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The present study aimed to delineate the extent to which unitary executive functions might be shared across the separate domains of episodic and working memory. A mixed blocked/event-related functional magnetic resonance imaging (fMRI) design was employed to assess sustained (tonic control) and transient (phasic control) brain responses arising from incrementing executive demand (source versus item episodic memory – vis-à-vis – two-back versus one-back working memory) using load-dependent activation overlaps as indices of common components. Although an extensive portion of the regional load effects constituted differential control modulations in both sustained and transient responses, commonalities were also found implicating a subset of executive core mechanisms consistent with unitary or domain general control. ‘Unitary’ control modulations were temporally dissociated into (1) shared tonic components involving medial and lateral prefrontal cortex, striatum, cerebellum and superior parietal cortex, assumed to govern enhanced top-down context processing, monitoring and sustained attention throughout task periods and (2) stimulus-synchronous phasic components encompassing posterior intraparietal sulcus, hypothesized to support dynamic shifting of the ‘focus of attention’ among internal representations. Taken together, these results converge with theoretical models advocating both unity and diversity among executive control processes.

Higher rates of alcohol use have been reported in HIV+ individuals compared to the general population. Both heavy alcohol use and HIV infection are associated with increased risk of neuropsychological (NP) impairment. We examined effects of heavy active alcohol use and HIV on NP functioning in a large sample of community-residing HIV+ individuals and HIV− controls. The four main study groups included 72 HIV− light/non-drinkers, 70 HIV− heavy drinkers (>100 drinks per month), 70 HIV+ light/non-drinkers, and 56 HIV+ heavy drinkers. The heavy drinking group was further subdivided to assess effects of the heaviest levels of active alcohol use (>6 drinks per day) on NP functioning. A comprehensive NP battery was administered. Multivariate analysis of covariance was employed to examine the effect of HIV and alcohol on NP functioning after adjusting for group differences in age and estimated premorbid verbal intellectual functioning. The analyses identified main effects of heavy drinking and HIV on NP function, with greatest effects involving the contrast of HIV+ heavy drinkers and the HIV− light drinkers. Synergistic effects of heaviest current drinking and HIV infection were identified in analyses of motor and visuomotor speed. Supplementary analyses also revealed better NP function in the HIV+ group with antiretroviral treatment (ART) and lower level of viral burden, a finding that was consistent across levels of alcohol consumption. Finally, heavy alcohol use and executive functioning difficulties were associated with lower levels of self-reported medication adherence in the HIV+ group. The findings suggest that active heavy alcohol use and HIV infection have additive adverse effects on NP function, that they may show synergistic effects in circumstances of very heavy active alcohol use, and that heavy drinking and executive functioning may mediate health-related behaviors in HIV disease. (JINS, 2005, 11, 70–83.)

Making sense of the world around us depends upon selectively retrieving information relevant to our current goal or context. However, it is unclear whether selective semantic retrieval relies exclusively on general control mechanisms recruited in demanding non-semantic tasks, or instead on systems specialised for the control of meaning. One hypothesis is that the left posterior middle temporal gyrus (pMTG) is important in the controlled retrieval of semantic (not non-semantic) information; however this view remains controversial since a parallel literature links this site to event and relational semantics. In a functional neuroimaging study, we demonstrated that an area of pMTG implicated in semantic control by a recent meta-analysis was activated in a conjunction of (i) semantic association over size judgements and (ii) action over colour feature matching. Under these circumstances the same region showed functional coupling with the inferior frontal gyrus — another crucial site for semantic control. Structural and functional connectivity analyses demonstrated that this site is at the nexus of networks recruited in automatic semantic processing (the default mode network) and executively demanding tasks (the multiple-demand network). Moreover, in both task and task-free contexts, pMTG exhibited functional properties that were more similar to ventral parts of inferior frontal cortex, implicated in controlled semantic retrieval, than more dorsal inferior frontal sulcus, implicated in domain-general control. Finally, the pMTG region was functionally correlated at rest with other regions implicated in control-demanding semantic tasks, including inferior frontal gyrus and intraparietal sulcus. We suggest that pMTG may play a crucial role within a large-scale network that allows the integration of automatic retrieval in the default mode network with executively-demanding goal-oriented cognition, and that this could support our ability to understand actions and non-dominant semantic associations, allowing semantic retrieval to be ‘shaped’ to suit a task or context. [Display omitted] •Posterior middle temporal gyrus supports semantic control and event semantics.•pMTG is at nexus of the default mode and multiple-demand networks.•It links anterior temporal and prefrontal regions for representation and control.•pMTG connects with inferior frontal gyrus during tasks and at rest.•These sites form a semantic control network distinct from executive control.

In recent years, a significant effort has been made toward digitizing neuropsychological measures in an effort to increase accessibility. Results of this research demonstrate that digitized versions, when conducted in a supervised setting, are comparable to traditional paper-and-pencil tests. The validity of unsupervised online tests is less well known. In the present study we examined how an unsupervised, self-administered online version of a list learning task compares to traditional versions among a cognitively healthy, older adult sample. A community-based sample (n = 279) of English-speaking older adults, aged 60-96 (M = 73.8), with a mean education of 14.9 (range=10-20), majority female (52%), without existing neurocognitive diagnoses, self-administered a Qualtrics online survey from home, which included a digitized list learning task based on the Rey Auditory Verbal Learning Task (RAVLT). Participants were visually exposed to, and asked to recall, a novel list of 15 words over the course of three learning trials. Then they were presented with an interference list, and later asked to recall the initial list of words following a delay. Total correct words recalled from each trial were summed, and mean score differences were compared across gender, years of education, and age quartiles (Q2=68, Q3=74, Q4=80). Participants recalled an average of 5.4 (SD=2.7), 8.8 (SD=3.1), 10.0 (SD=3.2), and 7.0 (SD=3.9) words on Trials 1-3 and Delayed Recall respectively. Females recalled more words across all trials (all t tests p < .05). Neither education or age were significantly correlated with performance; however, upon further inspection, those in the second quartile (ages 68-73) recalled approximately one word more than the other age groups. Our results generally align well with published AVLT norms. They are also consistent with existing research suggesting that females perform better on verbal learning tasks. However, the absence of a relationship between performance and age or education suggests that the utilization of an unsupervised, digital verbal learning task must be approached with caution.

With the growth of the elderly population and the increasing incidence of diseases related to cognitive decline, there is a growing demand for effective cognitive screening methods. This study explores the application of a memory and learning test integrated with electroencephalographic (EEG) monitoring in healthy elderly individuals. The research aimed to investigate the correlation between cognitive performance and EEG changes during the test, providing a more comprehensive neurophysiological view of cognitive functions. The study was carried out using the Rey Auditory Verbal Learning Test (RAVLT), designed to assess episodic declarative memory through auditory verbal learning. EEG was used to measure brain wave activity during the test, with Delta, Theta, Alpha, Beta and Gamma waves being recorded for later analysis. The experimental phase involved 18 healthy elderly participants. Analysis of the EEG data revealed significant correlations between brainwave activity and cognitive performance. Specifically, higher levels of alpha activity were negatively correlated with immediate recall (rho = -0.529, p =  0.024) and delayed recall (rho = -0.593, p =  0.009), while higher levels of gamma activity were positively correlated with better performance in immediate recall (rho = 0.572, p =  0.013) and delayed recall (rho = 0.476, p =  0.046). Beta wave activity was negatively correlated with learning across trials during testing (rho = -0.536, p =  0.022). Cognitive testing combined with EEG monitoring shows promising potential for assessing cognitive function in the elderly. EEG integration allows deeper insights into the neurophysiological processes underlying cognitive performance. However, more studies are needed to validate its clinical applicability.

The present study performed a quantitative meta-analysis of functional MRI studies that used a subsequent memory approach. The meta-analysis considered both subsequent memory (SM; remembered>forgotten) and subsequent forgetting (SF; forgotten>remembered) effects, restricting the data used to that concerning visual information encoding in healthy young adults. The meta-analysis of SM effects indicated that they most consistently associated with five neural regions: left inferior frontal cortex (IFC), bilateral fusiform cortex, bilateral hippocampal formation, bilateral premotor cortex (PMC), and bilateral posterior parietal cortex (PPC). Direct comparisons of the SM effects between the studies using verbal versus pictorial material and item-memory versus associative-memory tasks yielded three main sets of findings. First, the left IFC exhibited greater SM effects during verbal material than pictorial material encoding, whereas the fusiform cortex exhibited greater SM effects during pictorial material rather than verbal material encoding. Second, bilateral hippocampal regions showed greater SM effects during pictorial material encoding compared to verbal material encoding. Furthermore, the left hippocampal region showed greater SM effects during pictorial-associative versus pictorial-item encoding. Third, bilateral PMC and PPC regions, which may support attention during encoding, exhibited greater SM effects during item encoding than during associative encoding. The meta-analysis of SF effects indicated they associated mostly with default-mode network regions, including the anterior and posterior midline cortex, the bilateral temporoparietal junction, and the bilateral superior frontal cortex. Recurrent activity oscillations between the task-positive and task-negative/default-mode networks may account for trial-to-trial variability in participants' encoding performances, which is a fundamental source of both SM and SF effects. Taken together, these findings clarify the neural activity that supports successful encoding, as well as the neural activity that leads to encoding failure. ► SM effects associated mostly with content processing, storage, and attention regions. ► SF effects associated mostly with default-mode network regions. ► The left IFC and fusiform cortex support content processing. ► The MTL supports storage operations ► The PMC and PPC support attention during encoding.

Signed languages exhibit iconicity (resemblance between form and meaning) across their vocabulary, and many non-Indo-European spoken languages feature sizable classes of iconic words known as ideophones. In comparison, Indo-European languages like English and Spanish are believed to be arbitrary outside of a small number of onomatopoeic words. In three experiments with English and two with Spanish, we asked native speakers to rate the iconicity of ~600 words from the English and Spanish MacArthur-Bates Communicative Developmental Inventories. We found that iconicity in the words of both languages varied in a theoretically meaningful way with lexical category. In both languages, adjectives were rated as more iconic than nouns and function words, and corresponding to typological differences between English and Spanish in verb semantics, English verbs were rated as relatively iconic compared to Spanish verbs. We also found that both languages exhibited a negative relationship between iconicity ratings and age of acquisition. Words learned earlier tended to be more iconic, suggesting that iconicity in early vocabulary may aid word learning. Altogether these findings show that iconicity is a graded quality that pervades vocabularies of even the most \"arbitrary\" spoken languages. The findings provide compelling evidence that iconicity is an important property of all languages, signed and spoken, including Indo-European languages.

In this paper we present a novel theory of the cognitive and neural processes by which adults learn new spoken words. This proposal builds on neurocomputational accounts of lexical processing and spoken word recognition and complementary learning systems (CLS) models of memory. We review evidence from behavioural studies of word learning that, consistent with the CLS account, show two stages of lexical acquisition: rapid initial familiarization followed by slow lexical consolidation. These stages map broadly onto two systems involved in different aspects of word learning: (i) rapid, initial acquisition supported by medial temporal and hippocampal learning, (ii) slower neocortical learning achieved by offline consolidation of previously acquired information. We review behavioural and neuroscientific evidence consistent with this account, including a meta-analysis of PET and functional Magnetic Resonance Imaging (fMRI) studies that contrast responses to spoken words and pseudowords. From this meta-analysis we derive predictions for the location and direction of cortical response changes following familiarization with pseudowords. This allows us to assess evidence for learning-induced changes that convert pseudoword responses into real word responses. Results provide unique support for the CLS account since hippocampal responses change during initial learning, whereas cortical responses to pseudowords only become word-like if overnight consolidation follows initial learning.

The relation of body side of motor symptom onset in Parkinson's disease (PD) to memory measures associated with hemispheric dominance was examined. Fourteen patients with right body side motor symptom onset (RPD, inferred left hemisphere dysfunction) and 16 patients with left side onset (LPD, right hemisphere dysfunction) were administered measures of verbal (Hopkins Verbal Learning Test-Revised) and visual memory (Brief Visual Memory Test-Revised), that require similar task demands and are associated with left or right hemisphere dominance, respectively. The LPD group demonstrated poorer visual than verbal memory, both within group and in comparison to the RPD group. By contrast, the RPD group showed poorer verbal than visual memory within group. These findings suggest that side of motor symptom onset is associated with asymmetrical memory dysfunction (JINS, 2006, 12, 736–740.)

The Digit span and Corsi span tasks are frequently used to assess verbal and visuo-spatial short-term memory. Forward versions of these tasks, in which sequences of items of increasing length have to be reproduced in the order they were presented, are believed to primarily evaluate the functioning of the working memory material-specific slave systems (i.e. the phonological loop and the visuo-spatial sketchpad for verbal and visuo-spatial data, respectively). The backward versions of both tasks, in which sequences of items have to be reproduced in the reverse order, are believed to primarily tax Central Executive resources. Here, we report normative data on the forward and backward versions of the Digit span and Corsi span tasks that was collected from 362 healthy Italians ranging in age from 20 to 90 years. The results show a decremental effect of age on performance in all tasks and an ameliorative effect of education in all tasks except the Corsi span backwards. We provide correction grids for age and literacy that derive from results of the regression analyses.