Bioaccumulation of arsenic and selenium in bycatch fishes Diapterus peruvianus, Pseudupeneus grandisquamis, and Trachinotus kennedyi from shrimp trawling in the continental shelf of Guerrero, México.

With the aim of determining arsenic (As) and selenium (Se) concentrations in bycatch fishes from SW Mexico and comparing elemental concentrations with limits for human consumption set in the national and international legislation, three fish species (Diapterus peruvianus, Pseudupeneus grandisquamis, and Trachinotus kennedyi) were collected from Guerrero state during trawling operations. Additionally, As and Se levels in muscle tissue were compared with similar species from diverse areas. The order of As and Se concentrations was T. kennedyi>P. grandisquamis>D. peruvianus. In Mexico, there is no regulation of As and Se levels in fish. In comparison to the legal limit (0.1 µg g(-1) wet weight) set by legislation in Venezuela, As levels in the edible portion of T. kennedyi (0.632 µg g(-1) wet weight), P. grandisquamis (0.166 µg g(-1) wet weight), and D. peruvianus (0.157 µg g(-1) wet weight) were above this limit. In the case of Se, average concentrations in T. kennedyi (0.323 µg g(-1) wet weight) were above the maximum permissible limit (0.30 µg g(-1) wet weight) set in the Chilean legislation. Se concentrations in Carangoides bajad from Saudi Arabia were comparable to values in T. kennedyi (this study). In relation to As, concentrations varied in magnitude orders; the highest As concentration (range 10.35 to 23.71 µg g(-1) wet weight) corresponded to Mullus barbatus from the Iberian Mediterranean.

Subjective memory complaints in the elderly: Prevalence and influence of temporal orientation, depression and quality of life in a population-based study in the city of Madrid.

OBJECTIVES: It is still a matter of debate whether variables such as education, sex, age, personality and others underlie subjective memory complaints (SMC). Our objectives are to study: the prevalence of memory complaints in the city of Madrid, the distribution of complaints in the population according to socio-demographic variables and the related variables like cognitive performance, quality of life, perceived health status and functional ability. To our knowledge, this is the first study about the prevalence of SMC in Spain. METHODS: We adopted a transversal descriptive epidemiological study. The survey sample size is 1637 persons above 64 years. SMC were obtained through questions regarding memory complaints. RESULTS: 524 (32.4%) subjects reported SMC. The prevalence of SMC depends on age, education, sex, mood and cognitive performance. SMC rises from 24% in the 65-69 age groups to 57% in the 90 and above group. The percentage of subjects with SMC was 52.8% among persons diagnosed with depression or anxiety, and 28.7% among subjects without. Performance on cognitive tests such as orientation showed that subjects without orientation failures (81%) have a 22.2% SMC frequency and subjects who fail all the orientation items (4%) have a 93% frequency. A logistic regression analysis showed that those variables indicating a better prediction of group membership (SMC vs. controls) were orientation in time, quality of life and depression-anxiety. CONCLUSION: Complaints reflect various processes and are the result of various elements; however, our study highlights the importance of factors such as cognitive performance, depression-anxiety and quality of life.

Effects of Untreated Drinking Water at Three Indigenous Yaqui Towns in Mexico: Insights from a Murine Model.

BACKGROUND: Reports in a northwestern Mexico state linked arsenic (As) in drinking water to DNA damage in people from indigenous communities. However, this correlation remains under discussion due to unknown variables related to nutrition, customs, and the potential presence of other metal(oid)s. METHODS: To determine this association, we sampled water from three Yaqui towns (Cócorit, Vícam, and Pótam), and analyzed the metals by ICP-OES. We exposed four separate groups, with five male CD-1 mice each, to provide further insight into the potential effects of untreated drinking water. RESULTS: The maximum concentrations of each metal(oid) in µg·L-1 were Sr(819) > Zn(135) > As(75) > Ba(57) > Mo(56) > Cu(17) > Al(14) > Mn(12) > Se(19). Histological studies revealed brain cells with angulation, satellitosis, and reactive gliosis with significant statistical correlation with Mn and As. Furthermore, the liver cells presented hepatocellular degeneration. Despite the early response, there is no occurrence of both statistical and significative changes in hematological parameters. CONCLUSIONS: The obtained results provide experimental insights to understand the potential effects of untreated water with low As and Mn contents in murine models. This fact is noteworthy because of the development of histological changes on both the brain and liver at subchronic exposure.

Metal bioaccessibility, particle size distribution and polydispersity of playground dust in synthetic lysosomal fluids.

Inhalation of playground dust-derived fine particles in schoolyards poses a risk from exposure to metal(oids) and minerals. In this work, we obtained the total concentration and bioaccessibility of metal(oids) with Gamble Solution (GS) and Artificial Lysosomal Fluid (ALF) synthetic solutions, simulating the extracellular neutral pH environment of the lung and the intracellular conditions of the macrophage, respectively. Scanning Electron Microscope (SEM), and Dynamic Light Scattering analysis (DLS) techniques were used to characterize particles with a size smaller than 2.5 µm, which can be assimilated by macrophages in the deep part of the lung. Arsenic (As), lead (Pb), copper (Cu), manganese (Mn), zinc (Zn), and iron (Fe) showed concentrations of 39.9, 147.9, 286, 1369, 2313, 112,457 mg·kg-1, respectively. The results indicated that all studied elements were enriched when compared to (i) local geochemical background and (ii) findings reported in other cities around the world. Bioaccessibility of metal(oids) in GS was low-moderate for most studied elements. However, in ALF assays, bioaccessibility was high among the samples: for lead (Pb = 34-100%), arsenic (As = 14.7-100%), copper (Cu = 17.9-100%), and zinc (Zn = 35-52%) possibly related to hydrophobic minerals in dust. SEM and DLS image analysis showed that playground dust particles smaller than 2.5 µm are dominant, particularly particles with a size range of 500-600 nm. The polydispersity detected in these particle sizes showed that most of them might be crystalline compounds (elongated shapes) forming agglomerates instead of combustion particles (spheres). Moreover, the circularity detected varies from 0.57 to 0.79 (low roundness), which corroborates this finding. The presence of agglomerates of ultrafine/nanoparticles containing highly bioaccessible metals in playground sites may have severe implications in children's health. Therefore, further studies are required to characterize the size distribution, structure, shape and composition of such minerals which are essential factors related to the toxicology of inhaled dust particles.

How cognitive reserve influences older adults' cognitive state, executive functions and language comprehension: A structural equation model.

Cognitive reserve has been defined as the individuals' ability to tolerate age-related and neurodegenerative changes in the brain without developing clinical symptoms or signs of disease. Formal education, occupational attainment, and knowledge of other languages have been assessed as the most relevant factors determining cognitive reserve. The main objective of this study was to develop a structural equation model that reflects the direct influence of cognitive reserve on old adults' general cognitive status and executive functioning, and indirectly on sentence comprehension performance through executive functions mediation. One hundred and fifty eight Spanish-speaking older adults, cognitively intact, were assessed to obtain cognitive reserve data, general cognitive status, executive functioning (inhibitory control, working memory and cognitive flexibility), and sentence comprehension measures. High indicators of adjustment of the proposed model were obtained. The most related factors to cognitive reserve were education and occupational attainment. As we hypothesize, cognitive reserve had a higher direct significant relation to cognitive status and, in a lesser extent, to executive functioning. Participants' general cognitive status and executive function were high and directly related. Furthermore, cognitive reserve has an indirect positive relation to sentence comprehension via executive functions' mediation.

The role of soil mineralogy on oral bioaccessibility of lead: Implications for land use and risk assessment.

Understanding the oral bioaccessibility of lead (Pb) present in soils in urbanized areas is important for the human exposure risk assessment. In particular, the role of the soil-mineralogy in the oral bioaccessibility has not been extensively studied. To investigate bioaccessibility, five types of periurban soils were collected, samples were spiked with the same amount of lead-chromates from traffic paint, and subjected to the in vitro Physiological Based Extraction Test (PBET). Ten samples of urban topsoils were collected at elementary schools playgrounds, Pb-bioaccessibility was measured, and a prediction equation for bioaccessibility was constructed. Mineralogy, and metal content were identified with a combination of X-ray powder diffraction, scanning electron microscopy, and portable X-ray fluorescence techniques. Traffic paint sample is made of 15% quartz (SiO2), 13% crocoite (PbCrO4), 55% calcite (CaCO3), and 17% kaolinite (Al2Si2O5(OH)4) and it contains high metal content (Pb, Cr, Zn, and Ca). Studied soils are characterized by variable amounts of acid-neutralizing minerals (carbonates) and low metal content. Spiked soils contained almost equal concentration of Pb, Cr, and Zn, because the contribution of these metals is from the added paint. However, obtained Pb-bioaccessibility at gastric and intestinal conditions are variable (40 to 51% gastric, 24 to 70.5% intestinal). Carbonate content shows significant correlation (p < 0.05) with Cr, Ca, calcite, crocoite, and Pb-bioaccessible at gastric conditions. Correlation of Pb-bioaccessible at intestinal conditions is significant (p < 0.05) with kaolinite. Variability of Pb-bioaccesibility in urban environments is commonly associated to differences in Pb-sources, however, our results show that the bioaccessibility of the same pollutant behaves different for each soil type. This suggests that soil mineralogy may play a role in Pb-releasing at gastrointestinal conditions. Soil information about mineralogical characteristics from this study may help to reduce exposure to lead from urban sources if data are incorporated into urban planning.

Factors Explaining Language Performance After Training in Elders With and Without Subjective Cognitive Decline.

The present study explores if cognitive reserve, executive functions, and working memory capacity are predictive of performance in the language domain (specifically in sentence comprehension and naming) after a cognitive training intervention. Sixty-six Spanish older adults voluntarily participated in the study, classified either as older adults with subjective cognitive decline according to Jessen et al.'s (2014) criteria (n = 35; 70.94 ± 4.16 years old) or cognitively intact (n = 31; 71.34 ± 4.96 years old). Written sentence comprehension and visual confrontation naming were assessed both immediately after recruitment (at the baseline), and then 6 months later, once each participant had completed his/her cognitive training (a well-known program in Spain, called UMAM; English translation: Madrid City Council Memory Unit Program). Cognitive reserve, executive functions (cognitive flexibility and controlled interference efficiency), and working memory capacity were measured for all participants at the baseline. Results pointed out that the subjective cognitive decline group presented greater benefits in the language domain than cognitively intact participants. We also observed that lower executive functioning and working memory capacity at the baseline predicted larger benefits in language performance after training, but only in the group of cognitively intact older adults. However, selected predictors hardly explained subjective cognitive decline participants' results in language performance after training.

Efficacy of Cognitive Training in Older Adults with and without Subjective Cognitive Decline Is Associated with Inhibition Efficiency and Working Memory Span, Not with Cognitive Reserve.

The present study explores the role of cognitive reserve, executive functions, and working memory (WM) span, as factors that might explain training outcomes in cognitive status. Eighty-one older adults voluntarily participated in the study, classified either as older adults with subjective cognitive decline or cognitively intact. Each participant underwent a neuropsychological assessment that was conducted both at baseline (entailing cognitive reserve, executive functions, WM span and depressive symptomatology measures, as well as the Mini-Mental State Exam regarding initial cognitive status), and then 6 months later, once each participant had completed the training program (Mini-Mental State Exam at the endpoint). With respect to cognitive status the training program was most beneficial for subjective cognitive decline participants with low efficiency in inhibition at baseline (explaining a 33% of Mini-Mental State Exam total variance), whereas for cognitively intact participants training gains were observed for those who presented lower WM span.

Functional Connectivity Disruption in Subjective Cognitive Decline and Mild Cognitive Impairment: A Common Pattern of Alterations.

Functional connectivity (FC) alterations represent a key feature in Alzheimer's Disease (AD) and provide a useful tool to characterize and predict the course of the disease. Those alterations have been also described in Mild Cognitive Impairment (MCI), a prodromal stage of AD. There is a growing interest in detecting AD pathology in the brain in the very early stages of the disorder. Subjective Cognitive Decline (SCD) could represent a preclinical asymptomatic stage of AD but very little is known about this population. In the present work we assessed whether FC disruptions are already present in this stage, and if they share any spatial distribution properties with MCI alterations (a condition known to be highly related to AD). To this end, we measured electromagnetic spontaneous activity with MEG in 39 healthy control elders, 41 elders with SCD and 51 MCI patients. The results showed FC alterations in both SCD and MCI compared to the healthy control group. Interestingly, both groups exhibited a very similar spatial pattern of altered links: a hyper-synchronized anterior network and a posterior network characterized by a decrease in FC. This decrease was more pronounced in the MCI group. These results highlight that elders with SCD present FC alterations. More importantly, those disruptions affected AD typically related areas and showed great overlap with the alterations exhibited by MCI patients. These results support the consideration of SCD as a preclinical stage of AD and may indicate that FC alterations appear very early in the course of the disease.

APOE ε4 Modulation of Training Outcomes in Several Cognitive Domains in a Sample of Cognitively Intact Older Adults.

BACKGROUND: Most research points to the ɛ4 allele of the apolipoprotein E (APOE) gene as the most recognizable genetic risk factor associated with Alzheimer's disease pathogenesis. It has been also suggested that the APOEɛ4 allele has a negative influence on cognitive functioning, which begins long before cognitive impairment becomes manifest. However, still, little is known about the APOEɛ4 interaction with cognitive intervention programs. OBJECTIVE: The main goal of this study was to explore whether there was a differential APOE genotype modulation effect after cognitive training in different domains, such as language comprehension, executive functions, and memory. Contrary to other studies, hippocampal volume was controlled for. METHODS: Fifty older adults (65+ years; 30 women and 20 men) participated in a multi-domain cognitive training that involved 30 sessions taking place over 12 weeks. Half of the participants were APOEɛ4 carriers. The control group was matched in age, gender, normalized hippocampal volume, cognitive reserve, Mini-Mental State Examination score, and Geriatric Depression Scale-Short Version. RESULTS: The study revealed that there were consistent treatment benefits in complex sentence comprehension (noncanonical sentences and sentences with two propositions), a domain that was not directly trained, but only in the A POEɛ4 noncarrier group. CONCLUSION: Genetic profile modulates training outcomes in sentence comprehension.

Association of perceived health and depression with older adults' subjective memory complaints: contrasting a specific questionnaire with general complaints questions.

The objectives of this paper were to evaluate the association of subjective memory complaints (SMC) with perceived state of health, mood and episodic memory (associative and everyday memory). We studied these areas using two different complaint assessment methods (three general questions and a validated scale). The study included 269 older adults (aged 65-87) with age-related memory changes, but without cognitive impairment. They were evaluated with Mini-cognitive Exam, Rivermead Behavioural Memory Test (a test of everyday memory), Paired Associates Learning Test, Memory Failures of Everyday Questionnaire, three memory complaints questions, Nottingham Health Profile and Geriatric Depression Scale. The results indicated that memory for everyday performance, mood and perceived health were independent predictors of SMC, with mood and perceived health being stronger predictors than actual memory performance. Age was not associated with subjective memory and, with regard to level of education, only the illiterate level was associated with SMC. A specific questionnaire on subjective memory was found to be preferable to an aggregate of complaints questions on self-reported memory; only health profile was found to predict the outcomes on memory complaints questions. Our conclusion is that a group of underlying factors other than everyday memory were playing a role in SMC; these SMC of subjects with age-related memory changes were mainly associated with subjective evaluations of their health.

Synchronization during an internally directed cognitive state in healthy aging and mild cognitive impairment: a MEG study.

Mild cognitive impairment (MCI) is a stage between healthy aging and dementia. It is known that in this condition the connectivity patterns are altered in the resting state and during cognitive tasks, where an extra effort seems to be necessary to overcome cognitive decline. We aimed to determine the functional connectivity pattern required to deal with an internally directed cognitive state (IDICS) in healthy aging and MCI. This task differs from the most commonly employed ones in neurophysiology, since inhibition from external stimuli is needed, allowing the study of this control mechanism. To this end, magnetoencephalographic (MEG) signals were acquired from 32 healthy individuals and 38 MCI patients, both in resting state and while performing a subtraction task of two levels of difficulty. Functional connectivity was assessed with phase locking value (PLV) in five frequency bands. Compared to controls, MCIs showed higher PLV values in delta, theta, and gamma bands and an opposite pattern in alpha, beta, and gamma bands in resting state. These changes were associated with poorer neuropsychological performance. During the task, this group exhibited a hypersynchronization in delta, theta, beta, and gamma bands, which was also related to a lower cognitive performance, suggesting an abnormal functioning in this group. Contrary to controls, MCIs presented a lack of synchronization in the alpha band which may denote an inhibition deficit. Additionally, the magnitude of connectivity changes rose with the task difficulty in controls but not in MCIs, in line with the compensation-related utilization of neural circuits hypothesis (CRUNCH) model.

[Relationship between memory complaints and memory performance, mood and sociodemographic variables in young adults]. / Relacion de las quejas de memoria con el rendimiento de memoria, el estado de animo y variables sociodemograficas en adultos jovenes.

INTRODUCTION: Neurological consultations due to memory complaints have increased in recent years in both older and younger people. Few investigations have studied the variables related to memory complaints in young adults. AIM: To analyze, in a sample of young adults, the relationship between memory complaints and objective memory performance, depressive and anxiety symptoms, age, sex and level of studies. SUBJECTS AND METHODS: The study included 582 healthy workers, without cognitive impairment, aged 22-64 years. ASSESSMENT: Word List and Family Scenes of Wechsler Memory Scale-III, Memory Failures of Everyday Questionnaire (MFE) and Goldberg Anxiety and Depression Scale. RESULTS: We did not find any significant association between subjective assessment of memory and objective performance, both immediate and delayed in verbal and visual memory. Depression and anxiety had the highest correlation with MFE. The significant variables in the multiple regression analysis were: depression, with the largest effect size, age, college studies and sex. CONCLUSION: In young adults, those which had a greater perception of daily forgetfulness were not those with lesser memory performance. The most important variables involved in memory complaints were depression and anxiety. Younger people, people with college education and men reported less memory complaints.

TITLE: Relacion de las quejas de memoria con el rendimiento de memoria, el estado de animo y variables sociodemograficas en adultos jovenes.Introduccion. Las consultas en neurologia por quejas de memoria se han incrementado en los ultimos años, tanto en mayores como en jovenes. Se han realizado pocos estudios sobre las variables que influyen en las quejas en adultos jovenes. Objetivo. Analizar en esta poblacion la relacion de las quejas con el rendimiento objetivo de memoria, con la depresion y la ansiedad, con la edad, el sexo y el nivel de estudios. Sujetos y metodos. Muestra de 582 individuos trabajadores sin deterioro cognitivo y edad de 22-64 años. Los materiales utilizados fueron listas de palabras y escenas de familia de la escala de memoria de Wechsler, tercera edicion, cuestionario de fallos de memoria de la vida diaria (MFE), y escala de depresion y ansiedad de Goldberg. Resultados. No se encontro asociacion estadisticamente significativa entre la valoracion subjetiva de la memoria y el rendimiento objetivo inmediato o demorado, ni en la memoria visual ni en la verbal. La depresion y la ansiedad fueron las variables con mayor correlacion con la puntuacion global del MFE. En el analisis de regresion, las variables significativas fueron: la depresion, con el mayor tamaño de efecto, la edad, los estudios universitarios y el sexo. Conclusion. Las personas jovenes que manifestaron mas olvidos cotidianos no presentaron un rendimiento menor en las pruebas objetivas de memoria. Las variables mas importantes que intervinieron en las quejas fueron la depresion y la ansiedad. Las personas mas jovenes, las que tenian estudios universitarios y los varones manifestaron menos quejas de memoria.

Memory complaints in the elderly: quality of life and daily living activities. A population based study.

OBJECTIVES: We investigate whether Subjective Memory Complaints (SMC) are associated with specific aspects of quality of life and activities of daily living. METHODS: Cross-sectional descriptive epidemiological study (random sample of the non-institutionalized census population): 1637 subjects over 64 years. SMC were obtained through questions regarding memory complaints. Coop/Wonca questionnaire, Katz Index and Lawton Scale were also administrated. RESULTS: A significant association between SMC with global quality of life and every dimension of quality of life is found (p<0.05). There is also a significant association with every item of Lawton Scale (p<0.001) and Katz Index (p<0.01). Variables associated with SMC identified by logistic regression are: difficulties in using telephone, in taking medication, in social activities and a low self perceived health. DISCUSSION: Subjects with memory complaints are a heterogeneous group. Quality of life and activities of daily living are both associated with SMC.

Early dysfunction of functional connectivity in healthy elderly with subjective memory complaints.

It is still an open question whether subjective memory complaints (SMC) can actually be considered to be clinically relevant predictors for the development of an objective memory impairment and even dementia. There is growing evidence that suggests that SMC are associated with an increased risk of dementia and with the presence of biological correlates of early Alzheimer's disease. In this paper, in order to shed some light on this issue, we try to discern whether subjects with SMC showed a different profile of functional connectivity compared with subjects with mild cognitive impairment (MCI) and healthy elderly subjects. In the present study, we compare the degree of synchronization of brain signals recorded with magnetoencephalography between three groups of subjects (56 in total): 19 with MCI, 12 with SMC and 25 healthy controls during a memory task. Synchronization likelihood, an index based on the theory of nonlinear dynamical systems, was used to measure functional connectivity. Briefly, results show that subjects with SMC have a very similar pattern of connectivity to control group, but on average, they present a lower synchronization value. These results could indicate that SMC are representing an initial stage with a hypo-synchronization (in comparison with the control group) where the brain system is still not compensating for the failing memory networks, but behaving as controls when compared with the MCI subjects.

Increased biomagnetic activity in healthy elderly with subjective memory complaints.

OBJECTIVE: Subjective memory complaints (SMCs) are frequently reported by elderly people with or without objective cognitive impairment (OMI) as assessed by neuropsychological tests. We investigate whether SMCs are associated with altered brain biomagnetic patterns even in the absence of OMI. METHODS: We report spatio-temporal patterns of brain magnetic activity recorded with magnetoencephalography during a memory task in 51 elderly participants divided into the following groups: patients with mild cognitive impairment (MCI) with SMC and OMI, individuals with SMC but not OMI, and healthy controls without neither SMC nor OMI. Exclusion criteria for all three groups included a diagnosis of depression or any other psychiatric condition. RESULTS: No statistically significant differences were found between MCI patients and participants with SMC. However, the SMC showed higher activation, between 200 and 900 ms after stimulus onset, than the control group in posterior ventral regions and in the dorsal pathway. MCI patients showed higher activation than the control group in the posterior part of the ventral pathway. CONCLUSIONS: These findings suggest that similar physiological mechanisms may underlie SMC and MCI, which could be two stages in a cognitive continuum. SIGNIFICANCE: MEG provide different neurophysiological profiles between SMC and control subjects.

Is there a Grammatical Comprehension Deficit in Multidomain Mild Cognitive Impairment? / ¿Hay un déficit de comprensión gramatical en el Deterioro Cognitivo Leve multidominio?

Multidomain mild Cognitive Impairment (mMCI) patients have similar difficulties than those observed in the initial stages of Alzheimer disease. Many studies have explored language abilities in MCI, but few have focused in grammatical comprehension. This study explores the differences between mMCI patients and controls using a complete neuropsychological battery, it tries to find out if vocabulary and grammatical comprehension in both groups are predicted by naming and verbal fluency, and seeks the best subset of sentence structures to classify the subjects. There were significative differences between groups in verbs and in grammatical comprehension. Linear regression revealed that verb and sentence comprehension are independent of naming and verbal fluency performance in mMCI patients. In the control group verb comprehension is predicted by intrusions in verbal fluency, and the comprehension of sentences containing two propositions seems to be related to control processes and recognition errors. Two sentence structures, that do not fit to syntactic canonical order in Spanish, are especially useful for subjects' classification. mMCI patients have a specific deficit affecting grammatical comprehension that doesn't seem to depend on their low performance at lexical-semantic level. In healthy elders, verb and grammatical comprehension are related to control processes.

Pacientes con Deterioro Cognitivo Leve Multidominio (DCLm) tienen dificultades similares a las observadas en las etapas iniciales de la enfermedad de Alzheimer. Algunos estudios han explorado las habilidades lingüísticas en pacientes con DCLm, pero pocos se han centrado en la comprensión gramatical. Este estudio explora las diferencias entre pacientes con DCLm y controles. Utilizando una batería neuropsicológica completa, tratamos de determinar si la denominación y la fluidez verbal predicen los resultados en vocabulario y comprensión gramatical en ambos grupos, y buscamos el mejor subconjunto de estructuras oracionales para clasificar a los sujetos. Se encontraron diferencias significativas entre los grupos en la comprensión de verbos y de oraciones. La regresión lineal reveló que la comprensión de verbos y de oraciones son independientes del rendimiento en denominación y en fluidez verbal en pacientes con DCLm. En el grupo control, la comprensión de verbos fue pronosticada por el número de intrusiones en la tarea de fluidez verbal, mientras que la comprensión de oraciones con dos proposiciones parece estar relacionada con procesos de control y errores de reconocimiento. Dos tipos de oraciones no ajustadas al orden sintáctico canónico del español resultaron especialmente útiles para la clasificación de los sujetos. Los pacientes con DCLm presentan un déficit específico que afecta la comprensión gramatical que no parece depender de su bajo rendimiento en el nivel léxico-semántico. En los ancianos sanos, tanto la comprensión de verbos como la de oraciones se relacionan con los procesos de control.