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Temporal lobe epilepsy (TLE) is the most common form of focal epilepsy and is associated with a variety of structural and psychological alterations. Recently, there has been renewed interest in using brain tissue resected during epilepsy surgery, in particular 'non-epileptic' brain samples with normal histology that can be found alongside epileptic tissue in the same epileptic patients - with the aim being to study the normal human brain organization using a variety of methods. An important limitation is that different medical characteristics of the patients may modify the brain tissue. Thus, to better determine how 'normal' the resected tissue is, it is fundamental to know certain clinical, anatomical and psychological characteristics of the patients. Unfortunately, this information is frequently not fully available for the patient from which the resected tissue has been obtained - or is not fully appreciated by the neuroscientists analyzing the brain samples, who are not necessarily experts in epilepsy. In order to present the full picture of TLE in a way that would be accessible to multiple communities (e.g., basic researchers in neuroscience, neurologists, neurosurgeons and psychologists), we have reviewed 34 TLE patients, who were selected due to the availability of detailed clinical, anatomical, and psychological information for each of the patients. Our aim was to convey the full complexity of the disorder, its putative anatomical substrates, and the wide range of individual variability, with a view toward: (1) emphasizing the importance of considering critical patient information when using brain samples for basic research and (2) gaining a better understanding of normal and abnormal brain functioning. In agreement with a large number of previous reports, this study (1) reinforces the notion of substantial individual variability among epileptic patients, and (2) highlights the common but overlooked psychopathological alterations that occur even in patients who become seizure-free after surgery. The first point is based on pre- and post-surgical comparisons of patients with hippocampal sclerosis and patients with normal-looking hippocampus in neuropsychological evaluations. The second emerges from our extensive battery of personality and projective tests, in a two-way comparison of these two types of patients with regard to pre- and post-surgical performance.

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 test the hypothesis that there is increased low-frequency activity located predominantly in the frontal lobe in patients with major depressive disorder using magnetoencephalography.We carried out an unmatched or separate sampling case-control study of 31 medication-free patients who met the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV), criteria for major depressive disorder and were outpatients of the Hospital Central de la Defensa, Madrid, and 22 healthy control subjects with no history of mental illness. A logistic regression analysis was employed to examine the predictive value of magnetoencephalography dipole density scores in the diagnosis of depression. We attempted to locate generators of focal magnetic slow waves by employing a single moving dipole model and by calculating dipole densities in prefrontal, frontal, parietal, temporal and occipital areas. The study lasted from February 2001 to January 2003.Only 2 dipole density scores, right occipital delta and left temporal delta, were significantly related to depression. According to the comparison of univariate and multivariate models and odds ratios, the right occipital delta dipole density is the factor with the greatest predictive power for depression, and the only one to show a significant correlation with severity of depression.We did not find any frontal lobe functional alteration. Our study provides, to the best of our knowledge, the first evidence of abnormal focal magnetic low-frequency activity in the occipital lobe of untreated patients with depression. Increased occipital lobe delta dipole density seems to be a reliable risk factor for depression, which correlates with disease severity according to the Hamilton Rating Scale for Depression.

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.