scholarly journals Effects of tDCS Dosage on Working Memory in Healthy Participants

2017 ◽  
Author(s):  
Stevan Nikolin ◽  
Donel Martin ◽  
Colleen K. Loo ◽  
Tjeerd W. Boonstra
Keyword(s):  
Working Memory ◽  
Response Time ◽  
Effect Size ◽  
Biological Effects ◽  
Parallel Group Design ◽  
Parallel Group ◽  
P3 Amplitude ◽  
Time Accuracy ◽  
Study Designs ◽  
Healthy Participants

AbstractBackgroundTranscranial direct current stimulation (tDCS) has been found to improve working memory (WM) performance in healthy participants following a single session. However, results are mixed and the overall effect size is small. Interpretation of these results is confounded by heterogeneous study designs, including differences in tDCS dose (current intensity) and sham conditions used.AimsWe systematically investigated the effect of tDCS dose on working memory using behavioural and neurophysiological outcomes.MethodsIn a single-blind parallel group design, 100 participants were randomised across five groups to receive 15 minutes of bifrontal tDCS at different current intensities (2mA, 1mA, and three sham tDCS conditions at 0.034mA, 0.016mA, or 0mA). EEG activity was acquired while participants performed a WM task prior to, during, and following tDCS. Response time, accuracy and an event-related EEG component (P3) were evaluated.ResultsWe found no significant differences in response time or performance accuracy between current intensities. The P3 amplitude was significantly lower in the 0mA condition compared to the 0.034mA, 1mA and 2mA tDCS conditions. Changes in WM accuracy were moderately correlated with changes in the P3 amplitude following tDCS compared to baseline levels (r = 0.34).ConclusionsWorking memory was not significantly altered by tDCS, regardless of dose. The P3 amplitude showed that stimulation at 1mA, 2mA and a sham condition (0.034mA) had biological effects, with the largest effect size for 1mA stimulation. These findings indicate higher sensitivity of neurophysiological outcomes to tDCS and suggests that sham stimulation previously considered inactive may alter neuronal function.

scholarly journals Transdiagnostic comparison of visual working memory capacity in bipolar disorder and schizophrenia

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Catherine V. Barnes-Scheufler ◽  
Caroline Passow ◽  
Lara Rösler ◽  
Jutta S. Mayer ◽  
Viola Oertel ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Working Memory ◽  
Visual Working Memory ◽  
Effect Size ◽  
Working Memory Capacity ◽  
Memory Capacity ◽  
Medium Effect ◽  
Full Spectrum ◽  
Small Effect Size ◽  
The Difference

Abstract Background Impaired working memory is a core cognitive deficit in both bipolar disorder and schizophrenia. Its study might yield crucial insights into the underpinnings of both disorders on the cognitive and neurophysiological level. Visual working memory capacity is a particularly promising construct for such translational studies. However, it has not yet been investigated across the full spectrum of both disorders. The aim of our study was to compare the degree of reductions of visual working memory capacity in patients with bipolar disorder (PBD) and patients with schizophrenia (PSZ) using a paradigm well established in cognitive neuroscience. Methods 62 PBD, 64 PSZ, and 70 healthy controls (HC) completed a canonical visual change detection task. Participants had to encode the color of four circles and indicate after a short delay whether the color of one of the circles had changed or not. We estimated working memory capacity using Pashler’s K. Results Working memory capacity was significantly reduced in both PBD and PSZ compared to HC. We observed a small effect size (r = .202) for the difference between HC and PBD and a medium effect size (r = .370) for the difference between HC and PSZ. Working memory capacity in PSZ was also significantly reduced compared to PBD with a small effect size (r = .201). Thus, PBD showed an intermediate level of impairment. Conclusions These findings provide evidence for a gradient of reduced working memory capacity in bipolar disorder and schizophrenia, with PSZ showing the strongest degree of impairment. This underscores the importance of disturbed information processing for both bipolar disorder and schizophrenia. Our results are compatible with the cognitive manifestation of a neurodevelopmental gradient affecting bipolar disorder to a lesser degree than schizophrenia. They also highlight the relevance of visual working memory capacity for the development of both behavior- and brain-based transdiagnostic biomarkers.

Effect of shift work on working memory, attention and response time in nurses

2020 ◽  
pp. 1-19
Author(s):  
Azam Esmaily ◽  
Sara Jambarsang ◽  
Farough Mohammadian ◽  
Amir Houshang Mehrparvar
Keyword(s):  
Working Memory ◽  
Response Time ◽  
Shift Work

scholarly journals A multi-component, adaptive Working Memory Assessment Battery (WoMAB): validation and norms in an Italian population sample

2021 ◽  
Author(s):  
Fabrizio Pasotti ◽  
Giulia De Luca ◽  
Edoardo Nicolò Aiello ◽  
Chiara Gramegna ◽  
Marco Di Gangi ◽  
...  
Keyword(s):  
Working Memory ◽  
Neurological Disorders ◽  
Digit Span ◽  
Population Sample ◽  
Italian Population ◽  
Everyday Functioning ◽  
Assessment Battery ◽  
Memory Assessment ◽  
Test Digit ◽  
Healthy Participants

Abstract Background Working memory (WM) abilities are frequently impaired in neurological disorders affecting fronto-parietal cortical/sub-cortical structures. WM deficits negatively influence interventional outcomes and everyday functioning. This study thus aimed at the following: (a) developing and standardizing an ecologically valid task for WM assessment ( Ice Cream Test, ICT); (b) validating and norming a novel WM test (Digit Ordering Test, DOT), as well as providing updated norms for digit span (DS) tasks, in an Italian population sample; (c) introducing a novel scoring procedure for measuring WM. Methods One-hundred and sixty-eight Italian healthy participants—73 male, 95 females; age: 48.4 ± 19.1 (18–86); education: 12.1 ± 4.8 (4–21)—underwent a thorough WM assessment—DOT, ICT, and both forward and backward DS tasks (FDS, BDS). The ICT requires participants to act as waiters who have to keep track of customers’ orders. For each task, WM and total (T) outcomes were computed, i.e., the number of elements in the longest sequence and that of recalled sequences, respectively. Norms were derived via the equivalent score (ES) method. Results DS ratios (DSRs) were computed for both WM/S and T outcomes on raw DS measures (BDS divided by FDS). Age and education significantly predicted all WM tasks; sex affected FDS and DSR-T scores (males > females). WM measures were highly internally related. Discussion The present work provides Italian practitioners with a normatively updated, multi-component, adaptive battery for WM assessment (WoMAB) as well as with novel outcomes which capture different WM facets—WM capacity and attentive monitoring abilities.

The effect of caloric restriction on working memory in healthy non-obese adults

CNS Spectrums ◽  
2019 ◽  
Vol 25 (1) ◽  
pp. 2-8 ◽  
Author(s):  
Emilie Leclerc ◽  
Alisson Paulino Trevizol ◽  
Ruth B. Grigolon ◽  
Mehala Subramaniapillai ◽  
Roger S. McIntyre ◽  
...  
Keyword(s):  
Working Memory ◽  
Energy Expenditure ◽  
Sleep Quality ◽  
Caloric Restriction ◽  
Neuropsychological Tests ◽  
Spatial Working Memory ◽  
Multicenter Trial ◽  
Obese Adults ◽  
Parallel Group ◽  
Lower Protein

Objective.We aim to evaluate the effect of caloric restriction (CR) in cognition by comparing performance in neuropsychological tests for working memory between a group of non-obese healthy subjects doing CR for 2 years with another consuming ad libitum diet (AL).Methods.This study was part of a larger multicenter trial called CALERIE that consisted of a randomized clinical trial with parallel-group comparing 2 years of 25% CR and AL in 220 volunteers with a BMI between 22 and 28 kg/m2, across 3 sites. The cognitive tests used were the Cambridge Neuropsychological Tests Automated Battery (CANTAB) for Spatial Working Memory (SWM) including the total number of errors (SWMTE) and strategy (SWMS). Included as possible moderators were sleep quality, mood states, perceived stress, and energy expenditure. Analyses were performed at baseline and months 12 and 24.Results.After adjustments, there was a significantly greater improvement in working memory assessed by the SWM for CR individuals, compared to AL. At month 24, it was related mostly to lower protein intake, compared to other macronutrients. Changes in SWM were moderated by changes in sleep quality, physical activity, and energy expenditure.Conclusion.On the long term, CR in healthy individuals seems to have a slightly positive effect on working memory. The study of brain CR targets opens new possibilities to prevent and treat cognitive deficits.

New data on the use of lithium, divalproate, and lamotrigine in rapid cycling bipolar disorder

2005 ◽  
Vol 20 (2) ◽  
pp. 92-95 ◽  
Author(s):  
JR Calabrese ◽  
DJ Rapport ◽  
EA Youngstrom ◽  
K. Jackson ◽  
S. Bilali ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Unmet Need ◽  
Depressive Illness ◽  
Term Treatment ◽  
Rapid Cycling ◽  
Double Blind ◽  
Parallel Group Design ◽  
Parallel Group ◽  
Long Term Treatment ◽  
Current Therapies

AbstractThe rapid cycling variant of bipolar disorder is defined as the occurrence of four periods of either manic or depressive illness within 12 months. Patients suffering from this variant of bipolar disorder have an unmet need for effective treatment. This review examines two major studies in an attempt to update understanding of the current therapies available to treat rapid cycling patients. The first trial compares lamotrigine versus placebo in 182 patients studied for 6 months. The second is a recently completed, 20-month trial comparing divalproate and lithium in 60 patients. Both trials had a double-blind, randomized parallel-group design. The data from the latter study indicate that there are no large differences in efficacy between lithium and divalproate in the long-term treatment of rapid cycling bipolar disorder. In addition, lamotrigine has the potential to complement the spectrum of lithium and divalproate through its greater efficacy for depressive symptoms.

A Clinical Study of Quazepam in Hospitalized Patients with Insomnia

1981 ◽  
Vol 9 (4) ◽  
pp. 288-291 ◽  
Author(s):  
Hans K Uhthoff ◽  
Jacques A Brunet ◽  
Anand Aggerwal ◽  
Raymond Varin
Keyword(s):  
Clinical Study ◽  
Sleep Quality ◽  
Quality Index ◽  
Adverse Reactions ◽  
Activity Index ◽  
Global Evaluation ◽  
Group Design ◽  
Parallel Group Design ◽  
Parallel Group ◽  
Hypnotic Activity

The efficacy of quazepam (Sch-16134) 15 mg capsules as a hypnotic has been compared with that of placebo in a 9-day study, using a parallel-group design. The physician's global evaluation numerically favoured quazepam 63% (nineteen of thirty) over placebo 50% (fifteen of thirty). Furthermore, it demonstrated greater improvement in Hypnotic Activity Index and Sleep Quality Index from baseline scores, and caused no adverse reactions.

scholarly journals Working memory and intra-individual variability in response time mediate fluid intelligence deficits associated with ADHD symptoms

2017 ◽  
Author(s):  
Christopher Brydges ◽  
Krista Ozolnieks ◽  
Gareth Roberts
Keyword(s):  
Working Memory ◽  
Response Time ◽  
Fluid Intelligence ◽  
Individual Variability ◽  
Self Report ◽  
Adhd Symptoms ◽  
Memory Response ◽  
Hyperactivity Disorder ◽  
Inattention And Hyperactivity ◽  
Response Consistency

Attention-deficit/hyperactivity disorder (ADHD) is a neuropsychologicalcondition characterised by inattention and hyperactivity. Cognitive deficits are commonly observed in ADHD patients, including impaired working memory, response consistency, and fluid intelligence, which are theorised to be associated with one another. We aimed to determine if decreased fluid intelligence was associated with ADHD, and was mediated by deficits in working memory and intra-individual variability (IIV) in motor responding. The present study tested 142 young adults from the general population on a range of working memory, response time, and fluid intelligence tasks, and an ADHD self-report symptoms questionnaire. Results showed that total and hyperactive ADHD symptoms correlated significantly and negatively with fluid intelligence, but this association was fully mediated by both working memory and IIV in response time. However, inattentive symptoms were not associated with fluid intelligence. These results have important implications for clinicians using speeded psychometric tests as part of their assessment battery.

scholarly journals Within-person variability in men’s facial width-to-height ratio

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e1801 ◽  
Author(s):  
Robin S.S. Kramer
Keyword(s):  
Facial Expressions ◽  
Effect Size ◽  
Focal Length ◽  
Effect Sizes ◽  
Emotional Expressions ◽  
Head Pose ◽  
Height Ratio ◽  
Camera Parameters ◽  
Study Designs ◽  
The Relationship

Background.In recent years, researchers have investigated the relationship between facial width-to-height ratio (FWHR) and a variety of threat and dominance behaviours. The majority of methods involved measuring FWHR from 2D photographs of faces. However, individuals can vary dramatically in their appearance across images, which poses an obvious problem for reliable FWHR measurement.Methods.I compared the effect sizes due to the differences between images taken with unconstrained camera parameters (Studies 1 and 2) or varied facial expressions (Study 3) to the effect size due to identity, i.e., the differences between people. In Study 1, images of Hollywood actors were collected from film screenshots, providing the least amount of experimental control. In Study 2, controlled photographs, which only varied in focal length and distance to camera, were analysed. In Study 3, images of different facial expressions, taken in controlled conditions, were measured.Results.Analyses revealed that simply varying the focal length and distance between the camera and face had a relatively small effect on FWHR, and therefore may prove less of a problem if uncontrolled in study designs. In contrast, when all camera parameters (including the camera itself) are allowed to vary, the effect size due to identity was greater than the effect of image selection, but the ranking of the identities was significantly altered by the particular image used. Finally, I found significant changes to FWHR when people posed with four of seven emotional expressions in comparison with neutral, and the effect size due to expression was larger than differences due to identity.Discussion.The results of these three studies demonstrate that even when head pose is limited to forward facing, changes to the camera parameters and a person’s facial expression have sizable effects on FWHR measurement. Therefore, analysing images that fail to constrain some of these variables can lead to noisy and unreliable results, but also relationships caused by previously unconsidered confounds.

Association Between the Visual N1-P2 Complex and Neuroticism

2021 ◽  
pp. 155005942110399
Author(s):  
Bowen Xiu ◽  
Christopher Andanty ◽  
Nasia Dai ◽  
Clement C. Zai ◽  
Ariel Graff ◽  
...  
Keyword(s):  
Working Memory ◽  
Error Detection ◽  
Memory Task ◽  
Event Related Potentials ◽  
Related Potentials ◽  
Significant Performance ◽  
Impaired Attention ◽  
Electroencephalographic Activity ◽  
Healthy Participants ◽  
P200 Amplitude

Neuroticism is a personality trait associated with impaired attention, memory, and error detection. Thus, the present study investigated the visual N100 and P200 event-related potentials components associated with attention using a 2-back working memory task in healthy neurotic and nonneurotic participants, evaluated using the Neuroticism, Extraversion, Openness Five Factor Inventory. A total of 35 healthy participants were asked to perform the 2-back task while recording electroencephalographic activity from 64 electrodes on the scalp. Analysis of the N100 and P200 amplitude and latency in high neuroticism and low neuroticism subjects showed an increased P200 amplitude and latency for high neuroticism subjects in the frontal and parietal regions, respectively. However, there were no significant performance differences between the high and low neuroticism subjects for the 2-back working memory task. Therefore, the results suggest that neuroticism is associated with the P200 component elicited in the context of a working memory task.

scholarly journals Improving Attitudes to Volunteering Among Older Adults: A Randomized Trial Approach

2019 ◽  
Vol 42 (2) ◽  
pp. 51-61 ◽  
Author(s):  
Michelle I. Jongenelis ◽  
Ben Jackson ◽  
Jeni Warburton ◽  
Robert U. Newton ◽  
Simone Pettigrew
Keyword(s):  
Older Adults ◽  
Social Connectedness ◽  
Healthy Aging ◽  
Social Needs ◽  
Volunteer Work ◽  
Group Design ◽  
Perceptions And Attitudes ◽  
Parallel Group Design ◽  
Parallel Group ◽  
Negative Perceptions

Promoting engagement in formal volunteering represents a potential means of facilitating healthy aging. Given reluctance to participate in volunteering has been partially attributed to negative perceptions of various aspects of this activity, this study assessed whether trialing volunteering can improve perceptions among older people. Using a parallel-group design, Australians aged 60+ years ( n = 445) were randomly assigned to one of two conditions, one in which they were encouraged to trial volunteering and one in which they were asked to continue their usual activities. Perceptions and attitudes among those in the volunteering condition became significantly more favorable over 6 months relative to those in the control condition, with this change predicted by several aspects of the volunteering experience (e.g., acquisition of skills, increased social connectedness). Providing access to roles that cater to the learning and social needs of older adults appears to be important for improving attitudes toward engaging in volunteer work.

Sign in / Sign up

Export Citation Format

Share Document