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Our incomplete understanding of the link between Alzheimer's Disease pathology and symptomatology is a crucial obstacle for therapeutic success. Recently, translational studies have begun to connect the dots between protein alterations and deposition, brain network dysfunction and cognitive deficits. Disturbance of neuronal activity, and in particular an imbalance in underlying excitation/inhibition (E/I), appears early in AD, and can be regarded as forming a central link between structural brain pathology and cognitive dysfunction. While there are emerging (non-)pharmacological options to influence this imbalance, the complexity of human brain dynamics has hindered identification of an optimal approach. We suggest that focusing on the integration of neurophysiological aspects of AD at the micro-, meso- and macroscale, with the support of computational network modeling, can unite fundamental and clinical knowledge, provide a general framework, and suggest rational therapeutic targets. M.A.B. is supported by the UK Dementia Research Institute which receives its funding from DRI Ltd, funded by the Medical Research Council, Alzheimer’s Society and Alzheimer Research UK (UKDRI1010). M.A.B. is also funded by a UK RI Future Leaders Fellowship (MR/S017003/1) and a grant from the right Focus Foundation (A2019112S). F.M is supported by the Spanish Minister of Science (RTI2018-098762-B-C31), University of Texas Houston Research Staff grant, NIH− HCP (Connectomics of Aging Brain and Dementia). J.dF was supported by Centro de Investigacion ´ en Red sobre Enfermedades Neurodegenerativas (CIBERNED, CB06/05/0066, Spain); theSpanish “Ministerio de Ciencia e Innovacion´ ”(grant PGC2018-094307-B-I00 and the Cajal Blue Brain Project [the Spanish partner of the Blue Brain Project initiative from EPFL, Switzerland]).

Determinar si la realización de una tarea de reconocimiento con interferencia activa, producía cambios en los patrones de activación cerebral con respecto a la presentación de otra con interferencia pasiva. Población y metodología: en veinte ancianos sanos se midió con magnetoencefalografía. Se realizó a cada uno de ellos la escala de Memoria de Wechsler-III (WMS-III), la escala de Inteligencia de Wechsler, el Boston Naming Test, el test de fluidez verbal, el test de clasificación de tarjetas de Wisconsin, el trail Making Test y el test de colores y palabras (STROOP). Los registros se llevaron a cabo mediante un magnetoencefalógrafo de 148 canales capaz de medir la actividad magnética generada en toda la convexidad craneal. Resultados: encontramos una mayor activación en la condición de interferencia activa en las regiones mediales temporales, corteza visual, y región ventral anterior durante los primeros 400 milisegundos en el hemisferio izquierdo y únicamente en el derecho para la corteza visual, mientras que en la condición de interferencia pasiva, se obtuvo una mayor activación en la región ventral anterior durante los 700-800 milisegundos en el hemisferio izquierdo. Conclusión: la presentación de estos dos tipos de interferencia, activa y pasiva, modula los patrones de activación fronto-temporales en el envejecimiento normal, To determine whether performing a recognition task under interference conditions produces changes in brain activity pattern compared with the activity seen under conditions of passive interference. Population and methods: Twenty healthy elderly subjects were subjected to magnetoencephalography. In each patient we applied the Wechsler Memory Scale-III (WMS-III), the Wechsler Intelligence Scale, the Boston Naming Test, the verbal fluency test, the Wisconsin card classification test, the Trail Making Test and the colors and words test (STROOP). The recordings were made using a 148-channel magnetoencephalograph capable of measuring the magnetic activity generated within the entire cranial convexity. Results: Greater activation was recorded under active interference conditions in the medial temporal regions, visual cortex and anterior ventral area in the first 400 ms in the left hemisphere and only in the right hemisphere for the visual cortex, while under passive interference conditions, increased activation was obtained in the anterior ventral region during the 700-800 ms in the left hemisphere. Conclusion: The presentation of both types of interference, active and passive, modulates the fronto-temporal activation patterns in normal aging

To localize the cortical regions for language in patients who are to have brain surgery.We made a SPECT (Single Photon Emission using Computerized Tomography) study of cerebral perfusion in 14 patients with drug-resistant temporal epilepsy who were candidates for brain surgery. The patients were selected consecutively from those attending for surgical assessment. We selected the patients in whom two 99mTc-HMPAO studies could be done in the same week: one without sensory stimulation and one whilst listening and repeating a series of ordinary words in fairly frequent use. The two studies were assessed qualitatively (on a 16 colour image scale, with a background subtraction of 20% and standardized to the point of maximum uptake). Changes were considered to be significant when a greater intensity of two colours was localized and semiquantitative (with regular areas of interest, of 4 x 4 pixels, placed on the region in which the qualitative change was observed and referenced to cerebellar activity).We found increased perfusion in the temporo-parietal regions in 11 of the 14 patients. In most (9/14 cases) this was bilateral and in two cases on the left only. We observed a certain predominant pattern: a bilateral increase in temporal perfusion, involving the more anterior regions of the left hemisphere and also the middle and posterior regions of the right hemisphere. The maximum percentage increase in perfusion on semiquantitative assessment was 12%.Although the changes seen may correspond to activation in the cortical regions related to different cerebral functions, we consider that with the SPECT technique one may detect changes in perfusion of the regions of the brain which are involved in language processing.

Neuropsychology is a discipline included in the neurosciences which, over the past twenty years, has shown its value in the assessment and rehabilitation of cognitive functions in different disorders. In particular, in epilepsy it has permitted the description of the different factors which affect cognitive deterioration; permitted the establishment of profiles of cognitive deterioration and also the evaluation of the adverse effects of some anti-epileptic drugs on cognition.In this paper we confirm the value of neuropsychology in an Epilepsy Unit and describe different procedures for evaluation, as well as the cognitive consequences of the surgery of epilepsy.

To carry out a critical evaluation of the international literature on the neuropsychology of epilepsy. The variables which lead to cognitive deterioration in epilepsy and the effect on cognition of different treatments available (pharmacological and surgical).We evaluate the influence of different neurological variables on the higher functions (aetiology, age of onset, type of crises, duration of illness, frequency and anti-epileptic drugs). We also describe the cognitive functions most affected in epilepsy (memory, attention, executive function, language). Studies of the surgery of epilepsy show that this may lead to both beneficial and undesirable effects on cognition.The variables which in general most affect higher functions are the duration of the illness and the frequency and types of crises. The commonest neuropsychological effects are those of memory deficit. These studies show that neuropsychological studies should be done from the time of onset of the disorder. Finally, from the surgical point of view, young patients with considerable crisis reduction or free of crises, with moderate preoperative deterioration of memory have the greatest possibility of post-operative improvement in cognition. Older persons with intact cognitive function and major surgical resection have more possibilities of post-surgical deterioration.

A magnetoencefalografia é uma técnica de neuroimagem funcional que permite descrever os padrões espacio-temporais da actividade cerebral relacionada com diferentes processos cognitivos básicos [...]. Submitted by Ana Santos (anas@uportu.pt) on 2016-10-28T10:39:37Z No. of bitstreams: 1 Sara.Fernandes_Sinapse_Vol8_N2_Nov08.pdf: 250321 bytes, checksum: ca5ebcf16e1e0157baa25153a2b9d49f (MD5) Made available in DSpace on 2016-10-28T10:39:38Z (GMT). No. of bitstreams: 1 Sara.Fernandes_Sinapse_Vol8_N2_Nov08.pdf: 250321 bytes, checksum: ca5ebcf16e1e0157baa25153a2b9d49f (MD5) Previous issue date: 2008