Executive Processes Underpin the Bilingual Advantage on Phonemic Fluency: Evidence from Analyses of Switching and Clustering

Bilinguals often show a disadvantage in lexical access on verbal fluency tasks wherein the criteria require the production of words from semantic categories. However, the pattern is more heterogeneous for letter (phonemic) fluency wherein the task is to produce words beginning with a given letter. Here, bilinguals often outperform monolinguals. One explanation for this is that phonemic fluency, as compared with semantic fluency, is more greatly underpinned by executive processes and that bilinguals exhibit better performance on phonemic fluency due to better executive functions. In this study, we re-analyzed phonemic fluency data from the Betula study, scoring outputs according to two measures that purportedly reflect executive processes: clustering and switching. Consistent with the notion that bilinguals have superior executive processes and that these can be used to offset a bilingual disadvantage in verbal fluency, bilinguals (35-65 years at baseline) demonstrated greater switching and clustering throughout the 15-year study period

Auditory attentional capture : dissociations between objective and subjective indices

With relevance to auditory alarm design, we examined whether the semanticity of spoken words (Negatively-valenced vs Neutral; Non-words vs words; Action vs non-Action words) and their intonation-style ("urgent" vs. "calm") modulate the extent to which words capture attention from a visually-presented serial recall task (objective measure) and whether these behavioural effects map onto subjective ratings of "Perceived urgency" and "Attention grabbingness" (subjective measure). Compared to quiet or a repeated tone, the infrequent presentation of a spoken word captured attention-as indexed by an impairment of serial recall-but there were no effects of semanticity or intonation. However, action words were rated as more urgent and attention-grabbing than neutral words which were rated as more urgent and attention-grabbing than non-words. "Urgent" words were also rated higher in urgency and attention grabbingness than "calm" words regardless of valence. The results question the utility of subjective ratings for the purpose of spoken-alarm design.Godkänd; 2008; 20081008 (jeskor)</p

Effekter av arbetsplatsens auditiva varningssignaler på kognitiv prestation och subjektiv upplevelse

Godkänd; 2007; 20080604 (andbra)</p

The role of semantic content of spoken words and the effect on serial recall

With relevance to auditory alarm design, the aim with this study was to investigate if semantic content of words (Negative, Neutral, Non-words and Action words) and the way words are spoken ("urgent" and "calm") interrupt performance in serial recall when applying a deviant paradigm. Subjective ratings of perceived "Urgency" and "Attention grabbing" were also measured. An interruption in recall was found caused by the words, but no effects were related to the semantic content or to the way they were spoken. Interestingly, results showed that participants rated action words as more urgent and attention grabbing than neutral words and non-words. However, neutral words generated higher ratings than the non-words. Participants also experienced higher urgency and attention grabbing effect by words that were spoken "urgent" than those spoken "calm", independent of whether they were negative or neutral. In conclusion it is argued there is a dissociation between subjective and objective measurements.Godkänd; 2008; Bibliografisk uppgift: Det semantiska innehållets roll för talade ord och dess effekt på seriell återgivning; 20081008 (jeskor)</p

Psychological responses to noise and vibration

Vehicle drivers are a group of workers that are exposed to noise and whole-body vibration (WBV) several hours a day. Some drivers may also be exposed to high mental loads – monitoring and manipulating physical controls while engaging problem solving activities often with strong short-term memory and spatial manipulation components. Present standards and regulations that govern health risk assessment do not take into consideration the complexities of these multiple exposure environments. The effect of one factor (for example, noise or WBV) may be different than the effect of two factors presented together. This thesis investigates whether the combination of noise and WBV affects the performance of cognitive tasks more than when the exposures are presented separately. A series of studies were designed to expose subjects to noise and WBV stimuli designed to simulate real life working conditions. Different combinations of subjective ratings, cognitive tests, and cortisol measurements were conducted both during and immediately after exposures, which ranged from 20 to 45 minutes. The studies have shown that a combination of noise and WBV do not degrade cognitive performance more than a single stimulus. However, WBV can degrade attention performance after exposure is turned off when drivers have been working under high mental load during exposure. The combined stimuli are also experienced as more annoying and work is more difficult in such conditions. The exposure times and task difficulty levels used in this thesis did not produce biological stress as measured by cortisol. Nevertheless, subjective ratings are sometimes seen as early indicators of other symptoms and with increased task difficulty and/or longer exposure times there may appear other measurable outcomes of the combined stimuli

Different Features of Bilingualism in Relation to Executive Functioning

The notion that the long-term practice of managing two languages is beneficial for the executive control system is an ongoing debate. Criticism have been raised that studies demonstrating a bilingual advantage often suffer from small sample sizes, and do not control for fluid intelligence as a possible confound. Taking those suggested factors into account, focusing on older bilingual age groups and investigating the potential effects of linguistic distances, this study aimed to improve the interpretations of the bilinguals’ advantages. Measures of inhibition (Flanker, Stroop, Simon task) and switching (Number-letter, Color-Shape, Local-global task) were collected in participants in the ages 50-75 years (n = 193). Despite a large study sample, results did not support any beneficial effects related to improve processing costs in executive functioning. Sub-analyses of the two different language groups (Swedish – Finnish / Swedish – English) intended to investigate the effect of linguistic distances did not change this outcome. Future studies exploring the potential long-term term effects of bilingualism would benefit from identifying tests of cognitive control with greater ecological validity and include other measures of cognitive functioning. Language learning interventions may also be a promising tool for future research

The impact of spoken action words on performance in a cross-modal oddball task

In this study a cross-modal oddball task was employed to study the effect that words spokeneither non-urgently or urgently would have on a digit categorization task and if women wouldexhibit greater behavioral inhibitory control. The words were unrelated to the task itself, butrelated to the action required to complete the task. Forty participants (21 women) conducteda computerized categorization task while exposed to a sinewave tone as a standard stimulus(75% of the trials) or a to-be ignored word (press, stop) spoken either non-urgently orurgently as unexpected auditory deviant stimulus (6.25% trials for each category). Urgentwords had sharp intonation and an average fundamental frequency (F0) ranging from 191.9(stop) to 204.6 (press) Hz. Non-urgent words had low intonation with average F0 rangingfrom 103.9.9 (stop) to 120.3 (press) Hz. As expected, deviant distraction and longerresponse times were found by exposure to the word stop, but deviant distraction was notfound to be significant with the word press or due to intonation. While the results showedthat women had in general longer reaction times, there were no gender differences foundrelated to the deviant distraction caused by word or intonation. The present results do notsupport the hypothesis that women have greater behavioral inhibitory control, but there wasevidence that the meaning of the word could influence response times

Reading Habits Among Older Adults in Relation to Level and 15-Year Changes in Verbal Fluency and Episodic Recall

The main objective of this study was to investigate reading habits in older adults in relation to level and 15-year changes in verbal fluency and episodic recall. We examined a sample of 1157 participants (55 years at baseline) up to 15 years after the baseline assessment using latent growth curve modeling of cognitive measures with baseline reading frequency (books, weekly magazines) as a predictor of cognitive level (intercept) and rate of change (slope). Subgroup analyses were performed to investigate the role of an early adult g factor in the association between reading habits and cognitive ability in midlife. Frequent reading of books, but not of magazines, was associated with higher levels of verbal fluency and recall but unrelated to rate of longitudinal decline. Subgroup analyses indicated that the g factor in early adulthood predicted reading and cognitive level in midlife and this factor removed the current association between reading habits and level of cognitive ability (both cognitive factors). The results indicate an enduring relationship between book reading and level of cognitive ability across the adult life span and provide little support of the hypothesis that frequent reading protects against latelife cognitive decline. The extent to which book reading promotes cognitive functioning in childhood/youth remains to be demonstrated. Intervention studies may be useful in this regard

Complexity of Primary Lifetime Occupation and Cognitive Processing

Today, there are a lack of studies focusing on the relationship between occupational complexity and executive functioning. This is noteworthy since executive functions are core aspects of cognitive processing. The present study was aimed to investigate if three occupational complexity factors (with data, people, and things) of main lifetime occupation were related to performance in executive tasks (inhibition, switching, updating). We analyzed cross-sectional data that were available for 225 participants aged 50–75 years. Results from structural equation models showed that higher complexity levels of working with data were related to lower error rates in the updating component of cognitive control. In addition, higher rates of complexity working with people was associated with lower error rates in task-switching, which also persisted after adjustment of fluid intelligence. Complexity with things, however, was not related to performance in the executive tasks. Future studies would benefit from a longitudinal design to investigate if the results from this study also hold in the long term and to further investigate the directionality between factors

Mental demands at work and risk of dementia

High mental demands at work was examined as a possible protective factor to reduce the risk of dementia in 1,277 initially dementia-free participants, aged 60 years and older. The cohort was followed for a mean of 13.6 years. During follow-up, 376 participants developed all-cause dementia (Alzheimer’s disease = 199; vascular dementia = 145). The association between mental demands at work and dementia was analyzed with Cox hazard models, adjusted for a range of covariates. The results revealed no significant association between mental demands at work and incidence of dementia. Based on the measures used in this study, it was concluded that high mental demands at work may not reduce the risk of dementia later on in life