Maladaptive decision-making that typifies drug addiction could reflect alterations in cognitive and emotional processing when these individuals are faced with choices. Even if this is true, it is not clear whether these deficits are a cause or a consequence of chronic drug use. The following experiments were designed to determine the effect of acute alcohol intoxication on affective processing in healthy individuals, as measured through a variety of behaviours. In the first experiment, acute alcohol intoxication did not impair performance on a task that recruits the orbitofrontal cortex, a key area for decision-making. In the second experiment examining preference formation, there was a clear dissociation between alcohol’s effect on implicit and explicit memory: acute intoxication impaired explicit memory, while leaving implicit learning intact. In a subsequent experiment, both alcohol and placebo groups showed altered physiological and subjective responses to a psychosocial stressor. Although acute alcohol intoxication did not affect risk-taking, an individual variable (tension-reactivity) moderated performance on this laboratory task. This experiment also revealed a relationship between stress-reactivity and subsequent risk-taking, one explanation being that high levels of cortisol increased individual sensitivity to task outcomes. Finally, an analysis of the accumulated information on drinking rates, impulsivity, and drug use suggests that female drinking rates may be approaching the levels reported by males. There were also significant differences in sensitivity to alcohol’s effects when participants were intoxicated in the lab. Heavy drinkers showed a greater sensitivity to the pleasurable effects of alcohol despite feeling less intoxicated and desiring more alcohol than other individuals. These combined effects could put heavy drinkers at greater risk for alcohol-related problems. Taken as a whole, these studies suggest that individual factors play a stronger role in moderating affective processing than do the direct pharmacological effects of alcohol. / Thesis (Ph.D, Psychology) -- Queen's University, 2008-03-20 14:29:40.722

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Thesis (PhD (Psychiatry))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Pregnancy is often accompanied by distressing psychological symptoms such as anxiety. These symptoms may result from changes in cognitive-affective processing, which in turn reflect hormonal changes during this time. However, findings on associations between psychological distress, cognitive-affective changes and hormones have been inconsistent. Furthermore, few studies have investigated the neural circuitry underlying distress and cognitive-affective processing in pregnancy. The prefrontal cortex (PFC) plays a specific role in regulating emotion. Determining the relationship between these changes in cognitive-affective processing and in prefrontal circuitry is important, given the high prevalence of depressive and anxiety disorders in pregnancy. The overall objective of this study was to investigate distressing psychological symptoms and their association with cognitive-affective processes and neurobiological changes over the course of pregnancy. Pregnant women with low risk singleton pregnancies were recruited from Midwife Obstetric Units in the Western Cape. Non-pregnant healthy controls were also recruited from the same demographic area. Distress levels were assessed using the K-10, Spielberger State -Trait Inventory, and Perceived Stress Scale. Subjectively experienced cognitive ability was asked about. Objective cognitive ability was assessed using standardized neuropsychological tests. Selective attention to threat such as fear and anger was assessed using a Facial Stroop Task. Neural circuitry was assessed using Near-Infrared Spectroscopy while viewing dynamic emotional facial expressions of threat (Emotion Recognition Task). Glucocorticoid (cortisol) and gonadal hormonal levels (estrogen, progesterone, and testosterone) were also determined at each trimester of pregnancy. Associations between distressing psychological symptoms, cognitive-affective processes and neurobiology were assessed using standard statistical methods. The main findings to emerge from this research were that, 1. pregnant women had significantly higher trait anxiety at trimester 2, compared to trimester 1 of pregnancy; 2. compared to non-pregnant women, pregnant women paid significantly more attention to fearful faces across trimesters, suggesting altered cognitive-affective processing in pregnancy compared to non-pregnancy; 3. pregnant women demonstrated significantly increased PFC activation in response to fearful and angry faces (all trimesters) that was particularly evident at trimester 2; 4. the PFC activation was, across trimesters, significantly correlated with distress and selective attention to threat; and 5. the PFC activation was, across trimesters, also significantly associated with increased glucocorticoid and gonadal hormone levels. The main findings of this study are consistent with previous literature insofar as distress has previously been associated with altered cognitive-affective processing and prefrontal cortex activation, but extend it by showing that emotional regulation is altered in pregnancy compared to the non-pregnant state. These data provide an important insight into distressing psychological symptoms and their associations with cognitive-affective processes, and changes in neural circuitry and in hormone levels in pregnancy. These findings are also the first to show that structures involved in emotional processing (e.g. the PFC) also play a role in the regulation of affect in pregnancy. Future research should explore the causal mechanisms underlying altered emotional regulation in pregnancy, and include pregnant women that are clinically depressed or anxious as comparison subjects. / AFRIKAANSE OPSOMMING: Swangerskap word dikwels geassosieër met stres-veroorsakende sielkundige simptome soos angstigheid. Hierdie simptome mag die gevolg wees van veranderinge in kognitief-affektiewe prosessering, wat op sy beurt mag dui op hormonale veranderinge. Bevindinge oor assosiasies tussen sielkundige stres, kognitief-affektiewe prosessering en hormone is tot dusver onbeslis. Voorts was min studies gerig op die neurologiese meganika onderliggend aan stres en kognitief-affektiewe prosessering tydens swangerskap. Die prefrontale korteks (PFK) het 'n spesifieke rol in die regulering van emosie. Die bepaling van spesifieke assosiasies tussen veranderinge in kognitief-affektiewe prosessering en in prefrontale regulering is belangrik, gegewe die hoë voorkoms van toestande soos depressie en angssteurings tydens swangerskap. Die doel met hierdie studie was 'n ondersoek na assosiasies tussen stres-veroorsakende sielkundige simptome, kognitief-affektiewe prosesse en neurobiologie tydens swangerskap. Swanger vroue met lae risiko enkel-swangerskappe is gewerf by klinieke in Wes-Kaapland. Gesonde nie-swanger vroue is uit dieselfde omgewing gewerf as kontroles. Angs-vlakke is geevalueer met behulp van die K-10; die Spielberger State-Trait Inventory en die Perceived Stress Scale. Vrae is tydens ondersoeke gevra oor subjektief-ervaarde kognitiewe vermoë. Voorts is kognitiewe vermoë geëvalueer met behulp van gestandardiseerde neurosielkundige toetse. Hierbenewens is selektiewe aandag aan bedreigende gesigte wat vrees en woede toon, geëvalueer met behulp van 'n Facial Stroop Task. Neurologiese funksie is geëvalueer met gebruik van Na-Infrarooi Spektroskopie terwyl dinamiese bedreigende emosionele gesigsuitdrukkings vertoon is (Emotion Recognition Task). Gluko-kortikoïed (kortisol) en geslagshormoonvlakke (estrogeen, progesteroon, en testosteroon) is gemeet tydens elke trimester. Verwantskappe tussen stresvolle simptome, kognitief-affektiewe prosessering en neurobiologie is geëvalueer met standaard statistiese metodes. Die hoofbevindinge het op die volgende gedui: 1. swanger vroue het betekenisvolle hoër trait angs-vlakke getoon in trimester 2, vergeleke met trimester 1; 2. vergeleke met nie-swanger vroue, het swanger vroue beduidend meer aandag geskenk aan angstige gesigsuitdrukkings tydens elke trimester wat mag dui op veranderde kognitief-affektiewe prosessering tydens swangerskap vergeleke met nie-swangerskap; 3. swanger vroue het beduidend hoër PFK aktivering getoon teenoor angstige en kwaai gesigte in alle trimesters, maar veral in trimester 2; 4. swanger vroue se PFK aktivering het, in alle trimesters, beduidend gekorreleer het met stres-vlakke en selektiewe aandag teenoor bedreigende stimuli; en 5. swanger vroue se PFK aktivering het, in alle trimesters, ook 'n beduidende verwantskap getoon met verhoogde gluko-kortikoïed en geslagshormoonvlakke. Die hoofbevindinge in hierdie studie stem ooreen met vorige literatuur wat aangedui het dat daar 'n verband is tussen stres en veranderinge in kognitief-affektiewe prosessering en in prefrontale korteks aktivering, maar dui verder op veranderinge in emosionele regulering tydens swangerskap vergeleke met nie-swangerskap. Die data bied 'n belangrike insig in stres-veroorsakende sielkundige simptome; hul verwantskap met kognitief-affektiewe prosesse; veranderinge in neurologiese netwerke; en veranderinge in hormoonvlakke tydens swangerskap. Sover bekend is dit ook die eerste keer bevind dat strukture wat betrokke is by emosionele prosessering (bv. die PFK), ook betrokke is in die regulering van emosie tydens swangerskap. Dit is belangrik dat toekomstige navorsing die onderliggende meganismes wat veranderinge in emosionele regulering teweeg bring, ondersoek. Verdere ondersoek om hierdie veranderinge in swanger depressie-lyers of diegene met angssteurings te vergelyk is ook van belang.

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Um fator relevante para a aceitação de metáforas de mundos virtuais 3D como interfaces homem máquina é a supressão do fator estranheza. Tal fator decorre da percepção de comportamentos não naturais entre as representações de usuários (avatares) e robôs (NPCs Non Playable Characters) nestes ambientes virtuais e acontece, principalmente, devido a diferenças sutís entre o comportamento esperado de um ser humano e o apresentado pelas representações virtuais (avatares). Ao conjunto de comportamentos exibidos denominamos persona. Assim, uma maneira de reduzir a barreira de estranheza entre usuários interagindo em mundos virtuais 3D é fazendo com que suas representações (avatares) tenham personas convincentes. Os seres humanos tem suas personas regidas por seus tratos emocionais. As interações com o ambiente e com outros seres humanos fornecem estímulos que modificam o estado emocional com relação ao estado de equilíbrio e, consequentemente, alteram o comportamento exterior observado. O estado emocional de equilíbrio pode ser obtido através da análise de corpo de comunicação em linguagem natural do usuário. Neste trabalho é defendida a tese de que através da análise do corpo das interações em linguagem natural de usuários nas mídias sociais é possível estabelecer um modelo de personalidade e persona que pode ser transposto para a representação dos usuários nem mundos virtuais 3D, de forma que as representações tenham comportamentos tais que reduzem o fator de estranheza. O modelo faz uso das interações recentes nas mídias sociais e das interações nos mundos virtuais 3D para determinar o estado emocional imediato e o comportamento instantâneo e é coerente com o paradigma do modelo OCC. Também é demonstrado que este modelo é evolutivo: pela análise contínua do corpo da comunicação é acompanhada a evolução da personalidade do usuário, bem como se adequa continuamente sua persona. Os traços de personalidade são analizados no modelo Big Five (Neuroticism, Extraversion, Agreeableness, Conscientiousness, Openness) e operacionalizados no modelo PAD (Personality, arousal, dominance). O modelo constrói um campo de personalidade, no espaço PAD, de tal forma que na ausência de excitação o estado emocional do avatar fica em repouso no centro deste campo. As excitações movimentam o estado ao longo dos eixos PAD e provocam mudanças no comportamento observado. A correspondência entre as mudanças de comportamento do avatar e o movimento do estado do usuário no campo emocional aumenta a concordância entre comportamento esperado e observado, reduzindo o fator de estranheza. / A key factor for the acceptance of 3D virtual world mataphor as human machine interface is the suppression of the strangeness factor, which appears due the perception of non natural behaviour in representations of users (avatars) and bots (NPCs). Such perception raises mostly due to subtle differences in expected behavior for a human being and observed behavior in virtual representations (avatars and NPCs). In this work we will call persona the set of exhibited behaviors. Thus, a way of diminishing the strangeness valley is by supplying avatars with convincing personas. Human beings rule their personas with intermediation of their emotional traits. Interactions with environment and other beings supply stimuli that change the emotional state from the equilibrium situation and, consequently, change observed behavior. Idle emotional state can be determined through natural language communication corpora analysis. In this thesis we state that through the analysis of user interactions in social media it is possible to establish a model of personality and persona that can be transposed to their representation in 3D virtual worlds, so such representation exhibits behavior that minimize strangeness. The model uses recent interations of user in social media and his interactions inside the 3D virtual world to establish current behavior and is coherent with OCC paradigm. It is also demonstrated that such model is evolutive: by the continuous analysis of communication corpora the user personality behavior is updated and its persona is continually adjusted. Personality traits are analysed in the Big Five model (neuroticism, agreeableness, conscientiousness, openness) and operationalized in the PAD model (personality, arousal, dominance). A personality field is built such as in the absence of inputs, emotional state lies in the center of this field. Inputs move state along PAD axes and cause changes in the observed behavior. Correspondence between avatar behavior changes and state changes of user regarding its emotional field enhance the compliance between expected and observed behavior, reducing strangeness.

Um fator relevante para a aceitação de metáforas de mundos virtuais 3D como interfaces homem máquina é a supressão do fator estranheza. Tal fator decorre da percepção de comportamentos não naturais entre as representações de usuários (avatares) e robôs (NPCs Non Playable Characters) nestes ambientes virtuais e acontece, principalmente, devido a diferenças sutís entre o comportamento esperado de um ser humano e o apresentado pelas representações virtuais (avatares). Ao conjunto de comportamentos exibidos denominamos persona. Assim, uma maneira de reduzir a barreira de estranheza entre usuários interagindo em mundos virtuais 3D é fazendo com que suas representações (avatares) tenham personas convincentes. Os seres humanos tem suas personas regidas por seus tratos emocionais. As interações com o ambiente e com outros seres humanos fornecem estímulos que modificam o estado emocional com relação ao estado de equilíbrio e, consequentemente, alteram o comportamento exterior observado. O estado emocional de equilíbrio pode ser obtido através da análise de corpo de comunicação em linguagem natural do usuário. Neste trabalho é defendida a tese de que através da análise do corpo das interações em linguagem natural de usuários nas mídias sociais é possível estabelecer um modelo de personalidade e persona que pode ser transposto para a representação dos usuários nem mundos virtuais 3D, de forma que as representações tenham comportamentos tais que reduzem o fator de estranheza. O modelo faz uso das interações recentes nas mídias sociais e das interações nos mundos virtuais 3D para determinar o estado emocional imediato e o comportamento instantâneo e é coerente com o paradigma do modelo OCC. Também é demonstrado que este modelo é evolutivo: pela análise contínua do corpo da comunicação é acompanhada a evolução da personalidade do usuário, bem como se adequa continuamente sua persona. Os traços de personalidade são analizados no modelo Big Five (Neuroticism, Extraversion, Agreeableness, Conscientiousness, Openness) e operacionalizados no modelo PAD (Personality, arousal, dominance). O modelo constrói um campo de personalidade, no espaço PAD, de tal forma que na ausência de excitação o estado emocional do avatar fica em repouso no centro deste campo. As excitações movimentam o estado ao longo dos eixos PAD e provocam mudanças no comportamento observado. A correspondência entre as mudanças de comportamento do avatar e o movimento do estado do usuário no campo emocional aumenta a concordância entre comportamento esperado e observado, reduzindo o fator de estranheza. / A key factor for the acceptance of 3D virtual world mataphor as human machine interface is the suppression of the strangeness factor, which appears due the perception of non natural behaviour in representations of users (avatars) and bots (NPCs). Such perception raises mostly due to subtle differences in expected behavior for a human being and observed behavior in virtual representations (avatars and NPCs). In this work we will call persona the set of exhibited behaviors. Thus, a way of diminishing the strangeness valley is by supplying avatars with convincing personas. Human beings rule their personas with intermediation of their emotional traits. Interactions with environment and other beings supply stimuli that change the emotional state from the equilibrium situation and, consequently, change observed behavior. Idle emotional state can be determined through natural language communication corpora analysis. In this thesis we state that through the analysis of user interactions in social media it is possible to establish a model of personality and persona that can be transposed to their representation in 3D virtual worlds, so such representation exhibits behavior that minimize strangeness. The model uses recent interations of user in social media and his interactions inside the 3D virtual world to establish current behavior and is coherent with OCC paradigm. It is also demonstrated that such model is evolutive: by the continuous analysis of communication corpora the user personality behavior is updated and its persona is continually adjusted. Personality traits are analysed in the Big Five model (neuroticism, agreeableness, conscientiousness, openness) and operationalized in the PAD model (personality, arousal, dominance). A personality field is built such as in the absence of inputs, emotional state lies in the center of this field. Inputs move state along PAD axes and cause changes in the observed behavior. Correspondence between avatar behavior changes and state changes of user regarding its emotional field enhance the compliance between expected and observed behavior, reducing strangeness.

Patients with MDD demonstrate impairments in various components of affective processing, which are believed to persist in the remitted phase of the illness and are believed to underlie the vulnerability for future relapse. Despite advances in neuropsychiatry, the neuroanatomical site of action of various treatment modalities remains unclear, leaving clinicians without an algorithm to guide optimal treatment selection for individual patients. This thesis sought to characterize differences in brain activation during affective processing between MDD treatment responders (RS) and non-responders (NR) by combining clinical and neuroimaging variables in a repeat-measure functional magnetic resonance imaging (fMRI) investigation. We induced increases in positive and negative affect using visual stimuli under fMRI conditions in 21 MDD subjects and 18 healthy controls (HC). Based on previous neuroimaging investigations and preclinical animal data, we hypothesized that increased activation of the amygdala and the pregenual cingulate during negative affect induction (NAI), and decreased activity of the ventral striatum during positive affect induction (PAI), would differentiate ultimate NR from RS. Following the first scan, treatment with fluoxetine and olanzapine was initiated in the MDD group, with follow-up scans at one- and six-weeks thereafter. We hypothesized that decreases in depressive symptoms would be associated with decreased activation of the ventromedial prefrontal cortex (PFC) and amygdala during NAI and increased activation of the hippocampus during PAI. Eleven MDD subjects met criteria for clinical remission at study endpoint. Based on trait differences between MDD and HC, we hypothesized that differences observed during NAI would be limited to brain regions involved in regulation of the affective state, including the dorsolateral PFC and the anterior midcingulate cortex. The results of the analyses confirmed the a-prior hypotheses and additionally demonstrated differential activation of the insular, medial temporal, and premotor cortex during repeat PAI and NAI between HC, RS, and NR. These findings provide: i) a neuroanatomical target of successful antidepressant therapy during PAI/NAI; ii) a differential effect of depressive symptoms and dispositional affect on brain activation during PAI/NAI; and iii) an a-prior method to differentiate RS from NR, and iv) demonstrate the need for additional treatment to prevent relapse in the remitted state.

This dissertation aims to investigate the correlations of visual evoked potentials during the experimental process of serial passive affective priming. The aim of this dissertation is to identify partial processes of affective perception, which are influenced by relations to previous affective priming stimulation. The research is designed as a laboratory EEG experiment, which uses affective priming techniques, particularly its sequential passive multimodal (auditory-visual) variation. The research experimentally manipulates emotional characteristics of stimuli that are constructed on the basis of the dimensional theory. As a starting dimension, arousal was chosen that is equivalent to psychic activation connected to reactions to stimuli. The study was carried out in the PF JČU neurological laboratory using a 64 channel EEG Biosemi Active II. Probands was selected from the JČU students, whose brain electrical activity was measured during an exposure to affective stimuli from international emotional elicitation databases. Records from 29 people were used. The independent variable used was the variation of priming and arousal characteristics of the priming stimulus from the affective melodies database (Eerola &Vuoskoski, 2010) and the arousal characteristics of a visual stimuli (Marchewka et al., 2014). Visual perception is the most explored ERP process, therefore the differences between the results of this dissertation study and comparative studies can be the basis for interpreting the mechanism of contextual affective transmission. Time progress and activation reactions are modulated based on experimental conditions and the dependent variables are the differences of latency and amplitude of individual components of evoked potentials, which represent partial psychological processes. The use of sound as priming stimulus together with a high interstimulus interval decreases the conflict between perceptual processes in selective attention. The differences in processes of visual perception according to affective arousal characteristics of stimuli suggest a parietally increased early posterior negativity (EPN) and late positive potentials (LPP) of high-arousal stimuli in comparison to low-arousal stimuli. Signs of EPN manifest as indicators for prioritization of attention in comparison with actively motivating stimuli. The priming effect manifested in P1 and N1 components occipitoparietally and in N2 centroparietally, which suggest stronger negativity of EPN in the case of previous priming. LPP increase for the priming condition was there only for high-arousal stimuli. The cause for higher activation for priming conditions in P1 and N1 is unknown, it is a case of premature latency for possible explanation using the evaluation mechanism. The results showcase the influence of conflict between processes of attention or the alternative interpretations of affective priming based on the influence of context on the formation of evaluative conclusions. The priming effects in LPP show a lower later parietal activation of primed stimuli which can be connected to their previous increased activation as a part of early and medium latency component.