No description available.

No description available.

Listening ability is affected by external factors such as background noise and internal factors such as attention-allocation. I varied listening conditions and cognitive load and evaluated auditory word recognition and ratings of listening effort. Additionally, I investigated how individual differences in working memory capacity affected word recognition, recall, listening effort, and how working memory capacity interacted with other factors. Rönnberg et al.’s (2013) Ease of Language Understanding (ELU) model states that individual differences in working memory capacity will lead to differences in language comprehension in challenging listening conditions, where those with higher working memory capacity will be better at speech recognition. Using a dual-task experiment, participants heard and repeated words presented in three listening conditions: masked with pink noise, masked with babble, and processed through a hearing loss simulator. To manipulate cognitive load, participants completed the speech recognition task in both single- and dual-task paradigms. In the dual-task paradigm, participants continuously tracked a pseudo-randomly moving target on a screen for half the experiment. Participants reported perceived listening effort for each combination of listening condition and tracking condition. Additionally, memory for correctly heard words was tested with a recognition memory test. Word recognition performance and listening effort rating data agreed with my hypotheses that difficult listening conditions would produce poorer word recognition performance and increased listening effort. Interesting effects of cognitive load are discussed. The relation between working memory capacity and performance on various measures is also discussed in the context of the ELU model and theories of working memory capacity. Internal and external factors clearly interact to affect listening, and this interaction varies across individuals. / Thesis / Master of Science (MSc) / The ability to hear is affected by many factors, including attention and memory. The goal of this research is to investigate the cognitive factors (attention and memory) that affect hearing and how these effects differ on an individual level. My findings contribute to a better understanding of how background noise and mental demand affect hearing ability and listening effort, as well as how individual differences in cognitive ability further influence these factors. Results suggest that background noise and increased mental demand will decrease listening ability and increase listening effort. These changes in listening differ according to individual cognitive ability.

The majority of memory research, and research on its cognitive underpinnings has thus far focused on retrospective memory, or memory for things learned or rehearsed in the past. More recently, however, prospective memory, or the memory for future intentions, has become a major area of research. It is theorized that prospective and retrospective memory may both rely on similar constituent parts such as working memory and selective attention; the relationship between these constructs and prospective memory is, however, significantly less clear than for retrospective memory. In this study we sought to further clarify the role that cognitive process play in prospective memory performance using an SEM approach that included monitoring as a mediating variable in addition to focal, non-focal, and time-based prospective memory task condition. Results suggest a monitoring component is important in both focal and non-focal conditions, and that the type of monitoring observed in this study is related primarily to proactive interference, and reflects participants’ ability to disengage from no longer relevant stimuli¬¬¬.

Recent research has implicated working memory in unconscious tasks, controversially shifting the viewpoint of conscious access necessitating working memory functions (Soto, Mäntylä & Silvanto, 2011). The aim of this study was to investigate the flexibility of unconscious working memory using continuous flash suppression (CFS). Participants (n=18) completed a simple delayed-match-to-sample (DMS) task. Two conditions required the matching of either objects or spatial locations. CFS was used to render stimuli invisible and the perceptual awareness scale (PAS) helped to determine subjective conscious experience. Analysis determined no significant findings in d’ or reaction times. This confirmed the null hypothesis, that there would not be an affect on working memory due to presentation of visually suppressed information. These results may have been due to a lack of effect, complexity or procedural issues. Further research is needed to elucidate these non-significant results. This is especially critical since alternative methods examining unconscious working memory have found significant results.

This paper investigates the influence of readers' linguistic proficiency level and working memory functions on the reading behaviors and processes of readers of Arabic as a foreign language (henceforth RAFL). Two aspects of reading comprehension, speed and accuracy, are examined in light of readers' word decoding efficiency, recall performances, response times, scores, and readers' responses to two quantitative tests: a questionnaire and an interview. Twenty-four subjects participated in this study and were divided into two subgroups based on their proficiency level. The proficiency of these subjects was determined based on their academic level and their overall GPA in Arabic. All subjects completed a series of reading passages, in two separate sessions, followed by comprehension questions. Reading and answer time on the reading passages and questions were timed and scored. Data was also collected retrospectively using a questionnaire and an interview. The results suggest that reading comprehension and the ability to select and implement specific reading processes are impacted by the proficiency level of subjects as well as their word decoding skills. A strong correlation between comprehension outcomes and working memory functions was also found. That is, working memory capacity was found to be influential on the reading behaviors of readers especially at the sentence level with better performances reported for readers with larger and more elaborate vocabulary repertoire. Based on these results, some implications and conclusions are discussed for both Arabic reading research and foreign language classroom.

As life expectancy increases in modern societies, a greater importance has recently started to be given to cognitive aging. Alzheimer's disease (AD) affects the memory capability of individuals at advanced ages, independently of their general physical health. However, AD is suggested to have an undetectable development many years prior the first clear behavioral symptoms. This silent presence of AD may allow scientists to detect its initial stages, at which a combination of prevention treatments, such as medication and cognitive training, can be more effective. This study extends a line of research that aims to identify possible 'silent' biomarkers of AD using working memory performance and electrophysiological recordings (EEG) in healthy adults. Working memory (aka., short-term memory) is a memory sub-type used in everyday life that allows us to execute tasks in short periods of time. Given the significant parallels of working memory with other forms of long-term memory and its clear facility to be employed in experimental settings of short duration, working memory is a suitable candidate to identify early biomarkers of memory deficits ingeneral. In this study we assessed the cognitive performance and the electrophysiological response - via EEG signals - in a visual working memory recognition task that included the interference of past memories over the present ones. This 'proactive interference' effect is evaluated has a possible biomarker candidate for AD. Our findings reveal that subjects take longer reaction times in the recognition of visual items in the proactive interference condition in comparison to no interference. Additionally, we report an early (170-180 ms) and a later (430-450 ms) EEG components (ERP) that underlies the neural processing responsible for the resolution of this working memory interference. These two time intervals are interpreted as revealing the resolution of proactive interference at two difference stages of visual information processing ('letters'): the phonological (sub-lexical) and semantic (lexical) levels respectively. / --

<p>Higher-order cognitive functions, such as executive function (EF) and intelligence, are crucial to the everyday functioning of human beings. Gaining knowledge about these functions is important for our general understanding of human nature as well as for our ability to help those who may not develop these processes optimally. The present thesis focused particularly on the EF component working memory (WM), described as the ability to maintain informa-tion in consciousness during short time periods with the purpose of using that information in complex cognition. The major aims of the thesis were to increase our understanding of higher-order cognition in children as well as of deficiencies in intelligence found in children with Attention Deficit Hyperactivity Disorder (ADHD). We approached these aims by studying the interrelations among EF-related components in terms of their independent contributions to intellectual functioning. We also studied whether the lower intelligence in children with ADHD was mediated by fundamental EF-related components or whether these deficiencies went beyond the weaknesses in these specific cognitive functions.</p><p>Interpreting the present data, we suggest that intellectual functioning in children is best viewed as representing a system of primarily independent parts that may be accompanied by an overarching common mechanism. The multiple components involve, but are surely not limited to, WM functions, inhibitory functions, sustained attention, and processing speed. One of these functions, WM, was found to be further partitioned into domain-specific executive WM processes and domain-specific short-term storage processes, all of which constitute important aspects of higher-order cognitive functioning. We have further learned that deficits in fluid intelligence in children with ADHD may entail more than weaknesses in specific central cognitive functions. This additional deficit is cautiously interpreted as involving supe-rior executive attention functions setting the stage for the development and integration of the EF system as well as the “intelligence system”.</p>

In New Zealand, approximately 10% of births are considered premature, that is less than 37 weeks gestation. With advances in medical technology, young infants are surviving gestation periods as few as 23 weeks. It is expected that many of these severely premature infants will demonstrate some problem in their academic, or cognitive function including language functioning. It is agreed that children who are born severely premature often present with language problems, the nature of the difficulties are not clear. Research examining language abilities that involve cognitive functions such as inference generation have demonstrated that children born prematurely exhibit difficulties with phonologic short-term memory and executive function. Language tasks such as inference understanding require children to integrate real-world knowledge with the linguistic information to generate and produce language that is more complex. The aim of this study was to discover if the language of children born severely premature differs from that of language-age matched peers. This study examined high-level language abilities of school-age children born severely prematurely, specifically, language tasks that involved executive functions including working memory, story inferencing, and recognising absurdities. Six children who were born less than 28 weeks gestation participated in this study. Their results on the above measures were compared to a language-aged matched comparison group, determined by performance on a standardised test. It was hypothesised that the children born severely premature would not differ from their language-age matched peers on measures of general language ability but differences would exist on measures of language processing and inferencing. The findings overall showed little difference between the preterm group and their language-age matched peers on measures except for the measure of chronological age. Although no group difference was found for the measure of working memory, a larger variance on this measure was observed in the preterm group.

Orem's Self-Care Deficit Theory was used to inform hypotheses of associations between perceived severity of illness, working memory and self-care among adults (>45 years of age) with Type 2 Diabetes Mellitus (T2DM). Working memory capacity was examined as a foundational capability using Orem's theory. Measures include the modified Diabetes Care Profile section on Health Status Composite (HSC) providing information on severity of illness, the Working Memory Index (WMI) from the Wechsler Adult Intelligence Scale (WAIS-III), the Self-Care Inventory Revised (SCI-R) and hemoglobin A1c. Sixty-seven adults with a mean age of 62.9 years who were primarily Caucasian (92.5%) were involved. There were 30 men and 37 women. Mean body mass index was 35.11 reflecting the majority of participants were obese. Findings indicate that HSC is significantly associated with WMI (r = .54, p < .01) and associated with both indicators of self-care, the SCI-R and HgA1c (r = .23, p<.05, r = -.37, p < .01). Working memory was examined as a mediator between severity of illness and the indicators of self-care (SCI-R and HgA1c) with no evidence for mediation. Findings are discussed in relationship to Orem's Theory of Self-Care Deficit.