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Pesticides are widely-used chemicals commonly applied in agriculture for the protection of crops from pests. Depending on the class of pesticides, the specific substances may have a specific set of adverse effects on humans, especially in cases of acute poisoning. In past years, evidence regarding sequelae of chronic, low-level exposure has been accumulating. Cognitive impairment and dementia heavily affect a person's quality of life and scientific data has been hinting towards an association between them and antecedent chronic pesticide exposure. Here, we reviewed animal and human studies exploring the association between pesticide exposure, cognition and dementia. Additionally, we present potential mechanisms through which pesticides may act neurotoxically and lead to neurodegeneration. Study designs rarely presented homogeneity and the estimation of the exposure to pesticides has been most frequently performed without measuring the synergic effects and the possible interactions between the toxicants within mixtures, and also overlooking low exposures to environmental toxicants. It is possible that a Real-Life Risk Simulation approach would represent a robust alternative for future studies, so that the safe exposure limits and the net risk that pesticides confer to impaired cognitive function can be examined. Previous studies that evaluated the effect of low dose chronic exposure to mixtures of pesticides and other chemicals intending to simulate real life exposure scenarios showed that hormetic neurobehavioral effects can appear after mixture exposure at doses considered safe for individual compounds and these effects can be exacerbated by a coexistence with specific conditions such as vitamin deficiency. However, there is an overall indication, derived from both epidemiologic and laboratory evidence, supporting an association between exposure to neurotoxic pesticides and cognitive dysfunction, dementia and Alzheimer's disease., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Purpose: Relative clauses present a well-known processing asymmetry between object-extracted and subject-extracted dependencies across both typical and atypical populations. The present study aimed at exploring the comprehension of object and subject relative clauses as conceptualized by the Relativized Minimality framework in autistic children and in a group of age- and IQ-matched typically-developing children. The study also explored the way performance in relative clauses would be affected by the children's language and executive function skills. Method: Relative clause comprehension was tested through a sentence-picture matching task and language was tested with a receptive vocabulary task. Executive functions were assessed through backward digit recall and a Flanker test. Results: Object relative clauses were harder to parse for both groups than subject relatives, while number mismatch between the moved object Noun Phrase and the intervening subject Noun Phrase in object relatives boosted both groups' performances. Typically-developing children's performance in object relatives was predicted by both language and executive functions, while autistic children failed to use language and did not systematically draw on their executive functions in object relative clause comprehension. Conclusion: The findings suggest that relative clause processing in autism follows a normal developmental trajectory, and that difficulty with parsing object relative clauses stems from reduced language and executive functions rather than deficits in the children's morphosyntactic skills. [ABSTRACT FROM AUTHOR]

This article is an editorial that discusses the neural mechanisms of language and cognitive performance in individuals with neurodevelopmental disorders, specifically autism. The editorial highlights the challenges that individuals with autism face in language comprehension, auditory processing, expressive language, executive functions, intellectual functioning, and social cognition. The research topic aims to expand the understanding of language and cognitive skills in individuals with autism through various methodological approaches. The article also presents several studies that investigate the relationship between executive functioning and autism symptomatology, cortical auditory processing and verbal communication abilities, embodied language comprehension skills, and language, cognitive, and sensory profiles in individuals with autism and epilepsy. Additionally, the article explores the reading comprehension skills of children with autism and the impact of decoding, fluency, morphological and syntactic, and metalinguistic skills on reading comprehension. The overall findings highlight the neurodevelopmental differences in individuals with autism and emphasize the importance of targeting domain-specific cognitive, sensory, and linguistic disruptions to improve their everyday functioning. [Extracted from the article]

The purpose of the present study was to explore the effects of computer-based multidomain cognitive training program on Greek patients with Mild Cognitive Impairment (MCI). Forty-six patients with MCI were randomly divided into two groups; (a) the training group, which received a computer-based multidomain cognitive training program with the use of the RehaCom software and (b) the control group, which underwent standard-clinical care. The duration of the computer-based training program was 15 weeks, administered twice a week for approximately one hour per session. Analysis of the baseline versus endpoint performance of each group demonstrated that in the control group delayed memory and executive function had deteriorated over the observation period of 15 weeks, while improvement was observed in the training group's performance on delayed memory, word recognition, Boston Naming Test (BNT), Clock Drawing Test (CDT), Semantic Fluency (SF), Trail Making Test-A (TMT-A) and Trail Making Test-B (TMT-B). Comparison between the two groups presented asignificant effect of the intervention for most cognitive domains. These findings are promising for the development of training methods designed to delay cognitive decline in patients with MCI, which is considered to be the prodromal stage of Alzheimer's Disease (AD). [ABSTRACT FROM AUTHOR]

Cognitive impairment is common in multiple sclerosis, but the brain MRI correlates in relapsing remitting multiple sclerosis remain controversial. The current study aimed to investigate whether cognitive decline can be predicted by global and/or regional brain atrophy. Sixty-three patients with relapsing remitting multiple sclerosis (36 men, mean age 39.9 ± 9.4 years old, mean EDSS 1.4 ± 1.2, mean disease duration 4.9 ± 4.3 years) and 46 healthy controls (21 men, mean age 37.5 ± 10.8 years old) were included. Demographic data were obtained, and a longitudinal neuropsychological and global and regional MRI brain volume assessment was performed. The patients performed worse than controls in most neuropsychological tests at baseline. The percentage of patients with clinically meaningful cognitive decline ranged from only 0% to 7.9%. Statistically significant volume reduction was found for all MRI measures except for the left accumbens nucleus. Whole or regional brain atrophy ranged from −0.02% to −0.25%, with subcortical structures showing the largest atrophy rates. A total of 22.2% to 93.7% patients showed atrophy across the brain structures assessed volumetrically. It was regional rather than whole-brain changes that significantly predicted cognitive decline for the patients in the tasks that tested processing speed, visuo-spatial and inhibition skills. The overall data suggest that the progression of cognitive impairment in relapsing remitting multiple sclerosis as captured by conventional neuropsychological testing is the tip of the iceberg of neurodegenerative sequelae in the disease. Also, regional volumetric changes are better than whole-brain atrophy at predicting cognitive dysfunction. [ABSTRACT FROM AUTHOR]

We investigated the on-line processing of unaccusative and unergative sentences in a group of eight Greek-speaking individuals diagnosed with Broca aphasia and a group of language-unimpaired subjects used as the baseline. The processing of unaccusativity refers to the reactivation of the postverbal trace by retrieving the mnemonic representation of the verb's syntactically defined antecedent provided in the early part of the sentence. Our results demonstrate that the Broca group showed selective reactivation of the antecedent for the unaccusatives. We consider several interpretations for our data, including explanations focusing on the transitivization properties of nonactive and active voice-alternating unaccusatives, the costly procedure claimed to underlie the parsing of active nonvoice-alternating unaccusatives, and the animacy of the antecedent modulating the syntactic choices of the patients. [ABSTRACT FROM AUTHOR]