ABSTRACT
OBJECTIVE: To determine how results on the EXAmen Cognitif abrégé en Traumatologie (EXACT), a new test specifically designed to briefly assess global cognitive functioning during the acute phase of traumatic brain injury (TBI), can predict long-term functional outcome compared with length of posttraumatic amnesia (PTA), a well-established predictor. DESIGN: Inception cohort. SETTINGS: Level 1 trauma center. PARTICIPANTS: A total of 90 patients (N=90) hospitalized for a moderate or severe TBI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Performance on the EXACT in the first 3 months after injury and results on the Disability Rating Scale (DRS) at follow-up 1-2 years later. RESULTS: EXACT scores were all correlated with length of PTA and DRS result. Compared with length of PTA, the EXACT added significantly to the regression and improved prediction of functional outcome. More specifically, a total score ≤80 on the EXACT was associated with a higher rate of long-term disability because of more severe TBI consequences. Behavioral regulation and executive functions were the cognitive domains that showed the most impairment, followed by attention and working memory as well as episodic memory. Except for length of PTA and hospital stay, the DRS score was not correlated with other demographic (age, education) or clinical variables (Glasgow Coma Scale and maximum score on the Therapy Intensity Level Scale). CONCLUSIONS: The EXACT can be administered to most patients early in the acute phase of TBI, and results could be used, along with other predictors such as PTA, to estimate their long-term functional sequelae. The EXACT may be a promising brief cognitive instrument for future studies investigating recovery after TBI.
Subject(s)
Brain Injuries, Traumatic , Brain Injuries , Humans , Brain Injuries/psychology , Brain Injuries, Traumatic/psychology , Glasgow Coma Scale , Neuropsychological Tests , Executive Function , Recovery of FunctionABSTRACT
Prospective memory (PM) problems in aging and, to a greater extent, in mild cognitive impairment (MCI), compromise functional independence. This study examined the effectiveness of a cognitive training program based on visual imagery to improve PM among older adults with and without MCI. Participants were older adults, 24 with MCI and 24 cognitively healthy (HOA). Half of them (12 MCI and 12 HOA) were randomly assigned to the PM training program, the other half to the no-training control group. All participants also completed a pre- and post-test evaluation, including neuropsychological tests, questionnaires, and the Ecological Test of Prospective Memory (TEMP). There was no significant effect of the intervention on the TEMP total, event-based or time-based scores for either the MCI or HOA groups. However, the trained MCI group committed fewer false alarms (i.e., more efficient identification of prospective cues) in the event-based condition of the TEMP at post-test. On the other hand, all trained participants performed better than control participants on retrospective memory tests, which suggests that visual imagery-based training is more effective to improve retrospective memory than PM. Possible explanations for these results are explored.
Subject(s)
Cognitive Dysfunction , Memory, Episodic , Aged , Humans , Memory Disorders , Neuropsychological Tests , Retrospective StudiesABSTRACT
Accumulating evidence over the past decade suggests that semantic deficits represent a consistent feature of Mild Cognitive Impairment (MCI). A meta-analysis was performed to examine if semantic deficits are consistently found in patients with MCI. Studies meeting all inclusion criteria were selected for the current meta-analysis. An effect size and a weight were calculated for each study. A random effect model was performed to assess the overall difference in semantic performances between MCI patients and healthy subjects. 22 studies (476 healthy participants, 476 MCI patients, mean Mini Mental Status Examination of the MCI patients: 27.05 ± 0.58) were included in the meta-analysis. Results indicate that MCI patients systematically performed significantly worse than healthy matched controls in terms of overall semantic performance (mean effect size of 1.02; 95% CI [0.80; 1.24]). Semantic deficits are a key feature of MCI. Semantic tests should be incorporated in routine clinical assessments.
Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Memory , Memory Disorders , Neuropsychological Tests , SemanticsABSTRACT
OBJECTIVES: Multiple sclerosis (MS) is a disease of the central nervous system that can interfere with cognitive functions. The purpose of this study is to document the impact of MS, aging and disease duration on cognitive functioning as both life expectancy and incidence of the disease among persons with MS (PwMS) aged 50 years and over (late-onset MS) are increasing in the last two decades. METHODS: Exhaustive neuropsychological evaluation was performed in 84 PwMS (30 young, 30 elderly adult-onset, 25 elderly late-onset) and 50 control participants (25 young, 24 elderly). ANCOVAs and hierarchical linear regressions were used to meet the objectives. RESULTS: Interaction effects were found between age and presence of MS on higher executive function and information processing speed/working memory. After controlling for confounding variables (fatigue, quality of life, depression, MS course, comorbidity), results demonstrated an important role of age on all cognitive functions but only a trend of disease duration on information processing speed/working memory. CONCLUSION: Decline in higher executive functions and information processing speed/working memory in aging is accentuated by the presence of MS, but the impact of age and MS on memory are independent. Age appears to be the variable having the most important role on cognition.
Subject(s)
Aging , Cognition , Multiple Sclerosis , Adult , Aged , Humans , Middle Aged , Multiple Sclerosis/complications , Neuropsychological Tests , Quality of LifeABSTRACT
BACKGROUND: Although cognitive deficits are frequent in multiple sclerosis (MS), screening for them with tools such as the Montreal Cognitive Assessment (MoCA) test is usually not performed unless there is a subjective complaint. The Multiple Sclerosis Neuropsychological Questionnaire (MSNQ) is among the instruments most commonly used to assess self-reported subjective complaints in MS. Nonetheless, it does not always accurately reflect cognitive status; many patients with cognitive deficits thus fail to receive appropriate referral for detailed neuropsychological evaluation. The objective of this study was to examine the validity of the MoCA test to detect the presence of objective cognitive deficits among patients with MS without subjective complaints using the Minimal Assessment of Cognitive Function in MS (MACFIMS) as the gold standard. METHODS: The sample included 98 patients who were recruited from a university hospital MS clinic. The MSNQ was used to select patients without subjective cognitive complaints who also completed the MACFIMS, MoCA test and MSQOL-54. RESULTS: 23.5% of patients without subjective cognitive complaints had evidence of objective cognitive impairment on the MACFIMS (z score < -1.5 on two or more tests). The MoCA had a sensitivity of 87% and a specificity of 68% for detecting objective cognitive impairment in this patient population using a cut-off score of 27. CONCLUSION: A significant proportion of patients without self-reported cognitive impairment do have evidence of cognitive deficits on more exhaustive cognitive assessment. The MoCA is a rapid screening test that could be used to target patients for whom a more detailed neuropsychological assessment would be recommended.
Subject(s)
Cognitive Dysfunction , Multiple Sclerosis , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/etiology , Humans , Mental Status and Dementia Tests , Multiple Sclerosis/complications , Multiple Sclerosis/diagnosis , Neuropsychological Tests , Sensitivity and Specificity , Surveys and QuestionnairesABSTRACT
A new Q555X mutation on the SYN1 gene was recently found in several members of a family segregating dyslexia, epilepsy, and autism spectrum disorder. To describe the effects of this mutation on cortical gray matter microstructure, we performed a surface-based group study using novel diffusion and quantitative multiparametric imaging on 13 SYN1Q555X mutation carriers and 13 age- and sex-matched controls. Specifically, diffusion kurtosis imaging (DKI) and neurite orientation and dispersion and density imaging (NODDI) were used to analyze multi-shell diffusion data and obtain parametric maps sensitive to tissue structure, while quantitative metrics sensitive to tissue composition (T1, T2* and relative proton density [PD]) were obtained from a multi-echo variable flip angle FLASH acquisition. Results showed significant microstructural alterations in several regions usually involved in oral and written language as well as dyslexia. The most significant changes in these regions were lowered mean diffusivity and increased fractional anisotropy. This study is, to our knowledge, the first to successfully use diffusion imaging and multiparametric mapping to detect cortical anomalies in a group of subjects with a well-defined genotype linked to language impairments, epilepsy and autism spectrum disorder (ASD).
Subject(s)
Brain/diagnostic imaging , Cell Cycle Proteins/genetics , Gray Matter/diagnostic imaging , Mutation , Adolescent , Adult , Aged , Family , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Multimodal Imaging , Pedigree , Synapsins , Young AdultABSTRACT
OBJECTIVES: Although multiple sclerosis (MS) has long been considered to primarily affect white matter, it is now recognized that cognitive deficits in MS are also related to neocortical, thalamic and hippocampal damage. However, the association between damage to these structures and memory deficits in MS is unclear. This study examines whether MS patients with cognitive impairment have a reduction of hippocampal and/or thalamic volumes compared to cognitively intact patients, and whether these volume reductions correlate with various aspects of memory function. METHODOLOGY: Volumetric MRI measures of thalamus and hippocampus of forty-one patients with MS were performed. The patients were divided in two groups depending on the presence or absence of cognitive impairment, based on their neuropsychological tests scores. RESULTS: Right hippocampal volume was found to be associated with learning, and the left thalamic volume was found to predict performance in verbal memory. Cognitively impaired patients had a tendency to have a reduced left thalamic volume compared to cognitively intact patients. CONCLUSIONS: This study does not support a direct relationship between hippocampal atrophy and verbal memory. These results add to the growing evidence of the involvement of thalamus in cognitive impairment in MS and its association with verbal memory deficits.
Subject(s)
Hippocampus/pathology , Memory Disorders/pathology , Memory/physiology , Multiple Sclerosis/pathology , Thalamus/pathology , Adult , Atrophy/diagnostic imaging , Atrophy/pathology , Atrophy/psychology , Female , Hippocampus/diagnostic imaging , Humans , Magnetic Resonance Imaging/methods , Male , Memory Disorders/diagnostic imaging , Memory Disorders/psychology , Middle Aged , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/psychology , Neuropsychological Tests , Organ Size/physiology , Thalamus/diagnostic imagingABSTRACT
Clinical symptoms observed in Alzheimer's disease (AD) patients may reflect variations within specific large-scale brain networks, modeling AD as a disconnection syndrome. The present magnetic resonance imaging study aims to compare the organization of gray matter structural covariance networks between 109 cognitively unimpaired controls (CTRL) and 109 AD patients positive to beta-amyloid at the early stages of the disease, using voxel-based morphometry. The default-mode network (DMN; medial temporal lobe subsystem) was less extended in AD patients in comparison with CTRL, with a significant decrease in the structural association between the entorhinal cortex and the medial prefrontal and the dorsolateral prefrontal cortices. The DMN (midline core subsystem) was also less extended in AD patients. Trends toward increased structural association were observed in the salience and executive control networks. The observed changes suggest that early disruptions in structural association between heteromodal association cortices and the entorhinal cortex could contribute to an isolation of the hippocampal formation, potentially giving rise to the clinical hallmark of AD, progressive memory impairment. It also provides critical support to the hypothesis that the reduced connectivity within the DMN in early AD is accompanied by an enhancement of connectivity in the salience and executive control networks.
Subject(s)
Alzheimer Disease/diagnostic imaging , Brain/diagnostic imaging , Gray Matter/diagnostic imaging , Adult , Aged , Aged, 80 and over , Alzheimer Disease/cerebrospinal fluid , Amyloid beta-Peptides/cerebrospinal fluid , Biomarkers/cerebrospinal fluid , Female , Humans , Magnetic Resonance Imaging , Male , Mental Status Schedule , Middle Aged , Neural Pathways/diagnostic imaging , Peptide Fragments/cerebrospinal fluidABSTRACT
OBJECTIVE: Prospective memory (PM) is a cognitive function defined as the ability to perform an intention at an appropriate moment in the future. In the aging population, PM is essential for maintaining independent daily living. Introduced as a simple and quick way to assess PM in clinical settings, the envelope task has to date received very limited empirical and practical interest. METHODS: The present study investigated the task's clinical utility in detecting PM impairment in a sample composed of 49 healthy older adults (OA), 41 patients with Alzheimer's disease, and 64 individuals with amnestic and nonamnestic mild cognitive impairment (MCI) of heterogeneous etiology: 17 of idiopathic nature, 20 presenting an idiopathic rapid-eye movement sleep behaviour disorder, and 27 patients diagnosed with idiopathic Parkinson's disease. RESULTS: The envelope task was highly sensitive and specific in discriminating Alzheimer's disease patients from OA. Although it was specific in distinguishing MCI individuals from OA, its sensitivity was modest, especially in patients presenting a nonamnestic MCI subtype. CONCLUSIONS: Given its high specificity and simple low-cost administration procedure, the envelope task is a promising instrument for clinicians who seek to rapidly assess PM impairment in their daily practice.
Subject(s)
Alzheimer Disease/diagnosis , Cognitive Dysfunction/diagnosis , Dementia/diagnosis , Executive Function/physiology , Memory, Episodic , Neuropsychological Tests , Aged , Aged, 80 and over , Female , Humans , Male , Mental Status Schedule , Middle Aged , Parkinson Disease/diagnosis , REM Sleep Behavior Disorder/diagnosis , ROC CurveABSTRACT
OBJECTIVE: Prospective memory (PM), the ability to remember to do something at the appropriate time in the future, is crucial in everyday life. One way to improve PM performance is to increase the salience of a cue announcing that it is time to act. Multiple sclerosis (MS) patients often report PM failures and there is growing evidence of PM deficits among this population. However, such deficits are poorly characterized and their relation to cognitive status remains unclear. To better understand PM deficits in MS patients, this study investigated the impact of cue salience on PM, and its relation to retrospective memory (RM) and executive deficits. METHODS: Thirty-nine (39) MS patients were compared to 18 healthy controls on a PM task modulating cue salience during an ongoing general knowledge test. RESULTS: MS patients performed worse than controls on the PM task, regardless of cue salience. MS patients' executive functions contributed significantly to the variance in PM performance, whereas age, education and RM did not. Interestingly, low- and high-executive patients' performance differed when the cue was not salient, but not when it was, suggesting that low-executive MS patients benefited more from cue salience. CONCLUSIONS: These findings add to the growing evidence of PM deficits in MS and highlight the contribution of executive functions to certain aspects of PM. In low-executive MS patients, high cue salience improves PM performance by reducing the detection threshold and need for environmental monitoring.
Subject(s)
Cognitive Dysfunction/physiopathology , Cues , Executive Function/physiology , Memory Disorders/physiopathology , Memory, Episodic , Multiple Sclerosis/physiopathology , Adult , Cognitive Dysfunction/etiology , Female , Humans , Male , Memory Disorders/etiology , Middle Aged , Multiple Sclerosis/complicationsABSTRACT
OBJECTIVE: We recently reported a Q555X mutation of synapsin 1 (SYN1) on chromosome Xp11-q21 in a family segregating partial epilepsy and autistic spectrum disorder. Herein, we provide a detailed description of the epileptic syndrome in the original family. METHODS: A total of 34 members from a large French-Canadian family were evaluated. Family members with seizures or epilepsy underwent (when possible) clinical, neuropsychological, electrophysiologic, and neuroimaging assessments. RESULTS: Epilepsy was diagnosed in 10 family members (4 deceased, 6 living). In addition to occasional spontaneous complex partial seizures, seven family members clearly had reflex seizures triggered by bathing or showering. Hippocampal atrophy was found in two of five epileptic family members family members who underwent magnetic resonance (MR) imaging. Video-electroencephalography (EEG) recordings of three triggered seizures in two affected members showed rhythmic theta activity over temporal head regions. Ictal single-photon emission computed tomography (SPECT) showed temporoinsular perfusion changes. Detailed neuropsychological assessments revealed that SYN1 Q555X male mutation carriers showed specific language impairment and mild autistic spectrum disorder. Female carriers also exhibited reading impairments and febrile seizures but no chronic epilepsy. SIGNIFICANCE: Available evidence suggests that impaired SYN1 function is associated with hyperexcitability of the temporoinsular network and disturbance of high mental functions such as language and social interaction. The presence of reflex bathing seizures, a most peculiar clinical feature, could be helpful in identifying other patients with this syndrome.
Subject(s)
Baths/adverse effects , Epilepsies, Partial/genetics , Genetic Diseases, X-Linked/genetics , Reflex/genetics , Seizures/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Epilepsies, Partial/diagnosis , Female , Genetic Diseases, X-Linked/diagnosis , Humans , Male , Middle Aged , Pedigree , Quebec , Seizures/diagnosis , SyndromeABSTRACT
We aimed to characterize difficulties in famous face naming in three poststroke aphasic patients with a lesion limited to the left mid-posterior temporal language regions, sparing the anterior temporal lobe. The patients did not present semantic deficits specific to known people. Nonetheless, they showed difficulties naming famous buildings in addition to famous faces, but they were comparable to healthy controls in generating proper names. Our results support the critical role of the mid-posterior temporal language regions in the lexical retrieval of proper names, namely from pictorial stimuli, in absence of semantic impairments.
Subject(s)
Anomia/pathology , Aphasia/pathology , Mental Recall/physiology , Stroke/complications , Temporal Lobe/pathology , Aged , Anomia/complications , Aphasia/complications , Famous Persons , Female , Humans , Male , Middle Aged , Names , SemanticsABSTRACT
The advantage of selective amygdalohippocampectomy (SAH) over anterior temporal lobectomy (ATL) for the treatment of temporal lobe epilepsy (TLE) remains controversial. Because ATL is more extensive and involves the lateral and medial parts of the temporal lobe, it may be predicted that its impact on memory is more important than SAH, which involves resection of medial temporal structures only. However, several studies do not support this assumption. Possible explanations include task-specific factors such as the extent of semantic and syntactic information to be memorized and failure to control for main confounders. We compared preoperative vs. postoperative memory performance in 13 patients with SAH with 26 patients who underwent ATL matched on side of surgery, IQ, age at seizure onset, and age at surgery. Memory function was assessed using the Logical Memory subtest from the Wechsler Memory Scales - 3rd edition (LM-WMS), the Rey Auditory Verbal Learning Test (RAVLT), the Digit Span subtest from the Wechsler Adult Intelligence Scale, and the Rey-Osterrieth Complex Figure Test. Repeated measures analyses of variance revealed opposite effects of SAH and ATL on the two verbal learning memory tests. On the immediate recall trial of the LM-WMS, performance deteriorated after ATL in comparison with that after SAH. By contrast, on the delayed recognition trial of the RAVLT, performance deteriorated after SAH compared with that after ATL. However, additional analyses revealed that the latter finding was only observed when surgery was conducted in the right hemisphere. No interaction effects were found on other memory outcomes. The results are congruent with the view that tasks involving rich semantic content and syntactical structure are more sensitive to the effects of lateral temporal cortex resection as compared with mesiotemporal resection. The findings highlight the importance of task selection in the assessment of memory in patients undergoing TLE surgery.
Subject(s)
Amygdala/surgery , Anterior Temporal Lobectomy , Drug Resistant Epilepsy/psychology , Drug Resistant Epilepsy/surgery , Hippocampus/surgery , Memory , Neurosurgical Procedures/methods , Psychomotor Performance , Adolescent , Adult , Age of Onset , Child , Female , Functional Laterality/physiology , Humans , Intelligence Tests , Male , Postoperative Complications/psychology , Seizures/surgery , Treatment Outcome , Verbal Learning , Wechsler Scales , Young AdultABSTRACT
Resection of the insular cortex is becoming more frequent as it is increasingly recognized that a nonnegligible proportion of surgical candidates with drug-resistant epilepsy have an epileptogenic zone that involves the insula. In the last decades, however, the insula has been proposed to be involved in several neuropsychological functions, and there is a lack of documentation on whether partial or complete insulectomy results in permanent cognitive impairments in this clinical population. In this study, we conducted standard preoperative and postoperative neuropsychological assessments in 18 patients undergoing epilepsy surgery that included the removal of the insula in the right (n=13) or the left (n=5) hemisphere. Postoperative testing was conducted at least five months after surgery. Cognitive impairments were common and heterogeneous prior to surgery, with language and verbal memory impairments being especially frequent among patients in whom epileptic seizures originated from the left hemisphere. After surgery, declines and improvements occurred on a variety of outcomes, although new deficits were relatively infrequent among patients who had obtained normal performance at baseline. Statistical comparisons between preoperative and postoperative assessments revealed significant deterioration of only one outcome - the color naming condition of the Stroop test - which relies on oro-motor speed and lexical access. These findings suggest that partial or complete resection of the insular cortex in patients with drug-refractory epilepsy can be conducted without major permanent neuropsychological impairments in a vast majority of patients. However, small decrements in specific cognitive functions can be expected, which should also be taken into account when considering the surgical option in this clinical population.
Subject(s)
Cerebral Cortex/surgery , Epilepsy/psychology , Epilepsy/surgery , Neuropsychological Tests , Neurosurgical Procedures/adverse effects , Adult , Cognition Disorders/etiology , Cognition Disorders/psychology , Drug Resistance , Female , Functional Laterality , Humans , Language Disorders/etiology , Language Disorders/psychology , Male , Memory Disorders/etiology , Memory Disorders/psychology , Middle Aged , Postoperative Complications/epidemiology , Postoperative Complications/psychology , Psychomotor Performance , Speech Disorders/etiology , Speech Disorders/psychology , Stroop Test , Treatment Outcome , Young AdultABSTRACT
Semantic deficits in Alzheimer's disease (AD) are often more severe for items that are characterized by a unique semantic and lexical association, such as famous people. Whether these deficits are due to the degradation of semantic information or a deficit in the ability to intentionally access semantic knowledge remains controversial. To assess the integrity of the semantic system without explicitly accessing it, a priming paradigm was used. Semantic and repetition priming effects in individuals with AD (n = 7) and age-matched controls (n = 13) were measured in a familiarity judgment task using visually-presented names of famous people. A defective priming effect in AD subjects was observed in the semantic priming but not in the repetition priming condition. Therefore, the semantic impairments observed in AD may indicate a degraded representation of the semantic information concerning famous people.
Subject(s)
Alzheimer Disease/psychology , Repetition Priming , Semantics , Aged , Aged, 80 and over , Famous Persons , Female , Humans , MaleABSTRACT
OBJECTIVE: To accurately assess prospective memory (PM) functioning in patients who sustained a traumatic brain injury (TBI), it is important to use both subjective (questionnaires) and objective (tests) measures. However, which factors have the most significant effect on each PM measure remains unknown. This observational study aims to verify whether TBI severity or psychological status has the most influence on patients' objective and subjective PM measures. METHOD: Fifteen healthy control (HC) participants (n = 15), 19 patients with a mild TBI (n = 19) and 30 patients with a moderate-to-severe TBI (n = 30) were recruited during the post-acute phase. For almost every participant, a relative was also recruited (n = 62). The Test écologique de mémoire prospective (TEMP), an objective computerized PM measure consisting of naturalistic stimuli, was administered to all participants along with anxiety (BAI) and depression inventories (BDI). Participants and their relatives also completed a questionnaire, the comprehensive assessment of PM (CAPM), a subjective PM measure assessing everyday failures. RESULTS: Results on the objective PM measure were predicted by TBI severity, while psychological symptoms (BAI and BDI) predicted scores on the subjective PM measure. In addition, relatives in the moderate-to-severe TBI group reported more PM failures on the subjective measure and their perception was significantly correlated with results on the objective PM measure, which was not the case for the other two groups of relatives. CONCLUSIONS: Objective PM measures are related to TBI severity and appear more robust against the influence of psychological factors than subjective PM measures.
ABSTRACT
OBJECTIVE: To determine whether the increased vulnerability to semantic interference previously observed in amnestic mild cognitive impairment (aMCI) is specifically associated with semantic material or if it also affects other types of material, suggesting generalized executive and inhibitory impairment. METHOD: Seventy-two participants divided into two groups (33 aMCI, 39 normal control [NC]) matched for age and education were included. They completed a comprehensive neuropsychological examination, the French version of the Loewenstein Acevedo Scale for Semantic Interference and Learning (LASSI-L; semantic interference test), and a homologous experimental phonological test, the phonological interference and learning test. Independent sample t tests, mixed analysis of variance (ANOVA), and analysis of covariance (ANCOVA) on memory and interference scores were conducted to compare memory and interference in both conditions for both groups. RESULTS: For memory scores, results revealed significant main effects of group (NC > aMCI) and condition (semantic > phonological) and significant interactions (poorer performance in the semantic condition for aMCI). aMCI committed more phonological false recognition errors, were disproportionately more vulnerable to retroactive semantic interference, and showed a higher percentage of intrusion errors associated with proactive semantic interference than NC. CONCLUSIONS: To our knowledge, this is the first study to compare vulnerability to interference in aMCI and normal aging with two similarly designed semantic and phonological word list learning tasks. Taken together, our results suggest that aMCI present with broad difficulties in source memory and inhibition, but that impaired deep semantic processing results in additional semantic intrusion errors during proactive interference and impacts their ability to show good recall after an interference list (greater semantic retroactive interference). Results are discussed according to the level-of-processing and activation/monitoring theories. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
Subject(s)
Aging , Amnesia , Cognitive Dysfunction , Semantics , Humans , Cognitive Dysfunction/physiopathology , Male , Female , Aged , Amnesia/physiopathology , Amnesia/complications , Aging/physiology , Neuropsychological Tests , Middle Aged , Aged, 80 and over , PhoneticsABSTRACT
The insula is often considered the fifth lobe of the brain and is increasingly recognized as one of the most connected regions in the brain, with widespread connections to cortical and subcortical structures. As a follow-up to our previous tractography work, we investigated the resting-state functional connectivity (rsFC) profiles of insular subregions and assessed their concordance with structural connectivity. We used the CONN toolbox to analyze the rsFC of the same 19 insular regions of interest (ROIs) we used in our prior tractography work and regrouped them into six subregions based on their connectivity pattern similarity. Our analysis of 50 healthy participants confirms the known broad connectivity of the insula and shows novel and specific whole-brain and intra-connectivity patterns of insular subregions. By examining such subregions, our findings provide a more detailed pattern of connectivity than prior studies that may prove useful for comparison between patients.
ABSTRACT
OBJECTIVE: Mild cognitive impairment (MCI) is a risk factor for developing Alzheimer's disease (AD), and about half of older people with MCI will progress to AD within the next 5 years. The aim of the present study was to compare the semantic performance of MCI progressors (MCI-p) and nonprogressors (MCI-np). The hypothesis was that MCI-p would present with poorer semantic performance relative to MCI-np at baseline, indicating that semantic deficits may increase the risk of future decline toward AD. METHOD: Fifty-six MCI participants (aged 65-89) from the Consortium for Early Identification of Alzheimer's Disease-Quebec study were analyzed, with 18 progressing and 38 remaining stable over 2 years. Analysis of covariance assessed their initial semantic and nonsemantic cognitive performance, and mixed analyses of variance gauged longitudinal patterns of cognitive decline at the 2-year follow-up. RESULTS: In the semantic domain, MCI-p performed significantly worse than MCI-np at baseline on two semantic tests (category fluency and object decision). In other cognitive domains, MCI-p performed worse than MCI-np on a test of executive functions (cognitive flexibility) but showed similar performance on a test of episodic memory. There were no significant differences between groups in the rates of progression on semantic tests over the 2-year period, but a steeper decline was observed in MCI-p at follow-up on tests of global cognition, episodic memory, and processing speed. CONCLUSION: This suggest that MCI patients who present with semantic memory impairment in addition to episodic memory impairment are at greater risk of future progression to AD. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
Subject(s)
Cognitive Dysfunction , Disease Progression , Neuropsychological Tests , Semantics , Humans , Cognitive Dysfunction/physiopathology , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/psychology , Male , Female , Aged , Aged, 80 and over , Executive Function/physiology , Memory, Episodic , Longitudinal Studies , Alzheimer Disease/psychology , Alzheimer Disease/complications , Alzheimer Disease/physiopathologyABSTRACT
OBJECTIVE: Prospective memory (PM) is the ability to remember to produce an action at a specific moment in the future signaled by the occurrence of a specific event (event-based [EB] condition), a time or a time interval (time-based [TB] condition). Detection of the appropriate moment corresponds to the prospective component, while production of the appropriate action corresponds to the retrospective component. Although PM difficulties have been reported in healthy aging and in association with multiple sclerosis (MS), PM has not been examined in older persons with MS (PwMS). The main objective of this study was to investigate whether the decline in PM performance with advancing age is influenced by the presence of MS. This study also aimed to clarify the type of PM impairment (prospective vs. retrospective component in TB and EB conditions) in MS as a function of age. METHOD: A total of 80 participants were recruited and separated into four groups: older PwMS (n = 20), younger PwMS (n = 20), older controls (n = 20), and younger controls (n = 20). PM and its components were measured using the Test Ecologique de Mémoire Prospective (TEMP), an experimental ecological tool using naturalistic stimuli developed by our laboratory that has been validated in previous studies. RESULTS: On the TEMP total score, a two-way analysis of covariance showed a main effect of age, a main effect of the presence of MS, as well as a significant Age × Disease interaction. Direct comparison between EB and TB conditions revealed that for the prospective component, only older PwMS had more difficulty in the TB than in the EB condition, whereas the retrospective component score was significantly lower in the TB than in the EB condition in all groups except in younger controls. CONCLUSIONS: The TEMP revealed a marked impairment in PM in older PwMS compared to older controls and young PwMS. This impairment was particularly evident on the prospective component in the TB condition. Retrospective difficulties noted in the TB condition in all, but younger controls reflect the arbitrary nature of the cue-action link that is particularly sensitive to episodic memory difficulties often observed in aging and MS. (PsycInfo Database Record (c) 2024 APA, all rights reserved).