Verbal Task Research Articles

Using the online version of the Trier Social Stress Test to investigate the effect of acute stress on functional lateralization

How stress affects functional hemispheric asymmetries is relevant because stress represents a risk factor for the development of mental disorders and various mental disorders are associated with atypical lateralization. Using three lateralization tasks, we investigated whether functional hemispheric asymmetries in the form of hemispheric dominance for language (verbal dichotic listening task), emotion processing (emotional dichotic listening task), and visuo-spatial attention (line bisection task) were affected by acute stress in healthy adults. One hundred twenty right-handed men and women performed these lateralization tasks in randomized order after exposure to a mild online stressor (i.e., an online variant of the Trier Social Stress Test (TSST), TSST-OL) and a non-stressful online control task (friendly TSST-OL, fTSST-OL) in a within-subjects design. Importantly, the verbal and the emotional dichotic listening tasks were presented online whereas the line bisection task was completed in paper–pencil form. During these tasks, we found the expected hemispheric asymmetries, indicating that online versions of both the verbal and the emotional dichotic listening task can be used to measure functional hemispheric asymmetries in language and emotion processing remotely. Even though subjective and physiological markers confirmed the success of the online stress manipulation, replicating previous studies, we found no stress-induced effect on functional hemispheric asymmetries. Thus, in healthy participants, functional hemispheric asymmetries do not seem to change flexibly in response to acute stress.

Navigating the mind's eye: Understanding gaze shifts in visuospatial bootstrapping.

Visuospatial bootstrapping refers to the well-replicated phenomena in which serial recall in a purely verbal task is boosted by presenting digits within the familiar spatial layout of a typical telephone keypad. The visuospatial bootstrapping phenomena indicates that additional support comes from long-term knowledge of a fixed spatial pattern, and prior experimentation supports the idea that access to this benefit depends on the availability of the visuospatial motor system. We investigate this by tracking participants' eye movements during encoding and retention of verbal lists to learn whether gaze patterns support verbal memory differently when verbal information is presented in the familiar visual layout. Participants' gaze was recorded during attempts to recall lists of seven digits in three formats: centre of the screen, typical telephone keypad, or a spatially identical layout with randomised number placement. Performance was better with the typical than with the novel layout. Our data show that eye movements differ when encoding and retaining verbal information that has a familiar layout compared with the same verbal information presented in a novel layout, suggesting recruitment of different spatial rehearsal strategies. However, no clear link between gaze pattern and recall accuracy was observed, which suggests that gazes play a limited role in retention, at best.

Differential Effects of Continuous Theta Burst Stimulation over the Bilateral and Unilateral Cerebellum on Working Memory.

Recent functional MRI studies have implicated the cerebellum in working memory (WM) alongside the prefrontal cortex. Some findings indicate that the right cerebellum is activated during verbal tasks, while the left is engaged during visuospatial tasks, suggesting cerebellar lateralization in WM function. The cerebellum could be a potential target for non-invasive brain stimulation (NIBS) to enhance WM function in cognitive disorders. However, the comprehensive influence of cerebellar lateralization on different types of WM and the effect of stimulation over the unilateral or bilateral cerebellum remain uncertain. This study was to investigate the cerebellum's functional lateralization and its specific impact on various aspects of WM in a causal manner using unilateral or bilateral cerebellar continuous theta burst stimulation (cTBS), a form of inhibitroy NIBS. Twenty-four healthy participants underwent four sessions of cTBS targeting the left, right, or bilateral Crus I of the cerebellum, or a sham condition, in a controlled cross-over design. WM performance was assessed pre- and post-stimulation using neuropsychological tests, including the 3-back task, spatial WM task, and digit span task. Results indicated that cTBS over the bilateral and right cerebellum both led to a greater improvement in 3-back task performance compared to sham stimulation. Additionally, active cTBS over the bilateral cerebellum yielded better performance in the spatial WM task than sham stimulation. However, no significant differences were observed between stimulation conditions for the auditory digit span task. This study may provide novel causal evidence highlighting the specific involvement of the right and bilateral cerebellum in various types of WM. Specifically, the right cerebellum appears crucial for updating and tracking 3-back WM content, while spatial WM processes require the coordinated engagement of both cerebellar hemispheres.

Multisensory training based on an APP for enhanced verbal working memory in older adults

With the increasing aging population, contemporary society faces the imperative to develop approaches that efficiently delay the age-related decline in working memory capacity, which is a critical area within cognitive aging research. Nevertheless, there is insufficient evidence to support the efficacy of verbal working memory training across various sensory modalities (visual, auditory, and audiovisual) in enhancing the verbal working memory capacity of older adults. In this study, 60 healthy older adults (mean age = 67.07 ± 3.79 years, comprising 34 women and 26 men, mean education = 15.55 ± 2.53 years) were randomly assigned to one of four groups: visual verbal working memory (V-VWM) group, auditory verbal working memory (A-VWM) group, visual-auditory verbal working memory (VA-VWM) group, and a control group. The training duration spanned 12 days. We also investigated whether baseline level and education predicted the outcomes. Findings indicated that V-VWM training had a large effect on improving V-VWM task performance (Cohen's d = 1.765), A-VWM training showed a substantial effect on A-VWM task performance (Cohen's d = 1.904), and VA-VWM training demonstrated a significant effect on VA-VWM task performance (Cohen's d = 2.319) over pretest scores in older adults. Enhancements achieved through V-VWM training exhibited near transfer effects, improving performance in both A-VWM and VA-VWM tasks. In contrast, gains from A-VWM training were selectively transferred to the VA-VWM task. Furthermore, VA-VWM training led to improvements not only in V-VWM and A-VWM tasks but also extended to verbal operation span task with a significant 29.7 % increase. However, no significant transfer effects were observed for the DSF and DSB tasks across the three training groups. The maintenance effect of VA-VWM training persisted for two weeks across tasks involving VA-VWM, V-VWM, and A-VWM. The baseline of VWM span score influence the effect of V-VWM training and transfer effect of VA-VWM training. Education level did not predict the training effects of V-VWM, A-VWM, and VA-VWM. These findings highlight the nuanced effects of sensory-specific verbal working memory training in older adults, emphasizing the potential of tailored interventions to enhance specific aspects of cognitive function, while also highlighting the promising applications of mobile device training in enhancing cognitive skills among the elderly.

Executive functions in children with developmental language disorder: a systematic review and meta-analysis.

The purpose of the current study was to assess the differences between children with developmental language disorder (DLD) and typically developing (TD) children in their performance of executive functions from working memory, inhibitory control, and cognitive flexibility. We performed a systematical search of PubMed, Embase, Cochrane, and Web of Science for case control studies (published in English between January 1, 1950, and October 11, 2023) comparing the differences in the performance of executive functions between DLD and TD children. Forty eligible studies were included in the present study (N = 3,168 participants). In comparison with TD children, DLD children exhibited significantly poorer performances in all six verbal working memory tasks (backward digit recall task, SMD -1.4321, 95% CI -2.2692 to -0.5950; listening recall task, SMD -1.4469, 95% CI -1.7737 to -1.1202; counting recall task, SMD -0.9192, 95% CI -1.4089 to -0.4295; digit recall task, SMD -1.2321, 95% CI -1.4397 to -1.0244; word list recall task, SMD -1.1375, 95% CI -1.5579 to -0.7171; non-word recall task, SMD -1.5355, 95% CI -1.8122 to -1.2589). However, regarding inhibitory control and cognitive flexibility, the differences between DLD and TD children depended on specific circumstances. In subgroup analyses of all verbal working memory tasks, DLD children presented notably lower performance than TD children in both the monolingual English and monolingual non-English groups, and in both the preschooler and school-aged groups. This study proves that verbal working memory deficits can be seen as a marker for children with DLD and are not affected by age or language type. https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=391070, CRD42023391070.

Brain mGlu5 Is Linked to Cognition and Cigarette Smoking but Does Not Differ From Control in Early Abstinence From Chronic Methamphetamine Use.

The group-I metabotropic glutamate receptor subtype 5 (mGlu5) has been implicated in methamphetamine exposure in animals and in human cognition. Because people with methamphetamine use disorder (MUD) exhibit cognitive deficits, we evaluated mGlu5 in people with MUD and controls and tested its association with cognitive performance. Positron emission tomography was performed to measure the total VT of [18F]FPEB, a radiotracer for mGlu5, in brains of participants with MUD (abstinent from methamphetamine for at least 2 weeks, N = 14) and a control group (N = 14). Drug use history questionnaires and tests of verbal learning, spatial working memory, and executive function were administered. Associations of VT with methamphetamine use, tobacco use, and cognitive performance were tested. MUD participants did not differ from controls in global or regional VT, and measures of methamphetamine use were not correlated with VT. VT was significantly higher globally in nonsmoking vs smoking participants (main effect, P = .0041). MUD participants showed nonsignificant weakness on the Rey Auditory Verbal Learning Task and the Stroop test vs controls (P = .08 and P = .13, respectively) with moderate to large effect sizes, and significantly underperformed controls on the Spatial Capacity Delayed Response Test (P = .015). Across groups, Rey Auditory Verbal Learning Task performance correlated with VT in the dorsolateral prefrontal cortex and superior frontal gyrus. Abstinent MUD patients show no evidence of mGlu5 downregulation in brain, but association of VT in dorsolateral prefrontal cortex with verbal learning suggests that medications that target mGlu5 may improve cognitive performance.

Distorted time perception in patients with neurocognitive impairment

BackgroundTime perception is known to be distorted in patients with neuropsychiatric disorders. Therefore, this study aims to investigate the correlation between cognitive decline and time distortion by examining time perception in participants with neurocognitive impairment (Alzheimer's disease [AD], vascular dementia [VD], and Parkinson's disease dementia [PDD]) compared to those with subjective cognitive impairment (SCI). MethodsOverall, 569 participants with cognitive decline complaints between 2013 and 2022 were investigated. Participants were subjected to a verbal estimation task, time production task, time comparison task, and neuropsychological assessments. ResultsTime perception abilities were distorted in patients with neurocognitive impairment compared to those with SCI. Despite similar educational backgrounds, the vascular cognitive impairment (VCI)/VD group demonstrated the lowest MMSE scores (22.4 ± 4.2, p-value <0.001) and larger time-estimation errors. Patients with VCI/VD significantly underestimated time in the 35-s (19.6 ± 12.6s) and 60-s (28.7 ± 19.9s) tasks. In the time production task, patients with VCI/VD produced shorter times in their 15-s (12.7 ± 4.3; p-value = 0.001), 30-s (23.6 ± 8.3; p value < 0.001), and 60-s (43.8 ± 18.9; p-value <0.001) trials. In the time comparison task, the VCI/VD group had significantly fewer correct answers than that in the SCI groups (6.0 ± 1.3 vs. 7.1 ± 0.9, p-value <0.001). Correlation analysis revealed that multiple cognitive functions are involved in the time perception tasks. ConclusionsPatients with VCI/VD had the poorest time perception. These findings may provide a modest contribution to understanding the underlying pathophysiology and psychological connections related to temporal abilities in time perception.

Global relations versus object relations in visual analogies

Based on the distinction between global and local levels of visual perception, here we studied different levels of reasoning in visual analogies. Specifically, we created problems that could be solved by inferring relations either between the global shapes (global path) or the underlying objects (object path). The problems varied in the saliency of the global shape, in the colour and familiarity of the objects, and in the presentation of the visual problem (simultaneous or sequential). The results of three studies showed that the global path was used more frequently than the object path, particularly for images with salient global shapes such as objects placed in a circle. However, neither colour nor object familiarity affected the tendency to use the object path. Importantly, the tendency to use the global path correlated with analogical problem-solving in other visual and verbal tasks. Overall, these findings suggest that the global precedence observed in image perception also applies to visual analogical reasoning. Furthermore, the tendency to use the global path can be regarded as an informative measure of individual differences.

The silicon service spectrum: warmth and competence explain people's preferences for AI assistants

IntroductionThe past year has seen the rise of many variants of large language model chatbots that all attempt to carry out verbal tasks requested by users. These chatbots perform various collaborative tasks, such as brainstorming, question and answering, summarization, and holding other forms of conversations, embedding them within our daily society. As these AI assistants become increasingly integrated into societal structures, understanding people's perceptions toward them offers insights into how to better facilitate that integration, and how different our current understanding of human-human interactions parallels human-AI interactions. This project explores people's preferences toward responses generated by various chatbots.MethodsLeveraging a comprehensive dataset composed of thousands of pairwise comparisons of responses from 17 popular chatbots, we applied multidimensional scaling (MDS) and property fitting (PROFIT) methodologies to uncover the dimensionality of why some models are similarly or dissimilarly preferred on average by people.ResultsIn line with previous research on universal dimensions of social cognition, interactions with chatbots are predominantly perceived along two dimensions: warmth and competence. Also similar to social cognition applied to humans, the dimensions displayed a curvilinear trend where the highest levels of default warmth are found in models with moderate levels of competence. Models at extremely high and extremely low levels of competence tended to have lower levels of default warmth.DiscussionThis research advances our understanding of the interface between technology and social psychology. As chatbots and AI become increasingly prevalent within societal interactions, we see that many of the same principles found in perceptions between humans can also apply to AI.

A behavioral and eye movement study on inhibitory processing of action memory

Recent evidence highlights the critical role of effective interference inhibition for optimal memory performance, yet its function in action memory remains relatively underexplored. The current study investigated inhibitory processes in action memory during encoding and storage stages. In Experiment 1, 100 participants were divided into high and low cognitive inhibition groups using the Stroop color naming task. They performed either a subject-performed task (SPT) or a verbal task (VT) under varying semantic interference levels to assess the interaction between individual inhibitory abilities and the inhibition processing of action memory during encoding. Results indicated no significant difference in inhibition effects (IF) between high and low inhibition groups in SPT under high semantic interference, while in VT, those with high cognitive inhibition demonstrated significantly greater IF than those with low. Experiment 2, involving 57 participants, employed a point detection task and eye-tracking to explore attentional inhibition mechanisms during action memory storage. Behavioral results showed greater IF for SPT than VT under semantic interference. Eye-tracking revealed higher initial fixation rates and shorter durations for SPT subjects during the early processing stage, and significantly fewer and shorter fixations in the later stage compared to VT subjects. These findings imply stronger inhibitory processing in SPT during both encoding and storage stages under semantic interference, with attentional inhibition of action memories occurring predominantly in the later stage.

The role of answer content and length when preparing answers to questions

Research suggests that interlocutors manage the timing demands of conversation by preparing what they want to say early. In three experiments, we used a verbal question-answering task to investigate what aspects of their response speakers prepare early. In all three experiments, participants answered more quickly when the critical content (here, barks) necessary for answer preparation occurred early (e.g., Which animal barks and is also a common household pet?) rather than late (e.g., Which animal is a common household pet and also barks?). In the individual experiments, we found no convincing evidence that participants were slower to produce longer answers, consisting of multiple words, than shorter answers, consisting of a single word. There was also no interaction between these two factors. A combined analysis of the first two experiments confirmed this lack of interaction, and demonstrated that participants were faster to answer questions when the critical content was available early rather than late and when the answer was short rather than long. These findings provide tentative evidence for an account in which interlocutors prepare the content of their answer as soon as they can, but sometimes do not prepare its length (and thus form) until they are ready to speak.

Scalp Electroencephalogram-Derived Involvement Indexes during a Working Memory Task Performed by Patients with Epilepsy.

Electroencephalography (EEG) wearable devices are particularly suitable for monitoring a subject's engagement while performing daily cognitive tasks. EEG information provided by wearable devices varies with the location of the electrodes, the suitable location of which can be obtained using standard multi-channel EEG recorders. Cognitive engagement can be assessed during working memory (WM) tasks, testing the mental ability to process information over a short period of time. WM could be impaired in patients with epilepsy. This study aims to evaluate the cognitive engagement of nine patients with epilepsy, coming from a public dataset by Boran et al., during a verbal WM task and to identify the most suitable location of the electrodes for this purpose. Cognitive engagement was evaluated by computing 37 engagement indexes based on the ratio of two or more EEG rhythms assessed by their spectral power. Results show that involvement index trends follow changes in cognitive engagement elicited by the WM task, and, overall, most changes appear most pronounced in the frontal regions, as observed in healthy subjects. Therefore, involvement indexes can reflect cognitive status changes, and frontal regions seem to be the ones to focus on when designing a wearable mental involvement monitoring EEG system, both in physiological and epileptic conditions.

From long-term to short-term: Distinct neural networks underlying semantic knowledge and its recruitment in working memory

Although numerous studies suggest that working memory (WM) and semantic long-term knowledge interact, the nature and underlying neural mechanisms of this intervention remain poorly understood. Using functional magnetic resonance imaging (fMRI), this study investigated the extent to which neural markers of semantic knowledge in long-term memory (LTM) are activated during the WM maintenance stage in 32 young adults. First, the multivariate neural patterns associated with four semantic categories were determined via an implicit semantic activation task. Next, the participants maintained words – the names of the four semantic categories implicitly activated in the first task – in a verbal WM task. Multi-voxel pattern analyses showed reliable neural decoding of the four semantic categories in the implicit semantic activation and the verbal WM tasks. Critically, however, no between-task classification of semantic categories was observed. Searchlight analyses showed that for the WM task, semantic category information could be decoded in anterior temporal areas associated with abstract semantic category knowledge. In the implicit semantic activation task, semantic category information was decoded in superior temporal, occipital and frontal cortices associated with domain-specific semantic feature representations. These results indicate that item-level semantic activation during verbal WM involves shallow rather than deep semantic information.

Neuromodulation of the Right Motor Cortex of the Lips With Repetitive Transcranial Magnetic Stimulation to Reduce Phonological Impairment and Improve Naming in Three Persons With Aphasia: A Single-Case Experimental Design.

Repetitive transcranial magnetic stimulation (rTMS) can enhance aphasia recovery. Most studies have used inhibitory stimulation targeting the right inferior frontal gyrus. However, the motor cortex, observed to contribute to the prediction of aphasia recovery, is involved in word production and could be an appropriate target for rTMS. We aimed to observe behavioral changes in a picture naming task induced by inhibitory rTMS targeting the right motor cortex of the lips in people with poststroke aphasia. Using a single-case experimental design, we included three participants with chronic poststroke aphasia who had phonological deficits. Each participant performed a verbal picture naming task 3 times a week for 2, 3, or 4 weeks (pseudorandom across participants) to establish a baseline naming ability for each participant. These were not therapy sessions, and no feedback was provided. Then, each participant received the intervention, inhibitory continuous theta burst stimulation targeting the right motor cortex of the lips, 3 times a week for 2 weeks. Naming testing continued 3 times a week, for these latter 2 weeks. No therapy was performed at any time during the study. Visual analysis of the graphs showed a positive effect of rTMS for P2 and P3 on picture naming accuracy and a tendency toward improvement for P1. Statistical analysis showed an improvement after rTMS for P1 (τ = 0.544, p = .013, SETau = 0.288) and P2 (τ = 0.708, p = .001, SETau = 0.235). For P3, even if the intervention allowed some improvement, this was statistically nonsignificant due to a learning effect during the baseline naming testing, which lasted the longest, 4 weeks. Regarding specific language features, phonological errors significantly decreased in all patients. The motor cortex of the lips could be an appropriate target for rTMS to improve naming in people with poststroke aphasia suffering from a phonological deficit. This suggests the possibility to individualize the target for rTMS, according to the patient's linguistic impairment.

Effects of endogenous testosterone on oscillatory activity during verbal working memory in youth.

Testosterone levels sharply rise during the transition from childhood to adolescence and these changes are known to be associated with changes in human brain structure. During this same developmental window, there are also robust changes in the neural oscillatory dynamics serving verbal working memory processing. Surprisingly, whereas many studies have investigated the effects of chronological age on the neural oscillations supporting verbal working memory, none have probed the impact of endogenous testosterone levels during this developmental period. Using a sample of 89 youth aged 6-14 years-old, we collected salivary testosterone samples and recorded magnetoencephalography during a modified Sternberg verbal working memory task. Significant oscillatory responses were identified and imaged using a beamforming approach and the resulting maps were subjected to whole-brain ANCOVAs examining the effects of testosterone and sex, controlling for age, during verbal working memory encoding and maintenance. Our primary results indicated robust testosterone-related effects in theta (4-7 Hz) and alpha (8-14 Hz) oscillatory activity, controlling for age. During encoding, females exhibited weaker theta oscillations than males in right cerebellar cortices and stronger alpha oscillations in left temporal cortices. During maintenance, youth with greater testosterone exhibited weaker alpha oscillations in right parahippocampal and cerebellar cortices, as well as regions across the left-lateralized language network. These results extend the existing literature on the development of verbal working memory processing by showing region and sex-specific effects of testosterone, and are the first results to link endogenous testosterone levels to the neural oscillatory activity serving verbal working memory, above and beyond the effects of chronological age.

Neural underpinnings of memory encoding and retrieval: Validation of a novel ecologically valid fMRI paradigm

Cognitive impairment is prevalent in affective disorders. Currently, there is a lack of effective treatment options, which is partly due to limited insight into their neural underpinnings and poor transfer to everyday life. Integrating neuroimaging measures in cognition trials to identify neurocircuitry biomarkers is crucial for treatment development. We pooled baseline data from two clinical trials to validate a novel functional magnetic resonance imaging (fMRI) paradigm simulating real-life verbal learning and memory tasks. Healthy participants with no psychiatric history (n = 34) underwent fMRI and an ecologically valid virtual reality-based verbal memory task. During fMRI, they performed an ecologically valid paradigm involving encoding and recognition of a grocery shopping list. Whole-brain analyses assessed task-related activation in key neural networks. Neural underpinnings of memory encoding involved the hippocampus, prefrontal, temporal, occipital, and parietal regions, and caudate. Recognition task activation encompassed a network of frontal, parietal, temporal, and occipital regions. Positive associations were found between encoding-related activity in the inferior temporal gyrus and lateral occipital cortex and the number of correctly recalled grocery items. This study introduces and validates a novel fMRI paradigm for assessing real-life verbal learning and memory abilities. The identified neural underpinnings highlight the involvement of diverse brain regions in encoding and recognition processes that may be implemented in future investigations of the neural correlates of memory impairment and improvement.

Exploring Bilingual Benefits: Verbal and Nonverbal Information Updating in Working Memory

Objectives: The present study aimed to confirm the cognitive advantages of bilingualism specifically in the domain of working memory updating. Methods: A total of sixty adults (aged 20 to 26) participated in the study, divided into three groups based on bilingual status: Bilingual-similar (n = 20), Bilingual-Mongolian weighted (n = 20), and Monolingual (n = 20). Participants completed working memory update tasks involving verbal or nonverbal stimuli. Information updated in working memory could be derived from perceptual input or long-term memory. Results: Bilingual advantages in working memory updating was found in both verbal and nonverbal task. The advantages in working memory updating depending on stimuli (verbal or nonverbal) exhibited similar patterns. However, the patterns of bilingual advantages varied depending on the source of information (perceptual input or long-term memory). While both bilingual groups showed advantages when the information source was perceptual input, only the Bilingual-similar group showed advantages when the source was long-term memory. Conclusion: The study provides further empirical support for the cognitive benefits associated with bilingualism, particularly in the realm of working memory updating. The current findings underscore the notion that bilinguals optimize domain-general cognitive control. Further research is needed to investigate the underlying mechanisms of information management in bilingual individuals across different information resources.

Refraining from spontaneous face touch is linked to personality traits, reduced memory performance and EEG changes

Spontaneous touches of one’s face (sFST) were suggested to serve cognitive-emotional regulation processes. During the pandemic, refraining from face-touching was recommended, yet, accompanying effects and the influence of personal attributes remain unclear. Ninety participants (45 female, 45 male) filled out a questionnaire concerning personality, anxiety screening and ADHD screening. Subsequently, they performed a delayed verbal memory recall task four times. After two times, sixty participants were instructed to refrain from face-touching (experimental group). Thirty participants did not receive behavioral instructions (control group). To identify face-touches and conduct further analysis, Video, EMG, and EEG data were recorded. Two samples were formed, depending on the adherence to completely refrain from face-touching (adherent, non-adherent sample) and compared to each other and the control group. EEG analyses uncovered that refraining from face-touching is accompanied by increased beta-power at sensorimotor sites and, exclusively in the non-adherent sample, at frontal sites. Decreased memory performance was found exclusively in subsamples, who non-adherently touched their face while retaining words. In terms of questionnaire results, lower Conscientiousness and higher ADHD screening scores were revealed by the non-adherent compared to the adherent sample. No differences were found among the subsamples. The presented results indicate that refraining from face-touching is related to personal attributes, accompanied by neurophysiological shifts and for a portion of humans by lower memory performance, supporting the notion that sFST serve processes beyond sensorimotor.

Reading direction interacts with spatial processes of temporal order verbal working memory: evidence from Iranian right-to-left readers

ABSTRACT Reading direction affects cognitive processes such as spatial processing and attention. Testing Farsi right-to-left readers, we investigated the effect of reading direction on the involved spatial and attentional processes in a verbal working memory task. Previous research in left-to-right readers has shown that serial order in verbal WM is encoded spatially from left to right and that mechanisms of spatial attention operate on these mental representations. First, we confirmed that the spatial representation of serial information in WM follows the right-to-left reading direction of Farsi. Second, we demonstrated the influence of reading direction on the distribution of spatial attention over the reading-direction-contingent mental representation of serial information in WM. Behavioural RTs and neural markers of spatial attention shifts (EDAN and ADAN ERPs and lateralised posterior alpha activity) confirm the right-to-left representation of serial order in WM and the involvement of spatial attention in retrieving items from this mnemonic space.

Application of the Japanese Verbal Learning Test to Patients With Alzheimer's Disease in the Early Stage.

This study aimed to investigate the mechanism of memory function in the context of explicit memory in early-stage Alzheimer's disease (AD) using the short-form Japanese Verbal Learning Test (JVLT-9). Participants were 20 patients with early-stage AD and a control group of 23 healthy older adults (normal controls: NC), each of whom was administered the JVLT-9, which is a verbal list learning task used to assess explicit memory comprehensively. Between-group differences for each score were investigated using the Mann-Whitney U test. A two-way analysis of variance (ANOVA) was performed for the number of correct recalls by group (AD/NC) × JVLT-9 task. In addition, the AD group was divided into a CDR 0.5 group and a CDR 1.0 group, and it was performed as a group (CDR 0.5/1.0) × JVLT-9 task two-way ANOVA. The results demonstrated that the AD group had lower immediate recall, learning rate, semantic clustering, and recognition discrimination and significantly higher intrusion errors compared to the NC group. Further, JVLT-9 recall and recognition rates were found to be lower with higher CDR (an index of dementia severity). These results are largely consistent with the features of explicit memory in AD reported in the English version, confirming the clinical utility of the JVLT-9 as a test of explicit memory function.