| 1. |
- Roslin, Tomas, et al.
(author)
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A molecular-based identification resource for the arthropods of Finland
- 2022
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In: Molecular Ecology Resources. - : Wiley. - 1755-098X .- 1755-0998. ; 22:2, s. 803-822
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Journal article (peer-reviewed)abstract
- To associate specimens identified by molecular characters to other biological knowledge, we need reference sequences annotated by Linnaean taxonomy. In this study, we (1) report the creation of a comprehensive reference library of DNA barcodes for the arthropods of an entire country (Finland), (2) publish this library, and (3) deliver a new identification tool for insects and spiders, as based on this resource. The reference library contains mtDNA COI barcodes for 11,275 (43%) of 26,437 arthropod species known from Finland, including 10,811 (45%) of 23,956 insect species. To quantify the improvement in identification accuracy enabled by the current reference library, we ran 1000 Finnish insect and spider species through the Barcode of Life Data system (BOLD) identification engine. Of these, 91% were correctly assigned to a unique species when compared to the new reference library alone, 85% were correctly identified when compared to BOLD with the new material included, and 75% with the new material excluded. To capitalize on this resource, we used the new reference material to train a probabilistic taxonomic assignment tool, FinPROTAX, scoring high success. For the full-length barcode region, the accuracy of taxonomic assignments at the level of classes, orders, families, subfamilies, tribes, genera, and species reached 99.9%, 99.9%, 99.8%, 99.7%, 99.4%, 96.8%, and 88.5%, respectively. The FinBOL arthropod reference library and FinPROTAX are available through the Finnish Biodiversity Information Facility (www.laji.fi) at https://laji.fi/en/theme/protax. Overall, the FinBOL investment represents a massive capacity-transfer from the taxonomic community of Finland to all sectors of society.
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| 2. |
- Alakurtti, Kati, et al.
(author)
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Long-term test-retest reliability of striatal and extrastriatal dopamine D-2/3 receptor binding : study with [C-11]raclopride and high-resolution PET
- 2015
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In: Journal of Cerebral Blood Flow and Metabolism. - : SAGE Publications. - 0271-678X .- 1559-7016. ; 35:7, s. 1199-1205
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Journal article (peer-reviewed)abstract
- We measured the long-term test-retest reliability of [C-11]raclopride binding in striatal subregions, the thalamus and the cortex using the bolus-plus-infusion method and a high-resolution positron emission scanner. Seven healthy male volunteers underwent two positron emission tomography (PET) [C-11]raclopride assessments, with a 5-week retest interval. D-2/3 receptor availability was quantified as binding potential using the simplified reference tissue model. Absolute variability (VAR) and intraclass correlation coefficient (ICC) values indicated very good reproducibility for the striatum and were 4.5%/0.82, 3.9%/0.83, and 3.9%/0.82, for the caudate nucleus, putamen, and ventral striatum, respectively. Thalamic reliability was also very good, with VAR of 3.7% and ICC of 0.92. Test-retest data for cortical areas showed good to moderate reproducibility (6.1% to 13.1%). Our results are in line with previous test-retest studies of [C-11]raclopride binding in the striatum. A novel finding is the relatively low variability of [C-11]raclopride binding, providing suggestive evidence that extrastriatal D-2/3 binding can be studied in vivo with [C-11]raclopride PET to be verified in future studies.
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| 3. |
- Bäckman, Lars, et al.
(author)
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Effects of working-memory training on striatal dopamine release
- 2011
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 333:6043, s. 718-
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Journal article (peer-reviewed)abstract
- Updating of working memory has been associated with striato-frontal brain regions and phasic dopaminergic neurotransmission. We assessed raclopride binding to striatal dopamine (DA) D2 receptors during a letter-updating task and a control condition before and after 5 weeks of updating training. Results showed that updating affected DA activity before training and that training further increased striatal DA release during updating. These findings highlight the pivotal role of transient neural processes associated with D2 receptor activity in working memory.
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| 4. |
- Bäckman, Lars, et al.
(author)
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Increased dopamine release after working-memory updating training : Neurochemical correlates of transfer
- 2017
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In: Scientific Reports. - : NATURE PUBLISHING GROUP. - 2045-2322. ; 7
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Journal article (peer-reviewed)abstract
- Previous work demonstrates that working-memory (WM) updating training results in improved performance on a letter-memory criterion task, transfers to an untrained n-back task, and increases striatal dopamine (DA) activity during the criterion task. Here, we sought to replicate and extend these findings by also examining neurochemical correlates of transfer. Four positron emission tomography (PET) scans using the radioligand raclopride were performed. Two of these assessed DAD2 binding (letter memory; n-back) before 5 weeks of updating training, and the same two scans were performed post training. Key findings were (a) pronounced training-related behavioral gains in the lettermemory criterion task, (b) altered striatal DAD2 binding potential after training during letter-memory performance, suggesting training-induced increases in DA release, and (c) increased striatal DA activity also during the n-back transfer task after the intervention, but no concomitant behavioral transfer. The fact that the training-related DA alterations during the transfer task were not accompanied by behavioral transfer suggests that increased DA release may be a necessary, but not sufficient, condition for behavioral transfer to occur.
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| 5. |
- Das, Biswanath, et al.
(author)
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Water oxidation catalyzed by molecular di- and nonanuclear Fe complexes: importance of a proper ligand framework
- 2016
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In: Dalton Transactions. - : ROYAL SOC CHEMISTRY. - 1477-9226 .- 1477-9234. ; 45:34, s. 13289-13293
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Journal article (peer-reviewed)abstract
- The synthesis of two molecular iron complexes, a dinuclear iron(III,III) complex and a nonanuclear iron complex, based on the di-nucleating ligand 2,2-(2-hydroxy-5-methyl-1,3-phenylene)bis(1H-benzo[d]imidazole-4-carboxylic acid) is described. The two iron complexes were found to drive the oxidation of water by the one-electron oxidant [Ru(bpy)(3)](3+).
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| 6. |
- Ekblad, Laura L., et al.
(author)
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Midlife insulin resistance, APOE genotype, and late-life brain amyloid accumulation
- 2018
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In: Neurology. - : Lippincott Williams & Wilkins. - 0028-3878 .- 1526-632X. ; 90:13, s. e1150-e1157
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Journal article (peer-reviewed)abstract
- Objective To examine whether midlife insulin resistance is an independent risk factor for brain amyloid accumulation in vivo after 15 years, and whether this risk is modulated by APOE epsilon 4 genotype. Methods This observational study examined 60 elderly volunteers without dementia (mean age at baseline 55.4 and at follow-up 70.9 years, 55.5% women) from the Finnish population-based, nationwide Health2000 study with [C-11]Pittsburgh compound B-PET imaging in 2014-2016. The participants were recruited according to their homeostatic model assessment of insulin resistance (HOMA-IR) values in the year 2000, and their APOE epsilon 4 genotype. The exposure group (IR+, n = 30) consisted of individuals with HOMA-IR > 2.17 at baseline (highest tertile of the Health2000 study population), and the control group (IR-, n = 30) consisted of individuals with HOMA-IR < 1.25 at baseline (lowest tertile). The groups were enriched for APOE epsilon 4 carriers, resulting in 50% (n = 15) APOE epsilon 4 carriers in both groups. Analyses were performed with multivariate logistic and linear regression. Results An amyloid-positive PET scan was found in 33.3% of the IR-group and 60.0% of the IR+ group (odds ratio 3.0, 95% confidence interval 1.1-8.9, p = 0.04). The increased risk was seen in carriers and noncarriers of APOE epsilon 4 genotype. Higher midlife, but not late-life continuous HOMA-IR was associated with a greater brain amyloid burden at follow-up after multivariate adjustments for other cognitive and metabolic risk factors (ss = 0.11, 95% confidence interval 0.002-0.22, p = 0.04). Conclusions These results indicate that midlife insulin resistance is an independent risk factor for brain amyloid accumulation in elderly individuals without dementia.
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| 7. |
- Fellman, Daniel, et al.
(author)
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Beginning of the Pandemic : COVID-19-Elicited Anxiety as a Predictor of Working Memory Performance
- 2020
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In: Frontiers in Psychology. - : Frontiers Media S.A.. - 1664-1078. ; 11
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Journal article (peer-reviewed)abstract
- Increasing evidence indicates that the coronavirus disease 2019 (COVID-19) pandemic is associated with adverse psychological effects, including heightened levels of anxiety. This study examined whether COVID-19-related anxiety levels during the early stage of the pandemic predicted demanding working memory (WM) updating performance. Altogether, 201 healthy adults (age range, 18-50) mostly from North America and the British Isles were recruited to this study via the crowdsourcing site . The results showed that higher levels of COVID-19-related anxiety during the first weeks of the pandemic outbreak were associated with poorer WM performance as measured by the n-back paradigm. Critically, the unique role of COVID-19-related anxiety on WM could not be explained by demographic factors, or other psychological factors such as state and trait anxiety or fluid intelligence. Moreover, across three assessment points spanning 5-6 weeks, COVID-19-related anxiety levels tended to decrease over time. This pattern of results may reflect an initial psychological "shock wave" of the pandemic, the cognitive effects of which may linger for some time, albeit the initial anxiety associated with the pandemic would change with habituation and increasing information. Our results contribute to the understanding of cognitive-affective reactions to a major disaster.
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| 8. |
- Fellman, Daniel, et al.
(author)
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The role of strategy use in working memory training outcomes
- 2020
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In: Journal of memory and language (Print). - : Elsevier. - 0749-596X .- 1096-0821. ; 110
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Journal article (peer-reviewed)abstract
- Cognitive mechanisms underlying the limited transfer effects of working memory (WM) training remain poorly understood. We tested in detail the Strategy Mediation hypothesis, according to which WM training generates task-specific strategies that facilitate performance on the trained task and its untrained variants. This large-scale pre-registered randomized controlled trial (n = 258) used a 4-week adaptive WM training with a single digit n-back task. Strategy use was probed with open-ended strategy reports. We employed a Strategy training group (n = 73) receiving external strategy instruction, a Traditional training group (n = 118) practicing without strategy instruction, and Passive controls (n = 67). Both training groups showed emerging transfer to untrained n-back task variants already at intermediate test after 3 training sessions, extending to all untrained n-back task variants at posttest after 12 training sessions. The Strategy training group outperformed the Traditional training group only at the beginning of training, indicating short-lived strategy manipulation effects. Importantly, in the Traditional training group, strategy evolvement modulated the gains in the trained and untrained n -back tasks, supporting the Strategy Mediation hypothesis. Our results concur with the view of WM training as cognitive skill learning.
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| 9. |
- Forsberg, Alicia, et al.
(author)
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Strategy mediation in working memory training in younger and older adults
- 2020
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In: Quarterly Journal of Experimental Psychology. - : Sage Publications. - 1747-0218 .- 1747-0226. ; 73:8, s. 1206-1226
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Journal article (peer-reviewed)abstract
- Working memory (WM) training with the N-Back task has been argued to improve cognitive capacity and general cognitive abilities (the Capacity Hypothesis of training), although several studies have shown little or no evidence for such improvements beyond tasks that are very similar to the trained task. Laine et al. demonstrated that instructing young adult participants to use a specific visualisation strategy for N-back training resulted in clear, generalised benefits from only 30 min of training (Strategy Mediation Hypothesis of training). Here, we report a systematic replication and extension of the Laine et al. study, by administering 60 younger and 60 older participants a set of WM tasks before and after a 30-min N-back training session. Half the participants were instructed to use a visualisation strategy, the others received no instruction. The pre-post test battery encompassed a criterion task (digit N-back), two untrained tasks N-back tasks (letters and colours), and three structurally different WM tasks. The instructed visualisation strategy significantly boosted at least some measures of N-back performance in participants of both age groups, although the strategy generally appeared more difficult to implement and less beneficial for older adults. However, the strategy did not improve performance on structurally different WM tasks. We also found significant associations between N-back performance and the type and level of detail of self-generated strategies in the uninstructed participants, as well as age group differences in reported strategy types. WM performance appeared to partly reflect the application of strategies, and Strategy Mediation should be considered to understand the mechanisms of WM training. Claims of efficient training should demonstrate useful improvement beyond task-specific strategies.
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| 10. |
- Gronholm-Nyman, Petra, et al.
(author)
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Limited Effects of Set Shifting Training in Healthy Older Adults
- 2017
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In: Frontiers in Aging Neuroscience. - : Frontiers Media S.A.. - 1663-4365. ; 9
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Journal article (peer-reviewed)abstract
- Our ability to flexibly shift between tasks or task sets declines in older age. As this decline may have adverse effects on everyday life of elderly people, it is of interest to study whether set shifting ability can be trained, and if training effects generalize to other cognitive tasks. Here, we report a randomized controlled trial where healthy older adults trained set shifting with three different set shifting tasks. The training group (n = 17) performed adaptive set shifting training for 5 weeks with three training sessions a week (45 min/session), while the active control group (n = 16) played three different computer games for the same period. Both groups underwent extensive pre-and post-testing and a 1-year follow-up. Compared to the controls, the training group showed significant improvements on the trained tasks. Evidence for near transfer in the training group was very limited, as it was seen only on overall accuracy on an untrained computerized set shifting task. No far transfer to other cognitive functions was observed. One year later, the training group was still better on the trained tasks but the single near transfer effect had vanished. The results suggest that computerized set shifting training in the elderly shows long-lasting effects on the trained tasks but very little benefit in terms of generalization.
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| 11. |
- Haarala, Christian, et al.
(author)
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Electromagnetic field emitted by 902 MHz phones shows no effects on children's cognitive function
- 2005
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In: Bioelectromagnetics. - : Wiley-Liss. - 0197-8462 .- 1521-186X. ; 26:S7, s. S144-S150
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Journal article (peer-reviewed)abstract
- The present study investigated the potential effects of a standard 902 MHz global system for mobile communication (GSM) mobile phone on 10–14 years old children’s cognitive function. A total of 32 children (16 boys, 16 girls) participated with their own and parental consent. The subjects were 10– 14 years old (mean 12.1 years, SD 1.1). They performed a battery of cognitive tests twice in a counterbalanced order: once while exposed to an active mobile phone and once during exposure to an inactive phone. The tests were selected from those we used earlier with adults. The statistical analyses showed no significant differences between the mobile phone off and on conditions in reaction times and accuracy over all tests or in any single test. It was concluded that a standard mobile phone has no effect on children’s cognitive function as measured by response speed and accuracy. The present results challenge some earlier findings suggesting that the electromagnetic field (EMF) created by an active mobile phone would facilitate cognitive functioning.
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| 12. |
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| 13. |
- Kumsars, Indulis, et al.
(author)
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Randomised comparison of provisional side branch stenting versus a two-stent strategy for treatment of true coronary bifurcation lesions involving a large side branch : the Nordic-Baltic Bifurcation Study IV
- 2020
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In: Open heart. - : BMJ Publishing Group Ltd. - 2053-3624. ; 7:1
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Journal article (peer-reviewed)abstract
- Background: It is still uncertain whether coronary bifurcations with lesions involving a large side branch (SB) should be treated by stenting the main vessel and provisional stenting of the SB (simple) or by routine two-stent techniques (complex). We aimed to compare clinical outcome after treatment of lesions in large bifurcations by simple or complex stent implantation.Methods: The study was a randomised, superiority trial. Enrolment required a SB >= 2.75 mm, >= 50% diameter stenosis in both vessels, and allowed SB lesion length up to 15 mm. The primary endpoint was a composite of cardiac death, non-procedural myocardial infarction and target lesion revascularisation at 6 months. Two-year clinical follow-up was included in this primary reporting due to lower than expected event rates.Results: A total of 450 patients were assigned to simple stenting (n = 221) or complex stenting (n=229) in 14 Nordic and Baltic centres. Two-year follow-up was available in 218 (98.6%) and 228 (99.5%) patients, respectively. The primary endpoint of major adverse cardiac events (MACE) at 6 months was 5.5% vs 2.2% (risk differences 3.2%, 95% CI -0.2 to 6.8, p=0.07) and at 2 years 12.9% vs 8.4% (HR 0.63, 95% CI 0.35 to 1.13, p = 0.12) after simple versus complex treatment. In the subgroup treated by newer generation drug-eluting stents, MACE was 12.0% vs 5.6% (HR 0.45, 95% CI 0.17 to 1.17, p = 0.10) after simple versus complex treatment.Conclusion: In the treatment of bifurcation lesions involving a large SB with ostial stenosis, routine two-stent techniques did not improve outcome significantly compared with treatment by the simpler main vessel stenting technique after 2 years.
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| 14. |
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| 15. |
- Lehtonen, Minna, et al.
(author)
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Testing the Stem Dominance Hypothesis : Meaning Analysis of Inflected Words and Prepositional Phrases
- 2014
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In: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:3, s. e93136-
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Journal article (peer-reviewed)abstract
- We tested the hypothesis that lexical-semantic access of inflected words is governed by the word stem. Object drawings overlaid with a dot/arrow marking position/movement were matched with corresponding linguistic expressions like from the house. To test whether the stem dominates lexical-semantic access irrespective of its position, we used Swedish prepositional phrases (locative information via preposition immediately preceding the stem) or Finnish case-inflected words (locative information via suffix immediately following the stem). Both in monolingual Swedish and in bilingual Finnish-Swedish speakers, correct stems with incorrect prepositions/case-endings were hardest to reject. This finding supports the view that the stem is indeed the dominant unit in meaning access of inflected words.
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| 16. |
- Pirinen, Riku, et al.
(author)
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The Outcome after Endovascular and Open Repair of Abdominal Aortic Aneurysms-A Binational Study Conducted between 1998 and 2017
- 2024
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In: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 13:15
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Journal article (peer-reviewed)abstract
- Objective: We aimed to analyse patient outcomes following open (OAR) or endovascular repair (EVAR) of an abdominal aortic aneurysm (AAA) in Finland and Sweden from 1998 to 2017. Both intact and ruptured AAAs (rAAAs) were included in the analysis.Methods: Patient-level data from national registries in Finland and Sweden were analysed, pairing operations for intact and ruptured AAA repair with mortality data (date of death). All-cause mortality was the primary endpoint. Anonymized patient data from both countries were pooled, comprising a total of 32,324 operations. Ruptured and intact AAAs were considered separately. In total, EVAR was performed on 9619 intact AAAs and 1470 rAAAs, while OAR was performed on 13,241 intact AAAs and 7994 rAAAs. The patient's age, sex and the date of operation were obtained as demographic information. Cox regression and Kaplan-Meier analyses were used to evaluate long-term (10-year) survival after the treatment of AAA or rAAA with either modality. Kaplan-Meier analysis was performed in three different age groups (<65 years, 65-79 years and >= 80 years).Results: Considering all age groups together, the 1-, 3- and 10-year Kaplan-Meier survival rates after EVAR were 93.4%, 80.5% and 35.3%, respectively, for intact AAA repair and 67.2%, 55.9% and 22.2%, respectively, for rAAA repair. For OAR of intact AAAs, the 1-, 3- and 10-year Kaplan-Meier survival rates were 92.1%, 84.8% and 48.7%, respectively. The respective rates for OAR of rAAAs were 55.4%, 49.3% and 24.6%. In a Cox regression analysis, a more recent year of operation was associated with improved survival, and older age affected survival negatively for both intact and ruptured AAA repair. If patients survived the first 90 days after the operation, the survival after intact AAA repair was 13.5 years for those <65 years (general population: 18.0 years), and 7.3 years for those >= 80 years (general population: 7.9 years). After rAAA repair, the mean survival was 13.1 years for patients <65 years and 5.5 years for patients >= 80 years, respectively.Conclusions: The long-term survival of patients undergoing intact AAA treatment at the age of 80 or older is close to that of the general population, provided they survive the operation. Conversely, for patients younger than 65, the long-term survival is markedly worse. The long-term survival of AAA patients has improved over time. Open surgery is still a safe and effective option for young patients undergoing intact AAA repair. Our results support the ESVS guidelines recommendation of EVAR being the first-line treatment for patients with rAAA.
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| 17. |
- Png, C. Y. Maximilian, et al.
(author)
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Effect of EVAR on International Ruptured AAA Mortality-Sex and Geographic Disparities
- 2024
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In: Journal of Clinical Medicine. - : MDPI. - 2077-0383. ; 13:9
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Journal article (peer-reviewed)abstract
- Background: We sought to investigate the differential impact of EVAR (endovascular aneurysm repair) vis-á-vis OSR (open surgical repair) on ruptured AAA (abdominal aortic aneurysm) mortality by sex and geographically.Methods: We performed a retrospective study of administrative data on EVAR from state statistical agencies, vascular registries, and academic publications, as well as ruptured AAA mortality rates from the World Health Organization for 14 14 states across Australasia, East Asia, Europe, and North America.Results: Between 2011-2016, the proportion of treatment of ruptured AAAs by EVAR increased from 26.1 to 43.8 percent among females, and from 25.7 to 41.2 percent among males, and age-adjusted ruptured AAA mortality rates fell from 12.62 to 9.50 per million among females, and from 34.14 to 26.54 per million among males. The association of EVAR with reduced mortality was more than three times larger (2.2 vis-á-vis 0.6 percent of prevalence per 10 percentage point increase in EVAR) among females than males. The association of EVAR with reduced mortality was substantially larger (1.7 vis-á-vis 1.1 percent of prevalence per 10 percentage point increase in EVAR) among East Asian states than European+ states.Conclusions: The increasing adoption of EVAR coincided with a decrease in ruptured AAA mortality. The relationship between EVAR and mortality was more pronounced among females than males, and in East Asian than European+ states. Sex and ethnic heterogeneity should be further investigated.
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| 18. |
- Portin, Marja, et al.
(author)
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L1 effects on the processing of inflected nouns in L2
- 2008
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In: Acta Psychologica. - : Elsevier BV. - 0001-6918 .- 1873-6297. ; 128:3, s. 452-465
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Journal article (peer-reviewed)abstract
- This study investigated the effect of L1 on the recognition of L2 Swedish inflected nouns. Two groups of late L2 learners with typologically very different native languages, Hungarian (agglutinative) and Chinese (isolating), participated in a visual lexical decision experiment. The target words were matched inflected vs. monomorphemic nouns from three frequency levels. The Hungarian group showed it morphological processing cost (longer reaction times for the infected words) for low and medium frequency words but not for high frequency words, suggesting morphological decomposition of low and medium frequency Swedish inflected nouns. In contrast, for the Chinese group the reaction times of the inflected vs. monomorphemic words were similar at all frequency levels, indicating full-form processing of all the inflected nouns. This cross-language difference suggests that L1 can exert an effect on the morphological processing in L2. The application of full-form processing for the Swedish inflected nouns in the Chinese group might reflect strategy transfer from their isolating native language to Swedish.
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| 19. |
- Ritakallio, Liisa, et al.
(author)
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The Pursuit of Effective Working Memory Training : a Pre-registered Randomised Controlled Trial with a Novel Varied Training Protocol
- 2022
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In: Journal of Cognitive Enhancement. - : Springer. - 2509-3290 .- 2509-3304. ; 6, s. 232-247
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Journal article (peer-reviewed)abstract
- Working memory (WM) training, typically entailing repetitive practice with one or two tasks, has mostly yielded only limited task-specific transfer effects. We developed and tested a new WM training approach where the task paradigm, stimulus type, and predictability of the stimulus sequence were constantly altered during the 4-week training period. We expected that this varied training protocol would generate more extensive transfer by facilitating the use of more general strategies that could be applied to a range of WM tasks. Pre-post transfer effects following varied training (VT group, n = 60) were compared against traditional training (TT group, training a single adaptive WM task, n = 63), and active controls (AC, n = 65). As expected, TT evidenced strong task-specific near transfer as compared to AC. In turn, VT exhibited task-specific near transfer only on one of the measures, and only as compared to the TT group. Critically, no evidence for task-general near transfer or far transfer effects was observed. In sum, the present form of VT failed to demonstrate broader transfer. Nevertheless, as VT has met with success in other cognitive domains, future studies should probe if and how it would be possible to design WM training protocols that promote structural learning where common features of specific tasks would be identified and utilised when selecting strategies for novel memory tasks.
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| 20. |
- Salmi, Juha, et al.
(author)
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Disentangling the Role of Working Memory in Parkinson's Disease
- 2020
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In: Frontiers in Aging Neuroscience. - : Frontiers Media S.A.. - 1663-4365. ; 12
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Journal article (peer-reviewed)abstract
- Working memory (WM) represents a core cognitive function with a major striatal contribution, and thus WM deficits, commonly observed in Parkinson's disease (PD), could also relate to many other problems in PD patients. Our online study aimed to determine the subdomains of WM that are particularly affected in PD and to clarify the links between WM and everyday cognitive deficits, other executive functions, psychiatric and PD symptoms, as well as early cognitive impairment. Fifty-two mild-to-moderate PD patients and 54 healthy controls performed seven WM tasks tapping selective updating, continuous monitoring, or maintenance of currently active information. Self-ratings of everyday cognition, depression, and apathy symptoms, as well as screenings of global cognitive impairment, were also collected. The data were analyzed using structural equation modeling. Of the three WM domains, only selective updating was directly predictive of PD group membership. More widespread WM deficits were observed only in relation to global cognitive impairment in PD patients. Self-rated everyday cognition or psychiatric symptoms were not linked to WM performance but correlated with each other. Our findings suggest that WM has a rather limited role in the clinical manifestation of PD. Nevertheless, due to its elementary link to striatal function, the updating component of WM could be a candidate for a cognitive marker of PD also in patients who are otherwise cognitively well-preserved.
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| 21. |
- Salmi, Juha, et al.
(author)
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Working memory training mostly engages general-purpose large-scale networks for learning
- 2018
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In: Neuroscience and Biobehavioral Reviews. - : Elsevier. - 0149-7634 .- 1873-7528. ; 93, s. 108-122
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Research review (peer-reviewed)abstract
- The present meta-analytic study examined brain activation changes following working memory (WM) training, a form of cognitive training that has attracted considerable interest. Comparisons with perceptual-motor (PM) learning revealed that WM training engages domain-general large-scale networks for learning encompassing the dorsal attention and salience networks, sensory areas, and striatum. Also the dynamics of the training-induced brain activation changes within these networks showed a high overlap between WM and PM training. The distinguishing feature for WM training was the consistent modulation of the dorso- and ventrolateral prefrontal cortex (DLPFC/VLPFC) activity. The strongest candidate for mediating transfer to similar untrained WM tasks was the frontostriatal system, showing higher striatal and VLPFC activations, and lower DLPFC activations after training. Modulation of transfer-related areas occurred mostly with longer training periods. Overall, our findings place WM training effects into a general perception-action cycle, where some modulations may depend on the specific cognitive demands of a training task.
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| 22. |
- Soveri, Anna, et al.
(author)
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Modulation of Auditory Attention by Training Evidence From Dichotic Listening
- 2013
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In: Experimental psychology (Göttingen). - : Hogrefe Publishing Group. - 1618-3169 .- 2190-5142. ; 60:1, s. 44-52
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Journal article (peer-reviewed)abstract
- We studied the effects of training on auditory attention in healthy adults with a speech perception task involving dichotically presented syllables. Training involved bottom-up manipulation (facilitating responses from the harder-to-report left ear through a decrease of right-ear stimulus intensity), top-down manipulation (focusing attention on the left-ear stimuli through instruction), or their combination. The results showed significant training-related effects for top-down training. These effects were evident as higher overall accuracy rates in the forced-left dichotic listening (DL) condition that sets demands on attentional control, as well as a response shift toward left-sided reports in the standard DL task. Moreover, a transfer effect was observed in an untrained auditory-spatial attention task involving bilateral stimulation where top-down training led to a relatively stronger focus on left-sided stimuli. Our results indicate that training of attentional control can modulate the allocation of attention in the auditory space in adults. Malleability of auditory attention in healthy adults raises the issue of potential training gains in individuals with attentional deficits.
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| 23. |
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| 24. |
- Toppala, Sini, et al.
(author)
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Association of Early β-Amyloid Accumulation and Neuroinflammation Measured With [11C]PBR28 in Elderly Individuals Without Dementia.
- 2021
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In: Neurology. - : Wolters Kluwer. - 1526-632X .- 0028-3878. ; 96:12
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Journal article (peer-reviewed)abstract
- To examine whether early β-amyloid (Aβ) accumulation and metabolic risk factors are associated with neuroinflammation in elderly individuals without dementia.We examined 54 volunteers (mean age 70.0 years, 56% women, 51% APOE ɛ4 carriers) with the translocator protein (TSPO) tracer [11C]PBR28 to assess neuroinflammation and with [11C] Pittsburgh compound B (PiB) to assess cerebral Aβ accumulation. [11C]PBR28 and [11C]PiB standardized uptake value ratios (SUVRs) were quantified in 6 regions of interests by using the cerebellar cortex as a pseudo-reference and reference region, respectively. Fasting venous glucose, insulin, and high-sensitivity C-reactive protein (hs-CRP) values were determined. Homeostatic model assessment of insulin resistance (HOMA-IR) was calculated. A subset of individuals (n = 11) underwent CSF sampling, and Aβ40, Aβ42, total tau, phospho-tau, soluble TREM2, and YKL-40 levels were measured.Among the whole study group, no significant association was found between [11C]PiB and [11C]PBR28 SUVR composite scores (slope 0.02, p = 0.30). However, higher [11C]PiB binding was associated with higher [11C]PBR28 binding among amyloid-negative ([11C]PiB composite score ≤1.5) (TSPO genotype-, age- and sex-adjusted slope 0.26, p = 0.008) but not among amyloid-positive (slope -0.004, p = 0.88) participants. Higher CSF soluble TREM2 (rs = 0.72, p = 0.01) and YKL-40 (rs = 0.63, p = 0.04) concentrations were associated with a higher [11C]PBR28 composite score. Higher body mass index, HOMA-IR, and hs-CRP were associated with higher [11C]PBR28 binding in brain regions where Aβ accumulation is first detected in Alzheimer disease.While there was no association between amyloid and neuroinflammation in the overall study group, neuroinflammation was associated with amyloid among the subgroup at early stages of amyloid pathology.
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| 25. |
- Toppala, Sini, et al.
(author)
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Midlife Insulin Resistance as a Predictor for Late-Life Cognitive Function and Cerebrovascular Lesions
- 2019
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In: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 72:1, s. 215-228
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Journal article (peer-reviewed)abstract
- Background: Type 2 diabetes (T2DM) increases the risk for Alzheimer’s disease (AD) but not for AD neuropathology. The association between T2DM and AD is assumed to be mediated through vascular mechanisms. However, insulin resistance (IR), the hallmark of T2DM, has been shown to associate with AD neuropathology and cognitive decline.Objective: To evaluate if midlife IR predicts late-life cognitive performance and cerebrovascular lesions (white matter hyperintensities and total vascular burden), and whether cerebrovascular lesions and brain amyloid load are associated with cognitive functioning.Methods: This exposure-to-control follow-up study examined 60 volunteers without dementia (mean age 70.9 years) with neurocognitive testing, brain 3T-MRI and amyloid-PET imaging. The volunteers were recruited from the Finnish Health 2000 survey (n = 6062) to attend follow-up examinations in 2014–2016 according to their insulin sensitivity in 2000 and their APOE genotype. The exposure group (n = 30) had IR in 2000 and the 30 controls had normal insulin sensitivity. There were 15 APOE ɛ4 carriers per group. Statistical analyses were performed with multivariable linear models.Results: At follow-up the IR+group performed worse on executive functions (p = 0.02) and processing speed (p = 0.007) than the IR- group. The groups did not differ in cerebrovascular lesions. No associations were found between cerebrovascular lesions and neurocognitive test scores. Brain amyloid deposition associated with slower processing speed.Conclusion: Midlife IR predicted poorer executive functions and slower processing speed, but not cerebrovascular lesions. Brain amyloid deposition was associated with slower processing speed. The association between midlife IR and late-life cognition might not be mediated through cerebrovascular lesions measured here.
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| 26. |
- Waris, Otto, et al.
(author)
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Spontaneous strategy use during a working memory updating task
- 2021
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In: Acta Psychologica. - : Elsevier. - 0001-6918 .- 1873-6297. ; 212
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Journal article (peer-reviewed)abstract
- Cognitive skill learning postulates strategy generation and implementation when people learn to perform new tasks. Here we followed self-reported strategy use and objective performance in a working memory (WM) updating task to reveal strategy development that should take place when faced with this novel task. In two pre-registered online experiments with healthy adults, we examined short-term strategy acquisition in a ca 20-30-minute adaptive n-back WM task with 15 task blocks by collecting participants' strategy reports after each block. Experiment 1 showed that (a) about half of the participants reported using a strategy already during the very first task block, (b) changes in selected strategy were most common during the initial task blocks, and (c) more elaborated strategy descriptions predicted better task performance. Experiment 2 mostly replicated these findings, and it additionally showed that compared to open-ended questions, the use of repeated list-based strategy queries influenced subsequent strategy use and task performance, and also indicated higher rates of strategy implementation and strategy change during the task. Strategy use was also a significant predictor of n-back performance, albeit some of the variance it explained was shared with verbal productivity that was measured with a picture description task. The present results concur with the cognitive skill learning perspective and highlight the dynamics of carrying out a demanding cognitive task.
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| 27. |
- Waris, Otto, et al.
(author)
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Stimulus novelty, task demands, and strategy use in episodic memory
- 2021
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In: Quarterly Journal of Experimental Psychology. - : Sage Publications. - 1747-0218 .- 1747-0226. ; 74:5, s. 872-888
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Journal article (peer-reviewed)abstract
- Cognitive task performance is a dynamic process that evolves over time, starting from the first encounters with a task. An important aspect of these task dynamics is the employment of strategies to support successful performance and task acquisition. Focusing on episodic memory performance, we: (1) tested two hypotheses on the effects of novelty and task difficulty on strategy use, (2) replicated our previous results regarding strategy use in a novel memory task, and (3) evaluated whether repeated open-ended strategy queries affect task performance and/or strategy use. The present pre-registered online study comprised 161 adult participants who were recruited through the Prolific crowdsourcing platform. We employed two separate 5-block list learning tasks, one with 10 pseudowords and the other with 18 common nouns, and collected recall performance and strategy reports for each block. Using Bayesian linear mixed effects models, the present findings (1) provide some support for the hypothesis that task-initial strategy development is not triggered only by task novelty, but can appear also in a familiar, moderately demanding task; (2) replicate earlier findings from an adaptive working memory task indicating strategy use from the beginning of a task, associations between strategy use and objective task performance, and only modest agreement between open-ended versus list-based strategy reports; and (3) indicate that repeated open-ended strategy reports do not affect objective recall. We conclude that strategy use is an important aspect of memory performance right from the start of a task, and it undergoes development at the initial stages depending on task characteristics. In a larger perspective, the present results concur with the views of skill learning and adaptivity in cognitive task performance.
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