienne en courant continu (atDCS) du cervelet a un effet sur les rythmes des signaux cérébraux ainsi que sur le tremblement postural d'un patient. De plus des données IRM recueillies durant ce travail permettront de mieux cerner les mécanismes d'action de la stimulation tDCS. Suite à cela, il a été montré que la fréquence et la complexité d'une tâche de tapping augmentent le tremblement postural du membre controlatéral. Le même effet est constaté pour la fatigue musculaire. Toutes ces avancées installent les fondements à la création d'une interface cerveau-machine multimodale basée sur la fusion de senseurs. Une phase de développement est maintenant nécessaire pour établir cette interface et la tester sur des sujets sains et malades. / Doctorat en Sciences biomédicales et pharmaceutiques (Médecine) / info:eu-repo/semantics/nonPublished

Prescription opioid (PO) abuse is a growing public health concern worldwide as evidenced by an increasing number of opioid-related hospital admissions with a striking lack of research examining the neural basis underlying cognitive symptomatology. Drugs of abuse, through their impact on the dopaminergic system, are thought to disrupt the cognitive network regulating impulse control and incentive salience through inhibition of goal-oriented behaviour and drug-induced attentional biases. The objective of the present study is to examine neurocognitive processes in PO abusers (vs. healthy controls) by relying on the enhanced temporal resolution (1ms) of event-related potentials (ERPs) to track information processing abnormalities associated with cognitive control. In a naturalistic clinical study, 16 patients actively using prescription opioids and 16 healthy controls (matched for age, gender, educational level and smoking status) were assessed using a Go/NoGo and cue reactivity paradigm. Analysis revealed no significant differences in N2 or P3 amplitude, measures of inhibitory control, between groups after successful NoGo trials and no significant differences in ERN or Pe amplitude, measures of error processing, between groups after unsuccessful NoGo trials. Cue reactivity analysis of attention-related ERP components in patients demonstrated significantly (p<0.005) smaller P2 amplitudes, indexing the commencement of attentional processing, for drug pictures compared to neutral and affective pictures. Furthermore, stimulus type did not significantly modulate LPP amplitudes, indexing sustained attention, in patients however arousal ratings for drug pictures were positively correlated with LPP amplitudes in patients. These ERP results of altered cognitive control and incentive salience suggest the neural mechanisms underlying these cognitions are affected by chronic opioid abuse. Investigating the cognitive abnormalities experienced by PO abusers is an important factor in understanding the neural correlates of substance abuse and in predicting successful outcomes to ensure the best chance at long-term recovery for addicted individuals.

In this thesis, I sought to determine whether frequency bands in the human electroencephalogram could be used to predict baseball batting performance. Past electroencephalographic (EEG) studies have found that alpha power in the human electroencephalogram predicts subsequent performance. Specifically, Mathewson and colleagues (2012) found that background brain activity, in particular, frontal alpha, had a direct correlation with one’s ability to learn a video game. Here, we decided to see if a similar result would hold true for baseball batting performance. We used a portable electroencephalographic (EEG) data collection system to record EEG data prior to batting practice. Participants sat quietly in a room with the portable EEG unit affixed to their head. Participants then stared in silence at a fixation cross in the center of a computer screen for 30 seconds and then counted backwards from 1000 by 7’s for 30 seconds as a masking task while background EEG was recorded. Player’s were then immediately given live batting practice and with performance judged by three different coaches on four different criteria. The four criteria were: batting mechanics, power, contact, and the batter’s ability to recognize good and bad pitches. Post-hoc, a frequency decomposition was performed on each participant’s EEG data to obtain power in all frequency bands. A correlation analysis of EEG power and batting performance showed that beta power and not alpha power predicted the subsequent performance of the batter. Importantly, a high correlation and significance show that predicting a batter’s performance with a portable EEG system, specifically the MUSE Headband, is highly plausible. / Graduate / 2018-08-09

Traumatic brain injuries (TBI) are one of the leading causes of disability worldwide (Zitnay, 2008), yet one of the least understood neurological conditions (Duncan, 2005). Research has examined short-term deficits; however, less focus has been on the consequences of multiple concussions. Previous electroencephalography (EEG) concussion research has examined the N200 and P300 human event-related potential (ERP) components, yielding inconclusive results (Duncan, Kosmidis & Mirsky, 2005). An ERP component not as frequently examined is the reward positivity, generated by the anterior cingulate cortex (ACC), a region which experiences increased anatomical stress following injury. In this study, 51 students from the University of Victoria took a ‘Concussion Survey’ to determine participant history and groups; no history of concussion, a single injury or multiple injuries (2+). Participants performed an oddball and decision-making task while EEG data was collected. No significant differences were found between groups for the N200, P300 or reward positivity peak latencies or amplitudes. Both concussion groups yielded attenuated peak amplitudes, but no differences existed between the group with a single concussion versus multiple. Unexpectedly, N200 and reward positivity peak latencies were greater in the group with single injuries, compared to those with a history of multiple concussions. This study adds to a continuous line of inconclusive research on the N200 and P300, suggesting minimal cognitive deficits result from concussive injuries. Furthermore, no noticeable differences were observed between groups with a single versus multiple injuries. While the ACC is located in a region of increased stress following TBI, functional deficits impacting the reward positivity may not be as significant as previously hypothesized. Results may be impacted by confounding variables, including not reliably being able to account for time since injury, injury severity and differences in gender dispersion of participants. With concussions on the rise, continued research, particularly longitudinally and within-subjects is critical for the advancement of both TBI prevention and management. / Graduate

Investigations into the cognitive effects of tobacco smoking have generally focused on nicotine and its effect on nicotinic acetylcholine receptors (nAChRs) in the brain. However, it is now known that chronic smokers exhibit robust inhibition of the monoamine oxidase (MAO) enzyme through the actions of non-nicotine components in tobacco smoke. Therefore, the primary aim of this thesis is to elucidate the effects of nicotine and MAO-inhibition on electroencephalographic (EEG) and event-related potential (ERP) measures of cognition. 24 healthy nonsmoking males were administered 75 mg of moclobemide, and chewed 6 mg nicotine gum, in order to simulate the effects of acute smoking. Four experimental conditions included placebo, nicotine, moclobemide, and a combination of nicotine and moclobemide. Early auditory ERPs were used as measures of cognition, such as the auditory P50 sensory gating paired-stimulus paradigm, the acoustic-change-elicited mismatch-negativity (MMN), the novel sound-elicited P3a, and the target sound-elicited P3b. Three minutes of eyes closed EEG were also recorded. Because these ERPs are often identified as biomarkers for schizophrenia, drug effects were also measured after individuals were stratified for low-baseline amplitude of each ERP measure, as a laboratory model of cognitive deficits in schizophrenia. Overall results showed a synergistic improvement in sensory gating via nicotine combined with moclobemide, accompanied by a reduction in theta band power. Nicotine in the absence of moclobemide increased P3b amplitude, accompanied by an increase in alpha2 band power. Moclobemide in the absence of nicotine increased P3a amplitude, accompanied by a decrease in beta2 power. Stratifying participants by placebo amplitude revealed both nicotine and moclobemide exhibited an inverted-U pattern of effect, i.e. showing greater amplitude increases in individuals with the lowest baseline amplitudes. Overall, this thesis demonstrates how these two components of tobacco smoke affect different facets of auditory processing in different ways, with synergistic effects in some paradigms but antagonizing effects in others. Therefore, chronic smokers and schizophrenia patients who seek transient cognitive improvement through smoking may actually experience cognitive detriments overall, possibly contributing to withdrawal symptoms and/or an exacerbation of already-present psychiatric symptoms.

Relationship conflict puts individuals at risk for emotional distress and physical illness. Although many studies in the field have focused on examining cardiovascular, endocrine, and immunological changes associated with relationship conflict, the role of central nervous system processes in relationship functioning remains vastly underexplored. The present study examined frontal electroencephalographic (EEG) alpha asymmetry during discussions of disagreements in romantic partners. Asymmetrical brain activity over the frontal cortex has been conceptualized in the literature as both a trait and state indicator of approach and withdrawal behaviors, with relatively greater left than right frontal activity corresponding to approach behaviors and relatively less left than right frontal activity corresponding to withdrawal behaviors. It was hypothesized that during discussions of disagreements in romantic partners, relatively greater left than right frontal activity would be associated with approach of discussion whereas relatively less left than right frontal EEG asymmetry would be associated with avoidance of discussion. It was also hypothesized that partners would engage in higher level of approach behaviors and exhibit relatively greater left than right frontal activity during discussion of the issue in the relationship that they chose to discuss relative to the issue chosen by their partner. Fifty heterosexual college couples in romantic relationships for at least two months came to the laboratory for a 2.5-hour experimental session, during which self-reported measures were administered, EEG activity was recorded continuously from both partners, and interactions were video-recorded. Participants were asked to engage in 2 discussions of topics on which they disagreed, in counterbalanced order, and each partner was given an opportunity to select an issue to be discussed (Her Issue vs. His Issue). After each discussion, participants were asked to watch a video-recording of their discussions and rate themselves continuously, using a computer mouse, on how much they approached and avoided the discussion. After excluding left-handed participants and data unusable due to equipment failure, data from 25 couples were analyzed. Consistent with the study hypothesis, during discussion of Her Issue, in female partners, greater self-reported rating of approach of discussion was associated with relatively greater left than right frontal activity at F4-F3 and F2-F1 EEG leads. However, there was no significant association between rating of approach of discussion and frontal EEG asymmetry at any of the sites in males during Her Issue, and no effects of rating of approach of discussion on frontal EEG asymmetry at any of the sites during His Issue in either males or females. Consistent with the study hypothesis, both female and male participants evidenced greater rating of approach of discussion during the issue they chose to discuss relative to their partners' issue. Additionally, consistent with the study prediction, males evidenced relatively greater left than right frontal activity measured by the overall asymmetry across 4 regions as well as at F6-F5, F4-F3, and F2-F1 during His Issue relative to Her Issue, and females exhibited greater relative left frontal activity at F8-F7 during Her Issue relative to His Issue. However, there were no significant differences in level of frontal EEG asymmetry measured at other EEG sites. There was a significant positive association between own approach of discussion, as derived from a self-report measure of Demand-Withdraw, and relatively greater left than right frontal activity at F8-F7, F6-F5, and F4-F3 during Her Issue but not His Issue. The current study provided partial support for the association between approach and withdrawal interactions and frontal EEG asymmetry during discussions of disagreements in romantic partners. Future studies should establish whether patterns of changes in frontal EEG activity associated with these interactions have an effect on relationship quality and satisfaction, partners' ability to resolve disagreements, and partners' psychological and physical health.

This dissertation established a state-of-the-art programming tool for designing and training artificial neural networks (ANNs) and showed its applicability to brain research. The developed tool, called NeuralStudio, allows users without programming skills to conduct studies based on ANNs in a powerful and very user friendly interface. A series of unique features has been implemented in NeuralStudio, such as ROC analysis, cross-validation, network averaging, topology optimization, and optimization of the activation function’s slopes. It also included a Support Vector Machines module for comparison purposes. Once the tool was fully developed, it was applied to two studies in brain research. In the first study, the goal was to create and train an ANN to detect epileptic seizures from subdural EEG. This analysis involved extracting features from the spectral power in the gamma frequencies. In the second application, a unique method was devised to link EEG recordings to epileptic and non-epileptic subjects. The contribution of this method consisted of developing a descriptor matrix that can be used to represent any EEG file regarding its duration and the number of electrodes. The first study showed that the inter-electrode mean of the spectral power in the gamma frequencies and its duration above a specific threshold performs better than the other frequencies in seizure detection, exhibiting an accuracy of 95.90%, a sensitivity of 92.59%, and a specificity of 96.84%. The second study yielded that Hjorth’s parameter activity is sufficient to accurately relate EEG to epileptic and non-epileptic subjects. After testing, accuracy, sensitivity and specificity of the classifier were all above 0.9667. Statistical tests measured the superiority of activity at over 99.99 % certainty. It was demonstrated that 1) the spectral power in the gamma frequencies is highly effective in locating seizures from EEG and 2) activity can be used to link EEG recordings to epileptic and non-epileptic subjects. These two studies required high computational load and could be addressed thanks to NeuralStudio. From a medical perspective, both methods proved the merits of NeuralStudio in brain research applications. For its outstanding features, NeuralStudio has been recently awarded a patent (US patent No. 7502763).

Perceptual capacity and selection in attention have for long been an interest in cognitive science, with early theories of early selection to late selection. Hearing is an important subject to investigate when it comes to attention and early auditory processing can be investigated by using auditory steady state responses (ASSRs). Studies on ASSRs to irrelevant sounds have investigated the 40 Hz ASSR and concluded no effect of load. As studies on temporal activation of ASSRs indicate that lower and higher frequencies activate different stages of the auditory pathway, there is a need to investigate other frequencies than the 40 Hz. This study investigated the 20 Hz and 80 Hz amplitude modulations using EEG. The visual stimuli were a rapid stream of letters and varied between no load, low load, and high load. The auditory stimuli were an amplitude-modulated tone with a carrier frequency of 500 Hz, with three varying modulation frequencies: 20 Hz, 40 Hz, and 80 Hz. Load level and amplitude modulation alternated over 18 blocks. The statistical analysis was comprised of t tests and Bayes Factor. Results provided support for the null hypothesis for the 20 Hz frequency but were inconclusive for the 40 Hz and 80 Hz frequency. More data is needed to give a conclusion for effect of load for the 40 Hz and 80 Hz frequency. As we did not have enough data, we cannot say anything about the temporal activation of ASSRs in the brain.