Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aging is associated with several changes in human body functions and structures. Neuromuscular, mechanical and cognitive deficits may increase difficulties in locomotion, especially under challenging situations as the gait over obstacles. Such effects can be enforced during situations of dual-task. Limitations for mobility, strength asymmetries and decreased ability of response for changes in the context can affect the gait and increase risks for falling in the elderly. Although physical exercise benefits general health condition, its influence on performance of perturbed gait has been briefly addressed. While the usual gait can be benefited by regular physical exercise, questions still open on how regular exercise contributes to the performance of perturbed gait combined or not with a dual-task, which bring additional cognitive loading to the elderly. The purpose of this study was to evaluate the biomechanics of gait crossing a obstacle while performing or not a dual-task in sedentary and physically active elderly. Elderly aged 60 years old or more participated in the study. They were classified as sedentary or physically active. A brief interview was performed, followed by examination of cognitive status, leg preference and gait kinematics under three conditions: during the usual overground gait, overground gait crossing an obstacle and during overground gait crossing an obstacle while performing a dual-task. Results suggest that some kinematic variables of aged gait are improved in the physical active elderly, even with the execution of a dual-task. Physically active elderly seemed to adopt a more secure pattern of locomotion while crossing over an obstacle, despite of gait asymmetries observed for both the groups. / O envelhecimento acarreta modificações em diversas estruturas e funções corporais. Déficits na capacidade neuromuscular, mecânica e cognitiva podem levar a uma redução na capacidade de locomoção e dificultar a marcha em condições desafiadoras, como na presença de obstáculos. Tais efeitos podem ser aplicados em situações de dupla tarefa. Limitações na mobilidade, assimetrias na força de membros inferiores e menor capacidade de resposta a mudanças no contexto da tarefa podem afetar a marcha e aumentar o risco de quedas em idosos. Embora o exercício físico apresente uma série de benefícios para a qualidade de vida em idosos, sua influência sobre o desempenho na marcha com perturbações tem sido pouco investigada. Enquanto a marcha usual pode ser aprimorada pelo exercício regular, não se sabe como o exercício regular contribui para o desempenho na marcha em diferentes condições de perturbação onde cargas cognitivas adicionais também estão envolvidas. O objetivo deste trabalho foi avaliar a biomecânica da marcha com obstáculo e dupla tarefa em idosas sedentárias e fisicamente ativas. Participaram do estudo mulheres com idade de 60 anos ou mais, que foram classificadas como fisicamente ativas ou sedentárias. Após a realização de uma anamnese, as idosas foram avaliadas quanto ao estado mental, preferência lateral e cinemática da marcha em três situações: durante a marcha normal, livre de obstáculo; durante a transposição de um obstáculo; e durante a transposição de um obstáculo concomitante à realização de uma tarefa cognitiva secundária. Os principais resultados sugerem que algumas variáveis da marcha com obstáculo são beneficiadas pela prática do exercício regular, mesmo com a realização de uma dupla tarefa. Idosas fisicamente ativas parecem assumir padrões mais seguros de marcha para cruzar um obstáculo, ainda que assimetrias ocorram para ambos os grupos.

Vor dem Hintergrund der PSI-Theorie werden Fragen der Vorhersage von Leistung entwickelt. Neben einer kurzen Darstellung der Theorie werden zunächst zur Methodenexploration in 4 Experimenten im Stroop-Paradigma Fragen der Grundlagenforschung zum Stroop-Interferenz-Reduktions-Effekt (SIRE) durch nonverbale emotionale Primes beantwortet. In 3 weiteren Studien konnte gezeigt werden, dass Leistung mit der Interaktion aus Selbststeuerung insbesondere der Komponente Zielumsetzung und dem nichtreaktiven Maß der Stroop-Interferenz nach Leistungsprimes vorhergesagt werden kann. Es scheint Hinweise auf eine gewisse Gesetzmäßigkeit dieser Interaktion zu geben. Bei der Leistungsvorhersage wird eine invers sinusförmig verlaufende Charakteristik der Interaktion vermutet, die in 3 Studentenstichproben zum Problemlösen, zur Klausurleistung sowie zum Fortschritt bei Leistungszielen während eines Semesters untersucht werden konnte. Die wesentlichen Erkenntnisse der Vorhersage aus reaktiven Maßen (Selbststeuerung, insbesondere Willensbahnung) und nichtreaktiven Maßen (Intentionsgedächtnisnutzung) werden dargestellt. Implikationen für die Anwendung gehen in Richtung größerer Studien zur Erforschung dieser prädiktiven Interaktion. Dieses Muster ist relevant für die Anwendungswissenschaften Klinische Psychologie als auch die Arbeitspsychologie i.S. von persönlichkeitsfördernder Gestaltung der Arbeit.

L'objectif de cette thèse a été d'investiguer la question de la généralité et de l'automatisation des processus de contrôle inhibiteur au fil du développement cognitif. Cette question a été approchée par différentes études expérimentales menées chez l'enfant, chez l'adolescent et chez l'adulte. Trois études ont porté sur la généralité des processus de contrôle inhibiteur agissant dans des tâches appartenant à des domaines cognitifs différents. Dans la première, nous avons voulu répondre à deux problématiques liées aux divergences présentes dans la littérature sur le développement du contrôle inhibiteur dans des contextes émotionnels. Le but de cette étude était de déterminer (a) si le contrôle inhibiteur froid (dans des contextes affectivement neutres) et le contrôle inhibiteur chaud (dans des contextes émotionnellement chargés) suivent un pattern développemental identique, particulièrement à l'adolescence et (b) le degré de spécificité de ces deux types de contrôle inhibiteur au fil du développement. Pour cela, nous avons comparé les performances d'enfants de 10 ans, d'adolescents de 13 ans et de jeunes adultes de 21 ans à une tâche de Stroop couleur-mot affectivement neutre et une tâche de Stroop émotionnel. Dans une deuxième étude, nous avons testé auprès d'un groupe d'enfants de 9 ans si les processus inhibiteurs impliqués dans une tâche classique piagétienne de conservation du nombre (i.e., domaine logico-mathématique) étaient identiques ou partiellement identiques à ceux impliqués dans la résolution de la tâche neuropsychologique classique de Stroop couleur-mot (i.e., domaine verbal). Dans une troisième étude, nous avons testé auprès d'un groupe d'enfants de 10 ans et d'un groupe de jeunes adultes de 20 ans la transférabilité des processus inhibiteurs entre une tâche de discrimination de lettres en miroir (dont il a récemment été démontré qu'elle nécessite l'inhibition) et une tâche classique de Stroop couleur-mot, afin de déterminer (a) si la mise en place de mécanismes inhibiteurs impliqués dans la résolution d'un conflit à un niveau perceptif très précoce (la reconnaissance visuelle de symboles) peut faciliter la résolution d'un conflit à un niveau de traitement beaucoup plus tardif (niveau sémantique et moteur), et (b) si l'âge affecte cette transférabilité. Ensuite nous nous sommes intéressés à l'automaticité des processus de contrôle inhibiteur, testant si le contrôle inhibiteur peut fonctionner de manière totalement inconsciente sur des conflits provoqués par deux stimuli subliminaux interférents. Pour cela, nous avons conçu un paradigme d'amorçage composé d'essais dans lesquels un item de Stroop inversé subliminal précédait un item de Stroop visible. Le but de ce paradigme était de vérifier la présence d'un effet d'adaptation de conflit et d'un effet d'amorçage négatif du stimulus subliminal sur le stimulus visible, deux effets rapportés dans les études utilisant des stimuli visibles et suggérant un transfert des processus de contrôle de l'amorce à la cible. Enfin dans une cinquième étude nous avons cherché à savoir si les différences interindividuelles en termes de contrôle inhibiteur découlent en partie des processus prénataux, sur base de l'analyse de la forme sulcale du cortex, considérée comme une caractéristique qualitative de l'anatomie cérébrale déterminée pendant la vie fœtale et stable au cours du développement. En utilisant l'imagerie par résonance magnétique anatomique, nous avons analysé les corrélations entre les performances à une tâche de Stroop couleur-mot et la forme sulcale de deux régions clefs du réseau neuronal du contrôle inhibiteur, le cortex cingulaire antérieur dorsal et le sillon frontal inférieur (qui limite le gyrus frontal inférieur), chez un groupe d'enfants de 10 ans et un groupe d'adultes de 22 ans. En conclusion, cette thèse apporte un nouvel éclairage à la question de la généralité et de l'automatisation des processus d'inhibition exécutive dans une perspective développementale / The objective of this thesis was to investigate the question of the domain-generality of inhibitory control and its automatization throughout development. This question has been approached by various experimental studies in children, adolescents and adults. Three studies have focused on the generality of control processes operating in tasks belonging to different cognitive domains. In the first study, we wanted to answer two questions related to the discrepancies found in the literature on the development of inhibitory control in affectively charged contexts. The aim of this study was to determine (a) whether cool inhibition (control processes in emotionally neutral contexts) and hot inhibition (control processes in emotionally charged contexts) follow the same developmental pattern, and (b) the degree of specificity of these two types of inhibitory control throughout development. We thus compared the performance of 10-year-olds, 13-year-olds and 21-year-olds to an emotionally neutral color-word Stroop task and an emotional Stroop task. In a second study on 9-year-old children, we tested whether the inhibitory processes involved in a classical Piagetian conservation task (i.e., logico-mathematical domain) were identical or partially identical to those involved in the resolution of the classical neuropsychological color-word Stroop task (i.e., verbal domain). In a third study, we tested on a group of 10-year-old children and a group of 20-year-old young adults the transferability of inhibitory processes between a mirror letters discrimination task (that has recently been shown to require inhibition) and a color-word Stroop task, to determine (a) whether the resolution of a conflict at an early perceptual stage of the processing stream (recognition of visual symbols) can facilitate the resolution of a conflict arising at a much later stage (semantic and motor levels), and (b) if age affects this transferability. Then we looked at the automaticity of the inhibition processes by testing whether inhibitory control can operate completely unconsciously on conflicts arising between two subliminal interfering stimuli. To this end, we designed a priming paradigm consisting of trials in which a subliminal reverse Stroop item preceded a visible Stroop item. The aim of this paradigm was to verify the presence of a conflict adaptation effect and a negative priming effect produced by the subliminal items on the visible items. These two effects are commonly reported in studies using visible stimuli and suggest a transfer of control processes from the prime to the probe. Finally, in a fifth study, we investigated whether inter-individual differences in inhibitory control are in part due to prenatal processes, based on the analysis of the sulcal pattern, considered as a qualitative feature of the cerebral anatomy that is determined during fetal life and is stable during development. Using anatomical magnetic resonance imaging, we analyzed the correlations between the performance on a color-word Stroop task and the sulcal pattern of two key regions of the inhibitory control neural network, the dorsal anterior cingulate cortex and the inferior frontal sulcus (which limits the lower frontal gyrus) in a group of 10-year-old children and in a group of 22-year-old adults. In conclusion, this thesis sheds new light on the question of the generality and the automatization of the inhibitory control processes from a developmental perspective.

Individuals who have experienced a traumatic event and develop Post-Traumatic Stress Disorder (PTSD) frequently show deficits in both primarily “cool” and “hot” cognitive executive functions (e.g., traditional & emotional Stroop tasks, respectively) that can be impacted by high affective salience. Given the dimensional nature of psychopathology, questions remain about individuals within the general population who have experienced trauma but do not meet full criteria for PTSD and yet may manifest problems in these areas, especially areas of hot and cool executive functioning (EF). Thus, the current project was designed to assess hot and cool EF in a relatively large sample of individuals from the general population who have experienced trauma and currently demonstrate sub-clinical levels of post-traumatic symptoms. The Stroop task, Emotional Stroop task, and a novel modified Implicit Association Test were utilized to assess EF across a spectrum of individuals with varying traumatic histories and level of post-traumatic symptoms. Results suggest that a greater frequency of trauma experiences was moderately associated with worse performance on both hot and cool executive functioning measures. Specifically, females within the sample evidenced a close relationship between traumatic experiences, post-trauma symptoms, and executive functioning. Clinical and theoretical implications are discussed.

Racial identity can be defined as the personal understanding, both explicitly and implicitly, that one is similar to some people and different from others, according to concepts based around the idea of race. In the US, there has been a lot of research, including on the identity of persons having parents from different races. However, in the UK, there is the view that race is a taboo topic, and this is particularly true in psychology; hence strikingly little such research has been conducted. This situation seems most evident particularly regarding how mixed-race persons develop their racial identity. This thesis begins to redress the imbalance. A literature review on "race (Chapter 1)", is followed by a literature review on "mixed-race (Chapter 2)", with many ideas forwarded in these two chapters then tested in five further qualitative and/or quantitative research chapters. In order, these investigate the salience of race at the explicit level (Chapter 3), then at the implicit level (Chapter 4, regarding black and white persons). Chapters then investigate the mixed-race identity qualitatively first in adults (Chapter 5), and then qualitatively/quantitatively alongside self-esteem measures in adolescents (Chapter 6); before a fifth empirical chapter considers the implicit level again but this time specifically regarding attitudes by and towards mixed-race persons (Chapter 7). Taken together, the five empirical chapters find that the parental races tend to see "race" differently to each other. Regarding specifically mixed-race, we find that mixed-race persons shift in identity first from childhood (a more black identity) to adolescence (white identity), and then back again from adolescence to young adulthood (black identity). We additionally find that mixed-race persons tend to have a less definite sense of identity than their parental races, and that this view of mixed-race is also held by one of the parental groups (the white group). It is hoped that further research will now begin to build on these findings. The final chapter (Chapter 8) offers a start at this, outlining a new theoretical account of the development of a mixed-race identity.

This study examined the utility of the Trail Making Test Quotient (Trails B/ Trails A) in assessing executive functioning relative to that of common tests of executive function such as the Wisconsin Card Sorting Test, Category Test, and the Stroop Test. The purpose of the current study was to investigate the relationship of the Trail Making Test Quotient (Trails B/ Trails A) with other common tests of executive functioning (i.e., Wisconsin Card Sorting Test, Stroop, Category Test) to determine whether these tests are measuring similar domains of functioning or whether Trail Making Test Quotient (Trails B/ Trails A) offers a more pure measure of executive functioning over and beyond that of Trail Making Test B alone or the difference score, Trail Making Test (Trails B- Trails A). A series of partial correlations were conducted involving the Trail Making Test scores (Quotient, Difference, and B [Raw]), and the scores of the executive functioning measures (Wisconsin Card Sorting Test, Category Test, and Stroop), controlling for age, education, and gender. Trails Quotient, Trails B Raw, and Trails Difference were found to significantly negatively correlate with WCST Total # of Categories. Only Trails B Raw and Trails Difference were found to significantly positively correlate with WCST Perseverative Responses and Category Error. None of the Trail Making Test measures used in this study were found to significantly correlate Stroop Interference. Correlation coefficients were compared to determine the strength of Trails Quotient's relationship with the aforementioned executive functioning measures relative to that of Trails Difference and Trails B Raw. Contrary to the hypotheses of the current study, the Trails Quotient demonstrated a significantly weaker correlation with WCST Total # of Categories, WCST Perseverative Responses, and Category Error than that of Trails Difference and Trails B Raw. Additionally, there were no significant differences in the correlation coefficients of Trails Quotient, Trails Difference, and Trails B Raw with Stroop Interference. However, upon further investigation using exploratory factor analyses, it was discovered that Trails Quotient may have represented a particular component of executive functioning more so than the Trails Difference and Trails B Raw. The results suggest that Trails Quotient offers a unique estimate of executive skill specific to cognitive organization, whereas Trails B Raw and Trails Difference represent multiple executive domains including regulatory and organizational abilities. Clinical practice will benefit from the current study's findings in that assessment of complex executive functioning will be more precise. Future research is needed to determine the utility of the Trails Quotient in identifying specific types and locations of brain injury. Assessment of specific impaired frontal skills common to degenerative dementias and traumatic brain injury may be possible with the use of Trails Quotient contingent upon further research. Future research into the domains of executive functioning and the Trail Making Test should focus on specific skills within regulatory and organizational components, and the development of normative data for Trails Quotient.

Social anxiety disorder is the third most common mental disorder with the lifetime prevalence rate of 13.3% in the US population. Typically, it causes significant impairment in a wide range of functioning and follows a chronic, unremitting course if untreated. Over the past two decades, there has been a dramatic increase in clinical research aimed at examining underlying mechanisms maintaining social anxiety. One line of research has investigated attentional biases in social anxiety, using various cognitive experiment paradigms, including the emotional Stroop and the modified dotprobe tasks. However, overall findings are equivocal about the nature of attentional biases in social anxiety and several methodological problems limit the interpretability of the data. The present study examined attentional biases associated with social anxiety using a new research paradigm in the field of anxiety disorders: the inattentional blindness paradigm. This paradigm presents a social cue in the absence of the subjects’ expectation while they are engaged in a cognitively demanding task, thereby enabling the more purely attentional aspect of information processing to be examined reducing the influence of potential response biases or effortful strategies. Two independent experiments were conducted using nonclinical student samples consisting of individuals high in social anxiety (HSAs) versus individuals low in social anxiety (LSAs) based on the static and sustained inattentional blindness tasks. Overall, results revealed that HSAs were more likely to detect or identify a socially-threatening cue, relative to LSAs; whereas LSAs were more likely to detect or identify a non-threatening social cue, relative to HSAs. These findings were observed only in the presence of a bogus-speech manipulation. These data suggest the promising utility of the inattentional blindness paradigm in investigating attentional biases in social anxiety and perhaps other psychopathological conditions. Theoretical and clinical implications are discussed. / text

One means by which inhibitory control in selective attention may be studied is with the negative priming (NP) procedure. It is widely assumed that children are characterised by reduced capacity for inhibition (Diamond, 2002) and that inhibitory dysfunction is a key characteristic of children and adolescents with ADHD (Barkley, 1997). This should translate into reduced NP effects for these populations. In this dissertation, four studies using the NP procedure find no evidence for reduced inhibitory function in typical children or in adolescents with ADHD. Study 1 examined the magnitude of NP in children compared with adults. An important line of support for the idea that children suffer an inhibitory decrement has been based an empirical report suggesting that conceptual (identity or semantic) NP effects, assumed to reflect the by-product of distractor inhibition, while consistently found in adults are lacking in children (Tipper, Bourque, Anderson, & Brehaut, 1989). In Study 1, the opposite result was found. Study 2 compared NP effects between 7-year-old children and adults while replicating the respective methodologies of the only two studies to explore conceptual NP effects in developmental populations to date (Pritchard & Neumann, 2004, vs. Tipper et al., 1989) to determine the nature of the divergent results between these studies. In Study 2, it was found that distractor inhibition effects are comparable between children and adults when a NP task contains trials in which the distractor stimulus is consistently incongruent with the target stimulus, but that children may be more susceptible than adults to divide attention between target and distractor when a NP task contains a number of trials in which target selection difficulty is reduced. These are critical new findings, highlighting that reduced NP may often relate to methodological artifacts, and when considered in the light of current theories of NP, are also problematic for anti-inhibitory accounts of NP. Having distinguished more definitively the role of inhibition in developmental NP effects, Studies 3 and 4 explored whether the inhibitory process underpinning NP was implicated in young persons with ADHD. To date, evidence for NP in ADHD populations is equivocal. Study 3 found no evidence for a reduced NP effect in ADHD devoid of a corresponding diagnosis. Study 4 found that conduct and oppositional defiant disorders had the potential to confound the evaluation of NP in ADHD. Taken together, results in Studies 1 - 4 parallel very recent results in the literature on NP in older adults and adult psychopathology where presumed reductions of NP in these populations may also be accounted for by methodological artifacts (Buchner & Mayr, in press). It is concluded that NP may reflect a primitive and robust form of inhibitory processing, one that develops early and one that is often the last to deteriorate.

Classical Stroop stimuli and newly developed face/word Stroop analog stimuli were used to investigate hemispheric interactions in Stroop interference effects (SEs) and corresponding event-related potentials (ERPs). Lateralized stimuli were presented unilaterally and bilaterally as congruent or incongruent color strip-word or face-word pairs (to invoke right hemisphere (RH) and left hemisphere (LH) specialization, respectively, in the latter case). The common finding for such tasks is that responses for the congruent condition are faster and more accurate than for the incongruent condition (i.e., the SE). A primary prediction is that the SE will be maximized when both the distractor and target components, or distractor alone, are presented to the specialized hemisphere (i.e., LH for words and RH for faces). A total of 88 right-handed University of North Texas students participated in one of four experiments. Participants manually responded to one component of the stimuli (i.e., color, face, or word), while ignoring the other. Behaviorally, participants showed a robust SE across all experiments, especially for the face/word task with word targets. Findings from the face/word Stroop analog tasks also indicated that SEs were produced by selective attention to either faces or words, implicating a role for top-down (controlled) processes. Hemispheric asymmetries were observed only for bilateral presentations of the face/word Stroop analog stimuli and did not differ for word versus face targets. The results suggest that the LH is less susceptible to interference from the RH than vice versa. Electrophysiologically, anterior N1 and P1, posterior P1 and N1, N2, and P3 components were identified. A SE was found for P3 amplitudes, but not latencies, across all four experiments such that the congruent condition generated greater amplitudes than the incongruent condition, suggesting that the P3 is an index of task difficulty. Surprisingly, SEs were also observed for the early ERP components, albeit embedded in higher order interactions. Taken together, the ERP evidence suggests that there is no single locus of the SE, and instead, the SE appears to be distributed over several stages of information processing.

The Stroop Color coding and word test (Stroop, 1935) is a well-known phenomenon investigating cognitive inhibition, cognitive speed, attention and cognitive flexibility. The Stroop effect refers when processing a stimulus while being exposed to another stimuli simultaneous interfering with the first (Scarpina & Tagini, 2017). This study focuses on a performance part of the Stroop color coding and word test and its relation to personality traits in the HEAXCO-PR using the Mini-IPIP6 (Ashton & Lee, 2007; Sibely, 2012). An experiment was conducted with the control group ( N = 30 ) solving a Stroop color coding and word test and the experiment group ( N = 30) being exposed to two stimuli (audio and visual) with purpose to induce stress. The result of an independent t-test indicated that you can manipulate the result of a Stroop test measuring two outcome variables (Time and Error). One-way MANCOVA was performed with the personality traits used as covariates. The analysis indicated that Extraversion had a significant small impact on Time (F (1,52) = 6.872, p = .011 η2 = .117) ) and Openness had an effect on Error (F (1,52) = 3.167, p = .008 η2 = .057). Openness showed a significant effect on error rate in the performance. Extraversion showed significant effect as a covariate on the completion time of the test. Time and Error showed a significant correlation. To establish the relationship between cognitive inhibition and personality more research is required. More research is also required for the result of this theoretical study to potentially become applicable.