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1.
Am J Psychiatry ; 181(10): 920-934, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39350613

RESUMO

OBJECTIVE: In schizophrenia, impaired working memory is associated with transcriptome alterations in layer 3 pyramidal neurons (L3PNs) in the dorsolateral prefrontal cortex (DLPFC). Distinct subtypes of L3PNs that send axonal projections to the DLPFC in the opposite hemisphere (callosal projection [CP] neurons) or the parietal cortex in the same hemisphere (ipsilateral projection [IP] neurons) play critical roles in working memory. However, how the transcriptomes of these L3PN subtypes might shift during late postnatal development when working memory impairments emerge in individuals later diagnosed with schizophrenia is not known. The aim of this study was to characterize and compare the transcriptome profiles of CP and IP L3PNs across developmental transitions from prepuberty to adulthood in macaque monkeys. METHODS: The authors used retrograde labeling to identify CP and IP L3PNs in the DLPFC of prepubertal, postpubertal, and adult macaque monkeys, and used laser microdissection to capture these neurons for RNA sequencing. RESULTS: At all three ages, CP and IP L3PNs had distinct transcriptomes, with the number of genes differentially expressed between neuronal subtypes increasing with age. For IP L3PNs, age-related shifts in gene expression were most prominent between prepubertal and postpubertal animals, whereas for CP L3PNs such shifts were most prominent between postpubertal and adult animals. CONCLUSIONS: These findings demonstrate the presence of cell type-specific profiles and developmental trajectories of the transcriptomes of PPC-projecting IP and DLPFC-projecting CP L3PNs in monkey DLPFC. The evidence that IP L3PNs reach a mature transcriptome earlier than CP L3PNs suggests that these two subtypes differentially contribute to the maturation of working memory performance across late postnatal development and that they may be differentially vulnerable to the disease process of schizophrenia at specific stages of postnatal development.


Assuntos
Células Piramidais , Esquizofrenia , Transcriptoma , Animais , Esquizofrenia/genética , Esquizofrenia/patologia , Esquizofrenia/metabolismo , Células Piramidais/metabolismo , Masculino , Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal Dorsolateral , Macaca mulatta , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/crescimento & desenvolvimento , Feminino
2.
Mol Brain ; 17(1): 72, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354549

RESUMO

Working memory (WM) is essential for the temporary storage and processing of information required for complex cognitive tasks and relies on neuronal theta and gamma oscillations. Given the limited capacity of WM, researchers have investigated various methods to improve it, including transcranial alternating current stimulation (tACS), which modulates brain activity at specific frequencies. One particularly promising approach is theta-gamma peak-coupled-tACS (TGCp-tACS), which simulates the natural interaction between theta and gamma oscillations that occurs during cognitive control in the brain. The aim of this study was to improve WM in healthy young adults with TGCp-tACS, focusing on both behavioral and neurophysiological outcomes. Thirty-one participants completed five WM tasks under both sham and verum stimulation conditions. Electroencephalography (EEG) recordings before and after stimulation showed that TGCp-tACS increased power spectral density (PSD) in the high-gamma region at the stimulation site, while PSD decreased in the theta and delta regions throughout the cortex. From a behavioral perspective, although no significant changes were observed in most tasks, there was a significant improvement in accuracy in the 14-item Sternberg task, indicating an improvement in phonological WM. In conclusion, TGCp-tACS has the potential to promote and improve the phonological component of WM. To fully realize the cognitive benefits, further research is needed to refine the stimulation parameters and account for individual differences, such as baseline cognitive status and hormonal factors.


Assuntos
Memória de Curto Prazo , Estimulação Transcraniana por Corrente Contínua , Humanos , Memória de Curto Prazo/fisiologia , Masculino , Feminino , Adulto Jovem , Estimulação Transcraniana por Corrente Contínua/métodos , Ritmo Teta/fisiologia , Ritmo Gama/fisiologia , Eletroencefalografia , Adulto , Estimulação Elétrica , Comportamento/fisiologia
3.
Indian J Otolaryngol Head Neck Surg ; 76(5): 4146-4152, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39376345

RESUMO

The present study aimed to assess the central auditory processing abilities and working memory in children with non-syndromic cleft lip and palate (NSCLP) and to compare with the developed normative and craniofacially normal peers. Sixteen NSCLP children aged 7 to 12 years and fifteen craniofacially normal peers were recruited in this study. Speech perception in noise Kannada (SPIN-K), gap detection threshold (GDT), dichotic consonant-vowel (DCV), and masking level difference (MLD) tests were administered to assess various central auditory processing abilities. Working memory abilities were assessed by using forward-digit span and backward-digit span tests. The results showed significant differences in SPIN-K, dichotic CV, GDT, forward digit, and backward digit span scores between children with NSCLP and craniofacially normal peers. Thus, it can be concluded from the present study that children with NSCLP have a risk of developing auditory processing deficits. To conclude, assessment of central auditory processing abilities in children with NSCLP is recommended.

4.
Front Aging Neurosci ; 16: 1454755, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376507

RESUMO

Background: Working memory (WM) loss, which can lead to a loss of independence, and declines in the quality of life of older adults, is becoming an increasingly prominent issue affecting the ageing population. Transcranial direct current stimulation (tDCS), a non-invasive brain stimulation technique, is emerging as a potential alternative to pharmacological treatments that shows promise for enhancing WM capacity and May enhance the effects of cognitive training (CT) interventions. Objective: The purpose of this meta-analysis was to explore how different tDCS protocols in combination with CT enhanced WM in healthy older adults. Methods: Randomized controlled trials (RCTs) exploring the effects of tDCS combined with CT on WM in healthy older adults were retrieved from the Web of Science, PubMed, Embase, Scopus and the Cochrane Library databases. The search time period ranged from database inception to January 15, 2024. Methodological quality of the trials was assessed using the risk-of-bias criteria for RCTs from the Cochrane Collaboration Network, and RevMan 5.3 (Cochrane, London, United Kingdom) was used for the meta-analysis of the final literature outcomes. Results: Six RCTs with a total of 323 participants were ultimately included. The results of the meta-analysis show that tDCS combined with CT statistically significantly improves WM performance compared to the control sham stimulation group in healthy older adults [standard mean difference (SMD) = 0.35, 95% CI: 0.11-0.59, I 2 = 0%, Z = 2.86, p = 0.004]. The first subgroup analysis indicated that, when the stimulus intensity was 2 mA, a statistically significant improvement in WM performance in healthy older adults was achieved (SMD = 0.39, 95% CI: 0.08-0.70, I 2 = 6%, Z = 2.46, p = 0.01). The second subgroup analysis showed that long-term intervention (≥ 10 sessions) with tDCS combined with CT statistically significantly improved WM compared to the control group in healthy older adults (SMD = 0.72, 95% CI: 0.22-1.21, I 2 = 0%, Z = 2.85, p = 0.004). Conclusion: tDCS combined with CT statistically significantly improves WM in healthy older adults. For the stimulus parameters, long-term interventions (≥ 10 sessions) with a stimulation intensity of 2 mA are the most effective.

5.
Front Psychol ; 15: 1399388, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39377058

RESUMO

Introduction: The development of reading and complex executive functions is fundamental for achieving social, academic, and professional success. So far, there is no single neuropsychological instrument that comprehensively assesses the domains of inhibitory control, cognitive flexibility, working memory, and reading comprehension. To assess executive functions related to reading, the "Assessment of Reading and Executive Functions" (AREF) was developed. In this study, we show initial evidence of validity and reliability for four subtests - Graphophonological-Semantic Flexibility, Inhibitory Control, Flexibility, and Working Memory. Methods: A total of 93 students from 4th to 9th grade, aged 8-14, in public (n = 61) and private (n = 32) schools were evaluated. Tasks from the AREF instrument, as well as measures of reading comprehension, inhibitory control, cognitive flexibility, working memory, and intelligence, were administered. Correlations between AREF scores and the other measures were performed to assess external construct validity. Performance differences between school groups on AREF subtests were analyzed using ANOVA, t-test, and Mann-Whitney tests, and the internal consistency of the instrument's tasks was evaluated using Cronbach's alpha coefficient. Results: The scores of the AREF subtests demonstrated significant positive correlations with reading measures (ranging from 0.339 to 0.367) and executive functions (ranging from 0.209 to 0.396). Significant differences were found in the performance of some AREF tasks when comparing individuals from public and private schools, as well as between 4th and 5th graders compared to students in higher grades. The internal consistency of the tasks was low for Graphophonological-Semantic Flexibility (Cronbach's α = 0.566), moderate for Inhibitory Control and Flexibility (Cronbach's α = 0.768), and high for Working Memory (Cronbach's α = 0.881). Discussion: The results provide initial evidence of construct validity and reliability for the AREF subtests. It is expected that this new neuropsychological test will contribute to the assessment of reading skills and executive functions, assisting in guiding clinical and educational interventions for individuals with and without neurodevelopmental disorders.

6.
Int J Pediatr Otorhinolaryngol ; 186: 112128, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39378540

RESUMO

INTRODUCTION: Auditory perception process is a transient phenomenon, which enables the person to make the relationship between events and auditory factor by working memory and obtain the sequence of auditory features and be able differentiate the auditory sources by using these component. In auditory processing, the basis formed by bottom - up process (data - driven). This pathway is dependent on the central auditory integration and also on acoustic signal input and interpreting auditory information is involved top-down process (concept - driven), which this pathway is dependent on central higher resource such as perception, attention, working memory and its span. The purpose of this study was to address information about top-down processing and auditory processing disorder. MATERIALS AND METHODS: A review of the latest literature on (central) auditory processing disorders and top-down processing was performed using PUBMED, EBSCO, SCIENCE DIRECT, ASHA, GOOGLE SCHOLAR, THIEME, PROQUEST data sources. CONCLUSION: Deficit in cognitive processing of auditory information in children cause difficulty in processing auditory information and outbreak auditory processing disorder symptoms. Cognitive evaluation (especially working memory) in this subject is important as bottom-up processing evaluation.

7.
Neuropsychologia ; : 109009, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39374857

RESUMO

Deficits in rhythm perception and production have been reported in a variety of psychiatric, neurodevelopmental and neurologic disorders. Since correlations between rhythmic abilities and cognitive functions have been demonstrated in neurotypical individuals, we here investigate whether and how rhythmic abilities are associated with cognitive functions in 35 participants with neurocognitive deficits due to acquired brain lesions. We systematically assessed a diverse set of rhythm perception and production abilities including time and beat perception and finger-tapping tasks. Neuropsychological tests were applied to assess separable cognitive functions. Using multiple regression analyses we show that lower variability in aligning movements to a pacing sequence was predicted by better inhibitory control and better working memory performance. Working memory performance also predicted lower variability of rhythmic movements in the absence of an external pacing sequence and better anticipatory timing to sequences with gradual tempo changes. Importantly, these predictors remained significant for all regression models when controlling for other cognitive variables (i.e., cognitive flexibility, information processing speed, and verbal learning ability) and potential confounders (i.e., age, symptom strength of depression, manual dexterity, duration of illness, severity of cognitive impairment, and musical experience). Thus, all rhythm production abilities were significantly predicted by measures of executive functions. In contrast, rhythm perception abilities (time perception / beat perception) were not predicted by executive functions in this study. Our results, enhancing the understanding of cognitive underpinnings of rhythmic abilities in individuals with neurocognitive deficits, may be a first mandatory step to further potential therapeutic implications of rhythm-based interventions in neuropsychological rehabilitation.

8.
Psychon Bull Rev ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39375301

RESUMO

Emotions are known to influence cognitive performance, particularly working memory (WM) in both its aspects, processing, and maintenance. One explanatory mechanism might be that negative stimuli capture attentional resources, leaving fewer resources for attentional maintenance and processing of information in WM. However, this attentional capture was only investigated using WM tasks in which participants were explicitly asked to process negative items. The aim of this paper was to determine whether explicit processing of emotional stimuli is necessary to impair WM performance, or if their mere presence is enough to capture attention. For this purpose, participants performed a complex span task in which they alternated between memorizing a series of neutral words and processing either emotional images or neutral ones. In Experiment 1, participants were instructed to explicitly process emotional images, whereas in Experiment 2, emotional images were presented without any processing being required. In both experiments, we observed a decrease in memory performance when the images were negative compared to neutral. Whether or not voluntary processing is involved, emotional images seem to capture attentional resources, which in turn leads to a decline in memory performance. These results were discussed in relation to attentional theories and the influence of emotion on the specific mechanisms of WM.

9.
J Exp Child Psychol ; 249: 106096, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39366297

RESUMO

Working memory (WM) refers to the ability to actively maintain and process information needed to complete complex tasks such as comprehension, learning, and reasoning. Recent studies have examined the efficacy of computerized working memory training (WMT) in improving cognitive functions in general and WM in particular, with mixed results. Thus, to what extent can WMT produce near and far transfer effects to cognitive function is currently unclear. This study investigated the transfer effects of a computerized WMT for preschool children and also examined the possible neural correlates using the event-related potential (ERP) technique. A total of 50 Chinese preschoolers (64.44 ± 7.76 months old; 24 girls) received 4-week training during school hours. Compared with those in the active control group, children in the training group showed better gains in behavioral performance in the WM task and significantly more changes in ERP markers of the WM and inhibitory control tasks (near transfer effect). However, no evidence was found for transfer to fluid intelligence (far transfer effect). These findings suggest that WMT is capable of enhancing cognitive functioning in preschool children, and as such this work has important implications for educational practice and it may help to design and refine cognitive interventions for typically developing children and those with WM problems or other cognitive deficits (e.g., children with attention-deficit/hyperactivity disorder).

10.
Front Psychiatry ; 15: 1428425, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39371911

RESUMO

Background: Major depressive disorder (MDD) is associated with deficits in cognitive function, thought to be related to underlying decreased hedonic experiences. Further research is needed to fully elucidate the role of functional brain activity in this relationship. In this study, we investigated the neurofunctional correlate of the interplay between cognitive function and hedonic experiences in medication-free MDD using functional near-infrared spectroscopy (fNIRS). Methods: We examine differences of brain activation corresponding to the verbal fluency test (VFT) between MDD patients and healthy controls (HCs). Fifty-six MDD patients and 35 HCs underwent fMRI scanning while performing the VFT. In exploratory analyses, cognitive performance, as assessed by the Cambridge Neuropsychological Test Automated Battery (CANTAB), four dimensions of hedonic processing (desire, motivation, effort, and consummatory pleasure) measured by the Dimensional Anhedonia Rating Scale (DARS), and relative changes in oxygenated hemoglobin concentration during the VFT were compared across groups. Results: Patients with MDD demonstrated impairments in sustained attention and working memory, accompanied by lower total and subscale scores on the DARS. Compared to healthy controls, MDD patients exhibited reduced activation in the prefrontal cortex (PFC) during the VFT task (t = 2.32 to 4.77, p < 0.001 to 0.02, FDR corrected). DARS motivation, desire, and total scores as well as sustained attention, were positively correlated with activation in the dorsolateral PFC and Broca's area (p < 0.05, FDR corrected). Conclusions: These findings indicate that changes in prefrontal lobe oxygenated hemoglobin levels, a region implicated in hedonic motivation and cognitive function, may serve as potential biomarkers for interventions targeting individuals with MDD. Our results corroborate the clinical consensus that the prefrontal cortex is a primary target for non-invasive neuromodulatory treatments for depression.

11.
J Cogn ; 7(1): 70, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39372099

RESUMO

The inhibition of return effect in perception refers to the observation that one is slower to re-attend a location that was attended right before, compared to a location that was not attended right before. Johnson et al. (2013, Psych. Sc., 24, 1104-1112, doi:10.1177/0956797612466414) observed a similar inhibitory effect for an attended item in working memory, which the authors referred to as an inhibition-of-return-like effect. However, testing an inhibition of return effect requires attention to be disengaged from the attended item, before testing whether participants are slower to return to said item. This was assumed but not experimentally manipulated in the paradigm by Johnson and colleagues. In the current study, we investigated whether an inhibition of return effect can be observed in working memory when attention is experimentally disengaged from the attended item before measuring whether responses are slower for the item in question. Participants were indeed slower to respond to a memory probe that matched the item that was attended right before, compared to a memory probe that matched the item that was not attended right before. Thus, our test with more experimental control did result in an inhibition of return effect in working memory.

12.
Front Psychol ; 15: 1389604, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39364089

RESUMO

Current theories suggest that visual and spatial processes in working memory are crucial for learning from animation. However, despite over three decades of research on learning from animation, little is known about how visuospatial working memory relates to learning. Instead, animation research often relies on subjective task load to explain and predict learning performance. To better understand how visuospatial working memory and learning from animation are related, a within-subjects study was conducted. Eighty six students learned from two animations of different complexity. The students' performance on visual learning tasks, visual and spatial working memory capacity, and perceived task load were assessed. Hierarchical regression analyses show that visuospatial working memory capacity is more critical for learning from a complex animation than for learning from a less complex animation. Moreover, visuospatial working memory capacity predicts learning from a complex animation significantly better than subjective task load. The effect size is large. The results provide a coherent picture of the relationships between learning task demands, learners' visuospatial working memory, perceived task load and learning performance. They not only allow for a more accurate prediction of learning from animation but can also help to tailor the design and use of animations to the learners' cognitive resources.

13.
Artigo em Inglês | MEDLINE | ID: mdl-39367567

RESUMO

CONTEXT: Limited data provides evidence-based insights on the association between comprehensive metrics of high-density lipoproteins (HDL) and cognitive performance, especially in midlife women for whom benefit might be the greatest. OBJECTIVE: To assess the associations of serum HDL metrics including HDL lipid content [HDL cholesterol, phospholipid (HDL-PL), triglyceride], proteins/subclasses [apolipoprotein A-1 (apoA-1); small, medium, large, total HDL particle (HDL-P); and HDL size], and cholesterol efflux capacity with cognitive performance in midlife women. METHODS: This prospective cohort study was conducted among 503 midlife women (1234 observations) from the Study of Women's Health Across the Nation HDL ancillary study. Joint models were applied to examine associations of HDL metrics assessed at midlife (50.2 ± 2.9 years, baseline of the current study) and their changes over midlife (6.1 ± 3.9 years of duration) with subsequent cognitive performance [working memory (Digit Span Backward Test), processing speed (Symbol Digit Modalities Test), and episodic memory immediate and delayed recall (East Boston memory test)] assessed repeatedly (maximum 5 times) 1.5 ± 1 years later over 7.72 ± 4.10 years of follow up. RESULTS: Higher total HDL-P and smaller HDL size at midlife were associated with a better subsequent immediate recall, delayed recall and/or processing speed. Greater increase in HDL-PL, apoA-1, medium HDL-P, and total HDL-P and less increase in HDL size over midlife were associated with a better subsequent immediate and/or delayed recall. CONCLUSIONS: Enhancing specific serum HDL metrics during midlife could be promising in cognitive restoration, particularly memory, the initial and predominant symptom of Alzheimer's disease.

14.
Alzheimers Dement ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39382098

RESUMO

INTRODUCTION: Early detection of both objective and subjective cognitive impairment is important. Subjective complaints in healthy individuals can precede objective deficits. However, the differential associations of objective and subjective cognition with modifiable dementia risk factors are unclear. METHODS: We gathered a large cross-sectional sample (N = 3327, age 18 to 84) via a smartphone app and quantified the associations of 13 risk factors with subjective memory problems and three objective measures of executive function (visual working memory, cognitive flexibility, model-based planning). RESULTS: Depression, socioeconomic status, hearing handicap, loneliness, education, smoking, tinnitus, little exercise, small social network, stroke, diabetes, and hypertension were all associated with impairments in at least one cognitive measure. Subjective memory had the strongest link to most factors; these associations persisted after controlling for depression. Age mostly did not moderate these associations. DISCUSSION: Subjective cognition was more sensitive to self-report risk factors than objective cognition. Smartphones could facilitate detecting the earliest cognitive impairments. HIGHLIGHTS: Smartphone assessments of cognition were sensitive to dementia risk factors. Subjective cognition had stronger links to most factors than did objective cognition. These associations were not fully explained by depression. These associations were largely consistent across the lifespan.

15.
Wiley Interdiscip Rev Cogn Sci ; : e1696, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379174

RESUMO

Working memory is thought to be the psychological capacity that enables us to maintain or manipulate information no longer in our environment for goal-directed action. Recent work argues that working memory is not a so-called natural kind and in turn cannot explain the cognitive processes attributed to it. This paper first clarifies the scope of this earlier critique and argues for a pluralist account of working memory. Under this account, working memory is variously realized by many mechanisms that contribute to the maintenance and manipulation of information across tasks. This view in effect updates one of the earliest pluralist formulations of working memory. Juxtaposing this view against deflationary descriptions allows us to delineate two gradients that help us chart various accounts of working memory and identify their respective theoretical commitments. In turn, we can isolate those accounts that fail to accord with the evidence supporting a pluralist view, and we can begin to rehabilitate working memory as a pluralist, and ultimately more informative, construct.

16.
Artigo em Inglês | MEDLINE | ID: mdl-39379769

RESUMO

Previous behavioral research has found that working memory is associated with emotion regulation efficacy. However, there has been mixed evidence as to whether the neural mechanisms between emotion regulation and working memory overlap. The present study tested the prediction that individual differences on the working memory subtest of the Weschler Adult Intelligence Scale (WAIS-IV) could be predicted from the pattern of brain activity produced during emotion regulation in regions typically associated with working memory, such as the dorsal lateral prefrontal cortex (dlPFC). A total of 101 participants completed an emotion regulation fMRI task in which they either viewed or reappraised negative images. Participants also completed working memory test outside the scanner. A whole brain covariate analysis contrasting the reappraise negative and view negative BOLD response found that activity in the right dlPFC positively related to working memory ability. Moreover, a multivoxel pattern analysis approach using tenfold cross-validated support vector regression in regions-of-interest associated with working memory, including bilateral dlPFC, demonstrated that we could predict individual differences in working memory ability from the pattern of activity associated with emotion regulation. These findings support the idea that emotion regulation shares underlying cognitive processes and neural mechanisms with working memory, particularly in the dlPFC.

17.
Psychon Bull Rev ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390302

RESUMO

Based on the hypothesis of two maintenance mechanisms of verbal information in working memory, an articulatory loop and an attentional executive loop, Barrouillet et al. predicted and observed that facilitating the optimal use and separation of these two systems results in a strong increase in recall performance. They developed for this purpose the maxispan procedure, in which participants cumulatively rehearse aloud a limited number of the first items of the series (i.e., three or four) and keep rehearsing them until the end of the series before recall. Beyond increasing recall performance, the model also predicts that the maxispan procedure should also abolish the phonological similarity effect (PSE, the poorer recall of phonologically similar than dissimilar items) in both the rehearsed and the nonrehearsed items by permitting the perfect maintenance of the former in a nonoverloaded articulatory loop and preventing storage of phonological traces of the latter in the attentional system. However, the PSE should reappear if too many items are verbally rehearsed in the maxispan procedure. In this case, the overload of the articulatory loop should lead to offload its content into the attentional system where phonologically similar traces are prone to confusion. We tested and verified these hypotheses in two experiments.

18.
Front Aging Neurosci ; 16: 1433551, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39385828

RESUMO

Objective: This study aimed to investigate cortical activation and functional connectivity in the cortex during working memory (WM) tasks in patients with Alzheimer's disease (AD) using functional near-infrared spectroscopy (fNIRS). Methods: A total of 17 older adults with AD and 17 cognitively normal (CN) participants were recruited. fNIRS was utilized to monitor oxygenated hemoglobin (HbO) concentrations in the frontotemporal lobe, while participants performed WM tasks to examine WM impairments in subjects with AD. Student's t-test for continuous variables and the chi-square test for categorical variables were used to compare the clinical and HbO variables between the AD and CN groups. Functional connectivity was analyzed using Pearson's correlation coefficient between the time series of each channel-to-channel pair. Results: The changes in HbO concentrations and cortical activations during the WM task showed that the HbO concentration curve of the CN group was higher than that of the AD group during the encoding and maintenance phases of the WM task. Although in the brain region scale, there were no significant differences in average HbO concentrations between the two groups, many channels located in the frontal and temporal lobes showed significant differences (p < 0.05) in the average HbO (channels 7 and 32) and slope HbO values (channels 7, 8, 9, 23, 30, 34, and 38) during the WM task. The average functional connectivity of the AD group was significantly lower than that of the CN group (p < 0.05). The functional connectivity was stronger in the frontopolar (FP) region than in other areas in both groups. Conclusion: This study revealed there were significant differences in HbO concentration in older adult patients with AD compared to CN during the WM task. The characteristics of HbO measured by the fNIRS technique can be valuable for distinguishing between AD and CN in older adults.

19.
Mem Cognit ; 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39384731

RESUMO

Visual working memory (VWM) plays a crucial role in temporarily storing and processing visual information, but the nature of stored representations and their interaction with new inputs has long been unclear. The pointer system refers to how VWM links new sensory inputs to stored information using specific cues. This study aimed to investigate whether the pointer system is based on spatial, feature-based, or object-based cues by employing the repetition benefit effect, where memory performance improves with repeated memory items. Across three experiments, we manipulated spatial positions, shapes, and colors as pointer cues to determine how these features affect VWM consolidation and updating. The results showed that while spatial location serves as a strong pointer cue, shape and color features can also effectively reestablish object correspondence in VWM. These findings support the view that the pointer system in VWM is flexible and object-based, utilizing various feature cues to maintain memory continuity. This study provides new insights into how VWM connects new inputs with stored information through the pointer system.

20.
Front Psychol ; 15: 1346896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39380755

RESUMO

Objective: This study was to investigate the developmental characteristics of executive function (EF) in obese adolescents and the time-course effects of a 14-week exercise intervention combining aerobic exercise and resistance training on EF in this population. Methods: The experimental group of 28 obese junior high school students participated in the exercise intervention combining aerobic exercise and resistance training, while the control group of 24 healthy weight junior high school students engaged in the regular recess exercise. EF, including inhibition, working memory, and cognitive flexibility, was assessed 1 week prior to the exercise intervention and at 12 and 14 weeks post-intervention. Changes in EF sub-functions in both groups at different time points during the exercise intervention were analyzed. Results: The findings revealed that obese junior high school students exhibited lower levels of inhibition (p = 0.003, Cohen's d = 0.848) and cognitive flexibility (p = 0.013, Cohen's d = 0.706) compared to their healthy weight peers. The exercise intervention combining aerobic exercise and resistance training led to significant improvements in EF among obese junior high school students, with inhibition (p < 0.01, Cohen's d = 0.713; p = 0.003, Cohen's d = 0.683) and cognitive flexibility (p = 0.001, Cohen's d = 0.797; p < 0.01, Cohen's d = 0.890) showing significant improvement at 12 and 14 weeks post-intervention, and working memory demonstrating significant improvement at 14 weeks (p = 0.004, Cohen's d = 0.710). No significant differences were observed in EF over time in healthy weight junior high school students. Conclusion: Obese adolescents had impaired EF, as evidenced by low levels of the inhibition and cognitive flexibility compared to healthy weight adolescents. The exercise intervention combining aerobic exercise and resistance training had a positive effect on EF of obese adolescents. The time-course effects of the intervention on improvements in inhibition, working memory, and cognitive flexibility varied with intervention duration in obese adolescents, with significant changes in inhibition and cognitive flexibility observed at 12 weeks and significant changes in working memory at 14 weeks.

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