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Completing activities of daily life relies on using both cognitive and physical resources efficiently, but these are affected by age. This may be due either to an age-related reduction in the resources we have available for carrying out tasks or to a reduction in our ability to use these resources efficiently. These resources comprise a set of processes called executive functions (EF), which collectively allow us to plan, initiate and monitor our performance of activities. Control and allocation of these resources is attributed to a central mechanism, sometimes called the central executive or executive attention, but the parameters that determine how resources are allocated are not well understood. Even simple or apparently automatic activities, such as walking, require attention, meaning that when task demands increase, for example when walking and speaking on the phone, there is a loss of efficiency in both tasks. The dual-task (DT) paradigm is an empirical means of examining the way attentional resources are allocated between two tasks by comparing their performance together in relation to how well they are carried out singly. Asking people to perform a cognitive task, such as counting backwards or spelling, while walking provides a reasonably naturalistic way to examine how flexibly older adults can divide their attention between the two tasks. Manipulating the demands of the task, either by increasing the difficulty of the cognitive task or instructing the participants to focus on one task or the other (prioritisation) should illuminate the strategies they use to allocate their available attention between the two tasks ask task demands vary. To explore this hypothesis a cohort of physically and cognitively healthy community-dwelling older adults (mean age = 72.3 years) took part in three studies. In the first experiment, 72 participants completed 8 single and dual-task conditions with varying cognitive load (counting back in 3s and 7s) and attention prioritisation (no prioritisation, prioritising walking and prioritising counting). Instructing the participants to prioritise walking in the DT when counting back in 7s produced the best walking and counting performance and this was predicted their score on a standardised measure of cognitive flexibility. In second part of the study, 68 of the participants were tested 12 months later when there was improvement in both their single and dual-task performances. There was also decline in concurrent walking and counting performance, but only when attention was allocated to walking in preference to the cognitive task. Both the improvements and the decline in performance after the 12-month period were predicted by a standardised test for EF at T1. In the third study a separate group of older adults (73.2 years) was trained to walk rhythmically to music, to further investigate the external manipulation of resource-allocation during concurrent walking and counting. Their performances were compared to 2 control groups who did not receive the same intervention procedures. Overall findings from this doctoral research demonstrate that explicitly manipulating attention-allocation during concurrent walking and cognitive activity improved healthy older adults' walking and counting performance and this was strongly associated with better cognitive flexibility. After 12 months, subtle decline in ability to allocate attention to walking during the DT, when attentional-demands were high, was also predicted by cognitive flexibility in an EF task. Together, these findings illuminated the role of executive attention in a rapidly-changing complex task when the ‘wrong' prioritisation could result in a fall. Observing healthy older adults' cognitive flexibility in allocating attention to walking, when required, revealed that executive attention was key to the future maintenance of their current functional well-being.

Selective attention is a specific area of executive control that declines in older adulthood and may be amenable to cognitive rehabilitation. This study explored background music as an accessible and typically enjoyable tool that may exogenously facilitate attention. Two particular properties of a musical piece – (1) mode (i.e., major, minor, or atonal), and (2) tempo (i.e., stimulative or sedative) – influence affect, arousal, and cognitive function, ultimately enhancing or hindering cognitive performance on attention-demanding tasks. Six musical pieces were selected to represent different combinations of mode and tempo. Older adults (i.e., 65-80 years-old; n=16) were recruited from Victoria, BC. Participants completed the Multi-Source Interference Task (MSIT) assessing selective attention at baseline and under the six counterbalanced musical conditions. In each condition, participants reported motivation and task-difficulty, as well as affect and arousal on the Activation-Deactivation Checklist (AD ACL). Musical affect impacted reaction times on MSIT control and interference trials for the first block, but had no influence during the last block. Musical arousal did not significantly impact attention. AD ACL responses, as well as task-difficulty and motivation to succeed on the task did not vary as a function of the music. The results illuminate older adults’ allocation of executive resources between competing goals of regulating musical affect and succeeding on an attention task. Implications are discussed for selecting music specifically to facilitate older adults’ attention in everyday life. / Graduate / 2017-09-22

執行功能指代一系列高水平的認知加工過程。情緒狀態被證明對執行功能具有重要影響。然而，以往研究大多關注消極情緒的影響效應。本研究則借助實驗操作（研究1）和行為問卷（研究2），以國內青少年為被試，考察並比較了不同動機強度的積極情緒如何作用執行功能。此外，執行功能、積極情緒作為獨立的兩個變量，均被證明能夠有效預測青少年的問題行為與社交技能，但是以往鮮有研究探討它們對於這些結果變量的共同預測效力，據此，研究2還對這一問題作了分析。 / 研究1包括兩個實驗，分別考察有/無動機傾向（實驗1）與高/低動機強度的積極情緒（實驗2）對執行功能的影響效應。兩個實驗均為隨機對照設計，並用數字字母任務、Go/No-go任務、Flanker任務、線索回憶任務、N-back任務來測量基本的執行功能，包括定勢轉換、抑制能力、工作記憶刷新。實驗1隨機向每個被試呈現具有不同情感色彩的視頻短片，以此誘發：中性狀態、有動機傾向的積極情緒（興趣）、無動機傾向的積極情緒（逗樂、寧靜）以及動機強度不同的兩種消極情緒（緊張、厭惡）。實驗2則誘發中性狀態以及高/低動機強度的興趣。兩個實驗均測量了情緒誘發前後被試的生理喚醒作為控制變量。研究2用問卷評估了執行功能、不同動機強度的積極情緒、外向/內向的問題行為、五種基本的社交技能，並用回歸模型分析變量間的關係。 / 研究1結果顯示在控制了生理喚醒的效應后：（1）興趣仍顯著損害了所有執行任務表現，興趣動機強度越高，損害越傾向於嚴重；（2）相比中性狀態，逗樂與寧靜均未對執行任務表現造成顯著影響；（3）厭惡較之緊張，前者傾向於更嚴重地損害執行任務表現。研究2的重要結果有，在控制了性別、年齡與大五人格特質的效應后：（1）不論動機強度如何，積極情緒越多就傾向於導致執行功能越差；（2）執行功能在積極情緒與結果變量之間發揮中介作用。可見，動機強度調節著情緒對執行功能的影響效應。研究結果的理論及實踐啓發將在論文中作討論。 / Executive functions (EFs),an umbrella term encompassing various high-level cognitive processes, play an important role in child and adolescent development. Extensive evidence indicates that emotions exert great impact on EFs. However, previous studies mostly concerned the effects of negative emotions on EFs. The primary purpose of this study was to add to the literature by examininghow EFs were influenced by positive emotions that varied in motivational intensity among Chinese adolescents, using an experiment (Study 1) and through behavioral means (Study 2). Given that EFs and positive emotions have been separately proven as strong predictors to problem behaviors and social skills, Study 2 also explored their joint effect in predicting these outcome variables. / Study 1 comprised two experiments, which respectively compared the effects of motivating versus non-motivating positive emotions (Experiment 1 ) and of high-versus low-motivating positive emotions (Experiment 2). Both experiments employed the randomized controlled design and utilized the Number-Letter task, the Go/No-go task, the Flanker task, the Cued Recall task, and the N-back task to assess the fundamental EFs, i.e., set shifting, inhibition-related functioning, and working memory updating. Experiment 1 used film clips to induce hilarity, serenity, interest, anxiety, disgust, and neutral state. Whereas hilarity and serenity are non-motivating positive emotions, interest is the typical motivating positive emotion. Disgust has higher motivational intensity than anxiety. In Experiment 2, three emotional states were induced: low-motivating interest, high-motivating interest, and neutral state. Participants’ physiological arousal (i.e., blood pressure and pulse rate) were measured both before and after the emotion induction in two experiments, in order to control the potential influence of physiological arousal on executive performance. / In Study 2, behavioral measures were used to assess motivating/non-motivating positive emotions, EFs, externalizing/internalizing behaviors, and five basic social skills (i.e., social adaptability, social perception, social confidence, social expressiveness, and impression management). Regression analyses were conducted to explore the interrelationship between these constructs. / Results of Study 1 revealed that after controlling for physiological arousal: (1) interest impaired performance in all five executive tasks, with higher motivational intensity tending to aggravate the impairment; (2) hilarity and serenity, as compared with neutral state, did not cause significantly discrepant performance across all five executive tasks; (3) disgust, as compared with anxiety, tended to cause more severely impaired EFs. Results of Study 2 included that after controlling for demographic and personality variables: (1) high degree of motivating/non-motivating positive emotions tended to predict poor EFs; (2) EFs mediated the relationship between motivating/non-motivating positive emotions and behavioral social outcomes. These results confirmed that motivational intensity modulated the influences of emotions on EFs.Emotions high in motivational tendency were more likely to impair EFs. Possible explanation is that such emotions are linked with specific action urges to acquire desired objects, which could impel the individual to focus cognitive resources on the goal-pursuit and thus narrow down the flexibility and complexity of cognitive processing. Practical implications in simultaneously intervening emotionality and EFs to enhance children and adolescents’ behavioral social functioning will be discussed. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zhou, Ya. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 100-113). / Abstracts also in Chinese; appendixes includes Chinese.

This study explores the relationship between music and creativity. Prior research has conflicting results with some finding that music does influence creativity and some reporting no relationship and others finding that music is harmful to creativity. All of these studies, however, have largely focused on the presence vs. absence of music without consideration for the characteristics (i.e., musical key, tempo, etc.) that make up the sound we identify as music and their unique effects on us emotionally, physically, and cognitively. This dissertation contends that different characteristics of music influence different components of creativity (i.e., novelty and usefulness) through their effects on executive functions—working memory and inhibitory control. The hypotheses presented in this dissertation were tested in a 2x2 between-subject lab experiment with two different control groups (i.e., nature sounds and no audio) using 436 undergraduate students. The results provide support for the physiological and affective consequences of musical key and tempo. However, measures of creativity were unrelated with the proposed mediating mechanisms, making any conclusions about the effects of music characteristics on creativity difficult to draw. Reasons for this are discussed. It can be said, however, that it does appear that music is not harmful creativity as reported by previous studies. Directions for future research are also discussed.

Cognitive impairment among older adults with type 2 diabetes may worsen health outcomes via negative impact on compliance with medical self-care recommendations. Results of several previous studies indicate that cognitive deficits are present in older European American adults with type 2 diabetes under some conditions, particularly related to glucose dysregulation (as evidenced by high glycated hemoglobin, i.e., HbA1c). Despite the fact African Americans are disproportionately affected by diabetes and suffer significantly greater numbers of complications and more severe complications relative to European Americans, no published studies have examined cognitive functioning among older African American adults with type 2 diabetes. Further, markers of systemic inflammation have been associated with cognitive impairment in several conditions, but this relationship has not been examined in older adults with type 2 diabetes. The purpose of the present study was to determine whether: 1) cognitive deficits are present in older African American adults with type 2 diabetes, and whether the deficits are related to 2) glucose dysregulation and 3) systemic inflammation. Several cognitive domains, including verbal memory and executive functions, were assessed in 71 African Americans with type 2 diabetes who ranged from 60 to 80 years of age. Exclusionary criteria included dementia, depression, neurological disease, or brain injury. Also measured were HbA1c and two markers of systemic inflammation: C-reactive protein (CRP) and interleukin-6 (IL-6). Results showed that higher HbA1c was significantly associated with poorer performance on several measures of executive function and verbal memory measures that tap executive function. Higher IL-6 was significantly associated with slower motor function and higher semantic fluency. Higher CRP was significantly associated with improved performance on measures of phonemic fluency, psychomotor speed and mental flexibility/working memory, and fine motor dexterity, but only for those with extremely high levels of CRP; when those participants were removed from the analyses, CRP was inversely related to cognitive performance.

Previous research has studied the relationship between bilingualism and cognitive abilities. In some of those studies results have shown that bilinguals perform better than monolinguals in visual Simon tasks (i.e. they are less distracted by the incongruent stimuli). The aim of the current study is to see if a similar effect can be found in Simon tasks using the tactile and auditory sensory modalities. In this study bilingual participants (36 university students) with different proficiency in their second language performed a Simon task employing two intensities of vibration and two different sounds as the relevant stimuli. The results indicated no negative correlation between either bilingual proficiency and Simon effect or daily use of the second language and Simon effect when controlling for working memory. Without controlling for working memory a negative correlation for the tactile condition and a positive correlation for the auditory condition between Simon effect and daily use of the second language was found. It’s concluded that the statistical power of this study suffers from a lack of participants and that if the test was reproduced with more participants with a greater spread in their language abilities a stronger effect might be seen. Also concluded is that more cross-modal studies need to be performed before conclusions about general cognitive effects of bilingualism can be drawn. / Tidigare forskning har studerat sambandet mellan tvåspråkighet och kognitiva förmågor. Vissa av dessa studiers resultat har visat att tvåspråkiga individer presterar bättre än enspråkiga i visuella Simon-uppgifter (dvs. de blir mindre distraherade av inkongruenta stimuli). Syftet med den aktuella studien är att se om man kan hitta en liknande effekt i Simon-uppgifter inom de taktila och auditiva sensoriska modaliteterna. I denna studie fick tvåspråkiga deltagare (36 universitetsstudenter) med olika kunskaper i sitt andraspråk utföra en Simon-uppgift där två intensiteter av vibrationer och två olika ljud används som relevanta stimuli. När resultaten var kontrollerade för arbetsminne så visades ingen negativ korrelation mellan varken tvåspråkig förmåga och Simon effekt eller daglig användning av det andra språket och Simon effekt. Utan att kontrollera för arbetsminne så fanns det en negativ korrelation för den taktila betingelsen och en positiv korrelation för den auditiva betingelsen mellan daglig användning av andra språk och Simon effekt. Slutsatsen dras att den statistiska kraften i denna studie lider av brist på deltagare och att om testet reproduceras med fler deltagare, med en större spridning i språkförmåga, så skulle en starkare effekt kunna ses. Det konkluderas även att fler tvärmodala studier behöver utföras innan slutsatser om generella kognitiva effekter av tvåspråkighet kan dras.

Metamemory is defined as the knowledge about one's memory capabilities and about strategies that can aid memory (Shimamura, 1994). One particularly intriguing type of metamemory judgment is a tip-of-the-tongue experience, which refers to a strong feeling that a target word, though presently not recalled, is known and on the verge of being produced. Older adults report more TOT experiences than young adults. However, there is great variability among older adults in performance on memory and executive function tasks, and it is unknown whether subsets of older adults experience more TOT states. Additionally, the neural correlates of successful retrieval, TOTs, and unsuccessful retrieval in aging have not been studied. In the studies reported here, the relationship between frontal and medial temporal neuropsychological factor scores (see Glisky et al., 1995) and performance on metamemory tasks was examined. Importantly, this was the first study to examine the neural correlates of tip-of-the-tongue experiences in older adults. In an event-related fMRI design, participants viewed famous and novel faces and were asked to respond regarding successful retrieval, unsuccessful retrieval, or tip-of-the-tongue experiences. Results show that, as a group, older adults had activation in the medial prefrontal cortex and anterior cingulate during tip-of-the-tongue states, consistent with similar studies in young adults (Maril et al., 2001; Pannu et al., 2004, Schnyer et al., 2005). Additionally, activations in lateral prefrontal cortex and medial temporal areas during the task varied systematically with frontal and temporal lobe factor scores. These results provide evidence for differences in neural activation between groups of healthy older adults characterized on the basis of neuropsychological performance, and shed light on the neural underpinnings of the tip-of-the-tongue states in aging.

This research explored whether variation in working memory ability helps account for the wide variation in toddlers' language skills and improves predictive models of language outcomes over time. A cohort of typically developing (TD) (n = 55) and late talking children (n = 24) were assessed at two time points. The initial assessment took place at ages 24-30 months and the outcome assessment occurred 18 months later, when the children were aged 41-49 months. The assessment battery included standardised tests of language and visual cognition; assessments representing aspects of Baddeley's model of working memory: phonological short term memory (PSTM), a measure of processing speed, verbal working memory (VWM), visual spatial working memory (VSWM), and a parent report questionnaire of executive functioning (EF). Study 1 explored the associations between these aspects of working memory and concurrent expressive vocabulary at ages 24-30 months and examined group differences in the measures between TD and late talking children. Study 2 explored associations between aspects of working memory and concurrent expressive language in the same cohort at 41-49 months of age. Group differences in the measures between resolved late talkers (RLTs) and TD children were explored. Finally Study 3 explored the ability of the measures used at 24-30 months to predict language outcomes at 41-49 months. These results were considered in relation to the prediction of language outcomes on group and individual levels. Overall the results indicated a strong relationship between early PSTM and early language measures. A novel finding was that PSTM was significantly lower in the late talking and RLT groups compared with the TD groups, even after controlling for group differences in language and phonology at both time points. This confirms previous research that PSTM plays a role in early expressive vocabulary acquisition, and suggests that early PSTM deficits may be a causal factor for some cases of late talking. For the whole group, three working memory variables (VWM, Emotional Control and Shift) measured at 24-30 months added unique variance to predictive models in total language scores at 41-49 months after previously established early predictors (receptive language and parent education) had been entered into the hierarchical regression model (receptive language R²Δ = 59%; parent education R²Δ = 2%; VWM R²Δ = 8%; Emotional Control R²Δ = 1% and Shift R²Δ = 2%). This is another novel finding which supports the concept of working memory playing a unique role in language acquisition between the ages two and four years. Processing speed did not contribute unique variance to regression models predicting language when other working memory measures were included. The A not B task (measuring VSWM) did not correlate with language. There were concerns with construct validity with the EF parent report measure (Behaviour Rating Inventory of Executive Function – Preschool Version), which meant that the results from this assessment were interpreted with caution. In terms of clinical outcomes, 83% of the late talkers resolved their language delays over the 18 month period, but as a group showed a seven-fold increase in being identified for clinical concerns at the outcome assessment than children who were not late talkers. The majority of these concerns were for poor phonology. While early VWM, Shift and Emotional Control added unique variance to outcome total language scores on a group level, they did not improve prediction of individual outcomes in language impairment status at 41-49 months. Early receptive language delay was a more powerful predictor of later language impairment than late talking in this cohort, as these children (n = 9) showed only a 44% rate of resolution.

The purpose of this research was to establish the feasibility of delivering a 6-week long adapted Mindfulness for Academic Success (MAS) program to post-secondary students who were experiencing difficulties with their academic performance. Feasibility was established based on recruitment success (70%), program attendance (70% of participants attending at least four sessions), and homework compliance (70% homework completed). In addition, we hoped to establish the MAS program’s preliminary efficacy in improving executive and academic functioning and reducing mind wandering, inattention, symptoms of ADHD, and psychological distress. Forty participants from Carleton University were randomized to the MAS program (n = 20) or waitlist (WL) condition (n = 20). The overall dropout rate in this study was 38 %. Forty-five percent of the MAS program and 80% of the WL condition participants completed the study. MAS program completers complied with 32% of the overall homework during the five week reporting period and no student completed individually more than 57% of the assigned homework tasks. Accordingly, we did not meet the session attendance or homework completion feasibility requirements. Our preliminary efficacy results indicated significant improvements in some program outcomes in the intent-to-treat sample and results were more robust for MAS completers. Specifically executive functioning—self-management to time, self-organization, self monitoring, self-regulation of emotions, and executive function (EF) related ADHD symptoms—improved and ADHD symptoms decreased in the intent-to-treat sample and results were more robust in the completer sample. Psychological distress symptoms (depression and stress) and mind wandering decreased only in MAS program completers, but no changes were noted in students’ ability to pay attention to presented information during the mind wandering task. Academic functioning as measured by selecting main ideas, the use of study aids, and time management improved in both the intent-to-treat and completer samples. Changes in concentration and information processing were only evident for MAS program completers, however, changes were also noted in academic anxiety, motivation, and the use of test strategies, although effects were small. No changes were observed in participants’ self-restraint (EF), generalized anxiety, attitude toward school, and the use of self-testing in exam preparation. Although efficacy results suggest the MAS program may be beneficial, low program compliance and lack of change in students’ levels of mindfulness compromise the internal validity of this study and make drawing causal conclusions about the program’s efficacy difficult. Furthermore, while program attendance and homework compliance were correlated with some program outcomes, the lack of correlation between formal practices of mindfulness and program outcomes suggest that non-specific factors may have contributed to observed improvement in study outcomes.