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Paul Maruff - One of the best experts on this subject based on the ideXlab platform.
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visual Paired Associate learning deficits Associated with elevated beta amyloid in cognitively normal older adults
Neuropsychology (journal), 2019Co-Authors: Jenalle E Baker, Robert H Pietrzak, Paul Maruff, Simon M Laws, David Ames, Victor L Villemagne, Christopher C Rowe, Colin L Masters, Yen Ying LimAbstract:Objective Previous studies have shown that Paired Associate learning (PAL), a type of episodic memory, is imPaired in early Alzheimer's disease (AD). Such tasks require that a set of associations (e.g., pattern-location) be learned over several trials, and the objective is to reduce errors with each trial. Currently, the nature and magnitude of impairment and decline on PAL measures in cognitively normal (CN) older adults with elevated levels of beta-amyloid (Aβ+) is unknown. Method This study examined PAL errors in Aβ+ and Aβ - CN older adults, both within a single assessment and over time. Participants (210 Aβ - CN, 146 Aβ + CN) from the Australian Imaging, Biomarkers, and Lifestyle (AIBL) study underwent three assessments over 36-months (baseline, and 18- and 36-month follow-ups) using a computerized Paired Associate learning task (CPAL). Aβ status was determined by positron emission tomography (PET) neuroimaging. Results No significant group differences in PAL were evident at baseline. Significant groupxtime interactions were observed, with the Aβ - CN group, but not the Aβ + CN group, evidencing improvement over time (Cohen's d = 0.30 [0.08, 0.51]). Despite this, no group differences were evident at 36-months. Conclusions Results suggest that PAL dysfunction is evident over time in Aβ + CNs. This indicates a lack of benefit from repeated exposure to the task over time Associated with Aβ+, which is not the case for Aβ - CNs. Further, results suggest that assessing change in Aβ+ related cognition over time, rather than at a single assessment, provides greater understanding of dysfunction in early AD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
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a process based approach to characterizing the effect of acute alprazolam challenge on visual Paired Associate learning and memory in healthy older adults
Human Psychopharmacology-clinical and Experimental, 2012Co-Authors: Robert H Pietrzak, Peter J Snyder, James Cobb Scott, Brian T Harel, Yen Ying Lim, Paul MaruffAbstract:Objective Alprazolam is a benzodiazepine that, when administered acutely, results in impairments in several aspects of cognition, including attention, learning, and memory. However, the profile (i.e., component processes) that underlie alprazolam-related decrements in visual Paired Associate learning has not been fully explored. Methods In this double-blind, placebo-controlled, randomized cross-over study of healthy older adults, we used a novel, “process-based” computerized measure of visual Paired Associate learning to examine the effect of a single, acute 1-mg dose of alprazolam on component processes of visual Paired Associate learning and memory. Results Acute alprazolam challenge was Associated with a large magnitude reduction in visual Paired Associate learning and memory performance (d = 1.05). Process-based analyses revealed significant increases in distractor, exploratory, between-search, and within-search error types. Analyses of percentages of each error type suggested that, relative to placebo, alprazolam challenge resulted in a decrease in the percentage of exploratory errors and an increase in the percentage of distractor errors, both of which reflect memory processes. Conclusions Results of this study suggest that acute alprazolam challenge decreases visual Paired Associate learning and memory performance by reducing the strength of the association between pattern and location, which may reflect a general breakdown in memory consolidation, with less evidence of reductions in executive processes (e.g., working memory) that facilitate visual Paired Associate learning and memory. Copyright © 2012 John Wiley & Sons, Ltd.
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understanding failure of visual Paired Associate learning in amnestic mild cognitive impairment
Journal of Clinical and Experimental Neuropsychology, 2011Co-Authors: Jade Odonnell, Robert H Pietrzak, Kathryn Ellis, Peter J Snyder, Paul MaruffAbstract:Impairment in visual Paired Associate learning occurs often in with amnestic mild cognitive impairment (aMCI), a condition considered to be an early stage of Alzheimer's disease (AD). To date, studies of aMCI have characterized imPaired visual Paired Associate learning only in terms of summary scores such as total errors or total trials to criterion. The aim of this study was to determine the nature and magnitude of errors made on a continuous Paired Associate learning (CPAL) task designed to allow analysis of the component processes involved in Paired Associate learning. Twenty-one individuals with aMCI and 54 healthy age-matched older adults (HC) performed the CPAL task in which they had to learn six pattern-location pairings over six trials. Results suggested that aMCI patients performed significantly worse on the CPAL, both in learning rate and in error accumulation. Qualitative analyses of CPAL performance revealed that in aMCI there were significantly more errors on all indices except perseverative errors. When expressed as a percentage of total errors, abnormalities occurred only for within-search and exploratory errors. These findings suggest that poor performance on visual Paired Associate learning tasks in aMCI reflects impairments in both learning and executive function.
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examining the nature of impairment in visual Paired Associate learning in amnestic mild cognitive impairment
Neuropsychology (journal), 2011Co-Authors: Brian T Harel, Robert H Pietrzak, Peter J Snyder, David Darby, Kathryn A Ellis, Paul MaruffAbstract:OBJECTIVE: Visual spatial learning is imPaired in mild cognitive impairment (MCI) although the nature of this impairment is not clear. This study investigated the nature and magnitude of errors made by adults with amnestic MCI (aMCI) when learning pattern-location Paired associations in a continuous manner. METHOD: Visual Associate learning was measured using the Continuous Paired Associate Learning (CPAL) task in which 30 adults who met clinical criteria for aMCI and 30 matched controls were required to learn a set of associations between patterns and locations across increasing memory loads (two, four, six, and eight). RESULTS: As hypothesized, the aMCI group made more total errors than controls for all memory loads above two. However, the rate of increase in errors with memory load in the aMCI group was approximately twice that for controls. CONCLUSIONS: In controls, errors on the CPAL task reflected almost exclusively difficulty in memory. In the aMCI group, errors on the CPAL reflected limitations in associative learning but also in short-term memory and response monitoring. These results suggest that impairments in specific aspects of executive function and working memory might contribute to poor performance on visual Paired Associate learning in aMCI.
Liping Wang - One of the best experts on this subject based on the ideXlab platform.
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neural correlates of feedback processing in visuo tactile crossmodal Paired Associate learning
Frontiers in Human Neuroscience, 2018Co-Authors: Peng Gui, Xianzhen Zhou, Mark Bodner, F A Lenz, Xiaowei Dong, Liping Wang, Yongdi ZhouAbstract:Previous studies have examined the neural correlates for crossmodal Paired-Associate (PA) memory and the temporal dynamics of its formation. However, the neural dynamics for feedback processing of crossmodal PA learning remain unclear. To examine this process, we recorded event-related scalp electrical potentials for PA learning of unimodal visual-visual pairs and crossmodal visual-tactile pairs when participants performed unimodal and crossmodal tasks. We examined event-related potentials (ERPs) after the onset of feedback in the tasks for three effects: feedback type (positive feedback vs. negative feedback), learning (as the learning progressed) and the task modality (crossmodal vs. unimodal). The results were as follows: (1) feedback type: the amplitude of P300 decreased with incorrect trials and the P400/N400 complex was only present in incorrect trials; (2) learning: progressive positive voltage shifts in frontal recording sites and negative voltage shifts in central and posterior recording sites were identified as learning proceeded; and (3) task modality: compared with the unimodal PA learning task, positive voltage shifts in frontal sites and negative voltage shifts in posterior sites were found in the crossmodal PA learning task. To sum up, these results shed light on cortical excitability related to feedback processing of crossmodal PA learning.
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neural correlates of visuo tactile crossmodal Paired Associate learning and memory in humans
Neuroscience, 2017Co-Authors: Peng Gui, Mark Bodner, F A Lenz, Liping Wang, Yong Di ZhouAbstract:Studies have indicated that a cortical sensory system is capable of processing information from different sensory modalities. However, it still remains unclear when and how a cortical system integrates and retains information across sensory modalities during learning. Here we investigated the neural dynamics underlying crossmodal associations and memory by recording event-related potentials (ERPs) when human participants performed visuo-tactile (crossmodal) and visuo-visual (unimodal) Paired-Associate (PA) learning tasks. In a trial of the tasks, the participants were required to explore and learn the relationship (Paired or non-Paired) between two successive stimuli. EEG recordings revealed dynamic ERP changes during participants' learning of Paired-associations. Specifically, (1) the frontal N400 component showed learning-related changes in both unimodal and crossmodal tasks but did not show any significant difference between these two tasks, while the central P400 displayed both learning changes and task differences; (2) a late posterior negative slow wave (LPN) showed the learning effect only in the crossmodal task; (3) alpha-band oscillations appeared to be involved in crossmodal working memory. Additional behavioral experiments suggested that these ERP components were not relevant to the participants' familiarity with stimuli per se. Further, by shortening the delay length (from 1300ms to 400ms or 200 ms) between the first and second stimulus in the crossmodal task, declines in participants' task performance were observed accordingly. Taken together, these results provide insights into the cortical plasticity (induced by PA learning) of neural networks involved in crossmodal associations in working memory.
Kate Nation - One of the best experts on this subject based on the ideXlab platform.
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The nature and specificity of Paired Associate learning deficits in children with dyslexia
Journal of Memory and Language, 2014Co-Authors: Robin A. Litt, Kate NationAbstract:Abstract We report three experiments investigating the specificity and nature of Paired Associate learning (PAL) deficits in children with dyslexia. Experiments 1 and 2 compared children with dyslexia and age-matched controls across the following stimulus–response mapping conditions, designed to dissociate crossmodal and verbal demands: visual–verbal, verbal–verbal, visual–visual, and verbal–visual. Children with dyslexia exhibited deficits in visual–verbal and verbal–verbal PAL only. Experiment 3 investigated the stage of learning in which PAL deficits arise by separating the verbal learning and associative learning components of a visual–verbal PAL task. Results revealed an item-specific relationship between phonological form learning and later associative learning success. Visual–verbal PAL deficits were fully accounted for by the preceding deficit in phonological form learning. Together, our results show that PAL deficits in dyslexia are not a consequence of difficulties with associative learning; instead, they are best characterized as deficits in phonological form learning. The implications of these findings for theories of reading development and dyslexia are discussed.
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dissociating crossmodal and verbal demands in Paired Associate learning pal what drives the pal reading relationship
Journal of Experimental Child Psychology, 2013Co-Authors: Robin A. Litt, Peter F De Jong, Elsje Van Bergen, Kate NationAbstract:Recent research suggests that visual-verbal Paired Associate learning (PAL) may tap a crossmodal associative learning mechanism that plays a distinct role in reading development. However, evidence from children with dyslexia indicates that deficits in visual-verbal PAL are strongly linked to the verbal demands of the task. The primary aim of this study was to disAssociate the role of modality and verbal demand in driving the PAL-reading relationship. To do so, we compared performance across four PAL mapping conditions: visual-verbal, verbal-verbal, visual-visual and verbal-visual. We reasoned that if crossmodal mapping demand accounts for the PAL-reading relationship, both visual-verbal PAL and verbal-visual PAL should exhibit significant relationships with reading ability. The results were incompatible with the crossmodal hypothesis. Only tasks requiring verbal output (visual-verbal PAL and verbal-verbal PAL) significantly correlated with reading ability. In addition, visual-verbal PAL and verbal-verbal PAL were well represented by a latent "verbal output PAL" factor. Structural equation modeling showed that this factor fully accounted for the PAL-reading relationship; visual-verbal PAL did not add anything to the prediction of reading above and beyond this latent factor. The results are interpreted according to an alternative verbal account of the PAL-reading relationship.
Robin A. Litt - One of the best experts on this subject based on the ideXlab platform.
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Paired Associate learning deficits in poor readers the contribution of phonological input and output processes
Quarterly Journal of Experimental Psychology, 2019Co-Authors: Robin A. Litt, Hua Chen Wang, Jessica Sailah, Nicholas A Badcock, Anne CastlesAbstract:It is well-established that poor readers exhibit deficits in Paired Associate learning (PAL), and there is increasing evidence for a phonological locus of these deficits. However, it remains unclea...
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The nature and specificity of Paired Associate learning deficits in children with dyslexia
Journal of Memory and Language, 2014Co-Authors: Robin A. Litt, Kate NationAbstract:Abstract We report three experiments investigating the specificity and nature of Paired Associate learning (PAL) deficits in children with dyslexia. Experiments 1 and 2 compared children with dyslexia and age-matched controls across the following stimulus–response mapping conditions, designed to dissociate crossmodal and verbal demands: visual–verbal, verbal–verbal, visual–visual, and verbal–visual. Children with dyslexia exhibited deficits in visual–verbal and verbal–verbal PAL only. Experiment 3 investigated the stage of learning in which PAL deficits arise by separating the verbal learning and associative learning components of a visual–verbal PAL task. Results revealed an item-specific relationship between phonological form learning and later associative learning success. Visual–verbal PAL deficits were fully accounted for by the preceding deficit in phonological form learning. Together, our results show that PAL deficits in dyslexia are not a consequence of difficulties with associative learning; instead, they are best characterized as deficits in phonological form learning. The implications of these findings for theories of reading development and dyslexia are discussed.
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dissociating crossmodal and verbal demands in Paired Associate learning pal what drives the pal reading relationship
Journal of Experimental Child Psychology, 2013Co-Authors: Robin A. Litt, Peter F De Jong, Elsje Van Bergen, Kate NationAbstract:Recent research suggests that visual-verbal Paired Associate learning (PAL) may tap a crossmodal associative learning mechanism that plays a distinct role in reading development. However, evidence from children with dyslexia indicates that deficits in visual-verbal PAL are strongly linked to the verbal demands of the task. The primary aim of this study was to disAssociate the role of modality and verbal demand in driving the PAL-reading relationship. To do so, we compared performance across four PAL mapping conditions: visual-verbal, verbal-verbal, visual-visual and verbal-visual. We reasoned that if crossmodal mapping demand accounts for the PAL-reading relationship, both visual-verbal PAL and verbal-visual PAL should exhibit significant relationships with reading ability. The results were incompatible with the crossmodal hypothesis. Only tasks requiring verbal output (visual-verbal PAL and verbal-verbal PAL) significantly correlated with reading ability. In addition, visual-verbal PAL and verbal-verbal PAL were well represented by a latent "verbal output PAL" factor. Structural equation modeling showed that this factor fully accounted for the PAL-reading relationship; visual-verbal PAL did not add anything to the prediction of reading above and beyond this latent factor. The results are interpreted according to an alternative verbal account of the PAL-reading relationship.
Charles Hulme - One of the best experts on this subject based on the ideXlab platform.
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verbal task demands are key in explaining the relationship between Paired Associate learning and reading ability
Journal of Experimental Child Psychology, 2018Co-Authors: Francina Jane Clayton, Claire Sears, Alice Davis, Charles HulmeAbstract:Paired-Associate learning (PAL) tasks measure the ability to form a novel association between a stimulus and a response. Performance on such tasks is strongly Associated with reading ability, and there is increasing evidence that verbal task demands may be critical in explaining this relationship. The current study investigated the relationships between different forms of PAL and reading ability. A total of 97 children aged 8-10 years completed a battery of reading assessments and six different PAL tasks (phoneme-phoneme, visual-phoneme, nonverbal-nonverbal, visual-nonverbal, nonword-nonword, and visual-nonword) involving both familiar phonemes and unfamiliar nonwords. A latent variable path model showed that PAL ability is captured by two correlated latent variables: auditory-articulatory and visual-articulatory. The auditory-articulatory latent variable was the stronger predictor of reading ability, providing support for a verbal account of the PAL-reading relationship.
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phoneme awareness visual verbal Paired Associate learning and rapid automatized naming as predictors of individual differences in reading ability
Scientific Studies of Reading, 2012Co-Authors: Meesha Warmingto, Charles HulmeAbstract:This study examines the concurrent relationships between phoneme awareness, visual-verbal Paired-Associate learning, rapid automatized naming (RAN), and reading skills in 7- to 11-year-old children. Path analyses showed that visual-verbal Paired-Associate learning and RAN, but not phoneme awareness, were unique predictors of word recognition, whereas visual-verbal Paired-Associate learning, RAN, and phoneme awareness were predictors of nonword reading. These results suggest that visual-verbal Paired-Associate learning, RAN, and phoneme awareness tap related but far-from-identical processes and are important predictors of different aspects of reading skills in children.
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Paired Associate learning phoneme awareness and learning to read
Journal of Experimental Child Psychology, 2007Co-Authors: Charles Hulme, Kristina Goetz, Debbie Gooch, Joh W Adams, Margare J SnowlingAbstract:We report two studies examining the relations among three Paired-Associate learning (PAL) tasks (visual–visual, verbal–verbal, and visual–verbal), phoneme deletion, and single-word and nonword reading ability. Correlations between the PAL tasks and reading were strongest for the visual–verbal task. Path analyses showed that both phoneme deletion and visual–verbal PAL were unique predictors of a composite measure of single-word reading and of irregular word reading. However, for nonword reading, phoneme deletion was the only unique predictor (and visual–verbal PAL was not a significant predictor). These results are consistent with the view that learning visual (orthography) to phonological mappings is an important skill for developing word recognition skills in reading and that individual differences in this ability can be tapped experimentally by a PAL task.
