The present study investigated the claim that positive mood broadens the scope of attention to include irrelevant information, and if so, whether this loosening of attentional control has longer term cognitive consequences. In Experiment 1, participants in an induced happy mood were more influenced by distracting information that interfered with responses in the global-local task, particularly when this information was global in nature. Experiment 2 demonstrated that, when previously irrelevant information became solutions on a subsequent task, implicit memory for this distraction was positively correlated with naturally-occurring positive mood. This study corroborates findings that individuals in a happy mood are more affected by distracting irrelevant information. Furthermore, this widened scope of attention can facilitate performance on a subsequent task, a finding with implications for the relationship between positive mood and creativity.

The present study investigated the claim that positive mood broadens the scope of attention to include irrelevant information, and if so, whether this loosening of attentional control has longer term cognitive consequences. In Experiment 1, participants in an induced happy mood were more influenced by distracting information that interfered with responses in the global-local task, particularly when this information was global in nature. Experiment 2 demonstrated that, when previously irrelevant information became solutions on a subsequent task, implicit memory for this distraction was positively correlated with naturally-occurring positive mood. This study corroborates findings that individuals in a happy mood are more affected by distracting irrelevant information. Furthermore, this widened scope of attention can facilitate performance on a subsequent task, a finding with implications for the relationship between positive mood and creativity.

The purpose of this study was to examine whether infants' social attention, as well as their joint attention behaviors uniquely predicted emerging language abilities. This longitudinal study examined attention regulation skills, joint attention behaviors, infants' expressive/receptive language (current), emerging communication abilities at 16- and 17-month-old (time 1); expressive/receptive language (subsequent) at 18- 19-month-old (time 2). Infants' sustained attention was measured by their attention control to a central stimulus in the presence of a distracter competing for their attention. Dynamic human face (upright, inverted) and abstract display with their matched voice tracks were used to separately measure infants' attention regulation to different types of events. Infants' sustained attention was estimated by their latencies away from central stimuli to distracters, as well as their fixation duration and gaze count on central events and distracters. It was found that infants' latency away from the abstract figure toward the distracter was the only variable that significantly negatively predicted current expressive vocabulary. Initiating joint attention was observed to significantly predict infants' abilities in current receptive vocabulary. The emerging language communication ability predicted expressive vocabulary at two times. In addition, infants' fixation and count to the upright speaker's face and eyes contributed significant amount of variance in initiating joint attestation. The fixation and gaze count on the distracter in the upright condition significantly predicted infants' emerging language skills. / Ph. D.

Navigation through the environment requires the ability to select relevant information from a multitude of irrelevant stimuli. Under conditions of processing conflict, attention and cognitive control processes bias sensory input based on internal goals. These processes are supported by the interplay of a fronto-parietal attention network that exerts a top-down influence on information processing and a superior temporal network that operates in parallel and that responds in a stimulus-driven manner to behaviorally salient stimuli. It is often reported that nicotine can enhance top-down attention control and reduce distraction. In experiments 1 and 2, the effects of increasing control demands on behavior were assessed using electrophysiological (EEG) and behavioral measures in an auditory number parity decision task with different levels of distraction. Participants made forced choice ‘odd’ or ‘even’ number decisions, while ignoring preceding or simultaneous novel distractors. A group of non-smokers was compared to overnight abstinent smokers (9 hours) and after nicotine intake via 2 mg nicotine tablet or via smoke-inhaled nicotine. The results revealed that preceding distractors impaired task performance due to orienting to and reorienting from the distractor. Simultaneous distractors did not cause orientation of attention (indicated by absence of a P3a Event-Related Potential) and produced smaller increments in response latencies. However, this type of complex novel stimulus initiated processes of memory updating that significantly impaired response sensitivity and accuracy. Nicotine withdrawal enhanced these distraction effects, whereas nicotine intake, particularly via smoking, normalized performance. In experiment 3, dichotic listening performance in a group of non-smokers was compared to abstinent smokers (12 hours) using behavioral, EEG and functional Magnetic Resonance Imaging (fMRI) measures. The perceptual salience of the stimuli was manipulated by systematically varying the Inter-aural Intensity Difference (IID) between them. The analysis pointed to distinct brain networks that differentially activate depending on the level of competition between sensory inputs and these effects were additionally modulated by nicotine withdrawal. Nicotine withdrawal impaired behavioral performance supported by evidence of enhanced use of memory and attention resources, and some evidence of task-independent default mode network activation. Overall, the findings suggest that withdrawal from nicotine, particularly in heavy smokers, is associated with impairments in cognitive control and that subsequent intake of nicotine serves mainly to normalize performance.

Two continuous performance tests were administered to normal adult subjects. The mode of presentation (visual or auditory) and the type of task (vigilance or distractibility) were varied, and their effects on performance measured. Data were collected on eighty-two subjects, and results indicated that auditory presentation of stimuli increased the difficulty of both tasks. Results also suggest that the distractibility task administered in either mode was more difficult than the vigilance task. Intercorrelations among the four continuous performance tasks are provided. Normative data are presented on all four tasks administered. A measure of symptoms of attention-deficit disorder in adults, the Adult Behavior Checklist, was found to correlate significantly with another measure of pathology, the SCL-90-R.

Ce travail porte sur l'attention chez le cheval domestique. Il vise, dans un premier temps, à évaluer les capacités d'attention des chevaux grâce au développement d'outils de mesure. Nous avons ainsi développé deux tests comportementaux permettant d'évaluer respectivement l'attention visuelle (e.g. test d'attention visuelle, VAT) et auditive (e.g. test de diffusion de sons inhabituels, AAT). Les résultats montrent que ces tests comportementaux permettent la mesure de caractéristiques attentionnelles stables au cours du temps et prédictives de l'attention (i.e. VAT) et de la distractibilité (i.e. AAT) du cheval dans d'autres contextes, à savoir lors d'un test d'attention communément utilisé chez d'autres espèces (the ''5-choice serial reaction time task''), mais aussi en contexte non expérimental comme lors du travail (e.g. exercice à la longe, en reprise). Nos résultats montrent, par ailleurs, des variations individuelles d'attention d'ordre qualitatif (structuration et niveau de l'attention) et quantitatif (durée d'attention). Dans un second temps, nous avons examiné certains facteurs de modulation (intrinsèques et extrinsèques) de l'attention du cheval. Les tests développés ont alors été appliqués dans différents sites équestres. Les résultats montrent que l'attention des chevaux est modulée : i) par des facteurs intrinsèques tels que la race, le sexe des individus ou encore leur état de bien-être; et ii) par des facteurs extrinsèques tels que les conditions de vie offertes aux chevaux, le travail et particulièrement la discipline d'équitation. Enfin, nous nous sommes interrogés sur la possibilité de promouvoir l'attention du cheval au travail via des actions humaines spécifiques. Nous avons ainsi montré que l'utilisation d'une récompense alimentaire augmente rapidement l'attention du cheval sur la tâche à réaliser, et en conséquence améliore ses performances d'apprentissage, tandis que de tels effets n'ont pas été obtenus avec une « récompense » tactile. L'ensemble de ce travail permet des avancées méthodologiques novatrices pour appréhender les capacités cognitives du cheval et ses facteurs de variation. Ces résultats permettront de conseiller les utilisateurs de chevaux en termes de choix d'animaux, de gestion des séances de travail et des conditions de vie. / This study investigated attention in domestic horse. It aims, firstly, to evaluate horses’ attentional abilities by developing experimental tests. To this end, we developed behavioural visual attention (VAT) and auditory attention (AAT) tests. The results show that these behavioural tests give accurate measures of horses’ attentional characteristics. These measures are stable over time and can predict an individual’s attention (VAT) and distractibility (AAT) during another attention-testing paradigm frequently used in other species (the ‘5-choice serial reaction time task’) and in a non-experimental context: work (e.g. lunge or riding lessons). Furthermore, our results show qualitative (structure and level of attention) and quantitative (duration of attention) variations of attention between individuals. Secondly, we studied both intrinsic and extrinsic factors modulating attention in horses. The tests developed have been used across several equestrian sites. Horses’ attention appears to be modulated by: i) intrinsic factors such as an individual’s breed, gender or welfare state and ii) by extrinsic factors such as an individual’s living condition, work and especially the riding discipline. We finally investigated the possibility of promoting horses’ attention while working via dedicated human actions. We showed that using food rewards rapidly increases horses’ attention on the task and, as a consequence, improves their learning performances. These effects were not found with tactile ‘reward’. In summary, this work has led to innovative methodological improvements to assess horses’ cognitive abilities and the factors influencing them. These results have useful applications to guide horse-handlers through animal selection, work session management and choosing optimised living conditions.

Working in noisy environments can be detrimental to cognitive performance. In order to perform well people have to find a way to attenuate distraction. This thesis aimed to study the balance between distractibility and task demands in the context of office-related tasks as a means by which to better understand how people in the work environment are influenced by environmental noise. In Report 1, 2 and 3 higher focal-task difficulty was achieved by manipulating the readability of the text that participants were asked to read (i.e. either displaying the text in hard-to-read font or by masking it with static visual noise). The results of Report 1 and Report 2 showed that background speech impaired performance on proofreading and memory for written stories respectively compared to silence, but only when the focaltask difficulty was low, not when it was high. In Report 3 it was shown that background speech, road traffic noise, and aircraft noise impaired performance on text memory compared to silence, but again, only when focal-task difficulty was low. In Report 4 it was tested whether higher cognitive load on the focal task would reduce peripheral processing of a to-be-ignored background story. The results of Report 4 showed that participants in the low-load condition recalled more of the information conveyed in the to-be-ignored background story compared to participants in the high-load condition. It was also investigated whether individual differences in working memory capacity (WMC) would influence participants’ memory for written stories (Report 2) and incidental memory of the to-background story (Report 4) differently depending on task demand. The results showed that individuals scoring high on the WMC-test were less distracted by background speech in the easy-to-read font condition (Report 2), and recalled less of the information in the to-be-ignored background story in the low-cognitive load condition (Report 4) compared to individuals that scored lower on the WMC-test. These relationships were not found in the hard-to-read font condition in Report 2, or in the high-cognitive load condition in Report 4. Taken together, these results indicate that higher focal-task difficulty can shield against the detrimental effect environmental noise on performance on office-related tasks. Moreover, it shows that higher focal-task difficulty can help individuals with low-WMC to reach a level of performance that is similar to that of high-capacity individuals. / Människor som arbetar inom den byggda miljön (t.ex. kontor eller skolor) är ofta exponerade för olika typer av miljöljud (t.ex. bakgrundsprat, vägtrafiks- eller flygplansbuller) som kan ha en negativ inverkan på deras förmåga att prestera på kognitiva uppgifter (t.ex. läs- eller skrivuppgifter). För att kunna prestera behöver de som arbetar inom den byggda miljön hitta ett sätt att minska hur distraherade de blir av bakgrundsbuller när de arbetar med kontorsrelaterade uppgifter (t.ex. korrekturläsning eller minne för text). Syftet med denna avhandling var att studera balansen mellan distraktion och koncentrationskrav på arbetsuppgiften som ett sätt att undersöka vilken inverkan bakgrundsbuller i arbetsmiljön har på människors förmåga att prestera på kontorsrelaterade uppgifter. I Rapport 1, 2 och 3 manipulerades koncentrationskravet på arbetsuppgiften genom att göra texten mer svårläslig (d.v.s. antingen använda ett mer svårläsligt teckensnitt eller genom att maskera texten med ett visuellt brus). Resultaten på Rapport 1 och 2 visade att bakgrundsprat försämrade prestationen på ett korrekturläsningstest och ett textminnestest jämfört med en tyst betingelse, men bara när texten var lättläslig och inte när den var svårläslig. Rapport 3 visade att bakgrundsprat, vägtrafikbuller och flygplansbuller försämrade prestationen på ett textminnestest jämfört med tystnad, men återigen, bara när texten var lättläslig och inte när den var svårläslig. I Rapport 4 undersöktes om ökad kognitiv belastning på en arbetsuppgift skulle minska hur mycket information av ett bakgrundsprat (d.v.s. en berättelse om en fiktiv kultur) som deltagarna kunde återge trots att de blivit instruerade att ignorera det som sades i bakgrunden. Resultatet visade att deltagarna i betingelsen med låg kognitiv belastning kom ihåg mer av informationen från bakgrundsberättelsen jämfört med deltagarna med hög kognitiv belastning. Denna avhandling undersökte också sambandet mellan individuella skillnader i arbetsminneskapacitet och storleken på hur distraherad individen var av bakgrundsprat (Rapport 2), samt sambandet mellan arbetsminneskapacitet och hur mycket individen mindes av det bakgrundsprat de blivit instruerade att ignorera (Rapport 4), och om dessa samband influerades olika beroende på koncentrationskravet på arbetsuppgiften. Resultatet i Rapport 2 visade att individer med hög arbetsminneskapacitet blev mindre distraherade av bakgrundspratet jämfört med individer med låg arbetsminneskapacitet på prosaminnestestet, men bara när texten var lättläslig, inte när den var svårläslig. Rapport 4 visade att i betingelsen med låg kognitiv belastning kom de med hög arbetsminneskapacitet ihåg mindre av bakgrundsberättelsen jämfört med individerna med låg arbetsminneskapacitet, men när den kognitiva belastningen var hög var det ingen skillnad i hur mycket deltagarna kom ihåg av bakgrundsberättelsen mellan individer med hög och låg arbetsminneskapacitet. Sammanfattningsvis visar resultaten att ökat koncentrationskrav på en arbetsuppgift, genom att öka svårighetsgraden (t.ex. genom att använda ett mer svårläsligt teckensnitt), kan skydda mot den negativa inverkan som bakgrundsbuller har på arbetsuppgifter som liknar de människor arbetar med på kontor. Vidare visade resultaten att ökade koncentrationskrav på arbetsuppgiften kan hjälpa individer med låg arbetsminneskapacitet att prestera i paritet med individer med hög arbetsminneskapacitet när arbetsuppgiften utförs i bakgrundsprat.

My objectives are twofold: 1/ investigating the cognitive and electrophysiological mechanisms of response inhibition in healthy or ADHD adults, 2/ providing a training program to reduce impulsivity. According to Braver (2012), action regulation permits to control impulsivity in two ways: proactive inhibition, effected before motive commands and reflected in an event related potential (ERP) in the N2 wave, and reactive inhibition, a rapid correction mechanism interrupting a motor process already well underway, reflected by the P3 wave. / My objectives are twofold: 1/ investigating the cognitive and electrophysiological mechanisms of response inhibition in healthy or ADHD adults, 2/ providing a training program to reduce impulsivity. According to Braver (2012), action regulation permits to control impulsivity in two ways: proactive inhibition, effected before motive commands and reflected in an event related potential (ERP) in the N2 wave, and reactive inhibition, a rapid correction mechanism interrupting a motor process already well underway, reflected by the P3 wave.

L’intolérance au changement est fréquemment observée dans l'autisme et s'exprime dans toutes les modalités sensorielles. L’objectif de ce travail était d’étudier la perception automatique du changement visuel chez des enfants et adultes avec autisme via un paradigme oddball passif. En utilisant l’électrophysiologie, des réponses atypiques aux changements visuels mêmes mineurs, ont été mises en évidence dans l’autisme, quel que soit l'âge, suggérant une hyperdistractibilité des patients. De plus, l’utilisation de l’IRMf a permis de révéler, lors de la présentation d’un changement visuel, une hyperactivation du cortex sensoriel associée à une hyperactivation du cortex cingulaire antérieur, d’autant plus élevée que les patients avaient des traits autistiques marqués. Cette étude suggère donc qu’une hyper-réactivité sensorielle associée à des troubles de l’attention visuelle sélective contribueraient aux troubles de perception du changement et aux difficultés d'adaptation dans l’autisme. / Resistance to change is often reported in autism spectrum disorders (ASD) and may occur in all sensory modalities. The aim of the present work was to investigate automatic visual change detection in children and adults with ASD using a passive oddball paradigm. Whatever the age, electrophysiological results showed atypical responses to, even minor, changes, suggesting an hyper distractibility in the patients. Besides, fMRI results revealed hyperactivation of the sensory cortex associated with hyperactivation of the anterior cingulate cortex in adults with ASD, the latest being correlated with the degree of autistics symptoms. These studies thus suggest that a sensory hyper-reactivity associated with visual selective attention deficits might contribute to atypical change perception and adaptation in ASD.

Attention-deficit/hyperactivity disorder (ADHD) also known as hyperkinetic disorder is a well-recognised neurodevelopmental disorder) that affects approximately 5.9% to 7.1% of children and adolescents. ADHD is one of the most common psychiatric disorders of young people, affecting primary school children. ADHD symptoms are associated with impairment in academic, behavioural, social, and emotional functioning, generally resulting in substantial difficulties in school settings. Specifically, learners with ADHD or those perceived to have it are at significantly higher risk for academic underachievement, grade retention, identification for special education services, and school drop-out. The purpose of the study was to explore grade three teachers’ experiences of learners perceived to have ADHD in Soweto mainstream primary schools with the aim of harvesting intervention strategies (if any) employed in teaching learners perceived to have ADHD. This study employed a qualitative research approach with a case study method employing semi-structured interviews, focus group and an ADHD-specific knowledge and attitudes of teachers (ASKAT) open ended questionnaire section. The findings of this study indicate that lack of training teachers on neurodevelopmental disorders such as ADHD. Further that teacher experience is characterized by feelings over being overwhelmed exacerbated by not know how to support the learners perceived to have ADHD, Stereotyping and labeling the learners; poor time management and general lack of knowledge of ADHD. They however employ various interventions from their day-to-day experience and not necessarily evidence-based intervention that they received. / Psychology of Education / D. Phil (Psychology (Psychology of Education))