Shy or sociable : introversion/extraversion and message recall

textPersonality research has long been an area of interest in the study of consumer behavior. Currently, common practice is to segment prospective audiences by demographic variables (age, gender, and race) instead of psychographics (values, attitudes, personality). In this research, the author investigates the relationship between personality type (introversion/extraversion) and message recall. Using 122 undergraduate and graduate students, recall was examined across two forms of stimulus (incongruent and congruent messages). Results indicated that while there is no relationship between personality type and message recall, there is a relationship between the frequency of advertising messaging and recall. Results are discussed individually by messaging frequency and personality type with further suggestions for future research.Advertisin

The Effect of Teacher’s Instructional Language Types on Intrinsic Motivation, Self- Efficacy, and Performance Accuracy in A Darts Throwing Skill

Introduction: Features of the environment where practice takes place may influence performance, learning as well as the quality of experienced motivation. This study was performed with the aim of investigating the effect of teacher’s instructional language on students’ intrinsic motivation, self-efficacy, and performance accuracy while they were involved in performing a darts throwing skill. Methods: Forty-eight female students were randomly divided into three instructional language groups (autonomy supportive, controlling, neutral). All three groups watched the same silent clip about darts throwing. They performed 21 throws (as pre-test) and subsequently, each group watched a specific clip prepared for them. Instructions in the second clip provided learners with different degrees of choice or control in performing the task in spite of similar technical information. Then, each group performed 51 throws as their post-test. On the second day, all groups performed 21 throws without any instruction as retention test. All participants completed the Intrinsic Motivation Inventory by McAuley et al. (1991) before the pre-test and after the post- and retention tests. To test the research results, the statistical procedure ANOVA with repeated measures test with Bonferroni post-hoc test were used (P≤0.05). Results: The results revealed that the instructional language used in the autonomy-supportive group facilitated learning significantly through its effect on intrinsic motivation and self-efficacy (P≤0.05). In addition, on the acquisition and retention tests, the autonomy supportive group showed a significant better accuracy in throwing darts towards targets relative to the other two groups (P≤0.05). Conclusions: Giving choice to learners is a useful way in acquiring motor skills. Teachers must try to provide situations which promote learners’ sense of competence (self-efficacy) which in turn, improves learning. These situations can include information which is effective on the learners’ perception of their abilities. Giving autonomy to learners during practice and changing the instructional language to improve intrinsic motivation are different ways for creating such situations

Decoding cognition from spontaneous neural activity

In human neuroscience, studies of cognition are rarely grounded in non-task-evoked, ‘spontaneous’ neural activity. Indeed, studies of spontaneous activity tend to focus predominantly on intrinsic neural patterns (for example, resting-state networks). Taking a ‘representation-rich’ approach bridges the gap between cognition and resting-state communities: this approach relies on decoding task-related representations from spontaneous neural activity, allowing quantification of the representational content and rich dynamics of such activity. For example, if we know the neural representation of an episodic memory, we can decode its subsequent replay during rest. We argue that such an approach advances cognitive research beyond a focus on immediate task demand and provides insight into the functional relevance of the intrinsic neural pattern (for example, the default mode network). This in turn enables a greater integration between human and animal neuroscience, facilitating experimental testing of theoretical accounts of intrinsic activity, and opening new avenues of research in psychiatry

Bipartite Functional Fractionation within the Default Network Supports Disparate Forms of Internally Oriented Cognition.

Our understanding about the functionality of the brain's default network (DN) has significantly evolved over the past decade. Whereas traditional views define this network based on its suspension/disengagement during task-oriented behavior, contemporary accounts have characterized various situations wherein the DN actively contributes to task performance. However, it is unclear how different task-contexts drive componential regions of the DN to coalesce into a unitary network and fractionate into different subnetworks. Here we report a compendium of evidence that provides answers to these questions. Across multiple analyses, we found a striking dyadic structure within the DN in terms of the profiles of task-triggered fMRI response and effective connectivity, significantly extending beyond previous inferences based on meta-analysis and resting-state activities. In this dichotomy, one subset of DN regions prefers mental activities "interfacing with" perceptible events, while the other subset prefers activities "detached from" perceptible events. While both show a common "aversion" to sensory-motoric activities, their differential preferences manifest a subdivision that sheds light upon the taxonomy of the brain's memory systems. This dichotomy is consistent with proposals of a macroscale gradational structure spanning across the cerebrum. This gradient increases its representational complexity, from primitive sensory-motoric processing, through lexical-semantic representations, to elaborated self-generated thoughts.This research was funded by an MRC programme grant to MALR (MR/R023883/1) and a Sir Henry Wellcome Fellowship (201381/Z/16/Z) to RC

Brain networks in bipolar disorder II: A resting-state fMRI study

Bipolar disorder II (BD-II) is characterized by hypomanic and depressive episodes, accompanied by mild cognitive deficits, which can be postulated to be due to emotional and cognitive dyscontrol, with attention as the binding factor. Structural and functional magnetic resonance imaging (fMRI) have implicated several brain regions across the BD spectrum, including the prefrontal cortex (PFC), cingulate cortex and amygdala. Newer studies also look at whole brain networks using resting-state fMRI (RS-fMRI). A notable RS network is the default-mode network (DMN), typically activated at rest and associated with mind wandering. The aim of the current study was to characterize functional brain networks specifically in BD-II patients (n = 32) by assessing of within and between network connectivity against healthy controls (n = 35) through RS-fMRI (age 18-50). We also assessed the subjects on working memory measures using the RAVLT and BVMT-R. Independent component analysis and dual regression was used for within-network analysis, and FSLNets was used for between-network connectivity and network modeling. Based on earlier findings, we predicted aberrant connectivity within the DMN, increased connectivity within the anterior cingulate cortex, decreased connectivity between the ventrolateral PFC and amygdala, and decreased connectivity between the posterior cingulate cortex and DMN. We also expected visual networks to display increased connectivity to the amygdala. Decreased test performance was observed on the BVMT-R, and decreased delayed recall on the RAVLT. We found no statistically significant changes in connectivity within or between networks, indicating that brain networks in BD-II are not significantly different from healthy individuals. Keywords: rs-fMRI, BD-II, resting-state networks, DMN, PFC, ACC, amygdala, ICA, dual regression, network modeling, within-network connectivity, between-network connectivity, clustering hierarch

Oxygen Polarography in the Awake Macaque: Bridging BOLD fMRI and Electrophysiology

Blood oxygen level dependent (BOLD) fMRI is the predominant method for evaluating human brain activity. This technique identifies brain activity by measuring blood oxygen changes associated with neural activity. Although clearly related, the nature of the relationship between BOLD fMRI identified brain activity and electrophysiologically measured neural activity remains unclear. Direct comparison of BOLD fMRI and electrophysiology has been severely limited by the technical challenges of combining the two techniques. Microelectrode electrophysiology in non-human primates is an excellent model for studying neural activity related to high order brain function similar to that commonly studied with BOLD fMRI in humans, i.e. attention, working memory, engagement. This thesis discusses the development of, validation of, and first results obtained using a new multi-site oxygen polarographic recording system in the awake macaques as a surrogate for BOLD fMRI. Oxygen polarography measures tissue oxygen which is coupled to blood oxygen. This tool offers higher resolution than BOLD fMRI and can be more readily combined with electrophysiology. Using this new tool we evaluated local field potential and oxygen responses to an engaging visual stimulus in two distinct brain systems. In area V3, a key region in the visual system and representative of stimulus driven sensory cortex, we show increased tissue oxygen and local field potential power in response to visual stimulus. In area 23 of the posterior cingulate cortex (PCC), a hub of the default-mode network we show decreased oxygen and local field potential in response to the same stimulus. The default-mode network is a set of brain regions identified in humans whose BOLD fMRI activity is higher at rest than during external engagement, arguing that they sub-serve a function that is engaged as the default-mode in humans. Our results provide new evidence of default-mode network activity in the macaque similar to that seen in humans, provide evidence that the BOLD identified default-mode suppression reflects neural suppression and overall support a strong relationship between neural activity and BOLD fMRI. However, we also note that the LFP responses in both regions show substantial nuances that cannot be seen in the oxygen response and suggest response complexity that is invisible with fMRI. Further the nature of the relationship between LFP and oxygen differs between regions. Our multi-site technique also allows us to evaluate inter-regional interaction of ongoing oxygen fluctuations. Inter-regional correlation of BOLD fMRI fluctuations is commonly used as an index of functional connectivity and has provided new insight into behaviorally relevant aspects of the brains organization and its disruption in disease. Here we demonstrate that we can measure the same inter-regional correlation using oxygen polarography. We utilize the increased resolution of our technique to investigate the frequency structure of the signals driving the correlation and find that inter-regional correlation of oxygen fluctuations appears to depend on a rhythmic mechanism operating at ~0.06 Hz

A hipótese da hiperativação na insónia psicofisiológica: estudo da default-mode network e sua modificação após TCC

Doutoramento em PsicologiaA insónia primária é a perturbação do comportamento de sono mais prevalente quer na população clínica quer na comunidade. Uma das formas mais comuns é a insónia psicofisiológica (IP). A hiperativação neuropsicofisiológica, afetiva, cognitiva e comportamental assim como o condicionamento mal-adaptativo entre estímulos associados ao sono e à cama com estímulos indutores de ativação são duas das características mais diferenciadoras desta patologia. Tendo por base a importância que esta perturbação assume em termos de saúde pública, levou-se a cabo 4 estudos empíricos com recurso a ressonância magnética funcional: No primeiro estudo comparou-se a ativação neurobiológica entre um grupo de doentes com IP (n=5) e um grupo de indivíduos saudáveis (n=5) emparelhado quanto ao sexo e à idade quando eram confrontados com palavras que remetiam para preocupações do passado/presente, preocupações do futuro e palavras neutras; no segundo estudo, explorou-se as diferenças na ativação referente à default-mode network (DMN) e outras resting-states nos mesmos grupos do estudo 1; no terceiro e quarto estudos, repetiram-se os mesmos procedimentos para um grupo clínico (N=2) após estes terem sido submetidos a terapia cognitivo-comportamental para a insónia (TCC-I). No geral, verificou-se que os doentes com IP exibiram um padrão generalizado de hiperativação em áreas associadas à DMN quer quando confrontados com estímulos ativadores quer em repouso; em termos de ativação nas resting-states, constatou-se que, em repouso, o grupo clínico apresentou disfunções significativas. Após TCC-I, observou-se que os indicadores disfuncionais verificados nos estudos anteriores se esbateram tendendo a aproximar-se do perfil de ativação dos indivíduos saudáveis. Os resultados obtidos reforçam assim a ideia da hiperativação na insónia ao longo das 24 horas do dia assim como do papel fundamental que a ativação cognitiva parece ter na etiopatogenia e no tratamento da insónia. Para além disso, este trabalho contribui para um melhor entendimento da neurobiologia da insónia e sugere que se podem identificar mecanismos neuronais subjacentes às modificações operadas pela TCC-I.Primary Insomnia is the more prevalent sleep disorder both in clinical and community samples. One of the most frequent subtypes is psychophysiological insomnia (PI). The hyperarousal at different levels – biological, affective, cognitive, and behavioral – and the maladaptive conditioning between sleep-related stimuli and arousal are two major features of PI. Since this is a disorder which assumes an important role in public health, we performed 4 empirical studies recurring to fMRI: In the first study, we compared neurobiological activation between a group of PI patients (n=5) and a sex- and age-matched control group (n=5) when they were exposed to words concerning to past/present worries, future worries and neutral words; in the second study, we explored the activity of default-mode network (DMN) and other brain resting-states in the same groups as study 1; in the third and fourth studies, we repeated both experiments in a clinical group of patients with PI (N=2) after they underwent cognitive-behavioral therapy for insomnia (CBT-I). In general, it was observed that PI patients exhibited a generalized pattern of hyperarousal in several brain areas associated with DMN when they were confronted with affective stimuli and when they were resting in the fMRI scanner. In terms of activation of brain resting networks, we observed that the clinical group presented significant dysfunctions. After CBT-I, it was detected that the dysfunctional indicators observed in previous studies normalize, approaching the activation patterns typical of healthy individuals. The obtained results enhance the idea that the hyperarousal in PI is present during the 24-hours of the day; besides, the key role that cognitive arousal may be in the etiology and therapy of insomnia is also highlighted. In conclusion, this work contributes to a better understanding of neurobiology of insomnia and suggests that it might be possible to identify neural mechanisms underlying modifications accounted by CBT-I

Exploring the combined use of electrical and hemodynamic brain activity to investigate brain function

This thesis explored the relationship between electrical and metabolic aspects of brain functioning in health and disease, measured with QEEG and NIRS, in order to evaluate its clinical potential. First the limitations of NIRS were investigated, depicting its susceptibility to different types of motion artefacts and the inability of the CBSI-method to remove them from resting state data. Furthermore, the quality of the NIRS signals was poor in a significant portion of the investigated sample, reducing clinical potential. Different analysis methods were used to explore both EEG and NIRS, and their coupling in an eyes open eyes closed paradigm in healthy participants. It could be reproduced that during eyes closed blocks less HbO2 (p = 0.000), more Hbb (p = 0.008), and more alpha activity (p = 0.000) was present compared to eyes open blocks. Furthermore, dynamic cross correlation analysis reproduced a positive correlation between alpha and Hbb (r: 0.457 and 0.337) and a negative correlation between alpha and HbO2 (r: -0.380 and -0.366) with a delayed hemodynamic response (7 to 8s). This was only possible when removing all questionable and physiological illogical data, suggesting that an 8s hemodynamic delay might not be the golden standard. Also the inability of the cross correlation to take non-linear relationships into account may distort outcomes. Therefore, In chapter 5 non-linear aspects of the relationship were evaluated by introducing the measure of relative cross mutual information. A newly suggested approach and the most valuable contribution of the thesis since it broadens knowledge in the fields of EEG, NIRS and general time series analysis. Data of two stroke patients then showed differences from the healthy group between the coupling of EEG and NIRS. The differences in long range temporal correlations (p= 0.000 for both cases), entropy (p< 0.040 and p =0.000), and relative cross mutual information (p < 0.003 and p < 0.013) provide the proof of principle that these measures may have clinical utility. Even though more research is necessary before widespread clinical use becomes possible