SchizophreniaLempel-Ziv complexity Magnetoencephalography Neurodevelopmental Neurodegenerative• Schizophrenic patients show higher complexity values as compared to controls.• Schizophrenic patients showed a tendency to reduced complexity values as a function of age while controls showed the opposite tendency.• The tendency observed in schizophrenic patients parallels the tendency observed in Alzheimer disease patients. ABSTRACTObjective: The neurodevelopmental-neurodegenerative debate is a basic issue in the field of the neuropathological basis of schizophrenia (SCH). Neurophysiological techniques have been scarcely involved in such debate, but nonlinear analysis methods may contribute to it. Methods: Fifteen patients (age range 23-42 years) matching DSM IV-TR criteria for SCH, and 15 sex-and age-matched control subjects (age range 23-42 years) underwent a resting-state magnetoencephalographic evaluation and Lempel-Ziv complexity (LZC) scores were calculated. Results: Regression analyses indicated that LZC values were strongly dependent on age. Complexity scores increased as a function of age in controls, while SCH patients exhibited a progressive reduction of LZC values. A logistic model including LZC scores, age and the interaction of both variables allowed the classification of patients and controls with high sensitivity and specificity. Conclusions: Results demonstrated that SCH patients failed to follow the "normal" process of complexity increase as a function of age. In addition, SCH patients exhibited a significant reduction of complexity scores as a function of age, thus paralleling the pattern observed in neurodegenerative diseases. Significance: Our results support the notion of a progressive defect in SCH, which does not contradict the existence of a basic neurodevelopmental alteration.

Nonlinear analyses have shown that Alzheimer disease (AD) patients' brain activity is characterized by a reduced complexity and connectivity. The aim of this study is to define complexity patterns of mild cognitive impairment (MCI) patients. Whole-head magnetoencephalography recordings were obtained from 18 diagnosed AD patients, 18 MCI patients, and 18 healthy controls during resting conditions. Lempel-Ziv complexity (LZC) values were calculated. MCI patients exhibited intermediary LZC scores between AD patients and controls. A combination of age and posterior LZC scores allowed ADs-MCIs discrimination with 94.4% sensitivity and specificity, whereas no LZC score allowed MCIs---controls discrimination. AD patients and controls showed a parallel tendency to diminished LZC scores as a function of age, but MCI patients did not exhibit such "normal" tendency. Accordingly, anterior LZC scores allowed MCIs-controls discrimination for subjects below 75 years. MCIs exhibited a qualitatively distinct relationship between aging and complexity reduction, with scores higher than controls in older individuals. This fact might be considered a new example of compensatory mechanism in MCI before fully established dementia.

Over three months of intensive training with a tactile stimulation device, 18 blind and 10 blindfolded seeing subjects improved in their ability to identify geometric figures by touch. Seven blind subjects spontaneously reported ‘visual qualia’, the subjective sensation of seeing flashes of light congruent with tactile stimuli. In the latter subjects tactile stimulation evoked activation of occipital cortex on electroencephalography (EEG). None of the blind subjects who failed to experience visual qualia, despite identical tactile stimulation training, showed EEG recruitment of occipital cortex. None of the blindfolded seeing humans reported visual-like sensations during tactile stimulation. These findings support the notion that the conscious experience of seeing is linked to the activation of occipital brain regions in people with blindness. Moreover, the findings indicate that provision of visual information can be achieved through non-visual sensory modalities which may help to minimize the disability of blind individuals, affording them some degree of object recognition and navigation aid.

New diagnostic criteria for Alzheimer's disease (AD) stress the role of in vivo biomarkers. Neurophysiological markers are usually not considered as such criteria, although theoretical and practical reasons would justify them. In order to assess the value of neurophysiology as an AD biomarker, whole-head magnetoencephalographic (MEG) resting state recordings were obtained from 35 AD patients, 23 mild cognitive impairment (MCI) patients, and 24 healthy controls. The AD group was further split into two groups differing in severity according to the GDS/FAST criteria. A Minimum Norm Estimation procedure was utilized to estimate the cortical origin of slow brain oscillatory activity in the delta band (2-4 Hz). Eight regions of interest (ROIs) discriminated between AD patients and controls. Delta current density (DCD) in all ROIs showed a significant negative correlation with cognitive status (p < 0.001). DCD values in posterior parietal, occipital, prerolandic, and precuneus cortices distinguished reliably between MCI patients, AD patients with different severity scores, and controls. Importantly, an increase of DCD in right parietal cortex and precuneus indexed the transition from MCI to mild dementia and from mild to more severe dementia. MEG delta mapping might be a serious candidate for a "neural degeneration" marker of AD reflecting dysfunctional synaptic transmission. More importantly, the localization of DCD values is in line with functional imaging markers of AD. However, MEG delta mapping is a totally non-invasive technique that directly measures neural activity. We propose that individuals with enhanced DCD in posterior parietal and precuneus cortices are at risk of progression to full dementia.

Recent proposals of diagnostic criteria within the healthy aging-Alzheimer's disease (AD) continuum stressed the role of biomarker information. More importantly, such information might be critical to predict those mild cognitive impairment (MCI) patients at a higher risk of conversion to AD. Usually, follow-up studies utilize a reduced number of potential markers although the conversion phenomenon may be deemed as multifactorial in essence. In addition, not only biological but also cognitive markers may play an important role. Considering this background, we investigated the role of cognitive reserve, cognitive performance in neuropsychological testing, hippocampal volumes, APOE genotype, and magnetoencephalography power sources to predict the conversion to AD in a sample of 33 MCI patients. MCIs were followed up during a 2-year period and divided into two subgroups according to their outcome: The "stable" MCI group (sMCI, 21 subjects) and the "progressive" MCI group (pMCI, 12 subjects). Baseline multifactorial information was submitted to a hierarchical logistic regression analysis to build a predictive model of conversion to AD. Results indicated that the combination of left hippocampal volume, occipital cortex theta power, and clock drawing copy subtest scores predicted conversion to AD with a 100% of sensitivity and 94.7% of specificity. According to these results it might be suggested that anatomical, cognitive, and neurophysiological markers may be considered as "first order" predictors of progression to AD, while APOE or cognitive reserve proxies might play a more secondary role.

Lung IRI caused dysregulation miRNA. The administration of lidocaine reduced significantly miRNAs alterations.

Background: Subjects with mild cognitive impairment (MCI) are at a higher risk of experiencing Alzheimer disease (AD). Magnetoencephalographic temporoparietal dipole densities of low-frequency activity are good predictors of individuals' cognitive status, and might be a useful tool to investigate the conversion from MCI to AD. Objective: To investigate the role of low-frequency dipole densities as predictors of the risk of developing AD. Design: Whole-head magnetoencephalographic recordings were obtained from 19 probable AD patients, 17 MCI patients, and 17 healthy control subjects. The generators of focal magnetic slow waves were located using a single moving dipole model. Results: Left parietal ␦ dipole density permitted a reliable classification of AD and MCI patients. The MCI patients were divided into 2 groups based on the median left parietal ␦ dipole density, and were followed up for 2 years. The estimated relative risk of conversion to AD was increased by 350% in those MCI patients with high left parietal ␦ dipole density scores. Conclusions: Results confirmed the important role of parietal ␦ dipole density in the evaluation of AD and MCI. A magnetoencephalographic-based assessment of AD and MCI patients might be considered a useful clinical test in the near future.

Purpose of the study: Everyday memory of older persons does not improve with intensive memory training programs. This study proposes a change in these programs based on a time-extended and massive intervention format.Design and Methods: The sample of 1007 healthy older persons (mean age 71.85; SD = 5.12) was randomized into 2 groups. The experimental group followed an extended 6 years of training (192 sessions over 192 weeks) whereas the control group received an intensive training (3 sessions per week for a total of 32 sessions in 11 weeks). The program included cognitive and emotional content whose effects were assessed with the Rivermead Behavioral Memory Test (RBMT) and with the Mini-Mental State Examination (MMSE). Both groups were evaluated initially, after 32 sessions, and again after 6 years.Results: The relative improvements measured with Blom’s derivative showed that everyday memory and mental status of the experimental group were significantly better both in the short (Δ% 8.31 in RBMT and Δ% 1.51 in MMSE) and in the long term (Δ% 12.54 in RBMT and Δ% 2.56 in MMSE). For everyday memory and mental level, the overall gain estimate representing the mean difference in pre-post change between time-extended and intensive groups was 0.27 (95% CI: 0.13–0.40) and 0.54 (95% CI: 0.40–0.67), respectively. Time-extended programs have significantly improved everyday memory in contrast with the usual intensive programs whose effects decay with time. There are also significant increases in mental level scores while daily life functionality is preserved in all subjects who completed the training.Implications: These results suggest that it is possible to preserve everyday memory in the long term with continuous training and practice. Massive and time-extended formats may contribute in the future to a paradigm shift in memory programs for healthy older people.