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Archives of Clinical Neuropsychology :... Jan 2022To investigate the differential ability of the "Test Relaties Abstracte Concepten" (TRACE), a Dutch test for abstract semantic knowledge, in frontotemporal dementia...
OBJECTIVE
To investigate the differential ability of the "Test Relaties Abstracte Concepten" (TRACE), a Dutch test for abstract semantic knowledge, in frontotemporal dementia (FTD).
METHODS
The TRACE was administered in patients with behavioral variant FTD (bvFTD; n = 16), nonfluent variant (nfvPPA; n = 10), logopenic variant (lvPPA; n = 10), and semantic variant primary progressive aphasia (svPPA; n = 9), and controls (n = 59). We examined group differences, performed correlational analyses with other neuropsychological tests and investigated discriminative ability. We compared the TRACE with a semantic association test for concrete stimuli (SAT).
RESULTS
All patient groups, except nfvPPA, performed worse on the TRACE than controls (p < .01). svPPA patients performed worse than the other patient groups (p < .05). The TRACE discriminated well between patient groups, except nfvPPA, versus controls (all p < .01) and between svPPA versus other patient groups with high sensitivity (75-100%) and specificity (86%-92%). In bvFTD and nfvPPA the TRACE correlated with language tests (ρ > 0.6), whereas in svPPA the concrete task correlated (ρ ≥ 0.75) with language tests. Patients with bvFTD, nfvPPA and lvPPA performed lower on the TRACE than the SAT (p < .05), whereas patients with svPPA were equally impaired on both tasks (p = .2).
DISCUSSION
We demonstrated impaired abstract semantic knowledge in patients with bvFTD, lvPPA, and svPPA, but not nfvPPA, with svPPA patients performing worse than the other subtypes. The TRACE was a good classifier between each patient group versus controls and between svPPA versus other patient groups. This highlights the value of incorporating semantic tests with abstract stimuli into standard neuropsychological assessment for early differential diagnosis of FTD subtypes.
Topics: Aphasia, Primary Progressive; Frontotemporal Dementia; Humans; Language; Neuropsychological Tests; Semantics
PubMed: 33856423
DOI: 10.1093/arclin/acab022 -
European Journal of Ageing Aug 2023The cognitive complaints encountered in late-life depression (LLD) make it difficult to distinguish from amnestic mild cognitive impairment (aMCI) and Alzheimer's... (Review)
Review
The role of semantic assessment in the differential diagnosis between late-life depression and Alzheimer's disease or amnestic mild cognitive impairment: systematic review and meta-analysis.
OBJECT
The cognitive complaints encountered in late-life depression (LLD) make it difficult to distinguish from amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) based on an analysis of neurocognitive disorders. The hypothesis of the early impairment of semantic memory in AD and aMCI is considered a potential differential cognitive clue, but the absence of this impairment has not yet been confirmed in LLD.
METHOD
Based on the PRISMA method, we systematically seek neuropsychological assessments of individuals with LLD, the present study included 31 studies representing 3291 controls and 2820 people with LLD. Wherever possible, studies that tested simultaneously groups with LLD, AD (or aMCI) were also included. The results of the group of neuropsychological tasks relying on semantic memory were analyzed in two groups of tasks with high- or low-executive demand. The mean average effect of LLD was calculated and compared to the incremental effect of aMCI or AD on the scores. Linear regressions including education, age, and severity and type of depression were run to seek their power of prediction for the mean average effects.
RESULTS
LLD has a medium effect on scores at semantic and phonemic fluency and naming and a small average effect on the low-executive demand tasks. Differences in education is a predictor of the effect of LLD on phonemic fluency and naming but not on semantic fluency or on low-executive demand tasks. Except for semantic fluency, aMCI did not demonstrate an incremental effect on the scores compared to LLD, while AD did, for all the tasks except phonemic fluency.
CONCLUSION
Assessment of semantic memory can be a discriminating clue for the distinction between depression and Alzheimer's disease but some methodological variables are highly influential to the scores, especially education. However, high-executive semantic tasks alone do not allow us to clearly distinguish LLD from AD or aMCI, as both pathologies seem to have a largely dialectical influential relationship, but low-executive semantic tasks appear as more sensible to this pathological distinction.
PubMed: 37563432
DOI: 10.1007/s10433-023-00780-z -
The Journal of Neuroscience : the... Jul 2019Reading involves the rapid extraction of sound and meaning from print through a cooperative division of labor between phonological and lexical-semantic processes....
Reading involves the rapid extraction of sound and meaning from print through a cooperative division of labor between phonological and lexical-semantic processes. Whereas lesion studies of patients with stereotyped acquired reading deficits contributed to the notion of a dissociation between phonological and lexical-semantic reading, the neuroanatomical basis for effects of lexicality (word vs pseudoword), orthographic regularity (regular vs irregular spelling-sound correspondences), and concreteness (concrete vs abstract meaning) on reading is underspecified, particularly outside the context of strong behavioral dissociations. Support vector regression lesion-symptom mapping (LSM) of 73 left hemisphere stroke survivors (male and female human subjects) not preselected for stereotyped dissociations revealed the differential contributions of specific cortical regions to reading pseudowords (ventral precentral gyrus), regular words (planum temporale, supramarginal gyrus, ventral precentral and postcentral gyrus, and insula), and concrete words (pars orbitalis and pars triangularis). Consistent with the primary systems view of reading being parasitic on language-general circuitry, our multivariate LSM analyses revealed that phonological decoding depends on perisylvian areas subserving sound-motor integration and that semantic effects on reading depend on frontal cortex subserving control over concrete semantic representations that aid phonological access from print. As the first study to localize the differential cortical contributions to reading pseudowords, regular words, and concrete words in stroke survivors with variable reading abilities, our results provide important information on the neurobiological basis of reading and highlight the insights attainable through multivariate, process-based approaches to alexia. Whereas fMRI evidence for neuroanatomical dissociations between phonological and lexical-semantic reading is abundant, evidence from modern lesion studies establishing the differential contributions of specific brain regions to specific reading processes is lacking. Our application of multivariate lesion-symptom mapping revealed that effects of lexicality, orthographic regularity, and concreteness on reading differentially depend on areas subserving auditory-motor integration and semantic control. Phonological decoding of print relies on a dorsal perisylvian network supporting auditory and articulatory representations, with unfamiliar words relying especially on articulatory mapping. In tandem with this dorsal decoding system, anterior inferior frontal gyrus may coordinate control over concrete semantic representations that support mapping of print to sound, which is a novel potential mechanism for semantic influences on reading.
Topics: Adult; Brain; Female; Humans; Linguistics; Magnetic Resonance Imaging; Male; Middle Aged; Reading; Semantics; Stroke
PubMed: 31061085
DOI: 10.1523/JNEUROSCI.2707-18.2019 -
Research Square Jul 2023The purpose of this study was to investigate how ataxia affects the task-dependent role of pitch auditory feedback control in speech. In previous research, individuals...
PURPOSE
The purpose of this study was to investigate how ataxia affects the task-dependent role of pitch auditory feedback control in speech. In previous research, individuals with ataxia produced over-corrected, hypermetric compensatory responses to unexpected pitch and formant frequency perturbations in auditory feedback in sustained vowels and single words (Houde et al., 2019; Li et al., 2019; Parrell et al., 2017). In this study, we investigated whether ataxia would also affect the task-dependent role of the auditory feedback control system, measuring whether pitch-shift responses would be mediated by speech task or semantic focus pattern as they are in neurologically healthy speakers.
METHODS
Twenty-two adults with ataxia and 29 age- and sex-matched control participants produced sustained vowels and sentences with and without corrective focus while their auditory feedback was briefly and unexpectedly perturbed in pitch by +/-200 cents. The magnitude and latency of the reflexive pitch-shift responses were measured as a reflection of auditory feedback control.
RESULTS
Individuals with ataxia produced larger reflexive pitch-shift responses in both the sustained-vowel and sentence-production tasks than the control participants. Additionally, a differential response magnitude was observed by task and sentence focus pattern for both groups.
CONCLUSION
These findings demonstrate that even though accuracy of auditory feedback control correction is affected by cerebellar damage, as evidenced by the hypermetric responses, the system still retains efficiency in utilizing the task-dependent role of auditory feedback.
PubMed: 37547022
DOI: 10.21203/rs.3.rs-3186155/v1 -
Journal of Cognitive Neuroscience Aug 2021Prior knowledge, such as schemas or semantic categories, influences our interpretation of stimulus information. For this to transpire, prior knowledge must first be...
Prior knowledge, such as schemas or semantic categories, influences our interpretation of stimulus information. For this to transpire, prior knowledge must first be reinstated and then instantiated by being applied to incoming stimuli. Previous neuropsychological models implicate the ventromedial prefrontal cortex (vmPFC) in mediating these functions for schemas and the anterior/lateral temporal lobes and related structures for categories. vmPFC, however, may also affect processing of semantic category information. Here, the putative differential role of the vmPFC in the reinstatement and instantiation of schemas and semantic categories was examined by probing network-level oscillatory dynamics. Patients with vmPFC damage (n = 11) and healthy controls (n = 13) were instructed to classify words according to a given schema or category, while electroencephalography was recorded. As reinstatement is a preparatory process, we focused on oscillations occurring 500 msec prior to stimulus presentation. As instantiation occurs at stimulus presentation, we focused on oscillations occurring between stimulus presentation and 1000 msec poststimulus. We found that reinstatement was associated with prestimulus, theta and alpha desynchrony between vmPFC and the posterior parietal cortex for schemas, and between lateral temporal lobe and inferotemporal cortex for categories. Damage to the vmPFC influenced both schemas and categories, but patients with damage to the subcallosal vmPFC showed schema-specific deficits. Instantiation showed similar oscillatory patterns in the poststimulus time frame, but in the alpha and beta frequency bands. Taken together, these findings highlight distinct but partially overlapping neural mechanisms implicated in schema- and category-mediated processing.
Topics: Humans; Knowledge; Parietal Lobe; Prefrontal Cortex; Semantics; Temporal Lobe
PubMed: 34375423
DOI: 10.1162/jocn_a_01746 -
Cerebral Cortex (New York, N.Y. : 1991) Aug 2022Neurodegeneration has multiscalar impacts, including behavioral, neuroanatomical, and neurofunctional disruptions. Can disease-differential alterations be captured...
Neurodegeneration has multiscalar impacts, including behavioral, neuroanatomical, and neurofunctional disruptions. Can disease-differential alterations be captured across such dimensions using naturalistic stimuli? To address this question, we assessed comprehension of four naturalistic stories, highlighting action, nonaction, social, and nonsocial events, in Parkinson's disease (PD) and behavioral variant frontotemporal dementia (bvFTD) relative to Alzheimer's disease patients and healthy controls. Text-specific correlates were evaluated via voxel-based morphometry, spatial (fMRI), and temporal (hd-EEG) functional connectivity. PD patients presented action-text deficits related to the volume of action-observation regions, connectivity across motor-related and multimodal-semantic hubs, and frontal hd-EEG hypoconnectivity. BvFTD patients exhibited social-text deficits, associated with atrophy and spatial connectivity patterns along social-network hubs, alongside right frontotemporal hd-EEG hypoconnectivity. Alzheimer's disease patients showed impairments in all stories, widespread atrophy and spatial connectivity patterns, and heightened occipitotemporal hd-EEG connectivity. Our framework revealed disease-specific signatures across behavioral, neuroanatomical, and neurofunctional dimensions, highlighting the sensitivity and specificity of a single naturalistic task. This investigation opens a translational agenda combining ecological approaches and multimodal cognitive neuroscience for the study of neurodegeneration.
Topics: Alzheimer Disease; Atrophy; Biomarkers; Brain; Frontotemporal Dementia; Humans; Magnetic Resonance Imaging; Neurodegenerative Diseases; Neuropsychological Tests
PubMed: 34875690
DOI: 10.1093/cercor/bhab421 -
Cognitive Neuropsychology 2022We assessed effects of semantic interference in people with aphasia (PWA). Two naming tasks (continuous naming and cyclic blocking) were contrasted with tasks which...
We assessed effects of semantic interference in people with aphasia (PWA). Two naming tasks (continuous naming and cyclic blocking) were contrasted with tasks which required suppression of competitors but minimized lexical access (probe task) or required extra-lexical mechanisms of control (Stroop task). In continuous naming, some PWA showed increased interference compared to control participants, with slower RTs and increased omissions. Others showed normal or weaker interference effects in terms of RTs but increased semantic errors. Patterns were consistent only between naming tasks. We explain results by assuming that some PWA are slow at implementing mechanisms of control/selection which weed-out competitors. Others, instead, will have activation difficulties which will induce them to lower the threshold needed for selection. Results highlight how different kinds of brain damage may induce different compensatory strategies and how semantic relatedness may induce both interference and facilitation. Implications for models of lexical selection are discussed.
Topics: Humans; Semantics; Aphasia
PubMed: 36967227
DOI: 10.1080/02643294.2023.2189004 -
Medical Science Educator Feb 2022Lectures remain a common instructional method in medical education. Instructor methods, curricular factors, and technology affect students' use of scheduled live...
BACKGROUND
Lectures remain a common instructional method in medical education. Instructor methods, curricular factors, and technology affect students' use of scheduled live lectures that may impact faculty job satisfaction.
AIM
This study identified instructor methods and curriculum issues that influenced preclinical medical students' use of scheduled lectures as well as faculty perceptions of lectures and students' attendance.
METHODS
First- and second-year osteopathic medical students ( = 304) were invited to complete a voluntary, anonymous semantic differential scale, Likert scale, and dichotomous question survey, rating 22 lecturer methods and 9 curriculum factors that influence use of live lectures. Preclinical faculty ( = 35) were also asked to complete a differential scale survey, rating 17 issues regarding live lectures and student attendance. Student and faculty surveys were analyzed using the appropriate central tendency and variability measures.
RESULTS
Students that completed the survey ( = 144) rated the ability to explain complex concepts in an understandable manner as "Very Important" and wearing professional attire as "Not Important" for attending lectures, respectively. Availability of recorded lectures, time to an upcoming exam, and unscheduled time gaps between lectures were rated as Very Important curricular factors for attending lectures. Faculty completed the survey ( = 21) and agree that lectures should continue as a major mode of instruction, while the majority reported spending over 9 h preparing new lectures.
CONCLUSIONS
Faculty lecture methods and overarching curricular decisions greatly impact students' attendance of live lectures. Regardless, most students and faculty believe that scheduled lectures should continue as an option for students who prefer to attend live lectures.
PubMed: 34877072
DOI: 10.1007/s40670-021-01459-9 -
Frontiers in Artificial Intelligence 2021Though there is a strong consensus that word length and frequency are the most important single-word features determining visual-orthographic access to the mental...
Though there is a strong consensus that word length and frequency are the most important single-word features determining visual-orthographic access to the mental lexicon, there is less agreement as how to best capture syntactic and semantic factors. The traditional approach in cognitive reading research assumes that word predictability from sentence context is best captured by cloze completion probability (CCP) derived from human performance data. We review recent research suggesting that probabilistic language models provide deeper explanations for syntactic and semantic effects than CCP. Then we compare CCP with three probabilistic language models for predicting word viewing times in an English and a German eye tracking sample: (1) Symbolic n-gram models consolidate syntactic and semantic short-range relations by computing the probability of a word to occur, given two preceding words. (2) Topic models rely on subsymbolic representations to capture long-range semantic similarity by word co-occurrence counts in documents. (3) In recurrent neural networks (RNNs), the subsymbolic units are trained to predict the next word, given all preceding words in the sentences. To examine lexical retrieval, these models were used to predict single fixation durations and gaze durations to capture rapidly successful and standard lexical access, and total viewing time to capture late semantic integration. The linear item-level analyses showed greater correlations of all language models with all eye-movement measures than CCP. Then we examined non-linear relations between the different types of predictability and the reading times using generalized additive models. N-gram and RNN probabilities of the present word more consistently predicted reading performance compared with topic models or CCP. For the effects of last-word probability on current-word viewing times, we obtained the best results with n-gram models. Such count-based models seem to best capture short-range access that is still underway when the eyes move on to the subsequent word. The prediction-trained RNN models, in contrast, better predicted early preprocessing of the next word. In sum, our results demonstrate that the different language models account for differential cognitive processes during reading. We discuss these algorithmically concrete blueprints of lexical consolidation as theoretically deep explanations for human reading.
PubMed: 35187472
DOI: 10.3389/frai.2021.730570 -
PloS One 2021Semantic memory representations are overall well-maintained in aging whereas semantic control is thought to be more affected. To explain this phenomenon, this study aims...
Semantic memory representations are overall well-maintained in aging whereas semantic control is thought to be more affected. To explain this phenomenon, this study aims to test the predictions of the Compensation Related Utilization of Neural Circuits Hypothesis (CRUNCH) focusing on task demands in aging as a possible framework. The CRUNCH effect would manifest itself in semantic tasks through a compensatory increase in neural activation in semantic control network regions but only up to a certain threshold of task demands. This study will compare 40 young (20-35 years old) with 40 older participants (60-75 years old) in a triad-based semantic judgment task performed in an fMRI scanner while manipulating levels of task demands (low vs. high) through semantic distance. In line with the CRUNCH predictions, differences in neurofunctional activation and behavioral performance (accuracy and response times) are expected in young vs. old participants in the low- vs. high-demand conditions manifested in semantic control Regions of Interest.
Topics: Adult; Age Factors; Aged; Brain; Brain Mapping; Female; Humans; Magnetic Resonance Imaging; Male; Memory; Memory Disorders; Middle Aged; Psychomotor Performance; Reaction Time; Semantics
PubMed: 34129605
DOI: 10.1371/journal.pone.0249948