It has recently been demonstrated that the presentation of a rare target in a visual oddball paradigm induces a prolonged inhibition of microsaccades. In the field of electrophysiology, the amplitude of the P300 component in event-related potentials (ERP) has been shown to be sensitive to the stimulus category (target vs. non target) of the eliciting stimulus, its overall probability, and the preceding stimulus sequence. In the present study we further specify the functional underpinnings of the prolonged microsaccadic inhibition in the visual oddball task, showing that the stimulus category, the frequency of a stimulus and the preceding stimulus sequence influence microsaccade rate. Furthermore, by co-recording ERPs and eye-movements, we were able to demonstrate that, despite being largely sensitive to the same experimental manipulation, the amplitude of P300 and the microsaccadic inhibition predict each other very weakly, and thus constitute two independent measures of the brain’s response to rare targets in the visual oddball paradigm.

The direction in which another is looking at triggers a spontaneous orienting of attention towards gaze direction in the viewer. However, whether the facial expression displayed by the gazing individual modulates this attention orienting is unclear. In this thesis, the modulation of gaze-oriented attention with facial expressions was explored in non-anxious individuals at the behavioral level and at the neural level using Event-Related Potentials (ERP). In the gaze-cueing paradigm used, a dynamic face cue averting gaze and expressing an emotion was presented, followed by a lateral, to-be-localized target. At the behavioral level, a faster response to targets appearing at the gazed-at location (congruent targets) than to targets appearing opposite to the gazed-at location (incongruent targets) was observed (Chapters 3-5). This so-called Gaze Orienting Effect (GOE) was enhanced with fearful, angry and surprised expressions relative to neutral and happy expressions and was driven by emotional differences in response speed to congruent targets (Chapters 3-5). These effects could not be attributed to better discrimination of those emotions when presented with an averted gaze (Chapter 2). These results confirm the impact of fear and surprise on gaze-oriented attention in non-anxious individuals and demonstrate, for the first time, a similar impact for angry expressions. All the emotions enhancing the GOE signal an evolutionary relevant stimulus in the periphery, are threat-related and carry a negative valence, which suggests that one of these attributes (or all combined) is driving the emotional modulation of gaze-oriented attention (surprise is treated like fear in the context of fearful expressions). In Chapter 4, the effect of the dynamic cue sequence on these GOE modulations was investigated. An emotional modulation of the GOE was found only when the gaze shift preceded the emotional expression, but not when the emotion was expressed before gaze shift or when expression and gaze shift were simultaneous. These results highlight the importance of using a sequence closer to real life situations (we usually orient attention before reacting to an object in the environment) in studying the modulation of the GOE with emotions. At the neural level, we investigated the ERPs associated with gaze-oriented attention at target presentation and at cue presentation (Chapters 3 and 5). Confirming previous reports, the amplitude of a target-triggered P1 ERP component was larger in the congruent than in the incongruent condition, reflecting enhanced processing of gaze-congruent targets. In addition, cue-triggered ERPs previously observed in response to arrow cues, were investigated. An Early Directing Attention Negativity (EDAN) and an Anterior Directing Attention Negativity (ADAN) were found, indexing respectively attention-orienting to the cued location and maintenance of attention at the cued location. This is the first study to report both EDAN and ADAN components in response to gaze cues. These results show clear markers of attention orienting by gaze at the neural level, during both cue and target processing. Neither EDAN nor ADAN was modulated by emotion. The congruency effect on P1 was enhanced for fearful, surprised and happy faces compared to neutral faces in Chapter 3 but no differences between the emotions were found in Chapter 5. Thus, the emotional modulation of the brain processes involved in gaze-oriented attention is very weak and protracted or occurs mainly between target onset and response to target. The relationships between participants’ autistic traits and their emotional modulation of gaze-oriented attention were also investigated. Results showed a negative correlation with the GOE to happy upright faces and with the P1 congruency effect, which suggests that individuals with more severe autistic traits are less sensitive to the impact of social emotions like joy. The implication of these results for attention orienting in general and for individuals with Autism Spectrum Disorder is discussed. Together, the findings reported in this thesis clarify the behavioral and neural processes involved in gaze oriented attention and its modulation by facial expression in addition to demonstrating a relationship between gaze oriented attention, its modulation with social emotions and autistic traits.

Evidence suggests that emotion affects memory often yielding enhanced recall and recognition of stimuli with emotional content. The nature of the relationship between emotion and memory for words has been particularly difficult to parse in part because of the stimulus characteristics. For example, emotional words tend to engender greater levels of physiological and psychological arousal, which have also been shown to enhance memory. Inter item relatedness has also been suggested as playing a part in the observed effects (i.e., emotional words belong to a closed semantic category compared to neutral words and are therefore easier to remember). While the enhancement of memory for emotional material has been demonstrated across a variety of stimuli and experimental conditions, the neural underpinnings of these effects remain unclear. The Old/New effect is an event related potential finding where electrophysiologic waveforms elicited by previously presented stimuli (i.e., old) are more positive going than those elicited by stimuli that were not previously presented (i.e., new). A few prior studies have investigated Old/New effects for emotional words, mostly comparing negative to neutral words and failing to equate their stimuli for the crucial confounding effects of arousal and inter item relatedness. The present study employed event related potentials to investigate recognition memory for words of positive, negative, and neutral valences in a sample of thirty healthy college undergraduates. It was predicted that positive and negative words would yield greater participant accuracy, response bias and Old/New effects in comparison to neutral words. The observed results yielded some variability in support for all of the hypotheses and predictions that were made a priori. Possible explanations for these results are discussed and directions for future research recommended.

The direction in which another is looking at triggers a spontaneous orienting of attention towards gaze direction in the viewer. However, whether the facial expression displayed by the gazing individual modulates this attention orienting is unclear. In this thesis, the modulation of gaze-oriented attention with facial expressions was explored in non-anxious individuals at the behavioral level and at the neural level using Event-Related Potentials (ERP). In the gaze-cueing paradigm used, a dynamic face cue averting gaze and expressing an emotion was presented, followed by a lateral, to-be-localized target. At the behavioral level, a faster response to targets appearing at the gazed-at location (congruent targets) than to targets appearing opposite to the gazed-at location (incongruent targets) was observed (Chapters 3-5). This so-called Gaze Orienting Effect (GOE) was enhanced with fearful, angry and surprised expressions relative to neutral and happy expressions and was driven by emotional differences in response speed to congruent targets (Chapters 3-5). These effects could not be attributed to better discrimination of those emotions when presented with an averted gaze (Chapter 2). These results confirm the impact of fear and surprise on gaze-oriented attention in non-anxious individuals and demonstrate, for the first time, a similar impact for angry expressions. All the emotions enhancing the GOE signal an evolutionary relevant stimulus in the periphery, are threat-related and carry a negative valence, which suggests that one of these attributes (or all combined) is driving the emotional modulation of gaze-oriented attention (surprise is treated like fear in the context of fearful expressions). In Chapter 4, the effect of the dynamic cue sequence on these GOE modulations was investigated. An emotional modulation of the GOE was found only when the gaze shift preceded the emotional expression, but not when the emotion was expressed before gaze shift or when expression and gaze shift were simultaneous. These results highlight the importance of using a sequence closer to real life situations (we usually orient attention before reacting to an object in the environment) in studying the modulation of the GOE with emotions. At the neural level, we investigated the ERPs associated with gaze-oriented attention at target presentation and at cue presentation (Chapters 3 and 5). Confirming previous reports, the amplitude of a target-triggered P1 ERP component was larger in the congruent than in the incongruent condition, reflecting enhanced processing of gaze-congruent targets. In addition, cue-triggered ERPs previously observed in response to arrow cues, were investigated. An Early Directing Attention Negativity (EDAN) and an Anterior Directing Attention Negativity (ADAN) were found, indexing respectively attention-orienting to the cued location and maintenance of attention at the cued location. This is the first study to report both EDAN and ADAN components in response to gaze cues. These results show clear markers of attention orienting by gaze at the neural level, during both cue and target processing. Neither EDAN nor ADAN was modulated by emotion. The congruency effect on P1 was enhanced for fearful, surprised and happy faces compared to neutral faces in Chapter 3 but no differences between the emotions were found in Chapter 5. Thus, the emotional modulation of the brain processes involved in gaze-oriented attention is very weak and protracted or occurs mainly between target onset and response to target. The relationships between participants’ autistic traits and their emotional modulation of gaze-oriented attention were also investigated. Results showed a negative correlation with the GOE to happy upright faces and with the P1 congruency effect, which suggests that individuals with more severe autistic traits are less sensitive to the impact of social emotions like joy. The implication of these results for attention orienting in general and for individuals with Autism Spectrum Disorder is discussed. Together, the findings reported in this thesis clarify the behavioral and neural processes involved in gaze oriented attention and its modulation by facial expression in addition to demonstrating a relationship between gaze oriented attention, its modulation with social emotions and autistic traits.

Diversos resultats experimentals, tant en animals com en humans han assenyalat la rellevància dels ritmes corticals en el processament cognitiu cerebral. Aquests resultats mostren com l'activitat neuronal oscil.latòria representa un bon marc de treball per entendre com els grups neuronals coordinen la seva activitat per tal de respondre amb efectivitat davant situacions funcionals específiques. Tots ells suggereixen que l'activitat neuronal oscil.latòria pot representar un enllaç determinant d'unió entre el dinamisme cerebral amb els processos cognitius.En aquest sentit, un cos creixent d'evidències experimentals dóna suport a la perspectiva que les oscil.lacions de l'EEG són subjacents a la generació dels Potencials associats a un Esdeveniment (ERPs). Aquests resultats mostren com la naturalesa oscil.latòria de l'activitat neuronal resultant en una interacció amb l'esdeveniment entrant manifesta diversos patrons de resposta que poden ser estudiats mitjançant la modulació de l'espectre de potència i la realineació de la fase espectral. Aquest dos tipus de mesures ofereixen informació complementària de la dinàmica cortical evocada i, per tant, permeten aprofundir en l'estudi dels mecanismes neuronals subjacents a respostes cerebrals evocades en situacions experimentals específiques. Malgrat tot, actualment encara no és clara la implicació d'aquests processos neuronals oscil.latoris en els ERPs.El present treball aporta evidències experimentals que els patrons oscil.latoris associats a certs ERPs auditius poden ser diferenciats, mostrant com alguns ERPs comparteixen modulacions d'espectre de potència i realineació de fase concurrent, mentre que altres apareixen únicament per la concentració de fase de components freqüencials que es produeix com a conseqüència de l'entrada d'un esdeveniment. En relació a la hipòtesi de la participació de mecanismes neuronals oscil.latoris en l'aparició de certs ERPs, els resultats que aquí es mostren donen suport a que, efectivament, les oscil.lacions neuronals de certs components freqüencials hi tenen un paper determinant.En conclusió, aquest treball posa de relleu que l'anàlisi de la dinàmica témporo-freqüencial cerebral en respostes neuronals evocades (ERPs) estudiades assaig-assaig, permet posar de manifest fenòmens neuronals que queden encoberts amb els procediments clàssics d'estudi dels ERPs, i que poden ser de rellevància per tal d'establir les bases neurofisiològiques de l'activitat cerebral en relació a funcions neuronals específiques. Els resultats aquí presentats aporten evidències experimentals a la perspectiva d'acord amb la qual la dinàmica cerebral subjacent a certes funcions està fonamentada en activitat neuronal oscil.latòria, pel que permet estudiar els mecanismes d'interacció entre estats neuronals espontanis (EEG) i patrons de desposta neuronal evocada (ERPs).

xv, 169 p. ; ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Improvements in neuroimaging techniques have made it possible to answer questions regarding the neural organization for the processing of syntax in normal participants. In this series of experiments we examined the effects of linguistic proficiency and age of second language acquisition on neural organization for syntactic processing. We examined these factors using two complementary methodologies: event-related potentials (ERPs), which affords a temporal resolution on the order of milliseconds, and functional magnetic resonance imaging (fMRI), with spatial resolution on the order of millimeters. In order to compare results across methodologies, we used an auditory syntactic violation paradigm with similar experimental parameters in each methodology. In Chapter II we examined neural organization for syntactic processing using ERPs in monolingual native speakers of higher and lower proficiency and found that violations elicited an early onset (100 ms) anterior negativity (EOAN) followed by a later positivity (P600) in all participants. Compared to lower proficiency participants, higher proficiency participants showed an EOAN that was more focal spatially and temporally, and showed a larger P600. These results were supported by a correlational analysis of a larger group of monolingual native speakers with a wide range of proficiency scores. This analysis also found a relationship between childhood socioeconomic status and the recruitment of the EOAN over left hemisphere sites, raising the hypothesis that effects of childhood experience may endure into adulthood. In Chapter III we examined the effects of age of acquisition on syntactic processing by recruiting a group of late learners of English who were matched for proficiency with a group of monolingual native speakers from Chapter II. While in native speakers violations elicited a robust EOAN, this effect was absent in the late learner group, suggesting that early language exposure is important for the recruitment of resources reflected in this effect and independently of proficiency. In Chapter IV we gathered ERP and fMRI data from monolingual native speakers and found proficiency differences in the recruitment for syntactic processing of left inferior frontal and posterior regions. We linked proficiency-related modulations in the different ERP syntactic effects to specific fMRI activations indexing syntactic processing. / Adviser: Helen J. Neville

In recent years, Internal Control has become the focus of attention every time there is a notable scandal in the corporate world. An effective internal control system can prevent an organisation from fraud and errors, and provide an organisation with assurance and competitive advantages. It is argued that in order to have a robust internal control system, an integrated system, such as an Enterprise Resource Planning (ERP) system is needed. ERP systems have the ability to control user access and facilitate the separation of duties, which is one of the most common internal control mechanisms used in order to deter fraud within financial systems. Moreover, there are other factors that can provide support for effective internal control systems. This thesis aims to explain how ERP success, organisational and ERP factors affect the effectiveness of internal control procedures. In particular, this thesis develops and validates a research model with empirical evidence collected in the context of the Saudi Arabia business environment. In order to achieve the research aim, this research identifies four key propositions derived from the existing literature to establish the relationships between organisational factors, ERP factors, ERP success and effectiveness of internal control procedures. An exploratory study is used to initially test the four propositions. The findings indicate that different companies follow different requirements that mainly depend on ownership. Additionally, the study indicates that the eight components of the Committee of Sponsoring Organizations of the Treadway Commission’s (COSO) Enterprise Risk Management framework are considered by the companies investigated, however there are variations regarding their level of consideration. The findings suggest that further study is needed to explain the impact of ERP success on internal control and to measure the effect of the organisational and ERP factors. Based on the four propositions, four hypotheses are developed and tested in a quantitative study. A questionnaire is constructed and sent to 217 Saudi ERP-implemented companies. 110 valid responses are received. Partial Least Squares Structural Equation Modelling (PLS-SEM) is adopted for data analysis and hypothesis testing. The results suggest that the maturity of the ERP systems, formalisation and centralisation can impact on the success of ERP systems. Prospectors’ strategy, organisational culture and management support are positively related to the effectiveness of internal control procedures. The study results show a positive significant relationship between the success of ERP systems and effectiveness of internal control procedures. This research contributes to the knowledge at different levels. At the theoretical level, it develops and validates a theoretical framework that links the ERP system success to the effectiveness of internal control procedures. At the methodological level, unlike many of previous studies, this study adopts multiple data collection methods, and a powerful statistical technique, PLS-SEM to generate more robust outcomes. Finally, at the practice level, the study is conducted in Saudi Arabia, which is different from the developed countries in many aspects, such as internal control regulations and taxation system. Thus, the findings can be beneficial to Saudi organisations as well as other Middle-East countries.

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Aggression and violence are social behaviors that exact a significant toll on human societies. Individuals with aggressive tendencies display deficits in effortful control, particularly in affectively charged situations. However, not all individuals with poor effortful control are aggressive. This study uses event-related potentials (ERPs) to decompose the chronology of cognitive functions underlying the link between effortful control and aggression. Specifically, this study investigates which ERPs moderate the effortful control - aggression association. We examined three successive ERP components (P2, N2 and P3) for stimuli that required effortful control. Results indicated that N2 activation, but not P2 or P3 activation, moderated the relationship between effortful control and aggression. These effects were present in negative and neutral contexts. This moderating effect was consistent with previous studies linking neural processing efficiency with reduced activation during cognitive control tasks. Our results suggest that efficient cognitive processing moderates the association between effortful control and aggression.

Language is a multimodal process with visual and auditory cues playing important roles in understanding speech. A well-controlled paradigm with audiovisually matched and mismatched syllables is often used to capture audiovisual (AV) speech processing. The ability to detect and integrate mismatching cues shows large individual variability across development and is linked to later language in typical development (TD) and social abilities in autism spectrum disorder (ASD). However, no study has used a multimethod approach to better understand AV speech processing in early development. The studies’ aims were to examine behavioral performance, gaze patterns, and neural indices of AV speech in: 1) TD preschoolers (N=60; females=35) and 2) infants at risk for developing ASD (high-risk, HR; N=37; females=10) and TD controls (low-risk, LR; N=42; females=21). In Study 1, I investigated preschoolers’ gaze patterns and behavioral performance when presented with matched and mismatched AV speech and visual-only (lipreading) speech. As hypothesized, lipreading abilities were associated with children’s ability to integrate mismatching AV cues, and children looked towards the mouth when visual cues were helpful, specifically in lipreading conditions. Unexpectedly, looking time towards the mouth was not associated with the children’s ability to integrate mismatching AV cues. Study 2 examined how visual cues of AV speech modulated auditory event-related potentials (ERPs), and associations between ERPs and preschoolers’ behavioral performance during an AV speech task. As hypothesized, the auditory ERPs were attenuated during AV speech compared to auditory-only speech. Additionally, individual differences in their neural processing of auditory and visual cues predicted which cue the child attended to in mismatched AV speech. In Study 3, I investigated ERPs of AV speech in LR and HR 12-month-olds and their association with language abilities at 18-months. Unexpectedly, I found no group differences: all infants were able to detect mismatched AV speech as measured through a more negative ERP response. As hypothesized, more mature neural processing of AV speech integration, measured as a more positive ERP response to fusible AV cues, predicted later language across all infants. These results highlight the importance of using multimethod approaches to understand variability in AV speech processing at two developmental stages. / 2021-11-12T00:00:00Z